bagofcli.js

"use strict";
import _ from "lodash";
import async from "async";
import chalk from "chalk";
import child from "child_process";
import colors from "colors";
import { program as commander } from "commander";
import fs from "fs";
import iz from "iz";
import p from "path";
import inquirer from "inquirer";
import util from "util";
import validators from "iz/lib/validators.js";
import wrench from "wrench-sui";
import yaml from "yaml-js";

/**
 * bagofcli module.
 *
 * @module bagofcli
 */

/**
 * Parse command line arguments and execute actions based on the specified commands.
 * Uses commander.js to provide -V / --version to be displayed version number,
 * and -h / --help to be displayed help info.
 *
 * @param {string} base Base directory where the client module is located.
 * Used as the root directory to read the command file and package.json file.
 * Ideally this is the client's `__dirname`.
 * @param {Object} actions Action functions for commands in the form
 * `{ command: { action: function () {} } }`.
 * The command name in `actions` is mapped to the command name specified in `commandFile`.
 * @param {Object} [opts] Optional settings.
 * @param {string} [opts.commandFile='conf/commands.json'] Relative path to the command file from `base`.
 * @returns {void}
 */
function command(base, actions, opts) {
  actions = actions || {};
  opts = opts || {};
  // commander keeps registered subcommands across invocations on program singleton,
  // so clear command list before registering command definitions for this invocation.
  commander.commands = [];

  const commands = JSON.parse(
      fs.readFileSync(
        p.join(base, opts.commandFile || "../conf/commands.json"),
      ),
    ),
    pkg = JSON.parse(fs.readFileSync(p.join(base, "../package.json")));

  if (actions.commands && commands.commands) {
    _.each(actions.commands, function (command, name) {
      if (commands.commands[name]) {
        commands.commands[name].action = command.action;
      }
    });
  }

  commander.version(pkg.version);

  if (commands.options) {
    _.each(commands.options, function (option) {
      commander.option(option.arg, option.desc, option.action);
    });
  }

  _.each(commands.commands, function (command, name) {
    const program = commander
      .command(name)
      .description(command.desc)
      .allowExcessArguments(true);

    _.each(command.options, function (option) {
      program.option(option.arg, option.desc, option.action);
    });

    if (command.action) {
      program.action(function (...args) {
        command.action(args[args.length - 1]);
      });
    }
  });

  _preCommand(commands.commands);

  commander.parse(process.argv);

  // NOTE: commander.args is populated by commander#parse,
  // hence _postCommand relies on commander#parse finishing without exiting or throwing error,
  // otherwise _postCommand won't be executed
  _postCommand(commander, commands.commands, commands.options);
}

// Pre-command tasks:
// - if --help flag is specified, append examples after standard help output
/**
 * Register a help handler that prints command examples after the default help output.
 *
 * @param {Object} commands Command configuration map.
 * @returns {void}
 * @private
 */
function _preCommand(commands) {
  commander.on("--help", function () {
    let hasExample = _.map(_.values(commands), "examples").filter((elem) => {
      return elem !== undefined;
    });
    if (hasExample.length > 0) {
      hasExample = hasExample.reduce((a, b) => {
        return a.concat(b);
      });
    }
    hasExample = hasExample.length > 0;

    if (hasExample) {
      console.log("  Examples:\n");

      Object.keys(commands).forEach((command) => {
        if (!_.isEmpty(commands[command].examples)) {
          console.log("    %s:", command);
          commands[command].examples.forEach((example) => {
            console.log("      %s", example);
          });
        }
      });
    }
  });
}

// Post-command tasks:
// - if there's no command, display help then exit
// - if command is unknown, display error message then exit
// - if there's command, validate arguments and options then exit
/**
 * Validate command arguments and options after commander parsing.
 *
 * @param {Object} commanderArg Commander instance after parsing.
 * @param {Object} commandsConfig Command configuration map.
 * @param {Array<Object>} [globalOptsConfig] Global option configuration list.
 * @returns {void}
 * @private
 */
function _postCommand(commanderArg, commandsConfig, globalOptsConfig) {
  const commanderArgs = commanderArg.args;

  // add custom validator required which checks if value is not empty
  validators.required = function (value) {
    return !validators.empty(value);
  };

  function _validate(value, name, desc) {
    return function (rule) {
      iz({ value: value, validators: validators });
      if (Object.keys(validators).indexOf(rule) !== -1) {
        const isValid = validators[rule](value);
        if (isValid === null || isValid === false) {
          exit(
            new Error(
              util.format("Invalid %s: <%s> must be %s", desc, name, rule),
            ),
          );
        }
      } else {
        exit(new Error(util.format("Invalid %s rule: %s", desc, rule)));
      }
    };
  }

  /**
   * Resolve an option value from a Commander command instance.
   *
   * Newer Commander versions expose parsed values via opts(), while older behavior
   * may expose values directly as command properties. This helper checks opts()
   * first, then falls back to direct property access for compatibility.
   *
   * @param {Object} commandArg Commander command instance.
   * @param {string} arg Option argument definition.
   * @returns {string|undefined} Parsed option value.
   * @private
   */
  function _getOptionValue(commandArg, arg) {
    const argMatch = arg.match(/<.*?>|\[.*?\]/);
    if (!argMatch) {
      return undefined;
    }
    const name = argMatch[0].replace(/[<>\[\]]/g, "");
    if (commandArg && typeof commandArg.opts === "function") {
      const commandArgOpts = commandArg.opts();
      if (commandArgOpts && commandArgOpts[name] !== undefined) {
        return commandArgOpts[name];
      }
    }
    return commandArg ? commandArg[name] : undefined;
  }

  if (!commanderArgs || commanderArgs.length === 0) {
    return;

    // } else if (commanderArgs.length === 1) {
    //   // having a single arg
    //   // which means that the command is executed without args, hence display help menu
    //   // NOTE: this check is needed because for some reason commander.args
    //   // also returns empty array when one of the args is an opt (-- prefixed)
    //   if (process.argv.length === 2) {
    //     commander.help();
    //   }
  } else {
    const commandName = commanderArgs[0],
      commandArgs = commanderArgs.slice(1, commanderArgs.length),
      commandConfigArgs = commandsConfig[commandName]
        ? commandsConfig[commandName].args
        : undefined,
      commandConfigArgsMandatory = _.filter(commandConfigArgs, function (arg) {
        return !arg.optional;
      }),
      commandConfigOpts = commandsConfig[commandName]
        ? commandsConfig[commandName].options
        : undefined;

    // Unknown command error if the command name doesn't exist in the commands configuration
    if (Object.keys(commandsConfig).indexOf(commandName) === -1) {
      exit(
        new Error(
          util.format(
            "Unknown command: %s, use --help for more info",
            commandName,
          ),
        ),
      );
    } else if (commandConfigArgs && commandConfigArgs.length > 0) {
      const programName =
        typeof commanderArg.name === "function"
          ? commanderArg.name()
          : commanderArg._name;

      // display usage info when mandatory arguments don't exist
      // due to arguments being positional, then comparing the lengths is good enough
      if (commandConfigArgsMandatory.length !== commandArgs.length) {
        exit(
          new Error(
            util.format(
              "Usage: %s %s %s",
              programName,
              commandName,
              commandConfigArgs
                .map((arg) => {
                  return util.format(arg.optional ? "[%s]" : "<%s>", arg.name);
                })
                .join(" "),
            ),
          ),
        );
      } else {
        // validate arguments as configured in commands setup
        for (let i = 0, ln = commandConfigArgs.length; i < ln; i += 1) {
          if (!commandConfigArgs[i].optional) {
            // first arg from Commander is the command, the rest are that command's arguments
            commandConfigArgs[i].rules.forEach(
              _validate(
                commanderArgs[i + 1],
                commandConfigArgs[i].name,
                "argument",
              ),
            );
          }
        }
      }
    }

    // validate command opts as configured in commands setup
    if (commandConfigOpts) {
      commandConfigOpts.forEach((commandOpt) => {
        if (commandOpt.rules) {
          const name = commandOpt.arg,
            value = _getOptionValue(commanderArg, name);
          commandOpt.rules.forEach(_validate(value, name, "option"));
        }
      });
    }

    // validate global opts as configured in commands setup
    if (globalOptsConfig) {
      globalOptsConfig.forEach((globalOptConfig) => {
        if (globalOptConfig.rules) {
          const name = globalOptConfig.arg,
            value = _getOptionValue(commanderArg.parent, name);
          globalOptConfig.rules.forEach(_validate(value, name, "option"));
        }
      });
    }
  }
}

/**
 * Execute a one-liner command.
 *
 * The output emitted on stderr and stdout of the child process will be written to process.stdout
 * and process.stderr of this process.
 *
 * Fallthrough is handy in situation where there are multiple execs running in sequence/parallel,
 * and they all have to be executed regardless of success/error on either one of them.
 *
 * @param {string} command Command to execute.
 * @param {boolean} fallthrough Allow error to be camouflaged as a non-error.
 * @param {Function} cb Standard `cb(err, result)` callback.
 * @returns {void}
 */
function exec(command, fallthrough, cb) {
  execute(
    command,
    fallthrough,
    false,
    function (err, stdOutOuput, stdErrOuput, result) {
      // drop stdOutOuput and stdErrOuput parameters to keep exec backwards compatible.
      cb(err, result);
    },
  );
}

/**
 * Execute a one-liner command and collect the output.
 *
 * The output emitted on stderr and stdout of the child process will be
 * collected and passed on to the given callback.
 *
 * Fallthrough is handy in situation where there are multiple execs running in sequence/parallel,
 * and they all have to be executed regardless of success/error on either one of them.
 *
 * @param {string} command Command to execute.
 * @param {boolean} fallthrough Allow error to be camouflaged as a non-error.
 * @param {Function} cb `(err, stdOutOutput, stdErrOutput, result)` callback.
 * @returns {void}
 */
function execAndCollect(command, fallthrough, cb) {
  execute(command, fallthrough, true, cb);
}

// not exported
/**
 * Execute a one-liner command.
 *
 * The output emitted on stderr and stdout of the child process will either be written to
 * process.stdout and process.stderr of this process or collected and passed on to the
 * given callback, depending on collectOutput.
 *
 * Fallthrough is handy in situation where there are multiple execs running in sequence/parallel,
 * and they all have to be executed regardless of success/error on either one of them.
 *
 * @param {string} command Command to execute.
 * @param {boolean} fallthrough Allow error to be camouflaged as a non-error.
 * @param {boolean} collectOutput Pass child output to the callback instead of writing it.
 * @param {Function} cb `(err, stdOutOutput, stdErrOutput, result)` callback.
 * @returns {void}
 * @private
 */
function execute(command, fallthrough, collectOutput, cb) {
  let collectedStdOut = "";
  let collectedStdErr = "";

  const _exec = child.exec(command, function (err) {
    let result;
    if (err && fallthrough) {
      // camouflage error to allow other execs to keep running
      result = err;
      err = null;
    }
    cb(err, collectedStdOut, collectedStdErr, result);
  });

  _exec.stdout.on("data", function (data) {
    if (collectOutput) {
      collectedStdOut += data.toString().trim();
    } else {
      process.stdout.write(colors.green(data.toString()));
    }
  });

  _exec.stderr.on("data", function (data) {
    if (collectOutput) {
      collectedStdErr += data.toString().trim();
    } else {
      process.stderr.write(colors.red(data.toString()));
    }
  });
}

/**
 * Handle process exit based on the existence of error.
 * This is handy for command-line tools to use as the final callback.
 * Exit status code 1 indicates an error, exit status code 0 indicates a success.
 * Error message will be logged to the console. Result object is only used for convenient debugging.
 * Exit is also called with a second method in the signature called 'result', but it's not declared
 * here due to not being used when there is no error and this function simply exits with code 0
 *
 * @param {Error} err Error object existence indicates the occurrence of an error.
 * @returns {void}
 */
function exit(err) {
  if (err) {
    console.error(colors.red(err.message || JSON.stringify(err)));
    process.exit(1);
  } else {
    process.exit(0);
  }
}

/**
 * A higher order function that returns a process exit callback,
 * with error and success callbacks to handle error and result accordingly.
 * Exit status code 1 indicates an error, exit status code 0 indicates a success.
 *
 * @param {Function} [errorCb] Error callback, defaults to logging to console error.
 * @param {Function} [successCb] Success callback, defaults to logging to console log.
 * @returns {Function} Exit callback.
 */
function exitCb(errorCb, successCb) {
  if (!errorCb) {
    errorCb = function (err) {
      console.error(colors.red(err.message || JSON.stringify(err)));
    };
  }

  if (!successCb) {
    successCb = function (result) {
      console.log(colors.green(result.toString()));
    };
  }

  return function (err, result) {
    if (err) {
      errorCb(err);
      process.exit(1);
    } else {
      successCb(result);
      process.exit(0);
    }
  };
}

/**
 * Get an array of files contained in specified items.
 * When a directory is specified, all files contained within that directory and its sub-directories will be included.
 *
 * @param {Array<string>} items Array of files and/or directories.
 * @param {Object} [opts] Optional settings.
 * @param {string} [opts.match] Regular expression to match against the file name.
 * @returns {Array<string>} All files.
 */
function files(items, opts) {
  opts = opts || {};
  const data = [];

  function addMatch(item) {
    if (
      opts.match === undefined ||
      (opts.match && item.match(new RegExp(opts.match)))
    ) {
      data.push(item);
    }
  }

  items.forEach((item) => {
    const stat = fs.statSync(item);

    if (stat.isFile()) {
      addMatch(item);
    } else if (stat.isDirectory()) {
      const _items = wrench.readdirSyncRecursive(item);
      _items.forEach((_item) => {
        _item = p.join(item, _item);
        if (fs.statSync(_item).isFile()) {
          addMatch(_item);
        }
      });
    }
  });
  return data;
}

/**
 * Lookup config values for the specified keys in the following order:
 * - environment variable
 * - if optional file is specified, then check for the value inside the file
 *   file type depends on extension file
 * - if optional enablePrompt is set to true, then prompt the user for config value
 *
 * @param {Array<string>|string} keys Configuration keys to look up.
 * @param {Object} opts Optional settings.
 * @param {string} [opts.file] File name to look up configuration values from.
 * @param {boolean} [opts.prompt=false] Prompt the user for missing configuration values.
 * @param {Function} cb Standard `cb(err, result)` callback.
 * @returns {void}
 */
function lookupConfig(keys, opts, cb) {
  if (!Array.isArray(keys)) {
    keys = [keys];
  }
  opts.prompt = opts.prompt || false;

  // parse values from configuration file if supplied
  const file = {};
  if (opts.file) {
    const content = this.lookupFile(opts.file);
    if (opts.file.match(/\.json$/)) {
      file.json = JSON.parse(content);
    } else if (opts.file.match(/\.ya?ml$/)) {
      file.yaml = yaml.load(content);
    } else {
      throw new Error("Configuration file extension is not supported");
    }
  }

  function lookup(key, cb) {
    if (process.env[key]) {
      cb(process.env[key]);
    } else if (file.json) {
      cb(file.json[key]);
    } else if (file.yaml) {
      cb(file.yaml[key]);
    } else {
      cb(undefined);
    }
  }

  // lookup for values in environment variables and configuration file
  const tasks = {};
  keys.forEach((key) => {
    tasks[key] = function (cb) {
      lookup(key, function (result) {
        cb(null, result);
      });
    };
  });

  async.parallel(tasks, function (err, results) {
    if (opts.prompt) {
      // prompt users for any keys that don't yet have any value from
      // environment variables and configuration file
      const promptQuestions = [];
      keys.forEach((key) => {
        if (results[key] === undefined) {
          const promptQuestion = {
            name: key,
            message: key,
            default: false,
          };
          if (key.toLowerCase().indexOf("password") >= 0) {
            promptQuestion.type = "input";
          } else {
            promptQuestion.type = "password";
          }
          promptQuestions.push(promptQuestion);
        }
      });
      if (promptQuestions.length > 0) {
        inquirer.prompt(promptQuestions).then((promptAnswers) => {
          results = _.extend(results, promptAnswers);
          cb(err, results);
        });
      } else {
        cb(err, results);
      }
    } else {
      cb(err, results);
    }
  });
}

/**
 * Synchronously read file based on these rules:
 * - if path is absolute, then check file at absolute path first
 * - if path is relative, then check file at current working directory
 * - if none of the above exists, check file at user home directory
 * - if none exists, throw an error
 * This allows simple file lookup which allows various locations.
 *
 * @param {string} file File name to read.
 * @param {Object} [opts] Optional settings.
 * @param {string} [opts.platform] Platform override for tests.
 * @returns {string} File content.
 */
function lookupFile(file, opts) {
  opts = opts || {};
  let data;
  const platform = opts.platform || process.platform,
    baseDir = file.match(/^\//) ? p.dirname(file) : process.cwd(),
    homeDir = process.env[platform === "win32" ? "USERPROFILE" : "HOME"],
    files = _.map([baseDir, homeDir], function (dir) {
      return p.join(dir, file.match(/^\//) ? p.basename(file) : file);
    });

  for (let i = 0, ln = files.length; i < ln; i += 1) {
    try {
      data = fs.readFileSync(files[i]);
      break;
    } catch (err) {
      // do nothing when unable to read file
    }
  }

  if (data) {
    return data;
  } else {
    throw new Error("Unable to lookup file in " + files.join(", "));
  }
}

/**
 * Execute a command with an array of arguments.
 * E.g. command: make, arguments: -f somemakefile target1 target2 target3
 *      will be executed as: make -f somemakefile target1 target2 target3
 * NOTE: process.stdout.write and process.stderr.write are used because console.log adds a newline
 *
 * @param {string} command Command to execute.
 * @param {Array<string>} args Command arguments.
 * @param {Function} cb Standard `cb(err, result)` callback.
 * @returns {void}
 */
function spawn(command, args, cb) {
  const _spawn = child.spawn(command, args);

  _spawn.stdout.on("data", function (data) {
    process.stdout.write(colors.green(data.toString()));
  });

  _spawn.stderr.on("data", function (data) {
    process.stderr.write(colors.red(data.toString()));
  });

  _spawn.on("exit", function (code) {
    cb(code !== 0 ? new Error(code) : undefined, code);
  });
}

/**
 * Displays log step heading message on the console.
 *
 * @param {string} message Heading message to be displayed.
 * @param {Object} [opts] Optional settings.
 * @param {Array<string>} [opts.labels] Labels to be displayed before the message.
 * @returns {void}
 */
function logStepHeading(message, opts) {
  opts = opts || {};
  const messageText = chalk.bold.cyan(message);
  if (opts.labels && Array.isArray(opts.labels)) {
    const labelsText = chalk.bgMagenta(opts.labels.join(" | "));
    console.log("%s %s", labelsText, messageText);
  } else {
    console.log("%s", messageText);
  }
}

/**
 * Displays log step item success message on the console.
 *
 * @param {string} message Success message to be displayed.
 * @param {Object} [opts] Optional settings.
 * @param {Array<string>} [opts.labels] Labels to be displayed before the message.
 * @returns {void}
 */
function logStepItemSuccess(message, opts) {
  opts = opts || {};
  const messageText = chalk.green(message);
  if (opts.labels && Array.isArray(opts.labels)) {
    const labelsText = chalk.bgMagenta(opts.labels.join(" | "));
    console.log("  * %s %s", labelsText, messageText);
  } else {
    console.log("  * %s", messageText);
  }
}

/**
 * Displays log step item warning message on the console.
 *
 * @param {string} message Warning message to be displayed.
 * @param {Object} [opts] Optional settings.
 * @param {Array<string>} [opts.labels] Labels to be displayed before the message.
 * @returns {void}
 */
function logStepItemWarning(message, opts) {
  opts = opts || {};
  const messageText = chalk.yellow(message);
  if (opts.labels && Array.isArray(opts.labels)) {
    const labelsText = chalk.bgMagenta(opts.labels.join(" | "));
    console.log("  * %s %s", labelsText, messageText);
  } else {
    console.log("  * %s", messageText);
  }
}

/**
 * Displays log step error item error message on the console.
 *
 * @param {string} message Error message to be displayed.
 * @param {Object} [opts] Optional settings.
 * @param {Array<string>} [opts.labels] Labels to be displayed before the message.
 * @returns {void}
 */
function logStepItemError(message, opts) {
  opts = opts || {};
  const messageText = chalk.red(message);
  if (opts.labels && Array.isArray(opts.labels)) {
    const labelsText = chalk.bgMagenta(opts.labels.join(" | "));
    console.error("  * %s %s", labelsText, messageText);
  } else {
    console.error("  * %s", messageText);
  }
}

const exports = {
  command: command,
  _preCommand: _preCommand,
  _postCommand: _postCommand,
  exec: exec,
  execAndCollect: execAndCollect,
  exit: exit,
  exitCb: exitCb,
  files: files,
  lookupConfig: lookupConfig,
  lookupFile: lookupFile,
  spawn: spawn,
  logStepHeading: logStepHeading,
  logStepItemSuccess: logStepItemSuccess,
  logStepItemWarning: logStepItemWarning,
  logStepItemError: logStepItemError,
};

export { exports as default };