Replace REST with JSON-RPC

[emmiegit]

Since we've finalized use of DEEPWELL as an internal API only, external-facing requirements no longer apply. We've already removed things like per-IP ratelimiting and now we've been facing a limitation of REST APIs, which is our desire to send more rich error data than one of a handful of relevant HTTP status codes. As such, we're shifting to a JSON-RPC-based internal API for DEEPWELL, which gets rid of the unnecessary HTTP complexities we don't need, and instead essentially has a remote method invocation system, with serde_json-backed serialization for input/output. tide (the web server) has been entirely removed, and so a lot of the lines changed are from log line diffs.

Likewise, I have taken the existing services::Error object and made it have a larger number of more specific error cases, since we are now sending those over the wire instead of bunching them into much more vague HTTP statuses.

I have also been able to use the transaction closure, which is wrapped outside of each method. Thus, boilerplate related to setting up the transaction and ensuring it is committed is now removed. For most methods, this means the wrapper code is very simple. Take the message_draft_send method:

pub async fn message_draft_send(
    ctx: &ServiceContext<'_>,
    params: Params<'static>,
) -> Result<MessageRecordModel> {
    let SendMessageDraft { message_draft_id } = params.parse()?;
    info!("Sending message draft with ID {message_draft_id}");
    MessageService::send(ctx, &message_draft_id).await
}

For local testing of DEEPWELL (for instance, using curl), the endpoint is now POST http://localhost:2747/jsonrpc. This always returns HTTP 200, error information is passed in the JSON result, in accordance with the JSON-RPC standard. I have modified the necessary code in framerail as well, and refactored it a bit. There, we are now using the json-rpc-2.0 library to act as a JSON-RPC client.

[codecov]

Codecov Report

Merging #1644 (3f34e9c) into develop (6ccb1ce) will decrease coverage by 39.28%.
The diff coverage is 2.19%.

@@             Coverage Diff             @@
##           develop   #1644       +/-   ##
===========================================
- Coverage    41.02%   1.75%   -39.28%     
===========================================
  Files          342     129      -213     
  Lines        10537    5128     -5409     
===========================================
- Hits          4323      90     -4233     
+ Misses        6214    5038     -1176     

Flag	Coverage Δ
deepwell	1.75% <2.19%> (+0.02%)	⬆️
ftml	?

Files	Coverage Δ
deepwell/src/config/file.rs	10.76% <ø> (ø)
deepwell/src/models/alias.rs	0.00% <ø> (ø)
deepwell/src/models/file.rs	0.00% <ø> (ø)
deepwell/src/models/file_revision.rs	0.00% <ø> (ø)
deepwell/src/models/filter.rs	0.00% <ø> (ø)
deepwell/src/models/message.rs	0.00% <ø> (ø)
deepwell/src/models/message_recipient.rs	0.00% <ø> (ø)
deepwell/src/models/message_record.rs	0.00% <ø> (ø)
deepwell/src/models/message_report.rs	0.00% <ø> (ø)
deepwell/src/models/page.rs	0.00% <ø> (ø)
... and 88 more

... and 209 files with indirect coverage changes

[emmiegit]

thanks @Yossipossi1