feat: Add cred-class-name-suffix lint rule (no-changelog) (#29801)

packages/@n8n/eslint-plugin-community-nodes/README.md

@@ -48,6 +48,7 @@ export default [
 | :--------------------------------------------------------------------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------ | :--- | :--- | :- | :- | :- |
 | [ai-node-package-json](docs/rules/ai-node-package-json.md)                               | Enforce consistency between n8n.aiNodeSdkVersion and ai-node-sdk peer dependency in community node packages                                 | ✅ ☑️ |      |    |    |    |
 | [cred-class-field-icon-missing](docs/rules/cred-class-field-icon-missing.md)             | Credential class must have an `icon` property defined                                                                                       | ✅ ☑️ |      |    | 💡 |    |
+| [cred-class-name-suffix](docs/rules/cred-class-name-suffix.md)                           | Credential class names must be suffixed with `Api`                                                                                          | ✅ ☑️ |      | 🔧 |    |    |
 | [cred-class-oauth2-naming](docs/rules/cred-class-oauth2-naming.md)                       | OAuth2 credentials must include `OAuth2` in the class name, `name`, and `displayName`                                                       | ✅ ☑️ |      | 🔧 |    |    |
 | [credential-documentation-url](docs/rules/credential-documentation-url.md)               | Enforce valid credential documentationUrl format (URL or lowercase alphanumeric slug)                                                       | ✅ ☑️ |      | 🔧 |    |    |
 | [credential-password-field](docs/rules/credential-password-field.md)                     | Ensure credential fields with sensitive names have typeOptions.password = true                                                              | ✅ ☑️ |      | 🔧 |    |    |

packages/@n8n/eslint-plugin-community-nodes/docs/rules/cred-class-name-suffix.md

@@ -0,0 +1,46 @@
+# Credential class names must be suffixed with `Api` (`@n8n/community-nodes/cred-class-name-suffix`)
+
+💼 This rule is enabled in the following configs: ✅ `recommended`, ☑️ `recommendedWithoutN8nCloudSupport`.
+
+🔧 This rule is automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).
+
+<!-- end auto-generated rule header -->
+
+## Rule Details
+
+Credential classes (those implementing `ICredentialType` in `*.credentials.ts` files) must have a class name ending in `Api`. This is the n8n convention so credentials are easily recognisable in code, in import statements, and across the credential registry.
+
+For OAuth2 credentials extending the OAuth2 base, see the sibling rule `cred-class-oauth2-naming` which enforces the more specific `OAuth2Api` suffix.
+
+## Opt-out
+
+For legitimate exceptions (for example credentials representing custom auth headers where the `Api` suffix would be misleading), disable the rule for the specific class with a standard ESLint comment:
+
+```typescript
+// eslint-disable-next-line @n8n/community-nodes/cred-class-name-suffix
+export class CustomAuthHeader implements ICredentialType {
+  // ...
+}
+```
+
+## Examples
+
+### ❌ Incorrect
+
+```typescript
+export class MyService implements ICredentialType {
+  name = 'myServiceApi';
+  displayName = 'My Service API';
+  properties: INodeProperties[] = [];
+}
+```
+
+### ✅ Correct
+
+```typescript
+export class MyServiceApi implements ICredentialType {
+  name = 'myServiceApi';
+  displayName = 'My Service API';
+  properties: INodeProperties[] = [];
+}
+```

packages/@n8n/eslint-plugin-community-nodes/src/plugin.ts

@@ -40,6 +40,7 @@ const configs = {
 			'@n8n/community-nodes/resource-operation-pattern': 'warn',
 			'@n8n/community-nodes/credential-documentation-url': 'error',
 			'@n8n/community-nodes/cred-class-field-icon-missing': 'error',
+			'@n8n/community-nodes/cred-class-name-suffix': 'error',
 			'@n8n/community-nodes/cred-class-oauth2-naming': 'error',
 			'@n8n/community-nodes/node-connection-type-literal': 'error',
 			'@n8n/community-nodes/missing-paired-item': 'error',
@@ -77,6 +78,7 @@ const configs = {
 			'@n8n/community-nodes/credential-documentation-url': 'error',
 			'@n8n/community-nodes/resource-operation-pattern': 'warn',
 			'@n8n/community-nodes/cred-class-field-icon-missing': 'error',
+			'@n8n/community-nodes/cred-class-name-suffix': 'error',
 			'@n8n/community-nodes/cred-class-oauth2-naming': 'error',
 			'@n8n/community-nodes/node-connection-type-literal': 'error',
 			'@n8n/community-nodes/missing-paired-item': 'error',

packages/@n8n/eslint-plugin-community-nodes/src/rules/cred-class-name-suffix.test.ts

@@ -0,0 +1,74 @@
+import { RuleTester } from '@typescript-eslint/rule-tester';
+
+import { CredClassNameSuffixRule } from './cred-class-name-suffix.js';
+
+const ruleTester = new RuleTester();
+
+const credFilePath = '/tmp/TestCredential.credentials.ts';
+const nonCredFilePath = '/tmp/SomeHelper.ts';
+
+function createCredentialCode(className: string): string {
+	return `
+import type { ICredentialType, INodeProperties } from 'n8n-workflow';
+
+export class ${className} implements ICredentialType {
+	name = 'testApi';
+	displayName = 'Test API';
+	properties: INodeProperties[] = [];
+}`;
+}
+
+function createRegularClass(className: string): string {
+	return `
+export class ${className} {
+	name = 'test';
+}`;
+}
+
+ruleTester.run('cred-class-name-suffix', CredClassNameSuffixRule, {
+	valid: [
+		{
+			name: 'credential class with Api suffix',
+			filename: credFilePath,
+			code: createCredentialCode('TestApi'),
+		},
+		{
+			name: 'credential class with OAuth2Api suffix',
+			filename: credFilePath,
+			code: createCredentialCode('TestOAuth2Api'),
+		},
+		{
+			name: 'class not implementing ICredentialType is ignored',
+			filename: credFilePath,
+			code: createRegularClass('SomeHelper'),
+		},
+		{
+			name: 'non-.credentials.ts file is ignored',
+			filename: nonCredFilePath,
+			code: createCredentialCode('TestCredential'),
+		},
+	],
+	invalid: [
+		{
+			name: 'credential class missing Api suffix',
+			filename: credFilePath,
+			code: createCredentialCode('TestCredential'),
+			errors: [{ messageId: 'missingSuffix', data: { name: 'TestCredential' } }],
+			output: createCredentialCode('TestCredentialApi'),
+		},
+		{
+			name: 'credential class name ending in Ap',
+			filename: credFilePath,
+			code: createCredentialCode('TestAp'),
+			errors: [{ messageId: 'missingSuffix', data: { name: 'TestAp' } }],
+			output: createCredentialCode('TestApi'),
+		},
+		{
+			name: 'credential class name ending in A',
+			filename: credFilePath,
+			code: createCredentialCode('TestA'),
+			errors: [{ messageId: 'missingSuffix', data: { name: 'TestA' } }],
+			output: createCredentialCode('TestApi'),
+		},
+	],
+});

packages/@n8n/eslint-plugin-community-nodes/src/rules/cred-class-name-suffix.ts

@@ -0,0 +1,57 @@
+import { isCredentialTypeClass, isFileType, createRule } from '../utils/index.js';
+
+function addApiSuffix(name: string): string {
+	if (name.endsWith('Ap')) return `${name}i`;
+	if (name.endsWith('A')) return `${name}pi`;
+	return `${name}Api`;
+}
+
+export const CredClassNameSuffixRule = createRule({
+	name: 'cred-class-name-suffix',
+	meta: {
+		type: 'problem',
+		docs: {
+			description: 'Credential class names must be suffixed with `Api`',
+		},
+		messages: {
+			missingSuffix: "Credential class name '{{name}}' must end with 'Api'",
+		},
+		fixable: 'code',
+		schema: [],
+	},
+	defaultOptions: [],
+	create(context) {
+		if (!isFileType(context.filename, '.credentials.ts')) {
+			return {};
+		}
+
+		return {
+			ClassDeclaration(node) {
+				if (!isCredentialTypeClass(node)) {
+					return;
+				}
+
+				const classNameNode = node.id;
+				if (!classNameNode) {
+					return;
+				}
+
+				const className = classNameNode.name;
+				if (className.endsWith('Api')) {
+					return;
+				}
+
+				const fixedName = addApiSuffix(className);
+
+				context.report({
+					node: classNameNode,
+					messageId: 'missingSuffix',
+					data: { name: className },
+					fix(fixer) {
+						return fixer.replaceText(classNameNode, fixedName);
+					},
+				});
+			},
+		};
+	},
+});

packages/@n8n/eslint-plugin-community-nodes/src/rules/index.ts

@@ -2,6 +2,7 @@ import type { AnyRuleModule } from '@typescript-eslint/utils/ts-eslint';
 
 import { AiNodePackageJsonRule } from './ai-node-package-json.js';
 import { CredClassFieldIconMissingRule } from './cred-class-field-icon-missing.js';
+import { CredClassNameSuffixRule } from './cred-class-name-suffix.js';
 import { CredClassOAuth2NamingRule } from './cred-class-oauth2-naming.js';
 import { CredentialDocumentationUrlRule } from './credential-documentation-url.js';
 import { CredentialPasswordFieldRule } from './credential-password-field.js';
@@ -54,6 +55,7 @@ export const rules = {
 	'credential-documentation-url': CredentialDocumentationUrlRule,
 	'node-class-description-icon-missing': NodeClassDescriptionIconMissingRule,
 	'cred-class-field-icon-missing': CredClassFieldIconMissingRule,
+	'cred-class-name-suffix': CredClassNameSuffixRule,
 	'cred-class-oauth2-naming': CredClassOAuth2NamingRule,
 	'node-connection-type-literal': NodeConnectionTypeLiteralRule,
 	'node-operation-error-itemindex': NodeOperationErrorItemIndexRule,