Merge pull request #3393 from trufflesuite/add-subcommands

Enhancement: Subcommands and Truffle DB Serve functionality

packages/core/lib/commands/db/commands/serve.js

@@ -0,0 +1,31 @@
+const command = {
+  command: "serve",
+  description: "Start Truffle's GraphQL UI playground",
+  builder: {},
+  help: {
+    usage: "truffle db serve",
+    options: []
+  },
+
+  /* This command does starts an express derived server that invokes
+   * `process.exit()` on SIGINT. As a result there is no need to invoke
+   * truffle's own `process.exit()` which is triggered by invoking the `done`
+   * callback.
+   *
+   * Todo: blacklist this command for REPLs
+   */
+  run: async function (argv) {
+    const Config = require("@truffle/config");
+    const { playgroundServer } = require("@truffle/db");
+
+    const config = Config.detect(argv);
+    const port = (config.db && config.db.port) || 4444;
+
+    const { url } = await playgroundServer(config).listen({ port });
+
+    console.log(`🚀 Playground listening at ${url}`);
+    console.log(`ℹ  Press Ctrl-C to exit`);
+  }
+};
+
+module.exports = command;

packages/core/lib/commands/db/index.js

@@ -0,0 +1,47 @@
+const OS = require("os");
+const serveCommand = require("./commands/serve");
+
+const usage =
+  "truffle db <sub-command> [options]" +
+  OS.EOL +
+  OS.EOL +
+  "  Available sub-commands: " +
+  OS.EOL +
+  OS.EOL +
+  "  serve \tStart the GraphQL server" +
+  OS.EOL;
+
+const command = {
+  command: "db",
+  description: "Database interface commands",
+  builder: function (yargs) {
+    return yargs.commandDir("commands").demandCommand();
+  },
+
+  subCommands: {
+    serve: {
+      help: serveCommand.help,
+      description: serveCommand.description
+    }
+  },
+
+  help: {
+    usage,
+    options: []
+  },
+
+  run: function (args, done) {
+    const [subCommand] = args._;
+    switch (subCommand) {
+      case "serve":
+        serveCommand.run(args, done);
+        break;
+
+      default:
+        console.log(`Unknown command: ${subCommand}`);
+        done();
+    }
+  }
+};
+
+module.exports = command;

packages/core/lib/commands/help.js

@@ -19,9 +19,10 @@ var command = {
       return callback();
     }
     var selectedCommand = options._[0];
+    var subCommand = options._[1];
 
     if (commands[selectedCommand]) {
-      this.displayCommandHelp(selectedCommand);
+      this.displayCommandHelp(selectedCommand, subCommand);
       return callback();
     } else {
       console.log(`\n  Cannot find the given command '${selectedCommand}'`);
@@ -33,12 +34,22 @@ var command = {
       return callback();
     }
   },
-  displayCommandHelp: function (selectedCommand) {
+  displayCommandHelp: function (selectedCommand, subCommand) {
     let commands = require("./index");
-    var commandHelp = commands[selectedCommand].help;
+    let commandHelp, commandDescription;
+
+    const chosenCommand = commands[selectedCommand];
+
+    if (subCommand && chosenCommand.subCommands[subCommand]) {
+      commandHelp = chosenCommand.subCommands[subCommand].help;
+      commandDescription = chosenCommand.subCommands[subCommand].description;
+    } else {
+      commandHelp = chosenCommand.help;
+      commandDescription = chosenCommand.description;
+    }
 
     console.log(`\n  Usage:        ${commandHelp.usage}`);
-    console.log(`  Description:  ${commands[selectedCommand].description}`);
+    console.log(`  Description:  ${commandDescription}`);
 
     if (commandHelp.options.length > 0) {
       console.log(`  Options: `);

packages/core/lib/commands/index.js

@@ -4,6 +4,7 @@ module.exports = {
   config: require("./config"),
   console: require("./console"),
   create: require("./create"),
+  db: require("./db"),
   debug: require("./debug"),
   deploy: require("./deploy"),
   develop: require("./develop"),