feat: Add rule for AIP-162 Commit request name field

docs/rules/0162/commit-request-name-field.md

@@ -0,0 +1,76 @@
+---
+rule:
+  aip: 162
+  name: [core, '0162', commit-request-name-field]
+  summary: Commit RPCs must have a `name` field in the request.
+permalink: /162/commit-request-name-field
+redirect_from:
+  - /0162/commit-request-name-field
+---
+
+# Commit requests: Name field
+
+This rule enforces that all `Commit` methods have a `string name`
+field in the request message, as mandated in [AIP-162][].
+
+## Details
+
+This rule looks at any message matching `Commit*Request` and complains if
+either the `name` field is missing or it has any type other than `string`.
+
+## Examples
+
+**Incorrect** code for this rule:
+
+```proto
+// Incorrect.
+// Should include a `string name` field.
+message CommitBookRequest {
+}
+```
+
+```proto
+// Incorrect.
+message CommitBookRequest {
+  // Field type should be `string`.
+  bytes name = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference).type = "library.googleapis.com/Book"
+  ];
+}
+```
+
+**Correct** code for this rule:
+
+```proto
+// Correct.
+message CommitBookRequest {
+  string name = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference).type = "library.googleapis.com/Book"
+  ];
+}
+```
+
+## Disabling
+
+If you need to violate this rule, use a leading comment above the message (if
+the `name` field is missing) or above the field (if it is the wrong type).
+Remember to also include an [aip.dev/not-precedent][] comment explaining why.
+
+```proto
+message CommitBookRequest {
+  // (-- api-linter: core::0162::commit-request-name-field=disabled
+  //     aip.dev/not-precedent: We need to do this because reasons. --)
+  bytes name = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference).type = "library.googleapis.com/Book"
+  ];
+}
+```
+
+If you need to violate this rule for an entire file, place the comment at the
+top of the file.
+
+[aip-162]: https://aip.dev/162
+[aip.dev/not-precedent]: https://aip.dev/not-precedent

rules/aip0162/aip0162.go

@@ -30,6 +30,7 @@ func AddRules(r lint.RuleRegistry) error {
 		commitHTTPBody,
 		commitHTTPMethod,
 		commitHTTPURISuffix,
+		commitRequestNameField,
 		commitRequestMessageName,
 		tagRevisionHTTPBody,
 		tagRevisionHTTPMethod,
@@ -59,9 +60,15 @@ func isTagRevisionRequestMessage(m *desc.MessageDescriptor) bool {
 }
 
 var commitMethodRegexp = regexp.MustCompile(`^Commit(?:[A-Za-z0-9]+)$`)
+var commitReqMessageRegexp = regexp.MustCompile(`^Commit(?:[A-Za-z0-9]+)Request$`)
 var commitURINameRegexp = regexp.MustCompile(`:commit$`)
 
 // Returns true if this is an AIP-162 Commit method, false otherwise.
 func isCommitMethod(m *desc.MethodDescriptor) bool {
 	return commitMethodRegexp.MatchString(m.GetName())
 }
+
+// Returns true if this is an AIP-162 Commit request message, false otherwise.
+func isCommitRequestMessage(m *desc.MessageDescriptor) bool {
+	return commitReqMessageRegexp.MatchString(m.GetName())
+}

rules/aip0162/commit_request_name_field.go

@@ -0,0 +1,52 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package aip0162
+
+import (
+	"fmt"
+
+	"github.com/googleapis/api-linter/lint"
+	"github.com/googleapis/api-linter/locations"
+	"github.com/jhump/protoreflect/desc"
+	"github.com/jhump/protoreflect/desc/builder"
+)
+
+// The Commit request message should have a name field.
+var commitRequestNameField = &lint.MessageRule{
+	Name:   lint.NewRuleName(162, "commit-request-name-field"),
+	OnlyIf: isCommitRequestMessage,
+	LintMessage: func(m *desc.MessageDescriptor) []lint.Problem {
+		// Rule check: Establish that a `name` field is present.
+		nameField := m.FindFieldByName("name")
+		if nameField == nil {
+			return []lint.Problem{{
+				Message:    fmt.Sprintf("Message %q has no `name` field.", m.GetName()),
+				Descriptor: m,
+			}}
+		}
+
+		// Rule check: Establish that the name field is a string.
+		if nameField.GetType() != builder.FieldTypeString().GetType() || nameField.IsRepeated() {
+			return []lint.Problem{{
+				Message:    "`name` field on Commit request message must be a singular string.",
+				Descriptor: nameField,
+				Location:   locations.FieldType(nameField),
+				Suggestion: "string",
+			}}
+		}
+
+		return nil
+	},
+}

rules/aip0162/commit_request_name_field_test.go

@@ -0,0 +1,51 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package aip0162
+
+import (
+	"testing"
+
+	"github.com/googleapis/api-linter/rules/internal/testutils"
+	"github.com/jhump/protoreflect/desc"
+)
+
+func TestCommitRequestNameField(t *testing.T) {
+	for _, test := range []struct {
+		name     string
+		RPC      string
+		Field    string
+		problems testutils.Problems
+	}{
+		{"Valid", "CommitBook", "string name = 1;", nil},
+		{"Missing", "CommitBook", "", testutils.Problems{{Message: "no `name`"}}},
+		{"InvalidType", "CommitBook", "int32 name = 1;", testutils.Problems{{Suggestion: "string"}}},
+		{"IrrelevantRPCName", "EnumerateBooks", "", nil},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			f := testutils.ParseProto3Tmpl(t, `
+				message {{.RPC}}Request {
+					{{.Field}}
+				}
+			`, test)
+			var d desc.Descriptor = f.GetMessageTypes()[0]
+			if test.name == "InvalidType" {
+				d = f.GetMessageTypes()[0].GetFields()[0]
+			}
+			if diff := test.problems.SetDescriptor(d).Diff(commitRequestNameField.Lint(f)); diff != "" {
+				t.Errorf(diff)
+			}
+		})
+	}
+}