feat(template): derive ErrorTemplate from proto Template option

.gitattributes

@@ -0,0 +1,3 @@
+* text=auto eol=lf
+internal/testdata/gen/** linguist-generated=true
+*.pb.go linguist-generated=true

.github/workflows/ci.yml

@@ -12,12 +12,30 @@ permissions:
   pull-requests: read
 
 jobs:
+  generated-code-up-to-date:
+    name: Generated Code Up-To-Date
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5.0.0
+      - uses: bufbuild/buf-setup-action@v1.50.0
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Regenerate Go bindings
+        run: buf generate
+      - name: Verify clean working tree
+        run: |
+          if ! git diff --quiet --exit-code; then
+            echo "Generated code is out of date. Run 'buf generate' and commit the result."
+            git diff
+            exit 1
+          fi
+
   quality-assurance:
     name: Quality Assurance
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go-version: [1.24.x]
+        go-version: [1.26.x]
 
     steps:
       - uses: actions/checkout@v5.0.0

buf.gen.yaml

@@ -0,0 +1,16 @@
+version: v2
+managed:
+  enabled: true
+  override:
+    - file_option: go_package_prefix
+      value: github.com/TrogonStack/trogonerror/internal/testdata/gen
+    - file_option: go_package_prefix
+      module: buf.build/trogonstack/trogon-proto
+      value: github.com/TrogonStack/trogonproto/gen
+plugins:
+  - remote: buf.build/protocolbuffers/go:v1.36.5
+    out: internal/testdata/gen
+    opt:
+      - paths=source_relative
+inputs:
+  - directory: internal/testdata/proto

error.go

@@ -795,6 +795,8 @@ type ErrorTemplate struct {
 	message    string // empty string means use code's default message
 	visibility Visibility
 	help       *Help
+	metadata   Metadata
+	fields     []protoFieldSpec
 }
 
 // TemplateOption represents options that can be applied to ErrorTemplate
@@ -866,6 +868,9 @@ func (et *ErrorTemplate) NewError(options ...ErrorOption) *TrogonError {
 	if et.help != nil {
 		baseOptions = append(baseOptions, WithHelp(*et.help))
 	}
+	for key, value := range et.metadata {
+		baseOptions = append(baseOptions, WithMetadataValue(value.visibility, key, value.value))
+	}
 
 	return NewError(et.domain, et.reason, append(baseOptions, options...)...)
 }

example_test.go

@@ -5,8 +5,33 @@ import (
 	"time"
 
 	"github.com/TrogonStack/trogonerror"
+	testdatav1 "github.com/TrogonStack/trogonerror/internal/testdata/gen/trogonerror/testdata/v1"
 )
 
+var userNotFoundTpl = trogonerror.NewErrorTemplateFromProto[*testdatav1.UserNotFound]()
+
+func ExampleNewErrorTemplateFromProto() {
+	err := userNotFoundTpl.FromProto(&testdatav1.UserNotFound{
+		UserId: "gid://shopify/Customer/1234567890",
+	})
+
+	fmt.Println(err.Error())
+	// Output:
+	// User does not exist.
+	//   visibility: PUBLIC
+	//   domain: shopify.users
+	//   reason: USER_NOT_FOUND
+	//   code: NOT_FOUND
+	//   metadata:
+	//     - component: users visibility=PUBLIC
+	//     - region: us-east-1 visibility=PUBLIC
+	//     - team: platform-identity visibility=INTERNAL
+	//     - tenantId: default-tenant visibility=PUBLIC
+	//     - userId: gid://shopify/Customer/1234567890 visibility=PUBLIC
+	//
+	// - User Docs: https://docs.shopify.com/users
+}
+
 func ExampleNewError() {
 	err := trogonerror.NewError("shopify.users", "NOT_FOUND",
 		trogonerror.WithCode(trogonerror.CodeNotFound),

go.mod

@@ -1,10 +1,15 @@
 module github.com/TrogonStack/trogonerror
 
-go 1.24.2
+go 1.26
 
-require github.com/stretchr/testify v1.11.1
+require (
+	github.com/TrogonStack/trogonproto v0.1.0
+	github.com/stretchr/testify v1.11.1
+	google.golang.org/protobuf v1.36.11
+)
 
 require (
+	buf.build/gen/go/elixir-protobuf/protobuf/protocolbuffers/go v1.36.11-20260114033128-d590dff383e9.1 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -1,9 +1,17 @@
+buf.build/gen/go/elixir-protobuf/protobuf/protocolbuffers/go v1.36.11-20260114033128-d590dff383e9.1 h1:YyaDi4kIyhOWTWYN0OzoKC+Wo+DpSC5aQxfe69fVUWA=
+buf.build/gen/go/elixir-protobuf/protobuf/protocolbuffers/go v1.36.11-20260114033128-d590dff383e9.1/go.mod h1:fQtoq8UKgFiCFI3I7uyYxA2iVU1CplNN0PJpdFLdXHI=
+github.com/TrogonStack/trogonproto v0.1.0 h1:l3Skhw6rY4zskjS2d8GfXK9fKB6n5lIKObksAjknpUg=
+github.com/TrogonStack/trogonproto v0.1.0/go.mod h1:RfEvGMmPYqH8RLE1I63nJZ3OmLUbBa4XSjya06aPLVE=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
+github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
+google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

internal/testdata/proto/buf.lock

@@ -0,0 +1,12 @@
+# Generated by buf. DO NOT EDIT.
+version: v2
+deps:
+  - name: buf.build/elixir-protobuf/protobuf
+    commit: d590dff383e94f28bacec0e8015c4daa
+    digest: b5:fa4a17975e0ed6b54e3e7637d659a6358fb18ebd8a931462003cea62d43336fb02c8685076e4cb5129875b13f13c2c6dfe7205f2215d7666efdfc5cce836a2de
+  - name: buf.build/protocolbuffers/wellknowntypes
+    commit: 4e1ccfa6827947beb55974645a315b8d
+    digest: b5:eb5228b1abd02064d6ff0248918500c1ec1ce7df69126af3f220c0b67d81ff45bdf9f016a8e66cd9c1e534f18afc6d8e090d400604c5331d551a68d05f7e7be9
+  - name: buf.build/trogonstack/trogon-proto
+    commit: e7442b2c978348c9864565ec086db7a5
+    digest: b5:2dba0ce198c5981e5d870610f5a5eaadf499d28bffb9d34fd4df5decc35ac5cbcedb670eeaf431312ab59e6d4050f7eb5559a5715e3db06322033658269468ef

internal/testdata/proto/buf.yaml

@@ -0,0 +1,6 @@
+version: v2
+modules:
+  - path: .
+deps:
+  - buf.build/trogonstack/trogon-proto
+  - buf.build/elixir-protobuf/protobuf

internal/testdata/proto/trogonerror/testdata/v1/errors.proto

@@ -0,0 +1,34 @@
+syntax = "proto3";
+
+package trogonerror.testdata.v1;
+
+import "trogon/error/v1alpha1/code.proto";
+import "trogon/error/v1alpha1/options.proto";
+import "trogon/error/v1alpha1/visibility.proto";
+
+message UserNotFound {
+  option (trogon.error.v1alpha1.message).template = {
+    domain: "shopify.users",
+    reason: "USER_NOT_FOUND",
+    message: "User does not exist.",
+    code: NOT_FOUND,
+    visibility: VISIBILITY_PUBLIC,
+    help_links: [{url: "https://docs.shopify.com/users", description: "User Docs"}],
+    metadata: [
+      {key: "component", value: "users", visibility: VISIBILITY_PUBLIC},
+      {key: "team", value: "platform-identity", visibility: VISIBILITY_INTERNAL}
+    ]
+  };
+
+  string user_id = 1 [(trogon.error.v1alpha1.field) = {
+    visibility: VISIBILITY_PUBLIC
+  }];
+  string tenant_id = 2 [(trogon.error.v1alpha1.field) = {
+    visibility: VISIBILITY_PUBLIC,
+    default_value: "default-tenant"
+  }];
+  string region = 3 [(trogon.error.v1alpha1.field) = {
+    visibility: VISIBILITY_PUBLIC,
+    value: "us-east-1"
+  }];
+}