Add configuration file support and exclude option

config.js

@@ -12,7 +12,8 @@ const config = {
   moreInfoTitle: 'For more information about the issues follow the links: \n',
   tslintProjectWebsite: 'https://github.com/webschik/tslint-config-security',
   numFilesPerPage: 30,
-  numAnnotationsPerUpdate: 50
+  numAnnotationsPerUpdate: 50,
+  configFilePath: '.precaution.yaml'
 }
 
 const annotationsLevels = {

filter.js

@@ -0,0 +1,48 @@
+// Copyright 2019 VMware, Inc.
+// SPDX-License-Identifier: BSD-2-Clause
+
+const { config } = require('./config')
+
+const minimatch = require('minimatch')
+const path = require('path')
+
+/**
+ * Checks whether a file should be excluded from processing
+ * @param {String} filePath path of file to check
+ * @param {String[]} excludes array of exclusion rules to compare to
+ */
+function isExcluded (filePath, excludes) {
+  let ok = false
+  for (let excludeRule of excludes) {
+    excludeRule = path.normalize(excludeRule)
+    if (minimatch(filePath, excludeRule, { matchBase: true })) {
+      ok = true
+      break
+    }
+  }
+  return ok
+}
+
+/**
+ * Filters the listed files and returns only the files relevant to us
+ * @param {*} rawData the raw output from list files API call
+ * @param {String[]} excludes array of exclusion rules in glob format provided by the user
+ * @return {Promise[]<any>} the filtered GitHub response
+ */
+function filterData (rawData, excludes) {
+  return rawData.data
+    .filter(file =>
+      config.fileExtensions.reduce(
+        (acc, ext) => acc || file.filename.endsWith(ext),
+        false
+      )
+    )
+    .filter(fileJSON => fileJSON.status !== 'removed')
+    .map(fileInfo => {
+      return fileInfo.filename
+    })
+    .filter(filePath => !isExcluded(filePath, excludes))
+}
+
+module.exports.filterData = filterData
+module.exports.isExcluded = isExcluded

github_api_helper.js

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: BSD-2-Clause
 
 const { config } = require('./config')
+const { filterData } = require('./filter')
 
 const rawMediaType = 'application/vnd.github.v3.raw'
 
@@ -27,24 +28,42 @@ function inProgressAPIresponse (context, headSha) {
 }
 
 /**
- * Filters the listed files and returns only the files relevant to us
- * @param {*} rawData the raw output from list files API call
- * @return {Promise[]<any>} the filtered GitHub response
+ * Get Precaution config file contents as raw data,
+ * if that file exists.
+ * @param {import('probot').Context} context Probot context
+ * @param {String} customConfigPath Optional (default value config.configFilePath)
+ * @return {Promise<any>} GitHub response
+ * See https://developer.github.com/v3/repos/contents/#get-contents
  */
-function filterData (rawData) {
-  return rawData.data.filter(file => config.fileExtensions.reduce((acc, ext) => acc || file.filename.endsWith(ext), false))
-    .filter(fileJSON => fileJSON.status !== 'removed').map(fileInfo => {
-      return fileInfo.filename
+async function getConfigFile (context, customConfigPath = config.configFilePath) {
+  let { owner, repo } = context.repo()
+  // GitHub doesn't provide "checkIfFileExists" API endpoint.
+  // That's why we should try to download the file and if we have
+  // 404 error code the file doesn't exist in the repository.
+  try {
+    return await context.github.repos.getContents({
+      owner,
+      repo,
+      path: customConfigPath,
+      headers: { accept: rawMediaType }
     })
+  } catch (error) {
+    if (error.code === 404) {
+      return null
+    } else {
+      throw new Error(error)
+    }
+  }
 }
 
 /**
  * Get list of files modified by a pull request
  * @param {import('probot').Context} context Probot context
  * @param {number} number the pull request number inside the repository
+ * @param {Object} configObj configuration object populated by a config file
  * @returns {String[]} paths to the diff files from the pull request relevant to us
  */
-async function getPRFiles (context, number) {
+async function getPRFiles (context, number, configObj) {
   const { owner, repo } = context.repo()
 
   // See https://developer.github.com/v3/pulls/#list-pull-requests-files
@@ -54,11 +73,11 @@ async function getPRFiles (context, number) {
     number: number,
     per_page: config.numFilesPerPage
   })
-
-  let data = filterData(response)
+  let excludes = configObj && configObj.exclude ? configObj.exclude : []
+  let data = filterData(response, excludes)
   while (context.github.hasNextPage(response)) {
     response = await context.github.getNextPage(response)
-    data = data.concat(filterData(response))
+    data = data.concat(filterData(response, excludes))
   }
   return Promise.all(data)
 }
@@ -197,3 +216,4 @@ module.exports.getPRFiles = getPRFiles
 module.exports.getContents = getRawFileContents
 module.exports.sendResults = sendResults
 module.exports.getConclusion = getConclusion
+module.exports.getConfigFile = getConfigFile

index.js

@@ -5,6 +5,7 @@ const cache = require('./cache')
 const { config } = require('./config')
 const apiHelper = require('./github_api_helper')
 const { runLinters } = require('./runner')
+const yaml = require('js-yaml')
 
 /**
  * @param {import('probot').Application} app - Probot's Application class.
@@ -56,12 +57,16 @@ async function runLinterFromPRData (pullRequests, context, headSha) {
   const checkRunResponse = apiHelper.inProgressAPIresponse(context, headSha)
 
   try {
+    // For now only deal with one PR
+    const PR = pullRequests[0]
+
+    // Loads the Precaution configuration file
+    const rawObj = await apiHelper.getConfigFile(context)
+    const configObj = rawObj ? yaml.safeLoad(rawObj.data) : null
     // Process all pull requests associated with check suite
-    const PRsDownloadedPromise = pullRequests.map(pr => processPullRequest(pr, context))
+    const PRsDownloadedPromise = pullRequests.map(pr => processPullRequest(pr, context, configObj))
     const resolvedPRs = await Promise.all(PRsDownloadedPromise)
 
-    // For now only deal with one PR
-    const PR = pullRequests[0]
     // Sometimes the resolverPR list contains undefined members
     const inputFiles = resolvedPRs[0].filter((file) => file)
 
@@ -85,15 +90,16 @@ async function runLinterFromPRData (pullRequests, context, headSha) {
 /**
  * Retrieve list of files modified by PR and download them to cache
  * @param {import('probot').Context} context
+ * @param {Object} configObj configuration object populated by a config file
  * @returns {Promise<string[]>} Paths to the downloaded PR files
  */
-async function processPullRequest (pullRequest, context) {
+async function processPullRequest (pullRequest, context, configObj) {
   const number = pullRequest.number
   const ref = pullRequest.head.ref
   const id = pullRequest.id
   const repoID = context.payload.repository.id
 
-  const response = await apiHelper.getPRFiles(context, number)
+  const response = await apiHelper.getPRFiles(context, number, configObj)
   const filesDownloadedPromise = response
     .map(async filename => {
       const headRevision = await apiHelper.getContents(context, filename, ref, pullRequest.head)