build(aio): add checkContentRules processor (#22759)

This processor will enable us to write rules about
how the content should appear, such as:

* no headings in markdown content
* only one sentence per line
* no single character parameter names
* etc.

PR Close #22759

aio/tools/transforms/angular-base-package/index.js

@@ -30,6 +30,7 @@ module.exports = new Package('angular-base', [
   .processor(require('./processors/fixInternalDocumentLinks'))
   .processor(require('./processors/copyContentAssets'))
   .processor(require('./processors/renderLinkInfo'))
+  .processor(require('./processors/checkContentRules'))
 
   // overrides base packageInfo and returns the one for the 'angular/angular' repo.
   .factory('packageInfo', function() { return require(path.resolve(PROJECT_ROOT, 'package.json')); })

aio/tools/transforms/angular-base-package/processors/checkContentRules.js

@@ -0,0 +1,69 @@
+
+/**
+ * A processor that can run arbitrary checking rules against properties of documents
+
+ * The configuration for the processor is via the `docTypeRules`.
+ * This is a hash of docTypes to rulesets.
+ * Each rules set is a hash of properties to rule functions.
+ *
+ * The processor will run each rule function against each matching property of each matching doc.
+ *
+ * An example rule might look like:
+ *
+ * ```
+ * function noMarkdownHeadings(doc, prop, value) {
+ *   const match = /^\s?#+\s+.*$/m.exec(value);
+ *   if (match) {
+ *     return `Headings not allowed in "${prop}" property. Found "${match[0]}"`;
+ *   }
+ * }
+ * ```
+ *
+ */
+module.exports = function checkContentRules(log, createDocMessage) {
+  return {
+    /**
+     * {
+     *   [docType]: {
+     *     [property]: Array<(doc: Document, property: string, value: any) => string|undefined>
+     *   }
+     * }
+     */
+    docTypeRules: {},
+    failOnContentErrors: false,
+    $runAfter: ['tags-extracted'],
+    $runBefore: ['processing-docs'],
+    $process(docs) {
+      const errors = [];
+      docs.forEach(doc => {
+        const docErrors = [];
+        const rules = this.docTypeRules[doc.docType] || {};
+        if (rules) {
+          Object.keys(rules).forEach(property => {
+            const ruleFns = rules[property];
+            ruleFns.forEach(ruleFn => {
+              const error = ruleFn(doc, property, doc[property]);
+              if (error) {
+                docErrors.push(error);
+              }
+            });
+          });
+        }
+        if (docErrors.length) {
+          errors.push({ doc, errors: docErrors });
+        }
+      });
+
+      if (errors.length) {
+        log.error('Content contains errors');
+        errors.forEach(docError => {
+          const errors = docError.errors.join('\n        ');
+          log.error(createDocMessage(errors + '\n        ', docError.doc));
+        });
+        if (this.failOnContentErrors) {
+          throw new Error('Stopping due to content errors.');
+        }
+      }
+    }
+  };
+};

aio/tools/transforms/angular-base-package/processors/checkContentRules.spec.js

@@ -0,0 +1,108 @@
+var testPackage = require('../../helpers/test-package');
+var Dgeni = require('dgeni');
+
+describe('checkContentRules processor', function() {
+  let processor, logger;
+
+  beforeEach(function() {
+    const dgeni = new Dgeni([testPackage('angular-base-package')]);
+    const injector = dgeni.configureInjector();
+    processor = injector.get('checkContentRules');
+    logger = injector.get('log');
+  });
+
+  it('should exist on the injector', () => {
+    expect(processor).toBeDefined();
+    expect(processor.$process).toEqual(jasmine.any(Function));
+  });
+
+  it('shpuld run at the right time', () => {
+    expect(processor.$runAfter).toEqual(['tags-extracted']);
+    expect(processor.$runBefore).toEqual(['processing-docs']);
+  });
+
+  it('should do nothing if not configured', () => {
+    const docs = [{ docType: 'test', description: '## heading 2' }];
+    processor.$process(docs);
+    expect(docs).toEqual([{ docType: 'test', description: '## heading 2' }]);
+
+    expect(logger.error).not.toHaveBeenCalled();
+  });
+
+  it('should run configured rules against matching docs', () => {
+    const nameSpy1 = jasmine.createSpy('name 1');
+    const nameSpy2 = jasmine.createSpy('name 2');
+    const nameSpy3 = jasmine.createSpy('name 3');
+    const descriptionSpy1 = jasmine.createSpy('description 1');
+    const descriptionSpy2 = jasmine.createSpy('description 2');
+    const descriptionSpy3 = jasmine.createSpy('description 3');
+
+    processor.docTypeRules = {
+      'test1': {
+        name: [nameSpy1, nameSpy3],
+        description: [descriptionSpy1, descriptionSpy3]
+      },
+      'test2': {
+        name: [nameSpy2],
+        description: [descriptionSpy2]
+      }
+    };
+
+    const docs = [
+      { docType: 'test1', description: 'test doc 1', name: 'test-1' },
+      { docType: 'test2', description: 'test doc 2', name: 'test-2' }
+    ];
+    processor.$process(docs);
+    expect(nameSpy1).toHaveBeenCalledTimes(1);
+    expect(nameSpy1).toHaveBeenCalledWith(docs[0], 'name', 'test-1');
+    expect(nameSpy2).toHaveBeenCalledTimes(1);
+    expect(nameSpy2).toHaveBeenCalledWith(docs[1], 'name', 'test-2');
+    expect(nameSpy3).toHaveBeenCalledTimes(1);
+    expect(nameSpy3).toHaveBeenCalledWith(docs[0], 'name', 'test-1');
+    expect(descriptionSpy1).toHaveBeenCalledTimes(1);
+    expect(descriptionSpy1).toHaveBeenCalledWith(docs[0], 'description', 'test doc 1');
+    expect(descriptionSpy2).toHaveBeenCalledTimes(1);
+    expect(descriptionSpy2).toHaveBeenCalledWith(docs[1], 'description', 'test doc 2');
+    expect(descriptionSpy3).toHaveBeenCalledTimes(1);
+    expect(descriptionSpy3).toHaveBeenCalledWith(docs[0], 'description', 'test doc 1');
+  });
+
+  it('should log errors if the rule returns error messages', () => {
+    const nameSpy1 = jasmine.createSpy('name 1').and.returnValue('name error message');
+    const descriptionSpy1 = jasmine.createSpy('description 1').and.returnValue('description error message');
+
+    processor.docTypeRules = {
+      'test1': {
+        name: [nameSpy1],
+        description: [descriptionSpy1]
+      }
+    };
+
+    const docs = [
+      { docType: 'test1', description: 'test doc 1', name: 'test-1' },
+      { docType: 'test2', description: 'test doc 2', name: 'test-2' }
+    ];
+
+    processor.$process(docs);
+
+    expect(logger.error).toHaveBeenCalledTimes(2);
+    expect(logger.error).toHaveBeenCalledWith('Content contains errors');
+    expect(logger.error).toHaveBeenCalledWith(`name error message
+        description error message
+         - doc "test-1" (test1) `);
+  });
+
+  it('should throw an error if `failOnContentErrors` is true and errors are found', () => {
+    const errorRule = jasmine.createSpy('error rule').and.returnValue('some error');
+    processor.docTypeRules = {
+      'test': { description: [errorRule] }
+    };
+    processor.failOnContentErrors = true;
+
+    const docs = [
+      { docType: 'test', description: 'test doc' },
+    ];
+    expect(() => processor.$process(docs)).toThrowError('Stopping due to content errors.');
+  });
+
+});