feat: add protoc-gen-connect-go-service-struct plugin

[yordis]

No description provided.

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📥 Commits

Reviewing files that changed from the base of the PR and between 3a6b8d1 and 30b6c46.

⛔ Files ignored due to path filters (1)

• go.sum is excluded by !**/*.sum

📒 Files selected for processing (5)

• .gitignore (1 hunks)
• cmd/protoc-gen-connect-go-servicestruct/README.md (1 hunks)
• cmd/protoc-gen-connect-go-servicestruct/main.go (1 hunks)
• cmd/protoc-gen-connect-go-servicestruct/main_test.go (1 hunks)
• go.mod (1 hunks)

Walkthrough

Introduces a new protoc plugin (protoc-gen-connect-go-servicestruct) that generates Go service structs and handler function types for Connect RPC services, adds its README, comprehensive tests, adjusts module dependencies, and updates .gitignore to ignore the plugin’s generated build artifact.

Changes

Cohort / File(s)	Summary
Git ignore config ./.gitignore	Added ignore entry for generated build file: protoc-gen-connect-go-servicestruct, with header comment.
Plugin documentation cmd/protoc-gen-connect-go-servicestruct/README.md	New README describing plugin purpose, installation, usage with protoc/buf, generation behavior, and example wiring.
Protoc plugin implementation cmd/protoc-gen-connect-go-servicestruct/main.go	New generator: groups files by Go import path; emits “.servicestruct.connect.go”; generates service structs, per-RPC handler func types, server wrapper methods; handles deprecation/comments; supports --version and help.
Plugin tests cmd/protoc-gen-connect-go-servicestruct/main_test.go	New tests covering version output, generation for unary/streaming RPCs, no-service case, and multiple services with same method names; helper subprocess runner.
Module dependencies ./go.mod	Added testify; updated/added indirect deps (go-cmp v0.6.0, x/net, yaml.v3, spew, difflib); reorganized require blocks.

Sequence Diagram(s)

sequenceDiagram
  autonumber
  participant protoc as protoc/buf
  participant plugin as protoc-gen-connect-go-servicestruct
  participant protogen as protogen API
  participant fs as File System

  protoc->>plugin: CodeGeneratorRequest (files, params)
  plugin->>protogen: Parse request, analyze services
  loop per Go import path group
    plugin->>plugin: Generate service structs & handler types
    plugin->>fs: Emit *.servicestruct.connect.go (in-memory response)
  end
  plugin-->>protoc: CodeGeneratorResponse (generated files)

Loading

sequenceDiagram
  autonumber
  participant App as Application Server
  participant S as <ServiceName>Struct
  participant H as <MethodName>Func (handler)
  participant Conn as connect runtime

  App->>S: Register S with Connect mux
  Conn->>S: Invoke RPC (unary/streaming)
  alt Unary
    S->>H: ctx, *connect.Request[In]
    H-->>S: *connect.Response[Out], error
  else Client stream
    S->>H: ctx, *connect.ClientStream[In]
    H-->>S: *connect.Response[Out], error
  else Server stream
    S->>H: ctx, *connect.Request[In], *connect.ServerStream[Out]
    H-->>S: error
  else Bidi stream
    S->>H: ctx, *connect.BidiStream[In,Out]
    H-->>S: error
  end
  S-->>Conn: Forward result/error

Loading

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~60 minutes

Poem

I nibbled on proto and handler vine,
Wove structs and streams in tidy line.
With tests that hop through unary glades,
And bidis where the buffer wades.
Ignore the crumbs, deps neatly stacked—
My paws compiled a service pack! 🐇✨

Pre-merge checks and finishing touches

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description Check	⚠️ Warning	No pull request description was provided by the author, so the PR does not describe any part of the changeset and therefore fails this check. The absence of an author-written description forces reviewers to infer intent solely from the diff.	Ask the author to add a brief description summarizing the plugin's purpose, the main files/dirs added (cmd/protoc-gen-connect-go-servicestruct, README, tests, go.mod), any dependency or compatibility notes, and a short usage example or link to documentation to aid reviewers and release-note authors.
Docstring Coverage	⚠️ Warning	Docstring coverage is 5.56% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (1 passed)

Check name	Status	Explanation
Title Check	✅ Passed	The title succinctly and accurately describes the primary change: adding a protoc plugin to generate Connect service structs. It directly matches the changeset which introduces a new cmd/protoc-gen-connect-go-servicestruct tool (plus README, tests, and go.mod updates). The phrasing is concise and specific enough for repository history and review.

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[coderabbitai]

Actionable comments posted: 1

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

go.mod (1)

3-3: Invalid go directive: use major.minor only

go 1.24.2 is not valid in go.mod. The directive must be go 1.24 (patch versions are not allowed).

Apply this diff:

-go 1.24.2
+go 1.24

If you need to pin a specific toolchain, add a separate toolchain directive:

toolchain go1.24.2

🧹 Nitpick comments (5)

cmd/protoc-gen-connect-go-servicestruct/README.md (1)

1-110: Solid README; add prerequisites section for clarity

Consider a short “Requirements” block listing protoc, protoc-gen-go, and protoc-gen-connect-go with minimum versions, plus the Go version (e.g., Go 1.24+). Helps users avoid setup surprises.

cmd/protoc-gen-connect-go-servicestruct/main_test.go (1)

308-323: Minor: exitCode checks are redundant after require.NoError

require.NoError(cmd.Run()) already guarantees exitCode == 0. You can drop the extra equality assert, or switch to checking exitCode and use assert.NoError on run to keep both signals.

cmd/protoc-gen-connect-go-servicestruct/main.go (3)

55-61: Decouple --version from connect library version

Printing connect.Version reports the Connect library version, not this plugin’s. Expose a plugin version variable and set it via -ldflags during release builds; drop the unused connect import afterward.

Apply this diff to use a pluggable version:

 func main() {
-	if len(os.Args) == 2 && os.Args[1] == "--version" {
-		if _, err := fmt.Fprintln(os.Stdout, connect.Version); err != nil {
+	if len(os.Args) == 2 && os.Args[1] == "--version" {
+		if _, err := fmt.Fprintln(os.Stdout, version); err != nil {
 			os.Exit(1)
 		}
 		os.Exit(0)
 	}

Add this right after the const block:

+// version is set at build time: -ldflags "-X main.version=$(git describe --tags --always --dirty)"
+var version = "dev"

And remove the now‑unused import:

-import (
-	"bytes"
-	"fmt"
-	"os"
-	"strings"
-	"unicode/utf8"
-
-	connect "connectrpc.com/connect"
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"strings"
+	"unicode/utf8"

---

80-92: Stabilize output ordering for deterministic builds

Map iteration over packageGroups is random; consider sorting groups and files to reduce churn in generated diffs and make tests more robust.

Example patch (also add sort to imports):

 import (
   "bytes"
   "fmt"
   "os"
   "strings"
   "unicode/utf8"
+  "sort"
@@
- for _, files := range packageGroups {
-   generatePackage(plugin, files)
- }
+ // stable order of packages
+ pkgKeys := make([]string, 0, len(packageGroups))
+ for k := range packageGroups {
+   pkgKeys = append(pkgKeys, k)
+ }
+ sort.Strings(pkgKeys)
+ for _, k := range pkgKeys {
+   files := packageGroups[k]
+   sort.Slice(files, func(i, j int) bool { return files[i].Desc.Path() < files[j].Desc.Path() })
+   generatePackage(plugin, files)
+ }

---

179-191: Optional: guard nil handlers to improve UX

Calling a nil *Func field will panic at runtime. Consider defaulting to a stub that returns an unimplemented error, or check for nil and return a clear error.

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between c73622a and 3a6b8d1.

⛔ Files ignored due to path filters (1)

• go.sum is excluded by !**/*.sum

📒 Files selected for processing (5)

• .gitignore (1 hunks)
• cmd/protoc-gen-connect-go-servicestruct/README.md (1 hunks)
• cmd/protoc-gen-connect-go-servicestruct/main.go (1 hunks)
• cmd/protoc-gen-connect-go-servicestruct/main_test.go (1 hunks)
• go.mod (1 hunks)

🔇 Additional comments (2)

.gitignore (1)

33-35: Ignore rule for plugin binary looks good

Covers both root and nested outputs when running go build from different working dirs.

cmd/protoc-gen-connect-go-servicestruct/main_test.go (1)

25-37: Nice parallelized test scaffolding

Good use of table-ish subtests and compiler version metadata to mimic protoc. Assertions read cleanly.