Evgeny @ SimpleX Chat
1.2 KiB
Simplex.Messaging.Parsers
Attoparsec helpers and Aeson JSON encoding options.
Source: Parsers.hs
sumTypeJSON (platform-dependent JSON encoding)
On Darwin with the swiftJSON CPP flag, sumTypeJSON uses ObjectWithSingleField encoding with tag "_owsf". On all other platforms, it uses TaggedObject encoding with "type" / "data" keys.
This means the same Haskell type produces different JSON on macOS/iOS vs Linux. Cross-platform JSON interchange must use taggedObjectJSON or singleFieldJSON directly, not sumTypeJSON.
The _owsf tag enables Swift clients to convert between the two encodings — it's a marker that the value was encoded as ObjectWithSingleField rather than TaggedObject.
parseE vs parseE'
parseE requires full input consumption (endOfInput). parseE' does not — it succeeds if the parser matches a prefix. Using parseE' where parseE is needed silently ignores trailing input.
base64P
Parses standard base64 (+ and /), not base64url (- and _). Contrast with base64urlP in Simplex.Messaging.Encoding.String which parses URL-safe base64.