feat(MongoBinaryDownloadUrl): add ability to overwrite distro used

fixes #753

Author: hasezoey

docs/api/config-options.md

@@ -49,6 +49,22 @@ Valid Options are `x64`, `arm64`, ~~`ia32`~~([will be removed in 9.0](../guides/
 
 [See here for what versions are available for what architectures](https://www.mongodb.com/download-center/community/releases/archive)
 
+### DISTRO
+
+| Environment Variable | PackageJson |
+| :------------------: | :---------: |
+|   `MONGOMS_DISTRO`   |  `distro`   |
+
+Option `DISTRO` is used to overwrite the Distribution used instead of the detected one.
+
+Only works for when [`PLATFORM`](#platform) (automatic or manually set) is `linux`.
+
+Format is `distro-release`, both distro and release need to be always defined.
+
+Example: `ubuntu-18.04`
+
+[See here for what versions are available for what distros](https://www.mongodb.com/download-center/community/releases/archive)
+
 ### VERSION
 
 | Environment Variable | PackageJson |

packages/mongodb-memory-server-core/src/util/MongoBinaryDownloadUrl.ts

@@ -5,6 +5,7 @@ import * as semver from 'semver';
 import { isNullOrUndefined } from './utils';
 import { URL } from 'url';
 import {
+  GenericMMSError,
   KnownVersionIncompatibilityError,
   UnknownArchitectureError,
   UnknownPlatformError,
@@ -161,10 +162,14 @@ export class MongoBinaryDownloadUrl implements MongoBinaryDownloadUrlOpts {
 
     // the highest version for "i686" seems to be 3.3
     if (this.arch !== 'i686') {
-      if (!this.os) {
+      if (!this.os && resolveConfig(ResolveConfigVariables.DISTRO)) {
         this.os = await getOS();
       }
 
+      if (resolveConfig(ResolveConfigVariables.DISTRO)) {
+        this.overwriteDistro();
+      }
+
       osString = this.getLinuxOSVersionString(this.os as LinuxOS);
     }
 
@@ -180,6 +185,38 @@ export class MongoBinaryDownloadUrl implements MongoBinaryDownloadUrlOpts {
     return name;
   }
 
+  /**
+   * Parse and apply config option DISTRO
+   */
+  protected overwriteDistro() {
+    const env = resolveConfig(ResolveConfigVariables.DISTRO);
+
+    if (isNullOrUndefined(env)) {
+      return;
+    }
+
+    const split = env.split('-');
+
+    const distro = split[0];
+    const release = split[1];
+
+    if (isNullOrUndefined(distro)) {
+      throw new GenericMMSError('Expected DISTRO option to have a distro like "ubuntu-18.04"');
+    }
+
+    if (isNullOrUndefined(release)) {
+      throw new GenericMMSError(
+        'Expected DISTRO option to have a release like "ubuntu-18.04" (delimited by "-")'
+      );
+    }
+
+    this.os = {
+      os: 'linux',
+      dist: distro,
+      release: release,
+    } as LinuxOS;
+  }
+
   /**
    * Get the version string (with distro)
    * @param os LinuxOS Object

packages/mongodb-memory-server-core/src/util/__tests__/MongoBinaryDownloadUrl.test.ts

@@ -1766,6 +1766,41 @@ describe('MongoBinaryDownloadUrl', () => {
       expect(du.getLegacyVersionString).toHaveBeenCalledTimes(1);
       expect(ret).toBe('');
     });
+
+    describe('wrap config options', () => {
+      const originalEnv = process.env;
+
+      beforeEach(() => {
+        process.env = originalEnv;
+      });
+
+      afterAll(() => {
+        process.env = originalEnv;
+      });
+
+      it('should apply config option DISTRO', async () => {
+        const du = new MongoBinaryDownloadUrl({
+          platform: 'linux',
+          arch: 'x64',
+          version: '5.0.0',
+          os: {
+            os: 'linux',
+            dist: 'unknown',
+            release: '0',
+            codename: 'unknown',
+          },
+        });
+        // @ts-expect-error "overwriteDistro" is protected
+        jest.spyOn(du, 'overwriteDistro');
+
+        process.env[envName(ResolveConfigVariables.DISTRO)] = 'ubuntu-18.04';
+
+        expect((await du.getArchiveNameLinux()).includes('ubuntu1804')).toBeTruthy();
+
+        // @ts-expect-error "overwriteDistro" is protected
+        expect(du.overwriteDistro).toBeCalledTimes(1);
+      });
+    });
   });
 
   describe('translateArch()', () => {

packages/mongodb-memory-server-core/src/util/resolveConfig.ts

@@ -25,6 +25,7 @@ export enum ResolveConfigVariables {
   USE_HTTP = 'USE_HTTP',
   SYSTEM_BINARY_VERSION_CHECK = 'SYSTEM_BINARY_VERSION_CHECK',
   USE_ARCHIVE_NAME_FOR_BINARY_NAME = 'USE_ARCHIVE_NAME_FOR_BINARY_NAME',
+  DISTRO = 'DISTRO',
 }
 
 /** The Prefix for Environmental values */