feat(service-provider-core): allow replset spec in --host MONGOSH-512 (#823)

Author: addaleax

packages/cli-repl/test/e2e-direct.spec.ts

@@ -150,6 +150,34 @@ describe('e2e direct connection', () => {
           shell.assertContainsOutput(`me: '${await rs0.hostport()}'`);
           shell.assertContainsOutput(`setName: '${replSetId}'`);
         });
+        it('when specifying multiple seeds through --host', async() => {
+          const hostlist = replSetId + '/' + await rs2.hostport() + ',' + await rs1.hostport() + ',' + await rs0.hostport();
+          const shell = TestShell.start({ args: ['--host', hostlist] });
+          await shell.waitForPrompt();
+          await shell.executeLine('db.isMaster()');
+          await shell.executeLine('({ dbname: db.getName() })');
+          shell.assertContainsOutput('ismaster: true');
+          shell.assertContainsOutput(`me: '${await rs0.hostport()}'`);
+          shell.assertContainsOutput(`setName: '${replSetId}'`);
+          shell.assertContainsOutput("dbname: 'test'");
+        });
+        it('when specifying multiple seeds through --host with a db name', async() => {
+          const hostlist = replSetId + '/' + await rs2.hostport() + ',' + await rs1.hostport() + ',' + await rs0.hostport();
+          const shell = TestShell.start({ args: ['--host', hostlist, 'admin'] });
+          await shell.waitForPrompt();
+          await shell.executeLine('db.isMaster()');
+          await shell.executeLine('({ dbname: db.getName() })');
+          shell.assertContainsOutput('ismaster: true');
+          shell.assertContainsOutput(`me: '${await rs0.hostport()}'`);
+          shell.assertContainsOutput(`setName: '${replSetId}'`);
+          shell.assertContainsOutput("dbname: 'admin'");
+        });
+        it('when specifying multiple seeds through --host with a wrong replsetid', async() => {
+          const hostlist = 'wrongreplset/' + await rs2.hostport() + ',' + await rs1.hostport() + ',' + await rs0.hostport();
+          const shell = TestShell.start({ args: ['--host', hostlist, 'admin?serverSelectionTimeoutMS=2000'] });
+          await shell.waitForExit();
+          shell.assertContainsOutput('MongoServerSelectionError');
+        });
 
         it('lists collections and dbs using show by default', async() => {
           const shell = TestShell.start({ args: [`${await rs1.connectionString()}`] });

packages/service-provider-core/src/uri-generator.spec.ts

@@ -335,4 +335,16 @@ describe('uri-generator.generate-uri', () => {
       expect.fail('expected error');
     });
   });
+
+  context('when the --host option contains a replica set', () => {
+    it('returns a URI for the hosts and ports specified in --host', () => {
+      const options = { host: 'replsetname/host1:123,host2,host3:456,' };
+      expect(generateUri(options)).to.equal('mongodb://host1:123,host2,host3:456/test?replicaSet=replsetname');
+    });
+
+    it('returns a URI for the hosts and ports specified in --host and database name', () => {
+      const options = { host: 'replsetname/host1:123,host2,host3:456', _: ['admin'] };
+      expect(generateUri(options)).to.equal('mongodb://host1:123,host2,host3:456/admin?replicaSet=replsetname');
+    });
+  });
 });

packages/service-provider-core/src/uri-generator.ts

@@ -141,6 +141,18 @@ function generateUri(options: CliOptions): string {
 function generateUriNormalized(options: CliOptions): ConnectionString {
   const uri = options._?.[0];
 
+  // If the --host argument contains /, it has the format
+  // <replSetName>/<hostname1><:port>,<hostname2><:port>,<...>
+  const replSetHostMatch = (options.host ?? '').match(
+    /^(?<replSetName>[^/]+)\/(?<hosts>([A-Za-z0-9.-]+(:\d+)?,?)+)$/);
+  if (replSetHostMatch) {
+    const { replSetName, hosts } = replSetHostMatch.groups as { replSetName: string, hosts: string };
+    const connectionString = new ConnectionString(`${Scheme.Mongo}replacemeHost/${uri ?? DEFAULT_DB}`);
+    connectionString.hosts = hosts.split(',').filter(host => host.trim());
+    connectionString.searchParams.set('replicaSet', replSetName);
+    return addShellConnectionStringParameters(connectionString);
+  }
+
   // There is no URI provided, use default 127.0.0.1:27017
   if (!uri) {
     return new ConnectionString(`${Scheme.Mongo}${generateHost(options)}:${generatePort(options)}/?directConnection=true`);