feat: add ability to set custom comment content

__tests__/comment-upserter.test.ts

@@ -3,7 +3,7 @@ import {RestEndpointMethodTypes} from '@octokit/plugin-rest-endpoint-methods'
 import {RestEndpointMethods} from '@octokit/plugin-rest-endpoint-methods/dist-types/generated/method-types.d'
 import {EqualMatchingInjectorConfig, It, Mock, Times} from 'moq.ts'
 
-import {CommentUpserterImpl, HEADER} from '../src/comment-upserter'
+import {CommentUpserterImpl, DEFAULT_COMMENT_PREAMBLE, HEADER} from '../src/comment-upserter'
 import {Repo} from '../src/github-types'
 
 describe('CommentUpserterImpl', () => {
@@ -35,13 +35,6 @@ describe('CommentUpserterImpl', () => {
       }
     ]
 
-    const commentBody =
-      HEADER +
-      [
-        '| db/migrate/\\*\\* | @cto, @dba |',
-        '| .github/\\*\\*<br>spec/\\*.rb | @ci |'
-      ].join('\n')
-
     const stubListComments = (comments: string[]): void => {
       const listResponse = {
         data: comments.map((comment, index) => ({id: index + 1, body: comment}))
@@ -74,6 +67,16 @@ describe('CommentUpserterImpl', () => {
       })
 
       it('creates a comment', async () => {
+        const expectedCommentBody =
+          HEADER +
+          [
+            DEFAULT_COMMENT_PREAMBLE,
+            '| File Patterns | Mentions |',
+            '| - | - |',
+            '| db/migrate/\\*\\* | @cto, @dba |',
+            '| .github/\\*\\*<br>spec/\\*.rb | @ci |'
+          ].join('\n')
+
         issuesMock
           .setup(instance => instance.createComment(It.IsAny()))
           .returnsAsync(
@@ -88,7 +91,42 @@ describe('CommentUpserterImpl', () => {
           instance.createComment({
             ...repo,
             issue_number: pullNumber,
-            body: commentBody
+            body: expectedCommentBody
+          })
+        )
+      })
+
+      it('creates a comment with custom comment content', async () => {
+        const customContent = {
+          preamble: 'Added you as a subscriber.',
+          epilogue: '> [CodeMention](https://github.com/tobyhs/codemention)'
+        }
+        const expectedCommentBody =
+          HEADER +
+          [
+            customContent.preamble,
+            '| File Patterns | Mentions |',
+            '| - | - |',
+            '| db/migrate/\\*\\* | @cto, @dba |',
+            '| .github/\\*\\*<br>spec/\\*.rb | @ci |',
+            `\n${customContent.epilogue}`
+          ].join('\n')
+
+        issuesMock
+          .setup(instance => instance.createComment(It.IsAny()))
+          .returnsAsync(
+            new Mock<
+              RestEndpointMethodTypes['issues']['createComment']['response']
+            >().object()
+          )
+
+        await upserter.upsert(repo, pullNumber, rules, customContent)
+
+        issuesMock.verify(instance =>
+          instance.createComment({
+            ...repo,
+            issue_number: pullNumber,
+            body: expectedCommentBody
           })
         )
       })
@@ -97,6 +135,16 @@ describe('CommentUpserterImpl', () => {
     describe('when a codemention comment exists', () => {
       describe('and the comment is different', () => {
         it('updates the comment', async () => {
+          const expectedCommentBody =
+          HEADER +
+          [
+            DEFAULT_COMMENT_PREAMBLE,
+            '| File Patterns | Mentions |',
+            '| - | - |',
+            '| db/migrate/\\*\\* | @cto, @dba |',
+            '| .github/\\*\\*<br>spec/\\*.rb | @ci |'
+          ].join('\n')
+
           const existingComment = HEADER + '| config/brakeman.yml | @security |'
           stubListComments(['First', existingComment])
 
@@ -114,14 +162,24 @@ describe('CommentUpserterImpl', () => {
             instance.updateComment({
               ...repo,
               comment_id: 2,
-              body: commentBody
+              body: expectedCommentBody
             })
           )
         })
       })
 
       describe('and the comment is the same', () => {
         it('does not update the comment', async () => {
+          const commentBody =
+          HEADER +
+          [
+            DEFAULT_COMMENT_PREAMBLE,
+            '| File Patterns | Mentions |',
+            '| - | - |',
+            '| db/migrate/\\*\\* | @cto, @dba |',
+            '| .github/\\*\\*<br>spec/\\*.rb | @ci |'
+          ].join('\n')
+
           stubListComments(['First', commentBody])
           await upserter.upsert(repo, pullNumber, rules)
 

__tests__/fixtures/codemention.yml

@@ -1,3 +1,6 @@
+commentConfiguration:
+  preamble: 'testing preamble'
+  epilogue: 'testing epilogue'
 rules:
   - patterns: ['config/**']
     mentions: ['sysadmin']

__tests__/runner.test.ts

@@ -97,7 +97,7 @@ describe('Runner', () => {
         }
       ]
       commentUpserterMock.verify(instance =>
-        instance.upsert(repo, prNumber, matchingRules)
+        instance.upsert(repo, prNumber, matchingRules, {preamble: 'testing preamble', epilogue: 'testing epilogue'})
       )
     })
   })

src/comment-upserter.ts

@@ -2,15 +2,13 @@ import * as core from '@actions/core'
 import {RestEndpointMethods} from '@octokit/plugin-rest-endpoint-methods/dist-types/generated/method-types.d'
 import markdownEscape from 'markdown-escape'
 
-import {MentionRule} from './configuration'
+import {CommentConfiguration, MentionRule} from './configuration'
 import {Repo} from './github-types'
 
-export const HEADER = [
-  '<!-- codemention header -->',
-  '[CodeMention](https://github.com/tobyhs/codemention):\n',
-  '| File Patterns | Mentions |',
-  '| - | - |\n'
-].join('\n')
+export const HEADER = '<!-- codemention header -->'
+
+export const DEFAULT_COMMENT_PREAMBLE =
+  '[CodeMention](https://github.com/tobyhs/codemention):'
 
 /**
  * @see {@link upsert}
@@ -22,8 +20,14 @@ export interface CommentUpserter {
    * @param repo - repository that the pull request is in
    * @param pullNumber - number that identifies the pull request
    * @param rules - mention rules to use in the comment
+   * @param commentContent - comment content to print above matching rules table
    */
-  upsert(repo: Repo, pullNumber: number, rules: MentionRule[]): Promise<void>
+  upsert(
+    repo: Repo,
+    pullNumber: number,
+    rules: MentionRule[],
+    commentConfiguration?: CommentConfiguration
+  ): Promise<void>
 }
 
 export class CommentUpserterImpl implements CommentUpserter {
@@ -36,7 +40,8 @@ export class CommentUpserterImpl implements CommentUpserter {
   async upsert(
     repo: Repo,
     pullNumber: number,
-    rules: MentionRule[]
+    rules: MentionRule[],
+    commentConfiguration?: CommentConfiguration
   ): Promise<void> {
     const issuesApi = this.octokitRest.issues
     const listResponse = await issuesApi.listComments({
@@ -47,7 +52,7 @@ export class CommentUpserterImpl implements CommentUpserter {
     const existingComment = listResponse.data.find(
       c => c.body !== undefined && c.body.startsWith(HEADER)
     )
-    const commentBody = this.createCommentBody(rules)
+    const commentBody = this.createCommentBody(rules, commentConfiguration)
 
     if (existingComment === undefined) {
       if (rules.length > 0) {
@@ -76,18 +81,31 @@ export class CommentUpserterImpl implements CommentUpserter {
 
   /**
    * @param rules - mention rules to use in the comment
+   * @param commentContent - comment content to print above matching rules table
    * @returns text to be used in a GitHub pull request comment body
    */
-  private createCommentBody(rules: MentionRule[]): string {
-    const body = rules
-      .map(rule => {
-        const patterns = rule.patterns
-          .map(pattern => markdownEscape(pattern, ['slashes']))
-          .join('<br>')
-        const mentions = rule.mentions.map(name => `@${name}`).join(', ')
-        return `| ${patterns} | ${mentions} |`
-      })
+  private createCommentBody(
+    rules: MentionRule[],
+    commentConfiguration?: CommentConfiguration
+  ): string {
+    const mentionsTableRows = rules.map(rule => {
+      const patterns = rule.patterns
+        .map(pattern => markdownEscape(pattern, ['slashes']))
+        .join('<br>')
+      const mentions = rule.mentions.map(name => `@${name}`).join(', ')
+      return `| ${patterns} | ${mentions} |`
+    })
+    const content = [
+      commentConfiguration?.preamble ?? DEFAULT_COMMENT_PREAMBLE,
+      '| File Patterns | Mentions |',
+      '| - | - |',
+      ...mentionsTableRows,
+      commentConfiguration?.epilogue
+        ? `\n${commentConfiguration.epilogue}` // need two line breaks to finish table before epilogue
+        : undefined
+    ]
+      .filter(elem => elem !== undefined)
       .join('\n')
-    return `${HEADER}${body}`
+    return `${HEADER}${content}`
   }
 }

src/configuration.ts

@@ -9,10 +9,22 @@ export interface MentionRule {
   mentions: string[]
 }
 
+/**
+ * A set of configuration items for the comment posted by the bot
+ */
+export interface CommentConfiguration {
+  /** Comment content to print above matching rules table */
+  preamble?: string
+  /** Comment content to print below matching rules table */
+  epilogue?: string
+}
+
 /**
  * Configuration for the GitHub Action
  */
 export interface Configuration {
   /** Rules for mentioning */
   rules: MentionRule[]
+  /** Configuration for comment */
+  commentConfiguration?: CommentConfiguration
 }

src/runner.ts

@@ -36,17 +36,18 @@ export default class Runner {
       return
     }
 
-    const configuration = await this.configurationReader.read(
-      repo,
-      pullRequest.base.sha
-    )
-    const filesChanged = await this.filesChangedReader.read(
-      repo,
-      pullRequest.number
-    )
+    const [configuration, filesChanged] = await Promise.all([
+      this.configurationReader.read(repo, pullRequest.base.sha),
+      this.filesChangedReader.read(repo, pullRequest.number)
+    ])
     const matchingRules = configuration.rules.filter(
       rule => micromatch(filesChanged, rule.patterns).length > 0
     )
-    await this.commentUpserter.upsert(repo, pullRequest.number, matchingRules)
+    await this.commentUpserter.upsert(
+      repo,
+      pullRequest.number,
+      matchingRules,
+      configuration.commentConfiguration
+    )
   }
 }