plan: web previews for channels (#7022)

* plan: web previews for channels

* types for recipient side to support channel web previews and domain names

* fix

* migrations

* update schema and api types

* update schema

* rename migrations

* core: check member role

---------

Co-authored-by: Evgeny @ SimpleX Chat <259188159+evgeny-simplex@users.noreply.github.com>

apps/ios/SimpleXChat/ChatTypes.swift

@@ -2531,10 +2531,22 @@ public enum GroupType: Codable, Hashable {
     }
 }
 
+public struct PublicGroupAccess: Codable, Hashable {
+    public var groupWebPage: String?
+    public var groupDomain: String?
+    public var domainWebPage: Bool = false
+    public var allowEmbedding: Bool = false
+}
+
+public struct RelayCapabilities: Codable, Hashable {
+    public var baseWebUrl: String?
+}
+
 public struct PublicGroupProfile: Codable, Hashable {
     public var groupType: GroupType
     public var groupLink: String
     public var publicGroupId: String
+    public var publicGroupAccess: PublicGroupAccess?
 }
 
 public struct GroupProfile: Codable, NamedChat, Hashable {
@@ -2703,6 +2715,7 @@ public struct GroupRelay: Identifiable, Decodable, Equatable, Hashable {
     public var userChatRelay: UserChatRelay
     public var relayStatus: RelayStatus
     public var relayLink: String?
+    public var relayCap: RelayCapabilities
     public var id: Int64 { groupRelayId }
 }
 

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/model/ChatModel.kt

@@ -2209,11 +2209,25 @@ object GroupTypeSerializer : KSerializer<GroupType> {
   }
 }
 
+@Serializable
+data class PublicGroupAccess(
+  val groupWebPage: String? = null,
+  val groupDomain: String? = null,
+  val domainWebPage: Boolean = false,
+  val allowEmbedding: Boolean = false
+)
+
+@Serializable
+data class RelayCapabilities(
+  val baseWebUrl: String? = null
+)
+
 @Serializable
 data class PublicGroupProfile(
   val groupType: GroupType,
   val groupLink: String,
-  val publicGroupId: String
+  val publicGroupId: String,
+  val publicGroupAccess: PublicGroupAccess? = null
 )
 
 @Serializable
@@ -2337,7 +2351,8 @@ data class GroupRelay(
   val groupMemberId: Long,
   val userChatRelay: UserChatRelay,
   val relayStatus: RelayStatus,
-  val relayLink: String? = null
+  val relayLink: String? = null,
+  val relayCap: RelayCapabilities
 ) {
   val id: Long get() = groupRelayId
 }

bots/api/TYPES.md

@@ -146,6 +146,7 @@ This file is generated automatically.
 - [Profile](#profile)
 - [ProxyClientError](#proxyclienterror)
 - [ProxyError](#proxyerror)
+- [PublicGroupAccess](#publicgroupaccess)
 - [PublicGroupData](#publicgroupdata)
 - [PublicGroupProfile](#publicgroupprofile)
 - [RCErrorType](#rcerrortype)
@@ -157,6 +158,7 @@ This file is generated automatically.
 - [RcvFileTransfer](#rcvfiletransfer)
 - [RcvGroupEvent](#rcvgroupevent)
 - [RcvMsgError](#rcvmsgerror)
+- [RelayCapabilities](#relaycapabilities)
 - [RelayProfile](#relayprofile)
 - [RelayStatus](#relaystatus)
 - [ReportReason](#reportreason)
@@ -2499,6 +2501,7 @@ UpdateRequired:
 - userChatRelay: [UserChatRelay](#userchatrelay)
 - relayStatus: [RelayStatus](#relaystatus)
 - relayLink: string?
+- relayCap: [RelayCapabilities](#relaycapabilities)
 
 
 ---
@@ -3068,6 +3071,17 @@ NO_SESSION:
 - type: "NO_SESSION"
 
 
+---
+
+## PublicGroupAccess
+
+**Record type**:
+- groupWebPage: string?
+- groupDomain: string?
+- domainWebPage: bool
+- allowEmbedding: bool
+
+
 ---
 
 ## PublicGroupData
@@ -3084,6 +3098,7 @@ NO_SESSION:
 - groupType: [GroupType](#grouptype)
 - groupLink: string
 - publicGroupId: string
+- publicGroupAccess: [PublicGroupAccess](#publicgroupaccess)?
 
 
 ---
@@ -3341,6 +3356,14 @@ ParseError:
 - parseError: string
 
 
+---
+
+## RelayCapabilities
+
+**Record type**:
+- baseWebUrl: string?
+
+
 ---
 
 ## RelayProfile

bots/src/API/Docs/Types.hs

@@ -327,6 +327,7 @@ chatTypesDocsData =
     (sti @Profile, STRecord, "", [], "", ""),
     (sti @ProxyClientError, STUnion, "Proxy", [], "", ""),
     (sti @ProxyError, STUnion, "", [], "", ""),
+    (sti @PublicGroupAccess, STRecord, "", [], "", ""),
     (sti @PublicGroupData, STRecord, "", [], "", ""),
     (sti @PublicGroupProfile, STRecord, "", [], "", ""),
     (sti @RatchetSyncState, STEnum, "RS", [], "", ""),
@@ -338,6 +339,7 @@ chatTypesDocsData =
     (sti @RcvFileTransfer, STRecord, "", [], "", ""),
     (sti @RcvGroupEvent, STUnion, "RGE", [], "", ""),
     (sti @RcvMsgError, STUnion, "RME", [], "", ""),
+    (sti @RelayCapabilities, STRecord, "", [], "", ""),
     (sti @RelayProfile, STRecord, "", [], "", ""),
     (sti @RelayStatus, STEnum, "RS", [], "", ""),
     (sti @ReportReason, STEnum' (dropPfxSfx "RR" ""), "", ["RRUnknown"], "", ""),
@@ -546,6 +548,7 @@ deriving instance Generic PreparedGroup
 deriving instance Generic Profile
 deriving instance Generic ProxyClientError
 deriving instance Generic ProxyError
+deriving instance Generic PublicGroupAccess
 deriving instance Generic PublicGroupData
 deriving instance Generic PublicGroupProfile
 deriving instance Generic RatchetSyncState
@@ -557,6 +560,7 @@ deriving instance Generic RcvFileStatus
 deriving instance Generic RcvFileTransfer
 deriving instance Generic RcvGroupEvent
 deriving instance Generic RcvMsgError
+deriving instance Generic RelayCapabilities
 deriving instance Generic RelayProfile
 deriving instance Generic RelayStatus
 deriving instance Generic ReportReason

packages/simplex-chat-client/types/typescript/src/types.ts

@@ -2776,6 +2776,7 @@ export interface GroupRelay {
   userChatRelay: UserChatRelay
   relayStatus: RelayStatus
   relayLink?: string
+  relayCap: RelayCapabilities
 }
 
 export type GroupRootKey = GroupRootKey.Private | GroupRootKey.Public
@@ -3356,6 +3357,13 @@ export namespace ProxyError {
   }
 }
 
+export interface PublicGroupAccess {
+  groupWebPage?: string
+  groupDomain?: string
+  domainWebPage: boolean
+  allowEmbedding: boolean
+}
+
 export interface PublicGroupData {
   publicMemberCount: number // int64
 }
@@ -3364,6 +3372,7 @@ export interface PublicGroupProfile {
   groupType: GroupType
   groupLink: string
   publicGroupId: string
+  publicGroupAccess?: PublicGroupAccess
 }
 
 export type RCErrorType = 
@@ -3752,6 +3761,10 @@ export namespace RcvMsgError {
   }
 }
 
+export interface RelayCapabilities {
+  baseWebUrl?: string
+}
+
 export interface RelayProfile {
   displayName: string
   fullName: string

packages/simplex-chat-python/src/simplex_chat/types/_types.py

@@ -1949,6 +1949,7 @@ class GroupRelay(TypedDict):
     userChatRelay: "UserChatRelay"
     relayStatus: "RelayStatus"
     relayLink: NotRequired[str]
+    relayCap: "RelayCapabilities"
 
 class GroupRootKey_private(TypedDict):
     type: Literal["private"]
@@ -2356,6 +2357,12 @@ ProxyError = ProxyError_PROTOCOL | ProxyError_BROKER | ProxyError_BASIC_AUTH | P
 
 ProxyError_Tag = Literal["PROTOCOL", "BROKER", "BASIC_AUTH", "NO_SESSION"]
 
+class PublicGroupAccess(TypedDict):
+    groupWebPage: NotRequired[str]
+    groupDomain: NotRequired[str]
+    domainWebPage: bool
+    allowEmbedding: bool
+
 class PublicGroupData(TypedDict):
     publicMemberCount: int  # int64
 
@@ -2363,6 +2370,7 @@ class PublicGroupProfile(TypedDict):
     groupType: "GroupType"
     groupLink: str
     publicGroupId: str
+    publicGroupAccess: NotRequired["PublicGroupAccess"]
 
 class RCErrorType_internal(TypedDict):
     type: Literal["internal"]
@@ -2631,6 +2639,9 @@ RcvMsgError = RcvMsgError_dropped | RcvMsgError_parseError
 
 RcvMsgError_Tag = Literal["dropped", "parseError"]
 
+class RelayCapabilities(TypedDict):
+    baseWebUrl: NotRequired[str]
+
 class RelayProfile(TypedDict):
     displayName: str
     fullName: str

plans/2026-05-25-channel-web-preview.md

@@ -0,0 +1,596 @@
+# Channel Web Preview
+
+## Context
+
+SimpleX channels are public - anybody with the link to join and chat relays rebroadcasting the messages can see content. To grow channels, owners need a public web preview (like Telegram's `t.me/s/channelname`) showing the last 50 messages. This lets potential subscribers browse before joining.
+
+The relay already stores all messages in its database. The web preview is a periodic read-and-render loop that writes JSON files served by Caddy, with CORS controlling which domains can embed the preview.
+
+This feature integrates with the `.simplex` namespace (ENS-based names resolving to channel links). A channel's registered domain (`groupDomain`) lives in `PublicGroupAccess` inside `PublicGroupProfile` and is disseminated with the profile. On-chain verification of the domain is deferred until RSLV resolution protocol ships.
+
+## Architecture
+
+```
+simplex-chat CLI (--relay --web-json-dir=... --web-base-url=...)
+  ├── Main chat loop (existing)
+  ├── Relay logic (existing, gated by --relay)
+  └── Web preview thread (new, gated by relayWebOptions)
+        ├── Periodic: load publishable groups → render JSON → write files
+        └── Regenerate Caddy CORS config → caddy reload
+
+Caddy (operator-configured)
+  ├── Serves JSON at <baseWebUrl>/<publicGroupId>.json
+  └── Imports generated CORS config file
+
+Channel page (static HTML+JS, hosted by owner or on GitHub)
+  ├── Fetches JSON from relay(s) with fallback
+  └── Renders messages, shows join button
+```
+
+## Data Model Changes
+
+### 1. Extend `PublicGroupProfile` with domain and web access settings
+
+**File:** `src/Simplex/Chat/Types.hs` (line 796)
+
+Current:
+```haskell
+data PublicGroupProfile = PublicGroupProfile
+  { groupType :: GroupType,
+    groupLink :: ShortLinkContact,
+    publicGroupId :: B64UrlByteString
+  }
+```
+
+New:
+```haskell
+data PublicGroupAccess = PublicGroupAccess
+  { groupWebPage :: Maybe Text, -- channel's web page URL (adds CORS origin)
+    groupDomain :: Maybe Text,  -- domain for this channel (must have link set in domain record in the contract)
+    domainWebPage :: Bool,      -- show on the domain's page (e.g. simplexnetwork.org site for simplex TLD domains, or domain site for web domains)
+    allowEmbeding :: Bool       -- allow embedding from any origin (CORS: *)
+  }
+
+data PublicGroupProfile = PublicGroupProfile
+  { groupType :: GroupType,
+    groupLink :: ShortLinkContact,
+    publicGroupId :: B64UrlByteString,
+    publicGroupAccess :: Maybe PublicGroupAccess -- NEW: web preview settings
+  }
+```
+
+`groupDomain` stores the channel's registered `.simplex` domain name or another supported TLD. It is:
+- Set by the owner after registering a name on-chain
+- Disseminated to all members via `GroupProfile` (nested in `publicGroup`)
+- Used by `simplexnetwork.org/c/<name>` to route to the channel's web preview (for .simplex domain)
+
+JSON instances: TH-derived `$(JQ.deriveJSON defaultJSON ''PublicGroupAccess)`. Existing `$(JQ.deriveJSON defaultJSON ''PublicGroupProfile)` covers the new optional field.
+
+**Migration (SQLite/Postgres):** separate columns, same pattern as `group_type`/`group_link`/`public_group_id`:
+```sql
+ALTER TABLE group_profiles ADD COLUMN group_web_page TEXT;
+ALTER TABLE group_profiles ADD COLUMN group_domain TEXT;
+ALTER TABLE group_profiles ADD COLUMN domain_web_page INTEGER;
+ALTER TABLE group_profiles ADD COLUMN allow_embedding INTEGER;
+ALTER TABLE group_profiles ADD COLUMN group_domain_verified_at TEXT;
+```
+
+`group_domain_verified_at` is relay-local verification state (nullable timestamp, NULL = unverified).
+
+**Store changes:**
+
+`src/Simplex/Chat/Store/Shared.hs` line 693 - new constructor alongside `toPublicGroupProfile`:
+```haskell
+toPublicGroupAccess :: Maybe Text -> Maybe Text -> Maybe BoolInt -> Maybe BoolInt -> Maybe PublicGroupAccess
+toPublicGroupAccess groupWebPage groupDomain domainWebPage_ allowEmbeding_
+  | isJust groupWebPage || isJust groupDomain || fromBI domainWebPage_ || fromBI allowEmbeding_ =
+      Just PublicGroupAccess {groupWebPage, groupDomain, domainWebPage = fromBI domainWebPage_, allowEmbeding = fromBI allowEmbeding_}
+  | otherwise = Nothing
+  where fromBI = maybe False unBI
+```
+
+Extend `toPublicGroupProfile` to accept and pass through `Maybe PublicGroupAccess`.
+
+`GroupInfoRow` type (line 668) gains columns for: `group_web_page`, `group_domain`, `domain_web_page`, `allow_embedding`, `group_domain_verified_at`.
+
+`src/Simplex/Chat/Store/Groups.hs`:
+- INSERT (line 367): add all new columns
+- SELECT (line 2375): add `gp.group_web_page`, `gp.group_domain`, `gp.domain_web_page`, `gp.allow_embedding`, `gp.group_domain_verified_at`
+- UPDATE (line 1922): include new columns in `updateGroupProfile_`
+
+### 2. `RelayCapabilities` record, extend `XGrpRelayAcpt`, new `XGrpRelayCap`
+
+**File:** `src/Simplex/Chat/Protocol.hs`
+
+New record for relay capabilities (extensible for future fields):
+```haskell
+data RelayCapabilities = RelayCapabilities
+  { baseWebUrl :: Maybe Text
+  }
+```
+
+TH-derived JSON. All fields optional so old relays produce `{}` and new fields are backward compatible.
+
+**`XGrpRelayAcpt`** - carries capabilities at acceptance time:
+
+Current (line 444): `XGrpRelayAcpt :: ShortLinkContact -> ChatMsgEvent 'Json`
+New: `XGrpRelayAcpt :: ShortLinkContact -> RelayCapabilities -> ChatMsgEvent 'Json`
+
+Parsing: `XGrpRelayAcpt_ -> XGrpRelayAcpt <$> p "relayLink" <*> (p "relayCap" <|> pure defaultRelayCap)`
+Encoding: `XGrpRelayAcpt relayLink cap -> o ["relayLink" .= relayLink, "relayCap" .= cap]`
+Backward compatible: old relays omit `relayCap`, parsed as default (all `Nothing`).
+
+**`XGrpRelayCap`** - new message for ongoing capability updates:
+
+```haskell
+XGrpRelayCap :: RelayCapabilities -> ChatMsgEvent 'Json
+```
+
+Tag: `"x.grp.relay.cap"`
+Parsing: `XGrpRelayCap_ -> XGrpRelayCap <$> p "relayCap"`
+Encoding: `XGrpRelayCap cap -> o ["relayCap" .= cap]`
+
+Sent by relay to owner only when capabilities change (not periodic). Relay detects change by comparing current config against persisted state on startup.
+
+### 3. Store `baseWebUrl` per relay
+
+**File:** `src/Simplex/Chat/Operators.hs` (line 278)
+
+Current:
+```haskell
+data GroupRelay = GroupRelay
+  { groupRelayId :: Int64,
+    groupMemberId :: Int64,
+    userChatRelay :: UserChatRelay,
+    relayStatus :: RelayStatus,
+    relayLink :: Maybe ShortLinkContact
+  }
+```
+
+Add: `relayCap :: Maybe RelayCapabilities`
+
+Stored as separate columns (same pattern as `PublicGroupAccess`):
+**Migration:** `ALTER TABLE group_relays ADD COLUMN base_web_url TEXT`
+
+`relayCap` constructed from columns: `Just RelayCapabilities {baseWebUrl}` when any capability column is non-NULL, `Nothing` otherwise.
+
+**Handlers in `src/Simplex/Chat/Library/Subscriber.hs`:**
+- `XGrpRelayAcpt` (line 770): store `RelayCapabilities` in relay record on acceptance
+- `XGrpRelayCap` (new handler): update `RelayCapabilities` in relay record; only accepted from relay members (`isRelay m`), owner receives
+
+**Relay-side persistence:** relay persists its current `RelayCapabilities` (derived from `RelayWebOptions`) so it can detect config changes on restart. On startup, if persisted capabilities differ from config, relay sends `XGrpRelayCap` to all group owners it serves.
+
+### 4. CLI options for web preview
+
+**File:** `src/Simplex/Chat/Options.hs`
+
+New record bundling all web preview options:
+```haskell
+data RelayWebOptions = RelayWebOptions
+  { webJsonDir :: FilePath,       -- --web-json-dir: where to write JSON files
+    webBaseUrl :: Text,           -- --web-base-url: public URL prefix (sent in XGrpRelayAcpt)
+    webCorsFile :: FilePath,      -- --web-cors-file: generated Caddy CORS config path
+    webUpdateInterval :: Int      -- --web-update-interval: seconds (default 300)
+  }
+```
+
+Add as a proper field in `CoreChatOpts`:
+```haskell
+data CoreChatOpts = CoreChatOpts
+  { ...existing...,
+    relayWebOptions :: Maybe RelayWebOptions
+  }
+```
+
+Parsed from CLI: when `--web-json-dir` is provided, all other `--web-*` flags are required. `Nothing` when no web preview flags are set. Only meaningful when `--relay` is also set.
+
+### 5. Web preview thread startup
+
+**File:** `src/Simplex/Chat/Core.hs` (line 74)
+
+Current:
+```haskell
+runSimplexChat ... = do
+    a1 <- runReaderT (startChatController True True) cc
+    when (chatRelay && not testView) $ askCreateRelayAddress cc u
+    forM_ (postStartHook chatHooks) ($ cc)
+    a2 <- async $ chat u cc
+    waitEither_ a1 a2
+```
+
+Add web preview thread as a third async when config is present:
+```haskell
+runSimplexChat ... = do
+    a1 <- runReaderT (startChatController True True) cc
+    when (chatRelay && not testView) $ askCreateRelayAddress cc u
+    forM_ (postStartHook chatHooks) ($ cc)
+    a2 <- async $ chat u cc
+    case relayWebOptions coreOptions of
+      Nothing -> waitEither_ a1 a2
+      Just webOpts -> do
+        a3 <- async $ webPreviewThread webOpts cc
+        void $ waitAnyCancel [a1, a2, a3]
+```
+
+## New Types for JSON Serialization
+
+**File:** new module `src/Simplex/Chat/Web/Preview.hs`
+
+### Reuse as-is (existing ToJSON instances)
+
+- `GroupProfile` (Types.hs:803) - channel metadata (displayName, fullName, shortDescr, description, image, publicGroup incl. groupDomain)
+- `MsgContent` (Protocol.hs:689) - tagged union: MCText, MCLink, MCImage, MCVideo, etc.
+- `LinkPreview` (Protocol.hs:256) - `{uri, title, description, image, content}`
+- `FormattedText` / `MarkdownList` (Markdown.hs:133/139) - parsed markdown
+- `QuotedMsg` / `MsgRef` (Protocol.hs:589) - quoted message context
+- `MsgMentions` = `Map MemberName CIMention` (Messages.hs:264)
+- `CIMention` (Messages.hs:272) - `{memberId, memberRef}`
+- `CIReactionCount` (Messages.hs:338) - `{reaction, userReacted, totalReacted}`
+
+### New types
+
+```haskell
+data WebFileInfo = WebFileInfo
+  { fileName :: String,
+    fileSize :: Integer
+  }
+
+data WebMemberProfile = WebMemberProfile
+  { memberId :: MemberId,
+    displayName :: Text,
+    image :: Maybe ImageData
+  }
+
+data WebMessage = WebMessage
+  { sender :: Maybe MemberId,         -- Nothing for CIChannelRcv (forwarded-from-channel)
+    ts :: UTCTime,
+    content :: MsgContent,
+    formattedText :: Maybe MarkdownList,
+    file :: Maybe WebFileInfo,
+    quote :: Maybe QuotedMsg,
+    mentions :: Map MemberName CIMention,
+    reactions :: [CIReactionCount],
+    forwarded :: Maybe CIForwardedFrom,
+    edited :: Bool
+  }
+
+data WebChannelPreview = WebChannelPreview
+  { channel :: GroupProfile,       -- NOTE: render loop strips groupDomain until verified
+    subscriberCount :: Maybe Int,
+    members :: [WebMemberProfile],
+    messages :: [WebMessage],
+    updatedAt :: UTCTime
+  }
+```
+
+TH-derived JSON for `WebFileInfo`, `WebMemberProfile`, `WebMessage`, `WebChannelPreview`.
+
+## Render Loop
+
+**File:** new module `src/Simplex/Chat/Web.hs`
+
+Pattern from directory service's `updateListingsThread_` (Service.hs:185-194).
+
+```haskell
+webPreviewThread :: RelayWebOptions -> ChatController -> IO ()
+webPreviewThread opts cc = forever $ do
+    u_ <- readTVarIO $ currentUser cc
+    forM_ u_ $ \user -> do
+      groups <- getWebPublishGroups cc user
+      corsEntries <- forM groups $ \gInfo -> do
+        renderGroupPreview opts cc user gInfo
+        pure (corsEntry gInfo)
+      writeCorsConfig opts corsEntries
+    threadDelay (webUpdateInterval opts * 1_000_000)
+```
+
+### Loading groups
+
+New store function `getWebPublishGroups`:
+```sql
+SELECT ... FROM groups g
+JOIN group_profiles gp ON g.group_profile_id = gp.group_profile_id
+WHERE gp.group_web_page IS NOT NULL
+  AND g.user_id = ?
+```
+
+Returns `[GroupInfo]`. For each, call `getGroupChat` with `CPLast 50` (Store/Messages.hs:1436) to get chat items.
+
+### Converting CChatItem to WebMessage
+
+For each `CChatItem SMDRcv (ChatItem {chatDir, meta, content, mentions, formattedText, quotedItem, reactions, file})`:
+
+1. **Skip if:**
+   - `itemDeleted meta` is `Just _`
+   - `itemTimed meta` is `Just _`
+   - `content` is not `CIRcvMsgContent mc` (skip `CIRcvGroupEvent`, `CIRcvIntegrityError`, etc.)
+   - `mc` is `MCReport` or `MCUnknown`
+
+2. **Extract sender:**
+   - `CIGroupRcv member` -> `Just (memberId member)`, collect member into profiles array
+   - `CIChannelRcv` -> `Nothing` (channel-forwarded message, no individual sender)
+
+3. **Extract file info:**
+   - `file :: Maybe (CIFile 'MDRcv)` has `fileName :: String`, `fileSize :: Integer`
+   - Strip `fileSource`, `fileStatus`, `fileProtocol` (download metadata irrelevant for web)
+
+4. **Build WebMessage:**
+   ```haskell
+   WebMessage
+     { sender = senderMemberId
+     , ts = itemTs meta
+     , content = mc
+     , formattedText = formattedText
+     , file = (\f -> WebFileInfo (fileName f) (fileSize f)) <$> file
+     , quote = quotedItem  -- QuotedMsg reused directly
+     , mentions = mentions
+     , reactions = reactions
+     , forwarded = itemForwarded meta
+     , edited = itemEdited meta
+     }
+   ```
+
+5. **Collect unique senders** into `[WebMemberProfile]` from `GroupMember` records in `CIGroupRcv`.
+
+Also include `CIGroupSnd` items (relay's own sent messages, if any - unlikely but possible for admin announcements).
+
+### Filtering unverified domains
+
+Before serializing, the render loop strips `groupDomain` from the `PublicGroupAccess` included in the profile when not verified:
+
+```haskell
+stripUnverifiedDomain :: Maybe UTCTime -> GroupProfile -> GroupProfile
+stripUnverifiedDomain verifiedAt gp = case verifiedAt of
+  Just _ -> gp  -- domain verified, include as-is
+  Nothing -> gp {publicGroup = clearDomain <$> publicGroup gp}
+  where
+    clearDomain pgp = pgp {publicGroupAccess = clearAccess <$> publicGroupAccess pgp}
+    clearAccess acc = acc {groupDomain = ""}  -- or strip the access record entirely
+```
+
+The `group_domain_verified_at` timestamp is loaded alongside the group info. Until RSLV ships, this column is always NULL, so all domains are stripped from web export.
+
+`domainWebPage` in CORS config is also gated on verified domain - unverified means no domain-site origin in CORS.
+
+### Writing JSON
+
+- Serialize `WebChannelPreview` to JSON via `Data.Aeson.encode`
+- Write atomically (write to temp, rename) to `<webJsonDir>/<publicGroupId>.json`
+- `publicGroupId` from `PublicGroupProfile` (base64url-encoded, existing field)
+
+### Generating Caddy CORS config
+
+Write a single file with Caddy `map` directive:
+
+```caddy
+map {path} {cors_origin} {
+    /<publicGroupId1>.json "https://owner-domain.com"
+    /<publicGroupId2>.json "*"
+    default ""
+}
+header /*.json Access-Control-Allow-Origin {cors_origin}
+header /*.json Access-Control-Allow-Methods "GET, OPTIONS"
+```
+
+CORS origin derivation from `PublicGroupAccess`:
+- `allowEmbeding = True` -> `*`
+- `groupWebPage = Just url` -> extract origin from URL (+ domain site origin if `domainWebPage` and domain verified)
+- `groupWebPage = Nothing, domainWebPage = True` -> domain site origin only (when domain is verified)
+- No web page, no embedding, no domain page -> omit from config
+
+After writing, run `caddy reload` if file content changed (compare hash before/after).
+
+## Namespace Integration
+
+`groupDomain` ships now in the profile (inside `PublicGroupAccess`). What's deferred is on-chain verification (RSLV protocol).
+
+### What ships now
+
+1. **`groupDomain :: Text` in `PublicGroupAccess`** - owner sets the registered domain, disseminated to all members
+2. **`domainWebPage :: Bool` in `PublicGroupAccess`** - flag stored but has no effect until domain is verified
+3. **Relay strips `groupDomain` from web export** - no verification means domain is cleared in JSON, no domain-site CORS origin
+
+### What ships with RSLV
+
+1. **RSLV protocol** - relay queries name servers via SMP proxy to verify domain ownership
+2. **`domainWebPage` becomes functional** - enables domain-site hosting (e.g. `simplexnetwork.org/c/<name>`) for verified domains
+3. **In-app resolution** - `#name` markdown (already parsed by namespace branch) resolves and connects
+
+### Verification flow (relay-side)
+
+When owner updates profile with `groupDomain`:
+
+1. **Trigger:** Relay receives profile update on owner's connection containing `groupDomain` field
+2. **Initiate:** Relay sends `RSLV <namehash>` through SMP proxy (async, on the same owner connection context)
+3. **Pending state:** `group_domain_verified_at = NULL` in DB. Web export excludes domain while pending.
+4. **Resolution arrives:** `NAME <record>` agent event arrives on the owner's connection (continuation bound to the connection that sent the profile update)
+5. **Verify:** Check if `channelLinks` in the NAME response includes this group's `groupLink`
+6. **Store result:** Set `group_domain_verified_at = <current_time>` on success, leave NULL on failure
+7. **Effect:** Web render loop includes domain in JSON and enables domain-site CORS only when `group_domain_verified_at IS NOT NULL`
+
+Re-verification: periodic (e.g. daily or on each web update cycle) to catch expired/transferred domains. Clear `group_domain_verified_at` when re-verification fails.
+
+### What the namespace branch already provides
+
+- `SimplexNameInfo {nameType, namespace, domain, subDomain}` in Markdown.hs
+- `SimplexName` variant in `Format` ADT
+- Parser for `#name` / `#name.simplex` / `:name.simplex` syntax
+- Forward-compatibility alerts in Kotlin/Swift UI (shows "requires newer app" until resolution is implemented)
+
+## UI Changes (Kotlin/Swift)
+
+### Kotlin types
+
+**File:** `apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/model/ChatModel.kt`
+
+```kotlin
+@Serializable
+data class PublicGroupAccess(
+    val groupWebPage: String? = null,
+    val groupDomain: String? = null,
+    val domainWebPage: Boolean = false,
+    val allowEmbeding: Boolean = false
+)
+
+// Extend existing PublicGroupProfile (currently at line 2213):
+@Serializable
+data class PublicGroupProfile(
+    val groupType: GroupType,
+    val groupLink: String,
+    val publicGroupId: String,
+    val publicGroupAccess: PublicGroupAccess? = null  // NEW
+)
+
+@Serializable
+data class RelayCapabilities(
+    val baseWebUrl: String? = null
+)
+
+// Extend existing GroupRelay:
+@Serializable
+data class GroupRelay(
+    ...existing fields...,
+    val relayCap: RelayCapabilities? = null  // NEW
+)
+```
+
+### Owner: Channel info page
+
+**File:** `GroupChatInfoView.kt` (around line 604-606)
+
+After existing `ChannelLinkButton(manageGroupLink)`:
+```kotlin
+ChannelWebPageButton(openChannelWebPage)  // owner only
+```
+
+New nav destination opens `ChannelWebPageView`.
+
+### Owner: Channel web page screen
+
+**File:** new `apps/multiplatform/.../views/chat/group/ChannelWebPageView.kt`
+
+- Text field: web page URL (`groupWebPage`)
+- Text field: domain (`groupDomain`)
+- Toggle: allow embedding (`allowEmbeding`)
+- Toggle: show on domain's page (`domainWebPage`) - stored but inert until RSLV ships
+- Section: embed snippet (read-only, auto-generated from relay `baseWebUrl` values + `publicGroupId`)
+- Save button -> `apiUpdateGroup` with updated `GroupProfile`
+
+### Subscriber: Channel info page
+
+In the top section (around line 607-614), after channel link QR:
+```kotlin
+val webPageUrl = groupInfo.groupProfile.publicGroup?.publicGroupAccess?.groupWebPage
+if (webPageUrl != null) {
+    WebPageLinkRow(webPageUrl)  // clickable, opens browser
+}
+```
+
+## Build Configuration
+
+Web preview code compiles into the main `simplex-chat` library (not conditional). The thread only starts when `relayWebOptions` is set in `CoreChatOpts`. Mobile apps never set this.
+
+No cabal flag needed - the thread startup is gated by `Maybe RelayWebOptions` at runtime (same pattern as `chatRelay` gating relay behavior).
+
+## Caddy Setup (operator documentation)
+
+Main Caddyfile (operator writes once):
+```caddy
+relay.example.com {
+    import /etc/caddy/simplex-cors.conf
+    handle /preview/* {
+        root * /var/lib/simplex/web/preview
+        file_server
+    }
+}
+```
+
+Relay CLI invocation:
+```
+simplex-chat --relay \
+  --web-json-dir /var/lib/simplex/web/preview \
+  --web-base-url https://relay.example.com/preview \
+  --web-cors-file /etc/caddy/simplex-cors.conf \
+  --web-update-interval 300
+```
+
+## Channel Page and Embed Code
+
+### Embed snippet (shown to owner)
+
+The "Channel web page" screen auto-generates this from the channel's relay `baseWebUrl` values and `publicGroupId`. Owner copies it into their page:
+
+```html
+<div id="simplex-channel"
+  data-channel-id="<publicGroupId>"
+  data-relays="<baseWebUrl1>,<baseWebUrl2>">
+</div>
+<script src="https://simplex.chat/channel-preview.js"></script>
+```
+
+Example with real values:
+```html
+<div id="simplex-channel"
+  data-channel-id="a1b2c3d4"
+  data-relays="https://relay1.example.com/preview,https://relay2.example.com/preview">
+</div>
+<script src="https://simplex.chat/channel-preview.js"></script>
+```
+
+The script fetches `<relay>/a1b2c3d4.json`, renders the preview into the `div`. Tries relays in order, falls back on failure. The owner's domain must match the CORS origin configured by the relay (derived from `groupWebPage`), or `allowEmbeding` must be `True` for `*`.
+
+For iframe embedding (when allowed), the snippet is simpler - just an iframe pointing to the owner's hosted channel page.
+
+### Channel page (static JS)
+
+Separate repo or folder. `channel-preview.js` + minimal CSS:
+- Reads config from `data-` attributes on the container div
+- Fetches JSON from relays with fallback (try first, fall back to second)
+- Renders: channel header (name, avatar, description, subscriber count), message list (text with FormattedText markdown, link previews, file indicators, reactions, quotes)
+- Join button: `simplex://` deep link on mobile, QR code on desktop
+- Reuses directory page's markdown rendering approach
+
+## Files to Create/Modify
+
+### New files
+- `src/Simplex/Chat/Web/Preview.hs` - types: `WebChannelPreview`, `WebMessage`, `WebFileInfo`, `WebMemberProfile`
+- `src/Simplex/Chat/Web.hs` - render loop, JSON writing, Caddy config generation
+- `apps/multiplatform/.../views/chat/group/ChannelWebPageView.kt`
+- `apps/ios/Shared/Views/Chat/Group/ChannelWebPageView.swift`
+- Migration files (SQLite + Postgres): `group_web_page`, `group_domain`, `domain_web_page`, `allow_embedding`, `group_domain_verified_at` in group_profiles; `base_web_url` in group_relays
+- Channel page static site (separate repo/folder)
+
+### Modified files
+- `src/Simplex/Chat/Types.hs` - `PublicGroupAccess` type, extend `PublicGroupProfile` with `publicGroupAccess`
+- `src/Simplex/Chat/Protocol.hs` - `RelayCapabilities` record, extend `XGrpRelayAcpt`, add `XGrpRelayCap`
+- `src/Simplex/Chat/Options.hs` - `RelayWebOptions` record, `relayWebOptions :: Maybe RelayWebOptions` in `CoreChatOpts`
+- `src/Simplex/Chat/Core.hs` - start web preview thread in `runSimplexChat`
+- `src/Simplex/Chat/Operators.hs` - `baseWebUrl` in `GroupRelay`
+- `src/Simplex/Chat/Store/Groups.hs` - read/write `PublicGroupAccess` columns; `getWebPublishGroups`
+- `src/Simplex/Chat/Store/Shared.hs` - `toPublicGroupAccess`, extend `toPublicGroupProfile` and `GroupInfoRow`
+- `src/Simplex/Chat/Library/Subscriber.hs` - handle `RelayCapabilities` in `XGrpRelayAcpt` and `XGrpRelayCap`
+- `apps/multiplatform/.../model/ChatModel.kt` - `PublicGroupAccess`, `RelayCapabilities`, `PublicGroupProfile.publicGroupAccess`, `GroupRelay.relayCap`
+- `apps/multiplatform/.../views/chat/group/GroupChatInfoView.kt` - nav link for web page
+- `simplex-chat.cabal` - add `Simplex.Chat.Web.Preview`, `Simplex.Chat.Web` to exposed-modules
+
+## Implementation Order
+
+1. **Data model** - `PublicGroupAccess` in `PublicGroupProfile`, migrations (separate columns), store functions
+2. **Protocol** - `RelayCapabilities`, extend `XGrpRelayAcpt`, add `XGrpRelayCap`, handlers in Subscriber.hs
+3. **CLI options** - `RelayWebOptions` record, `relayWebOptions` field in `CoreChatOpts`
+4. **Web types** - `WebChannelPreview`, `WebMessage`, etc. in new module
+5. **Render loop** - thread startup in Core.hs, periodic JSON generation, Caddy config
+6. **UI (owner)** - "Channel web page" settings screen
+7. **UI (subscriber)** - web page link in channel info
+8. **Channel page** - static HTML+JS template
+9. **Documentation** - operator setup guide
+
+## Verification
+
+1. **Build**: `cabal build simplex-chat` with new modules compiles
+2. **Unit test**: serialize `WebChannelPreview` with sample data, verify JSON matches expected structure
+3. **Integration test**: create channel with `publicGroupAccess` set, run relay with `--web-json-dir`, verify JSON file appears at correct path with correct content
+4. **CORS test**: verify generated config produces correct `Access-Control-Allow-Origin` for configured domains
+5. **UI test**: owner can set web page URL and domain, see embed snippet; subscriber sees clickable link
+6. **Channel page test**: serve static page locally against relay's JSON, verify rendering
+7. **Domain stripping test**: set `groupDomain` on a channel, verify it is stripped from web export JSON (unverified, `group_domain_verified_at IS NULL`)

simplex-chat.cabal

@@ -133,6 +133,7 @@ library
           Simplex.Chat.Store.Postgres.Migrations.M20260429_relay_request_retries
           Simplex.Chat.Store.Postgres.Migrations.M20260507_relay_inactive_at
           Simplex.Chat.Store.Postgres.Migrations.M20260514_relay_request_group_link_index
+          Simplex.Chat.Store.Postgres.Migrations.M20260515_public_group_access
   else
       exposed-modules:
           Simplex.Chat.Archive
@@ -288,6 +289,7 @@ library
           Simplex.Chat.Store.SQLite.Migrations.M20260429_relay_request_retries
           Simplex.Chat.Store.SQLite.Migrations.M20260507_relay_inactive_at
           Simplex.Chat.Store.SQLite.Migrations.M20260514_relay_request_group_link_index
+          Simplex.Chat.Store.SQLite.Migrations.M20260515_public_group_access
   other-modules:
       Paths_simplex_chat
   hs-source-dirs:

src/Simplex/Chat/Library/Commands.hs

@@ -2524,7 +2524,8 @@ processChatCommand vr nm = \case
         -- generate owner key, OwnerAuth signed by root key
         memberId <- MemberId <$> liftIO (encodedRandomBytes gVar 12)
         (memberPrivKey, ownerAuth) <- liftIO $ SL.newOwnerAuth gVar (unMemberId memberId) rootPrivKey
-        let groupProfile' = (groupProfile :: GroupProfile) {publicGroup = Just PublicGroupProfile {groupType = GTChannel, groupLink = sLnk, publicGroupId = B64UrlByteString entityId}}
+        -- TODO [channel web] pass publicGroupAccess from owner's profile
+        let groupProfile' = (groupProfile :: GroupProfile) {publicGroup = Just PublicGroupProfile {groupType = GTChannel, groupLink = sLnk, publicGroupId = B64UrlByteString entityId, publicGroupAccess = Nothing}}
             userData = encodeShortLinkData $ GroupShortLinkData {groupProfile = groupProfile', publicGroupData = Just (PublicGroupData 1)}
             userLinkData = UserContactLinkData UserContactData {direct = False, owners = [ownerAuth], relays = [], userData}
         -- create connection with prepared link (single network call)
@@ -2643,8 +2644,7 @@ processChatCommand vr nm = \case
         Nothing -> throwChatError $ CEContactNotActive ct
   APIAcceptMember groupId gmId role -> withUser $ \user@User {userId} -> do
     (gInfo, m) <- withFastStore $ \db -> (,) <$> getGroupInfo db vr user groupId <*> getGroupMemberById db vr user gmId
-    -- TODO check that user's role is > role, possibly restrict role to only observer and member
-    assertUserGroupRole gInfo GRModerator
+    assertUserGroupRole gInfo $ max GRModerator role
     case memberStatus m of
       GSMemPendingApproval | memberCategory m == GCInviteeMember -> do -- only host can approve
         let GroupInfo {groupProfile = GroupProfile {memberAdmission}} = gInfo

src/Simplex/Chat/Library/Internal.hs

@@ -1048,7 +1048,8 @@ acceptRelayJoinRequestAsync
   cReqInvId
   cReqChatVRange
   relayLink = do
-    let msg = XGrpRelayAcpt relayLink
+    -- TODO [channel web] derive RelayCapabilities from relay config (RelayWebOptions)
+    let msg = XGrpRelayAcpt relayLink defaultRelayCapabilities
     subMode <- chatReadVar subscriptionMode
     vr <- chatVersionRange
     let chatV = vr `peerConnChatVersion` cReqChatVRange

src/Simplex/Chat/Library/Subscriber.hs

@@ -765,9 +765,11 @@ processAgentMessageConn vr user@User {userId} corrId agentConnId agentMessage =
                     -- [async agent commands] no continuation needed, but command should be asynchronous for stability
                     allowAgentConnectionAsync user conn' confId XOk
                 | otherwise -> messageError "x.grp.acpt: memberId is different from expected"
-              XGrpRelayAcpt relayLink
+              XGrpRelayAcpt relayLink relayCap
                 | memberRole' membership == GROwner && isRelay m -> do
-                    withStore' $ \db -> setRelayLinkConfId db m confId relayLink
+                    withStore' $ \db -> do
+                      setRelayLinkConfId db m confId relayLink
+                      updateRelayCapabilities db m relayCap
                     void $ getAgentConnShortLinkAsync user CFGetRelayDataAccept (Just conn') relayLink
                 | otherwise -> messageError "x.grp.relay.acpt: only owner can add relay"
               XGrpRelayReject reason
@@ -1036,6 +1038,10 @@ processAgentMessageConn vr user@User {userId} corrId agentConnId agentMessage =
               XGrpLinkMem p -> Nothing <$ xGrpLinkMem gInfo' m'' conn' p
               XGrpLinkAcpt acceptance role memberId -> Nothing <$ xGrpLinkAcpt gInfo' m'' acceptance role memberId msg brokerTs
               XGrpRelayNew rl -> fmap ctx <$> xGrpRelayNew gInfo' m'' rl
+              XGrpRelayCap relayCap
+                | memberRole' membership == GROwner && isRelay m'' ->
+                    Nothing <$ withStore' (\db -> updateRelayCapabilities db m'' relayCap)
+                | otherwise -> Nothing <$ messageWarning "x.grp.relay.cap: only owner should receive relay capabilities"
               XGrpMemNew memInfo msgScope -> fmap ctx <$> xGrpMemNew gInfo' m'' memInfo msgScope msg brokerTs
               XGrpMemIntro memInfo memRestrictions_ -> Nothing <$ xGrpMemIntro gInfo' m'' memInfo memRestrictions_
               XGrpMemInv memId introInv -> Nothing <$ xGrpMemInv gInfo' m'' memId introInv
@@ -2601,6 +2607,8 @@ processAgentMessageConn vr user@User {userId} corrId agentConnId agentMessage =
 
     xGrpLinkAcpt :: GroupInfo -> GroupMember -> GroupAcceptance -> GroupMemberRole -> MemberId -> RcvMessage -> UTCTime -> CM ()
     xGrpLinkAcpt gInfo@GroupInfo {membership} m acceptance role memberId msg brokerTs
+      | memberRole' m < GRModerator || memberRole' m < role =
+          messageError "x.grp.link.acpt with insufficient member permissions"
       | sameMemberId memberId membership = processUserAccepted
       | otherwise =
           withStore' (\db -> runExceptT $ getGroupMemberByMemberId db vr user gInfo memberId) >>= \case

src/Simplex/Chat/Operators.hs

@@ -46,7 +46,7 @@ import Data.Time (addUTCTime)
 import Data.Time.Clock (UTCTime, nominalDay)
 import Language.Haskell.TH.Syntax (lift)
 import Simplex.Chat.Operators.Conditions
-import Simplex.Chat.Protocol (RelayProfile (..))
+import Simplex.Chat.Protocol (RelayCapabilities (..), RelayProfile (..))
 import Simplex.Chat.Types (ShortLinkContact, User)
 import Simplex.Chat.Types.Shared (RelayStatus)
 import Simplex.Messaging.Agent.Env.SQLite (ServerCfg (..), ServerRoles (..), allRoles)
@@ -280,7 +280,8 @@ data GroupRelay = GroupRelay
     groupMemberId :: Int64,
     userChatRelay :: UserChatRelay,
     relayStatus :: RelayStatus,
-    relayLink :: Maybe ShortLinkContact
+    relayLink :: Maybe ShortLinkContact,
+    relayCap :: RelayCapabilities
   }
   deriving (Eq, Show)
 

src/Simplex/Chat/Protocol.hs

@@ -262,6 +262,14 @@ data LinkContent = LCPage | LCImage | LCVideo {duration :: Maybe Int} | LCUnknow
 data ReportReason = RRSpam | RRContent | RRCommunity | RRProfile | RROther | RRUnknown Text
   deriving (Eq, Show)
 
+data RelayCapabilities = RelayCapabilities
+  { baseWebUrl :: Maybe Text
+  }
+  deriving (Eq, Show)
+
+defaultRelayCapabilities :: RelayCapabilities
+defaultRelayCapabilities = RelayCapabilities {baseWebUrl = Nothing}
+
 $(pure [])
 
 instance FromJSON LinkContent where
@@ -281,6 +289,12 @@ instance ToJSON LinkContent where
 
 $(JQ.deriveJSON defaultJSON ''LinkPreview)
 
+$(JQ.deriveToJSON defaultJSON ''RelayCapabilities)
+
+instance FromJSON RelayCapabilities where
+  parseJSON = $(JQ.mkParseJSON defaultJSON ''RelayCapabilities)
+  omittedField = Just defaultRelayCapabilities
+
 instance StrEncoding ReportReason where
   strEncode = \case
     RRSpam -> "spam"
@@ -441,10 +455,11 @@ data ChatMsgEvent (e :: MsgEncoding) where
   XGrpLinkMem :: Profile -> ChatMsgEvent 'Json
   XGrpLinkAcpt :: GroupAcceptance -> GroupMemberRole -> MemberId -> ChatMsgEvent 'Json
   XGrpRelayInv :: GroupRelayInvitation -> ChatMsgEvent 'Json
-  XGrpRelayAcpt :: ShortLinkContact -> ChatMsgEvent 'Json
+  XGrpRelayAcpt :: ShortLinkContact -> RelayCapabilities -> ChatMsgEvent 'Json
   XGrpRelayTest :: ByteString -> Maybe ByteString -> ChatMsgEvent 'Json
   XGrpRelayNew :: ShortLinkContact -> ChatMsgEvent 'Json
   XGrpRelayReject :: RelayRejectionReason -> ChatMsgEvent 'Json
+  XGrpRelayCap :: RelayCapabilities -> ChatMsgEvent 'Json
   XGrpMemNew :: MemberInfo -> Maybe MsgScope -> ChatMsgEvent 'Json
   XGrpMemIntro :: MemberInfo -> Maybe MemberRestrictions -> ChatMsgEvent 'Json
   XGrpMemInv :: MemberId -> IntroInvitation -> ChatMsgEvent 'Json
@@ -991,6 +1006,7 @@ data CMEventTag (e :: MsgEncoding) where
   XGrpRelayTest_ :: CMEventTag 'Json
   XGrpRelayNew_ :: CMEventTag 'Json
   XGrpRelayReject_ :: CMEventTag 'Json
+  XGrpRelayCap_ :: CMEventTag 'Json
   XGrpMemNew_ :: CMEventTag 'Json
   XGrpMemIntro_ :: CMEventTag 'Json
   XGrpMemInv_ :: CMEventTag 'Json
@@ -1050,6 +1066,7 @@ instance MsgEncodingI e => StrEncoding (CMEventTag e) where
     XGrpRelayTest_ -> "x.grp.relay.test"
     XGrpRelayNew_ -> "x.grp.relay.new"
     XGrpRelayReject_ -> "x.grp.relay.reject"
+    XGrpRelayCap_ -> "x.grp.relay.cap"
     XGrpMemNew_ -> "x.grp.mem.new"
     XGrpMemIntro_ -> "x.grp.mem.intro"
     XGrpMemInv_ -> "x.grp.mem.inv"
@@ -1110,6 +1127,7 @@ instance StrEncoding ACMEventTag where
         "x.grp.relay.test" -> XGrpRelayTest_
         "x.grp.relay.new" -> XGrpRelayNew_
         "x.grp.relay.reject" -> XGrpRelayReject_
+        "x.grp.relay.cap" -> XGrpRelayCap_
         "x.grp.mem.new" -> XGrpMemNew_
         "x.grp.mem.intro" -> XGrpMemIntro_
         "x.grp.mem.inv" -> XGrpMemInv_
@@ -1162,10 +1180,11 @@ toCMEventTag msg = case msg of
   XGrpLinkMem _ -> XGrpLinkMem_
   XGrpLinkAcpt {} -> XGrpLinkAcpt_
   XGrpRelayInv _ -> XGrpRelayInv_
-  XGrpRelayAcpt _ -> XGrpRelayAcpt_
+  XGrpRelayAcpt {} -> XGrpRelayAcpt_
   XGrpRelayTest {} -> XGrpRelayTest_
   XGrpRelayNew _ -> XGrpRelayNew_
   XGrpRelayReject _ -> XGrpRelayReject_
+  XGrpRelayCap _ -> XGrpRelayCap_
   XGrpMemNew {} -> XGrpMemNew_
   XGrpMemIntro _ _ -> XGrpMemIntro_
   XGrpMemInv _ _ -> XGrpMemInv_
@@ -1318,7 +1337,8 @@ appJsonToCM AppMessageJson {v, msgId, event, params} = do
       XGrpLinkMem_ -> XGrpLinkMem <$> p "profile"
       XGrpLinkAcpt_ -> XGrpLinkAcpt <$> p "acceptance" <*> p "role" <*> p "memberId"
       XGrpRelayInv_ -> XGrpRelayInv <$> p "groupRelayInvitation"
-      XGrpRelayAcpt_ -> XGrpRelayAcpt <$> p "relayLink"
+      XGrpRelayAcpt_ -> XGrpRelayAcpt <$> p "relayLink" <*> (fromMaybe defaultRelayCapabilities <$> opt "relayCap")
+      XGrpRelayCap_ -> XGrpRelayCap <$> p "relayCap"
       XGrpRelayTest_ -> do
         B64UrlByteString challenge <- p "challenge"
         sig_ <- fmap (\(B64UrlByteString s) -> s) <$> opt "signature"
@@ -1390,7 +1410,8 @@ chatToAppMessage chatMsg@ChatMessage {chatVRange, msgId, chatMsgEvent} = case en
       XGrpLinkMem profile -> o ["profile" .= profile]
       XGrpLinkAcpt acceptance role memberId -> o ["acceptance" .= acceptance, "role" .= role, "memberId" .= memberId]
       XGrpRelayInv groupRelayInv -> o ["groupRelayInvitation" .= groupRelayInv]
-      XGrpRelayAcpt relayLink -> o ["relayLink" .= relayLink]
+      XGrpRelayAcpt relayLink relayCap -> o ["relayLink" .= relayLink, "relayCap" .= relayCap]
+      XGrpRelayCap relayCap -> o ["relayCap" .= relayCap]
       XGrpRelayTest challenge sig_ -> o $
         ("signature" .=? (B64UrlByteString <$> sig_))
         ["challenge" .= B64UrlByteString challenge]

src/Simplex/Chat/Store/Connections.hs

@@ -139,6 +139,7 @@ getConnectionEntity db vr user@User {userId, userContactId} agentConnId = do
                 SELECT
                   -- GroupInfo
                   g.group_id, g.local_display_name, gp.display_name, gp.full_name, gp.short_descr, g.local_alias, gp.description, gp.image, gp.group_type, gp.group_link, gp.public_group_id,
+                  gp.group_web_page, gp.group_domain, gp.domain_web_page, gp.allow_embedding,
                   g.enable_ntfs, g.send_rcpts, g.favorite, gp.preferences, gp.member_admission,
                   g.created_at, g.updated_at, g.chat_ts, g.user_member_profile_sent_at,
                   g.conn_full_link_to_connect, g.conn_short_link_to_connect, g.conn_link_prepared_connection, g.conn_link_started_connection, g.welcome_shared_msg_id, g.request_shared_msg_id,

src/Simplex/Chat/Store/Groups.hs

@@ -89,6 +89,7 @@ module Simplex.Chat.Store.Groups
     updateRelayStatusFromTo,
     setRelayLinkAccepted,
     setRelayLinkConfId,
+    updateRelayCapabilities,
     getRelayConfId,
     updateRelayMemberData,
     setGroupInProgressDone,
@@ -367,10 +368,11 @@ createNewGroup db vr user@User {userId} groupProfile incognitoProfile useRelays
           INSERT INTO group_profiles
             (display_name, full_name, short_descr, description, image,
              group_type, group_link, public_group_id,
+             group_web_page, group_domain, domain_web_page, allow_embedding,
              user_id, preferences, member_admission, created_at, updated_at)
-          VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?)
+          VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)
         |]
-        ((displayName, fullName, shortDescr, description, image, groupType_, groupLink_, publicGroupId_)
+        ((displayName, fullName, shortDescr, description, image, groupType_, groupLink_, publicGroupId_) :. publicGroupAccessRow publicGroup
           :. (userId, groupPreferences, memberAdmission, currentTs, currentTs))
       profileId <- insertedRowId db
       DB.execute
@@ -868,10 +870,11 @@ createGroup_ db userId groupProfile prepared business useRelays relayOwnStatus p
           INSERT INTO group_profiles
             (display_name, full_name, short_descr, description, image,
              group_type, group_link, public_group_id,
+             group_web_page, group_domain, domain_web_page, allow_embedding,
              user_id, preferences, member_admission, created_at, updated_at)
-          VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?)
+          VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)
         |]
-        ((displayName, fullName, shortDescr, description, image, groupType_, groupLink_, publicGroupId_)
+        ((displayName, fullName, shortDescr, description, image, groupType_, groupLink_, publicGroupId_) :. publicGroupAccessRow publicGroup
           :. (userId, groupPreferences, memberAdmission, currentTs, currentTs))
       profileId <- insertedRowId db
       DB.execute
@@ -1343,15 +1346,16 @@ groupRelayQuery =
   [sql|
     SELECT gr.group_relay_id, gr.group_member_id,
            cr.chat_relay_id, cr.address, cr.display_name, cr.full_name, cr.short_descr, cr.image, cr.domains, cr.preset, cr.tested, cr.enabled, cr.deleted,
-           gr.relay_status, gr.relay_link
+           gr.relay_status, gr.relay_link, gr.base_web_url
     FROM group_relays gr
     JOIN chat_relays cr ON cr.chat_relay_id = gr.chat_relay_id
   |]
 
-toGroupRelay :: (Int64, GroupMemberId, DBEntityId, ShortLinkContact, Text, Text, Maybe Text, Maybe ImageData, Text, BoolInt) :. (Maybe BoolInt, BoolInt, BoolInt, RelayStatus, Maybe ShortLinkContact) -> GroupRelay
-toGroupRelay ((groupRelayId, groupMemberId, chatRelayId, address, displayName, fullName, shortDescr, image, domains, BI preset) :. (tested, BI enabled, BI deleted, relayStatus, relayLink)) =
+toGroupRelay :: (Int64, GroupMemberId, DBEntityId, ShortLinkContact, Text, Text, Maybe Text, Maybe ImageData, Text, BoolInt) :. (Maybe BoolInt, BoolInt, BoolInt, RelayStatus, Maybe ShortLinkContact, Maybe Text) -> GroupRelay
+toGroupRelay ((groupRelayId, groupMemberId, chatRelayId, address, displayName, fullName, shortDescr, image, domains, BI preset) :. (tested, BI enabled, BI deleted, relayStatus, relayLink, baseWebUrl)) =
   let userChatRelay = UserChatRelay {chatRelayId, address, relayProfile = toRelayProfile (displayName, fullName, shortDescr, image), domains = T.splitOn "," domains, preset, tested = unBI <$> tested, enabled, deleted}
-   in GroupRelay {groupRelayId, groupMemberId, userChatRelay, relayStatus, relayLink}
+      relayCap = RelayCapabilities {baseWebUrl}
+   in GroupRelay {groupRelayId, groupMemberId, userChatRelay, relayStatus, relayLink, relayCap}
 
 createRelayForOwner :: DB.Connection -> VersionRangeChat -> TVar ChaChaDRG -> User -> GroupInfo -> UserChatRelay -> ExceptT StoreError IO GroupMember
 createRelayForOwner db vr gVar user@User {userId, userContactId} GroupInfo {groupId, membership} UserChatRelay {relayProfile = RelayProfile {displayName}} = do
@@ -1491,6 +1495,18 @@ setRelayLinkConfId db m confId relayLink = do
     |]
     (relayLink, currentTs, groupMemberId' m)
 
+updateRelayCapabilities :: DB.Connection -> GroupMember -> RelayCapabilities -> IO ()
+updateRelayCapabilities db m RelayCapabilities {baseWebUrl} = do
+  currentTs <- getCurrentTime
+  DB.execute
+    db
+    [sql|
+      UPDATE group_relays
+      SET base_web_url = ?, updated_at = ?
+      WHERE group_member_id = ?
+    |]
+    (baseWebUrl, currentTs, groupMemberId' m)
+
 getRelayConfId :: DB.Connection -> GroupMember -> ExceptT StoreError IO ConfirmationId
 getRelayConfId db m =
   ExceptT . firstRow fromOnly (SEGroupRelayNotFoundByMemberId $ groupMemberId' m) $
@@ -2327,6 +2343,7 @@ updateGroupProfile db user@User {userId} g@GroupInfo {groupId, localDisplayName,
           UPDATE group_profiles
           SET display_name = ?, full_name = ?, short_descr = ?, description = ?, image = ?,
               group_type = ?, group_link = ?,
+              group_web_page = ?, group_domain = ?, domain_web_page = ?, allow_embedding = ?,
               preferences = ?, member_admission = ?, updated_at = ?
           WHERE group_profile_id IN (
             SELECT group_profile_id
@@ -2334,7 +2351,7 @@ updateGroupProfile db user@User {userId} g@GroupInfo {groupId, localDisplayName,
             WHERE user_id = ? AND group_id = ?
           )
         |]
-        ((newName, fullName, shortDescr, description, image, groupType_, groupLink_) :. (groupPreferences, memberAdmission, currentTs, userId, groupId))
+        ((newName, fullName, shortDescr, description, image, groupType_, groupLink_) :. publicGroupAccessRow publicGroup :. (groupPreferences, memberAdmission, currentTs, userId, groupId))
     updateGroup_ ldn currentTs = do
       DB.execute
         db
@@ -2374,14 +2391,16 @@ updateGroupProfileFromMember db user g@GroupInfo {groupId} Profile {displayName
             [sql|
             SELECT gp.display_name, gp.full_name, gp.short_descr, gp.description, gp.image,
                    gp.group_type, gp.group_link, gp.public_group_id,
+                   gp.group_web_page, gp.group_domain, gp.domain_web_page, gp.allow_embedding,
                    gp.preferences, gp.member_admission
             FROM group_profiles gp
             JOIN groups g ON gp.group_profile_id = g.group_profile_id
             WHERE g.group_id = ?
           |]
             (Only groupId)
-    toGroupProfile (displayName, fullName, shortDescr, description, image, groupType_, groupLink_, publicGroupId_, groupPreferences, memberAdmission) =
-      GroupProfile {displayName, fullName, shortDescr, description, image, publicGroup = toPublicGroupProfile groupType_ groupLink_ publicGroupId_, groupPreferences, memberAdmission}
+    toGroupProfile ((displayName, fullName, shortDescr, description, image, groupType_, groupLink_, publicGroupId_) :. accessRow :. (groupPreferences, memberAdmission)) =
+      let publicGroupAccess = toPublicGroupAccess accessRow
+       in GroupProfile {displayName, fullName, shortDescr, description, image, publicGroup = toPublicGroupProfile groupType_ groupLink_ publicGroupId_ publicGroupAccess, groupPreferences, memberAdmission}
 
 getGroupInfoByUserContactLinkConnReq :: DB.Connection -> VersionRangeChat -> User -> (ConnReqContact, ConnReqContact) -> IO (Maybe GroupInfo)
 getGroupInfoByUserContactLinkConnReq db vr user@User {userId} (cReqSchema1, cReqSchema2) = do

src/Simplex/Chat/Store/Postgres/Migrations.hs

@@ -31,6 +31,7 @@ import Simplex.Chat.Store.Postgres.Migrations.M20260403_item_viewed
 import Simplex.Chat.Store.Postgres.Migrations.M20260429_relay_request_retries
 import Simplex.Chat.Store.Postgres.Migrations.M20260507_relay_inactive_at
 import Simplex.Chat.Store.Postgres.Migrations.M20260514_relay_request_group_link_index
+import Simplex.Chat.Store.Postgres.Migrations.M20260515_public_group_access
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))
 
 schemaMigrations :: [(String, Text, Maybe Text)]
@@ -61,7 +62,8 @@ schemaMigrations =
     ("20260403_item_viewed", m20260403_item_viewed, Just down_m20260403_item_viewed),
     ("20260429_relay_request_retries", m20260429_relay_request_retries, Just down_m20260429_relay_request_retries),
     ("20260507_relay_inactive_at", m20260507_relay_inactive_at, Just down_m20260507_relay_inactive_at),
-    ("20260514_relay_request_group_link_index", m20260514_relay_request_group_link_index, Just down_m20260514_relay_request_group_link_index)
+    ("20260514_relay_request_group_link_index", m20260514_relay_request_group_link_index, Just down_m20260514_relay_request_group_link_index),
+    ("20260515_public_group_access", m20260515_public_group_access, Just down_m20260515_public_group_access)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Chat/Store/Postgres/Migrations/M20260515_public_group_access.hs

@@ -0,0 +1,29 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Chat.Store.Postgres.Migrations.M20260515_public_group_access where
+
+import Data.Text (Text)
+import Text.RawString.QQ (r)
+
+m20260515_public_group_access :: Text
+m20260515_public_group_access =
+  [r|
+ALTER TABLE group_profiles ADD COLUMN group_web_page TEXT;
+ALTER TABLE group_profiles ADD COLUMN group_domain TEXT;
+ALTER TABLE group_profiles ADD COLUMN domain_web_page BIGINT;
+ALTER TABLE group_profiles ADD COLUMN allow_embedding BIGINT;
+
+ALTER TABLE group_relays ADD COLUMN base_web_url TEXT;
+|]
+
+down_m20260515_public_group_access :: Text
+down_m20260515_public_group_access =
+  [r|
+ALTER TABLE group_relays DROP COLUMN base_web_url;
+
+ALTER TABLE group_profiles DROP COLUMN allow_embedding;
+ALTER TABLE group_profiles DROP COLUMN domain_web_page;
+ALTER TABLE group_profiles DROP COLUMN group_domain;
+ALTER TABLE group_profiles DROP COLUMN group_web_page;
+|]

src/Simplex/Chat/Store/Postgres/Migrations/chat_schema.sql

@@ -849,7 +849,11 @@ CREATE TABLE test_chat_schema.group_profiles (
     short_descr text,
     group_type text,
     group_link bytea,
-    public_group_id bytea
+    public_group_id bytea,
+    group_web_page text,
+    group_domain text,
+    domain_web_page bigint,
+    allow_embedding bigint
 );
 
 
@@ -874,7 +878,8 @@ CREATE TABLE test_chat_schema.group_relays (
     relay_link bytea,
     conf_id bytea,
     created_at text DEFAULT now() NOT NULL,
-    updated_at text DEFAULT now() NOT NULL
+    updated_at text DEFAULT now() NOT NULL,
+    base_web_url text
 );
 
 
@@ -962,7 +967,7 @@ CREATE TABLE test_chat_schema.groups (
     public_member_count bigint,
     relay_request_retries bigint DEFAULT 0 NOT NULL,
     relay_request_delay bigint DEFAULT 0 NOT NULL,
-    relay_request_execute_at timestamp with time zone DEFAULT '1970-01-01 04:00:00+04'::timestamp with time zone NOT NULL,
+    relay_request_execute_at timestamp with time zone DEFAULT '1970-01-01 01:00:00+01'::timestamp with time zone NOT NULL,
     relay_inactive_at timestamp with time zone
 );
 

src/Simplex/Chat/Store/SQLite/Migrations.hs

@@ -154,6 +154,7 @@ import Simplex.Chat.Store.SQLite.Migrations.M20260403_item_viewed
 import Simplex.Chat.Store.SQLite.Migrations.M20260429_relay_request_retries
 import Simplex.Chat.Store.SQLite.Migrations.M20260507_relay_inactive_at
 import Simplex.Chat.Store.SQLite.Migrations.M20260514_relay_request_group_link_index
+import Simplex.Chat.Store.SQLite.Migrations.M20260515_public_group_access
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))
 
 schemaMigrations :: [(String, Query, Maybe Query)]
@@ -307,7 +308,8 @@ schemaMigrations =
     ("20260403_item_viewed", m20260403_item_viewed, Just down_m20260403_item_viewed),
     ("20260429_relay_request_retries", m20260429_relay_request_retries, Just down_m20260429_relay_request_retries),
     ("20260507_relay_inactive_at", m20260507_relay_inactive_at, Just down_m20260507_relay_inactive_at),
-    ("20260514_relay_request_group_link_index", m20260514_relay_request_group_link_index, Just down_m20260514_relay_request_group_link_index)
+    ("20260514_relay_request_group_link_index", m20260514_relay_request_group_link_index, Just down_m20260514_relay_request_group_link_index),
+    ("20260515_public_group_access", m20260515_public_group_access, Just down_m20260515_public_group_access)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Chat/Store/SQLite/Migrations/M20260515_public_group_access.hs

@@ -0,0 +1,28 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Chat.Store.SQLite.Migrations.M20260515_public_group_access where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+m20260515_public_group_access :: Query
+m20260515_public_group_access =
+  [sql|
+ALTER TABLE group_profiles ADD COLUMN group_web_page TEXT;
+ALTER TABLE group_profiles ADD COLUMN group_domain TEXT;
+ALTER TABLE group_profiles ADD COLUMN domain_web_page INTEGER;
+ALTER TABLE group_profiles ADD COLUMN allow_embedding INTEGER;
+
+ALTER TABLE group_relays ADD COLUMN base_web_url TEXT;
+|]
+
+down_m20260515_public_group_access :: Query
+down_m20260515_public_group_access =
+  [sql|
+ALTER TABLE group_relays DROP COLUMN base_web_url;
+
+ALTER TABLE group_profiles DROP COLUMN allow_embedding;
+ALTER TABLE group_profiles DROP COLUMN domain_web_page;
+ALTER TABLE group_profiles DROP COLUMN group_domain;
+ALTER TABLE group_profiles DROP COLUMN group_web_page;
+|]

src/Simplex/Chat/Store/SQLite/Migrations/chat_query_plans.txt

@@ -143,6 +143,7 @@ Query:
                 SELECT
                   -- GroupInfo
                   g.group_id, g.local_display_name, gp.display_name, gp.full_name, gp.short_descr, g.local_alias, gp.description, gp.image, gp.group_type, gp.group_link, gp.public_group_id,
+                  gp.group_web_page, gp.group_domain, gp.domain_web_page, gp.allow_embedding,
                   g.enable_ntfs, g.send_rcpts, g.favorite, gp.preferences, gp.member_admission,
                   g.created_at, g.updated_at, g.chat_ts, g.user_member_profile_sent_at,
                   g.conn_full_link_to_connect, g.conn_short_link_to_connect, g.conn_link_prepared_connection, g.conn_link_started_connection, g.welcome_shared_msg_id, g.request_shared_msg_id,
@@ -979,6 +980,7 @@ SEARCH delivery_tasks USING COVERING INDEX idx_delivery_tasks_next (group_id=? A
 Query: 
             SELECT gp.display_name, gp.full_name, gp.short_descr, gp.description, gp.image,
                    gp.group_type, gp.group_link, gp.public_group_id,
+                   gp.group_web_page, gp.group_domain, gp.domain_web_page, gp.allow_embedding,
                    gp.preferences, gp.member_admission
             FROM group_profiles gp
             JOIN groups g ON gp.group_profile_id = g.group_profile_id
@@ -1228,8 +1230,9 @@ Query:
           INSERT INTO group_profiles
             (display_name, full_name, short_descr, description, image,
              group_type, group_link, public_group_id,
+             group_web_page, group_domain, domain_web_page, allow_embedding,
              user_id, preferences, member_admission, created_at, updated_at)
-          VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?)
+          VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)
         
 Plan:
 
@@ -1752,6 +1755,7 @@ Query:
           UPDATE group_profiles
           SET display_name = ?, full_name = ?, short_descr = ?, description = ?, image = ?,
               group_type = ?, group_link = ?,
+              group_web_page = ?, group_domain = ?, domain_web_page = ?, allow_embedding = ?,
               preferences = ?, member_admission = ?, updated_at = ?
           WHERE group_profile_id IN (
             SELECT group_profile_id
@@ -5119,6 +5123,14 @@ SEARCH group_profiles USING INTEGER PRIMARY KEY (rowid=?)
 LIST SUBQUERY 1
 SEARCH groups USING INTEGER PRIMARY KEY (rowid=?)
 
+Query: 
+      UPDATE group_relays
+      SET base_web_url = ?, updated_at = ?
+      WHERE group_member_id = ?
+    
+Plan:
+SEARCH group_relays USING INDEX idx_group_relays_group_member_id (group_member_id=?)
+
 Query: 
       UPDATE group_relays
       SET conf_id = ?, relay_link = ?, updated_at = ?
@@ -5295,6 +5307,7 @@ Query:
     SELECT
       -- GroupInfo
       g.group_id, g.local_display_name, gp.display_name, gp.full_name, gp.short_descr, g.local_alias, gp.description, gp.image, gp.group_type, gp.group_link, gp.public_group_id,
+      gp.group_web_page, gp.group_domain, gp.domain_web_page, gp.allow_embedding,
       g.enable_ntfs, g.send_rcpts, g.favorite, gp.preferences, gp.member_admission,
       g.created_at, g.updated_at, g.chat_ts, g.user_member_profile_sent_at,
       g.conn_full_link_to_connect, g.conn_short_link_to_connect, g.conn_link_prepared_connection, g.conn_link_started_connection, g.welcome_shared_msg_id, g.request_shared_msg_id,
@@ -5331,6 +5344,7 @@ Query:
     SELECT
       -- GroupInfo
       g.group_id, g.local_display_name, gp.display_name, gp.full_name, gp.short_descr, g.local_alias, gp.description, gp.image, gp.group_type, gp.group_link, gp.public_group_id,
+      gp.group_web_page, gp.group_domain, gp.domain_web_page, gp.allow_embedding,
       g.enable_ntfs, g.send_rcpts, g.favorite, gp.preferences, gp.member_admission,
       g.created_at, g.updated_at, g.chat_ts, g.user_member_profile_sent_at,
       g.conn_full_link_to_connect, g.conn_short_link_to_connect, g.conn_link_prepared_connection, g.conn_link_started_connection, g.welcome_shared_msg_id, g.request_shared_msg_id,
@@ -5360,6 +5374,7 @@ Query:
     SELECT
       -- GroupInfo
       g.group_id, g.local_display_name, gp.display_name, gp.full_name, gp.short_descr, g.local_alias, gp.description, gp.image, gp.group_type, gp.group_link, gp.public_group_id,
+      gp.group_web_page, gp.group_domain, gp.domain_web_page, gp.allow_embedding,
       g.enable_ntfs, g.send_rcpts, g.favorite, gp.preferences, gp.member_admission,
       g.created_at, g.updated_at, g.chat_ts, g.user_member_profile_sent_at,
       g.conn_full_link_to_connect, g.conn_short_link_to_connect, g.conn_link_prepared_connection, g.conn_link_started_connection, g.welcome_shared_msg_id, g.request_shared_msg_id,
@@ -5690,7 +5705,7 @@ SEARCH f USING INDEX idx_files_chat_item_id (chat_item_id=?)
 Query: 
     SELECT gr.group_relay_id, gr.group_member_id,
            cr.chat_relay_id, cr.address, cr.display_name, cr.full_name, cr.short_descr, cr.image, cr.domains, cr.preset, cr.tested, cr.enabled, cr.deleted,
-           gr.relay_status, gr.relay_link
+           gr.relay_status, gr.relay_link, gr.base_web_url
     FROM group_relays gr
     JOIN chat_relays cr ON cr.chat_relay_id = gr.chat_relay_id
    
@@ -5707,7 +5722,7 @@ SEARCH m USING INTEGER PRIMARY KEY (rowid=?)
 Query: 
     SELECT gr.group_relay_id, gr.group_member_id,
            cr.chat_relay_id, cr.address, cr.display_name, cr.full_name, cr.short_descr, cr.image, cr.domains, cr.preset, cr.tested, cr.enabled, cr.deleted,
-           gr.relay_status, gr.relay_link
+           gr.relay_status, gr.relay_link, gr.base_web_url
     FROM group_relays gr
     JOIN chat_relays cr ON cr.chat_relay_id = gr.chat_relay_id
    WHERE gr.group_id = ?
@@ -5718,7 +5733,7 @@ SEARCH cr USING INTEGER PRIMARY KEY (rowid=?)
 Query: 
     SELECT gr.group_relay_id, gr.group_member_id,
            cr.chat_relay_id, cr.address, cr.display_name, cr.full_name, cr.short_descr, cr.image, cr.domains, cr.preset, cr.tested, cr.enabled, cr.deleted,
-           gr.relay_status, gr.relay_link
+           gr.relay_status, gr.relay_link, gr.base_web_url
     FROM group_relays gr
     JOIN chat_relays cr ON cr.chat_relay_id = gr.chat_relay_id
    WHERE gr.group_member_id = ?
@@ -5729,7 +5744,7 @@ SEARCH cr USING INTEGER PRIMARY KEY (rowid=?)
 Query: 
     SELECT gr.group_relay_id, gr.group_member_id,
            cr.chat_relay_id, cr.address, cr.display_name, cr.full_name, cr.short_descr, cr.image, cr.domains, cr.preset, cr.tested, cr.enabled, cr.deleted,
-           gr.relay_status, gr.relay_link
+           gr.relay_status, gr.relay_link, gr.base_web_url
     FROM group_relays gr
     JOIN chat_relays cr ON cr.chat_relay_id = gr.chat_relay_id
    WHERE gr.group_relay_id = ?

src/Simplex/Chat/Store/SQLite/Migrations/chat_schema.sql

@@ -125,7 +125,11 @@ CREATE TABLE group_profiles(
   short_descr TEXT,
   group_type TEXT,
   group_link BLOB,
-  public_group_id BLOB
+  public_group_id BLOB,
+  group_web_page TEXT,
+  group_domain TEXT,
+  domain_web_page INTEGER,
+  allow_embedding INTEGER
 ) STRICT;
 CREATE TABLE groups(
   group_id INTEGER PRIMARY KEY, -- local group ID
@@ -778,6 +782,8 @@ CREATE TABLE group_relays(
   conf_id BLOB,
   created_at TEXT NOT NULL DEFAULT(datetime('now')),
   updated_at TEXT NOT NULL DEFAULT(datetime('now'))
+  ,
+  base_web_url TEXT
 ) STRICT;
 CREATE INDEX contact_profiles_index ON contact_profiles(
   display_name,

src/Simplex/Chat/Store/Shared.hs

@@ -665,18 +665,20 @@ type BusinessChatInfoRow = (Maybe BusinessChatType, Maybe MemberId, Maybe Member
 
 type GroupKeysRow = (Maybe C.PrivateKeyEd25519, Maybe C.PublicKeyEd25519, Maybe C.PrivateKeyEd25519)
 
-type GroupInfoRow = (Int64, GroupName, GroupName, Text, Maybe Text, Text, Maybe Text, Maybe ImageData, Maybe GroupType, Maybe ShortLinkContact, Maybe B64UrlByteString) :. (Maybe MsgFilter, Maybe BoolInt, BoolInt, Maybe GroupPreferences, Maybe GroupMemberAdmission) :. (UTCTime, UTCTime, Maybe UTCTime, Maybe UTCTime) :. PreparedGroupRow :. BusinessChatInfoRow :. (BoolInt, Maybe RelayStatus, Maybe UIThemeEntityOverrides, Int64, Maybe Int64, Maybe CustomData, Maybe Int64, Int, Maybe ConnReqContact) :. GroupKeysRow :. GroupMemberRow
+type GroupInfoRow = (Int64, GroupName, GroupName, Text, Maybe Text, Text, Maybe Text, Maybe ImageData, Maybe GroupType, Maybe ShortLinkContact, Maybe B64UrlByteString) :. PublicGroupAccessRow :. (Maybe MsgFilter, Maybe BoolInt, BoolInt, Maybe GroupPreferences, Maybe GroupMemberAdmission) :. (UTCTime, UTCTime, Maybe UTCTime, Maybe UTCTime) :. PreparedGroupRow :. BusinessChatInfoRow :. (BoolInt, Maybe RelayStatus, Maybe UIThemeEntityOverrides, Int64, Maybe Int64, Maybe CustomData, Maybe Int64, Int, Maybe ConnReqContact) :. GroupKeysRow :. GroupMemberRow
+
+type PublicGroupAccessRow = (Maybe Text, Maybe Text, Maybe BoolInt, Maybe BoolInt)
 
 type GroupMemberRow = (GroupMemberId, GroupId, Int64, MemberId, VersionChat, VersionChat, GroupMemberRole, GroupMemberCategory, GroupMemberStatus, BoolInt, Maybe MemberRestrictionStatus) :. (Maybe Int64, Maybe GroupMemberId, ContactName, Maybe ContactId, ProfileId) :. ProfileRow :. (UTCTime, UTCTime) :. (Maybe UTCTime, Int64, Int64, Int64, Maybe UTCTime, Maybe C.PublicKeyEd25519, Maybe ShortLinkContact)
 
 type ProfileRow = (ProfileId, ContactName, Text, Maybe Text, Maybe ImageData, Maybe ConnLinkContact, Maybe ChatPeerType, LocalAlias, Maybe Preferences)
 
 toGroupInfo :: VersionRangeChat -> Int64 -> [ChatTagId] -> GroupInfoRow -> GroupInfo
-toGroupInfo vr userContactId chatTags ((groupId, localDisplayName, displayName, fullName, shortDescr, localAlias, description, image, groupType_, groupLink_, publicGroupId_) :. (enableNtfs_, sendRcpts, BI favorite, groupPreferences, memberAdmission) :. (createdAt, updatedAt, chatTs, userMemberProfileSentAt) :. preparedGroupRow :. businessRow :. (BI useRelays, relayOwnStatus, uiThemes, currentMembers, publicMemberCount, customData, chatItemTTL, membersRequireAttention, viaGroupLinkUri) :. groupKeysRow :. userMemberRow) =
+toGroupInfo vr userContactId chatTags ((groupId, localDisplayName, displayName, fullName, shortDescr, localAlias, description, image, groupType_, groupLink_, publicGroupId_) :. accessRow :. (enableNtfs_, sendRcpts, BI favorite, groupPreferences, memberAdmission) :. (createdAt, updatedAt, chatTs, userMemberProfileSentAt) :. preparedGroupRow :. businessRow :. (BI useRelays, relayOwnStatus, uiThemes, currentMembers, publicMemberCount, customData, chatItemTTL, membersRequireAttention, viaGroupLinkUri) :. groupKeysRow :. userMemberRow) =
   let membership = (toGroupMember userContactId userMemberRow) {memberChatVRange = vr}
       chatSettings = ChatSettings {enableNtfs = fromMaybe MFAll enableNtfs_, sendRcpts = unBI <$> sendRcpts, favorite}
       fullGroupPreferences = mergeGroupPreferences groupPreferences
-      publicGroup = toPublicGroupProfile groupType_ groupLink_ publicGroupId_
+      publicGroup = toPublicGroupProfile groupType_ groupLink_ publicGroupId_ (toPublicGroupAccess accessRow)
       groupKeys = toGroupKeys publicGroupId_ groupKeysRow
       groupProfile = GroupProfile {displayName, fullName, shortDescr, description, image, publicGroup, groupPreferences, memberAdmission}
       businessChat = toBusinessChatInfo businessRow
@@ -690,10 +692,25 @@ toPreparedGroup = \case
     Just PreparedGroup {connLinkToConnect = CCLink fullLink shortLink_, connLinkPreparedConnection, connLinkStartedConnection, welcomeSharedMsgId, requestSharedMsgId}
   _ -> Nothing
 
-toPublicGroupProfile :: Maybe GroupType -> Maybe ShortLinkContact -> Maybe B64UrlByteString -> Maybe PublicGroupProfile
-toPublicGroupProfile (Just groupType) (Just groupLink) (Just publicGroupId) =
-  Just PublicGroupProfile {groupType, groupLink, publicGroupId}
-toPublicGroupProfile _ _ _ = Nothing
+toPublicGroupProfile :: Maybe GroupType -> Maybe ShortLinkContact -> Maybe B64UrlByteString -> Maybe PublicGroupAccess -> Maybe PublicGroupProfile
+toPublicGroupProfile (Just groupType) (Just groupLink) (Just publicGroupId) publicGroupAccess =
+  Just PublicGroupProfile {groupType, groupLink, publicGroupId, publicGroupAccess}
+toPublicGroupProfile _ _ _ _ = Nothing
+
+publicGroupAccessRow :: Maybe PublicGroupProfile -> PublicGroupAccessRow
+publicGroupAccessRow pgp = case pgp >>= publicGroupAccess of
+  Just PublicGroupAccess {groupWebPage, groupDomain, domainWebPage, allowEmbedding} ->
+    (groupWebPage, groupDomain, Just (BI domainWebPage), Just (BI allowEmbedding))
+  Nothing -> (Nothing, Nothing, Nothing, Nothing)
+
+toPublicGroupAccess :: PublicGroupAccessRow -> Maybe PublicGroupAccess
+toPublicGroupAccess (groupWebPage, groupDomain, domainWebPage_, allowEmbedding_)
+  | isJust groupWebPage || isJust groupDomain || domainWebPage || allowEmbedding =
+      Just PublicGroupAccess {groupWebPage, groupDomain, domainWebPage, allowEmbedding}
+  | otherwise = Nothing
+  where
+    domainWebPage = maybe False unBI domainWebPage_
+    allowEmbedding = maybe False unBI allowEmbedding_
 
 toGroupKeys :: Maybe B64UrlByteString -> GroupKeysRow -> Maybe GroupKeys
 toGroupKeys (Just publicGroupId) (rootPrivKey_, rootPubKey_, Just memberPrivKey) =
@@ -760,6 +777,7 @@ groupInfoQueryFields =
     SELECT
       -- GroupInfo
       g.group_id, g.local_display_name, gp.display_name, gp.full_name, gp.short_descr, g.local_alias, gp.description, gp.image, gp.group_type, gp.group_link, gp.public_group_id,
+      gp.group_web_page, gp.group_domain, gp.domain_web_page, gp.allow_embedding,
       g.enable_ntfs, g.send_rcpts, g.favorite, gp.preferences, gp.member_admission,
       g.created_at, g.updated_at, g.chat_ts, g.user_member_profile_sent_at,
       g.conn_full_link_to_connect, g.conn_short_link_to_connect, g.conn_link_prepared_connection, g.conn_link_started_connection, g.welcome_shared_msg_id, g.request_shared_msg_id,

src/Simplex/Chat/Types.hs

@@ -793,10 +793,19 @@ instance FromField GroupType where fromField = fromTextField_ textDecode
 
 instance ToField GroupType where toField = toField . textEncode
 
+data PublicGroupAccess = PublicGroupAccess
+  { groupWebPage :: Maybe Text,
+    groupDomain :: Maybe Text,
+    domainWebPage :: Bool,
+    allowEmbedding :: Bool
+  }
+  deriving (Eq, Show)
+
 data PublicGroupProfile = PublicGroupProfile
   { groupType :: GroupType,
     groupLink :: ShortLinkContact,
-    publicGroupId :: B64UrlByteString -- group identity = sha256(genesis root key), immutable
+    publicGroupId :: B64UrlByteString, -- group identity = sha256(genesis root key), immutable
+    publicGroupAccess :: Maybe PublicGroupAccess
   }
   deriving (Eq, Show)
 
@@ -2084,6 +2093,8 @@ instance ToJSON GroupType where
   toJSON = textToJSON
   toEncoding = textToEncoding
 
+$(JQ.deriveJSON defaultJSON ''PublicGroupAccess)
+
 $(JQ.deriveJSON defaultJSON ''PublicGroupProfile)
 
 $(JQ.deriveJSON defaultJSON ''GroupProfile)

tests/ChatTests/Groups.hs

@@ -3251,6 +3251,12 @@ testGLinkReviewMember =
       alice ##> "/_delete member chat #1 5"
       alice <## "bad chat command: member is pending"
 
+      -- moderator can't accept member with a role higher than their own
+      dan ##> "/_accept member #1 5 admin"
+      dan <## "#team: you have insufficient permissions for this action, the required role is admin"
+      dan ##> "/_accept member #1 5 owner"
+      dan <## "#team: you have insufficient permissions for this action, the required role is owner"
+
       -- accept member
       dan ##> "/_accept member #1 5 member"
       concurrentlyN_