gitbay/Networking/Envelope.swift

 1import Foundation
 2
 3/// Exit codes shared by the CLI, SSH and both HTTP surfaces.
 4/// `internal/protocol/protocol.go` is the source of truth.
 5nonisolated enum ExitCode: Int, Sendable {
 6    case ok = 0
 7    case failure = 1
 8    case usage = 2
 9    case notFound = 3
10    case denied = 4
11    case protocolError = 5
12}
13
14/// Every response from either API surface is the command's own JSON
15/// envelope with `exit_code` added.
16///
17/// `data` is absent when a command emits an empty result — Go omits a nil
18/// slice — so an empty list arrives as no key at all rather than `[]`.
19/// `output` carries commands that write raw text instead of JSON (`mr
20/// diff`, `help`); the server wraps those.
21nonisolated struct Envelope<Payload: Decodable & Sendable>: Decodable, Sendable {
22    let protocolVersion: Int
23    let data: Payload?
24    let error: String?
25    let stderr: String?
26    let output: String?
27    let exitCode: Int?
28
29    enum CodingKeys: String, CodingKey {
30        case protocolVersion = "protocol_version"
31        case data, error, stderr, output
32        case exitCode = "exit_code"
33    }
34
35    /// The message to put in front of a person. `error` and `stderr` were
36    /// both written to be read by one.
37    var message: String? {
38        let text = error ?? stderr
39        guard let text, !text.isEmpty else { return nil }
40        return text
41    }
42}
43
44/// Placeholder for commands whose `data` we do not decode. It accepts any
45/// JSON, so discarding a payload never fails on its shape.
46nonisolated struct NoPayload: Decodable, Sendable {
47    init(from _: any Decoder) throws {}
48}