introduce inputs.threads flag to analyze action

analyze/action.yml

@@ -4,17 +4,22 @@ author: 'GitHub'
 inputs:
   check_name:
     description: The name of the check run to add text to.
+    required: false
   output:
     description: The path of the directory in which to save the SARIF results
     required: false
     default: '../results'
   upload:
     description: Upload the SARIF file
     required: false
-    default: true
+    default: "true"
   ram:
     description: Override the amount of memory in MB to be used by CodeQL. By default, almost all the memory of the machine is used.
     required: false
+  threads:
+    description: The number of threads to be used by CodeQL.
+    required: false
+    default: "1"
   token:
     default: ${{ github.token }}
   matrix:

src/finalize-db.test.ts

@@ -0,0 +1,58 @@
+import test from "ava";
+import * as os from "os";
+
+import {
+    getMemoryFlag,
+    getThreadsFlag
+} from "./finalize-db";
+
+test('getMemoryFlag() should return the correct --ram flag', t => {
+
+    const totalMem = os.totalmem() / (1024 * 1024);
+
+    const tests = {
+        "": `--ram=${totalMem - 256}`,
+        "512": "--ram=512",
+    };
+
+    for (const [input, expectedFlag] of Object.entries(tests)) {
+
+        process.env['INPUT_RAM'] = input;
+
+        const flag = getMemoryFlag();
+        t.deepEqual(flag, expectedFlag);
+    }
+});
+
+test('getMemoryFlag() throws if the ram input is < 0 or NaN', t => {
+    for (const input of ["-1", "hello!"]) {
+        process.env['INPUT_RAM'] = input;
+        t.throws(getMemoryFlag);
+    }
+});
+
+test('getThreadsFlag() should return the correct --threads flag', t => {
+
+    const numCpus = os.cpus().length;
+
+    const tests = {
+        "0": "--threads=0",
+        "1": "--threads=1",
+        [`${numCpus + 1}`]: `--threads=${numCpus}`
+    };
+
+    for (const [input, expectedFlag] of Object.entries(tests)) {
+
+        process.env['INPUT_THREADS'] = input;
+
+        const flag = getThreadsFlag();
+        t.deepEqual(flag, expectedFlag);
+    }
+});
+
+test('getThreadsFlag() throws if the ram input is < 0 or NaN', t => {
+    for (const input of ["-1", "hello!"]) {
+        process.env['INPUT_THREADS'] = input;
+        t.throws(getThreadsFlag);
+    }
+});

src/finalize-db.ts

@@ -20,7 +20,7 @@ import * as util from './util';
  *
  * Format is a map from language to an array of path suffixes of .ql files.
  */
-const DISABLED_BUILTIN_QUERIES: {[language: string]: string[]} = {
+const DISABLED_BUILTIN_QUERIES: { [language: string]: string[]; } = {
   'csharp': [
     'ql/src/Security Features/CWE-937/VulnerablePackage.ql',
     'ql/src/Security Features/CWE-451/MissingXFrameOptions.ql',
@@ -32,7 +32,7 @@ function queryIsDisabled(language, query): boolean {
     .some(disabledQuery => query.endsWith(disabledQuery));
 }
 
-function getMemoryFlag(): string {
+export function getMemoryFlag(): string {
   let memoryToUseMegaBytes: number;
   const memoryToUseString = core.getInput("ram");
   if (memoryToUseString) {
@@ -49,6 +49,22 @@ function getMemoryFlag(): string {
   return "--ram=" + Math.floor(memoryToUseMegaBytes);
 }
 
+export function getThreadsFlag(): string {
+  let numThreads = 1;
+  const numThreadsString = core.getInput("threads");
+  if (numThreadsString) {
+    numThreads = Number(numThreadsString);
+    if (Number.isNaN(numThreads) || numThreads < 0) {
+      throw new Error(`Invalid threads setting "${numThreadsString}", specified.`);
+    }
+    const maxThreads = os.cpus().length;
+    if (numThreads > maxThreads) {
+      numThreads = maxThreads;
+    }
+  }
+  return `--threads=${numThreads}`;
+}
+
 async function createdDBForScannedLanguages(codeqlCmd: string, databaseFolder: string) {
   const scannedLanguages = process.env[sharedEnv.CODEQL_ACTION_SCANNED_LANGUAGES];
   if (scannedLanguages) {
@@ -93,14 +109,14 @@ async function finalizeDatabaseCreation(codeqlCmd: string, databaseFolder: strin
 interface ResolveQueriesOutput {
   byLanguage: {
     [language: string]: {
-      [queryPath: string]: {}
-    }
+      [queryPath: string]: {};
+    };
   };
   noDeclaredLanguage: {
-    [queryPath: string]: {}
+    [queryPath: string]: {};
   };
   multipleDeclaredLanguages: {
-    [queryPath: string]: {}
+    [queryPath: string]: {};
   };
 }
 
@@ -116,11 +132,11 @@ async function runResolveQueries(codeqlCmd: string, queries: string[]): Promise<
 
   await exec.exec(
     codeqlCmd, [
-      'resolve',
-      'queries',
-      ...queries,
-      '--format=bylanguage'
-    ],
+    'resolve',
+    'queries',
+    ...queries,
+    '--format=bylanguage'
+  ],
     options);
 
   return JSON.parse(output);
@@ -201,6 +217,7 @@ async function runQueries(codeqlCmd: string, databaseFolder: string, sarifFolder
       'database',
       'analyze',
       getMemoryFlag(),
+      getThreadsFlag(),
       path.join(databaseFolder, database),
       '--format=sarif-latest',
       '--output=' + sarifFile,