339 lines
9.5 KiB
JavaScript

var util = require('util');
var path = require('path');
var EE = require('events').EventEmitter;
var extend = require('extend');
var resolve = require('resolve');
var flaggedRespawn = require('flagged-respawn');
var isPlainObject = require('is-plain-object').isPlainObject;
var fined = require('fined');
var findCwd = require('./lib/find_cwd');
var arrayFind = require('./lib/array_find');
var findConfig = require('./lib/find_config');
var fileSearch = require('./lib/file_search');
var needsLookup = require('./lib/needs_lookup');
var parseOptions = require('./lib/parse_options');
var silentRequire = require('./lib/silent_require');
var buildConfigName = require('./lib/build_config_name');
var registerLoader = require('./lib/register_loader');
var getNodeFlags = require('./lib/get_node_flags');
function isString(val) {
return typeof val === 'string';
}
function Liftoff(opts) {
EE.call(this);
extend(this, parseOptions(opts));
}
util.inherits(Liftoff, EE);
Liftoff.prototype.requireLocal = function (moduleName, basedir) {
try {
this.emit('preload:before', moduleName);
var result = require(resolve.sync(moduleName, { basedir: basedir }));
this.emit('preload:success', moduleName, result);
return result;
} catch (e) {
this.emit('preload:failure', moduleName, e);
}
};
Liftoff.prototype.buildEnvironment = function (opts) {
opts = opts || {};
// get modules we want to preload
var preload = opts.preload || [];
// ensure items to preload is an array
if (!Array.isArray(preload)) {
preload = [preload];
}
// make a copy of search paths that can be mutated for this run
var searchPaths = this.searchPaths.slice();
// store the instance configName to use in closures without access to `this`
var configName = this.configName;
// calculate current cwd
var cwd = findCwd(opts);
var exts = this.extensions;
var eventEmitter = this;
function findAndRegisterLoader(pathObj, defaultObj) {
var found = fined(pathObj, defaultObj);
if (!found) {
return null;
}
if (isPlainObject(found.extension)) {
registerLoader(eventEmitter, found.extension, found.path, cwd);
}
return found.path;
}
function getModulePath(cwd, xtends) {
// If relative, we need to use fined to look up the file. If not, assume a node_module
if (needsLookup(xtends)) {
var defaultObj = { cwd: cwd, extensions: exts };
// Using `xtends` like this should allow people to use a string or any object that fined accepts
var foundPath = findAndRegisterLoader(xtends, defaultObj);
if (!foundPath) {
var name;
if (typeof xtends === 'string') {
name = xtends;
} else {
name = xtends.path || xtends.name;
}
var msg = 'Unable to locate one of your extends.';
if (name) {
msg += ' Looking for file: ' + path.resolve(cwd, name);
}
throw new Error(msg);
}
return foundPath;
}
return xtends;
}
var visited = {};
function loadConfig(cwd, xtends, preferred) {
var configFilePath = getModulePath(cwd, xtends);
if (visited[configFilePath]) {
throw new Error(
'We encountered a circular extend for file: ' +
configFilePath +
'. Please remove the recursive extends.'
);
}
var configFile;
try {
configFile = require(configFilePath);
} catch (e) {
// TODO: Consider surfacing the `require` error
throw new Error(
'Encountered error when loading config file: ' + configFilePath
);
}
// resolve something like `{ gulpfile: "./abc.xyz" }` to the absolute path
// based on the path of the configFile
if (Object.prototype.hasOwnProperty.call(configFile, configName)) {
if (isString(configFile[configName])) {
configFile[configName] = path.resolve(path.dirname(configFilePath), configFile[configName]);
}
}
visited[configFilePath] = true;
if (configFile && configFile.extends) {
var nextCwd = path.dirname(configFilePath);
return loadConfig(nextCwd, configFile.extends, configFile);
}
// Always extend into an empty object so we can call `delete` on `config.extends`
var config = extend(true /* deep */, {}, configFile, preferred);
delete config.extends;
return config;
}
var configFiles = [];
if (Array.isArray(this.configFiles)) {
configFiles = this.configFiles.map(function (pathObj) {
var defaultObj = { cwd: cwd, extensions: exts };
return findAndRegisterLoader(pathObj, defaultObj);
});
}
var config = configFiles.map(function (startingLocation) {
var defaultConfig = {};
if (!startingLocation) {
return defaultConfig;
}
return loadConfig(cwd, startingLocation, defaultConfig);
});
var configPathOverride = arrayFind(config, function (cfg) {
if (Object.prototype.hasOwnProperty.call(cfg, configName)) {
if (isString(cfg[configName])) {
return cfg[configName];
}
}
});
var additionPreloads = arrayFind(config, function (cfg) {
if (Object.prototype.hasOwnProperty.call(cfg, 'preload')) {
if (Array.isArray(cfg.preload)) {
if (cfg.preload.every(isString)) {
return cfg.preload;
}
}
if (isString(cfg.preload)) {
return cfg.preload;
}
}
});
// if cwd was provided explicitly, only use it for searching config
if (opts.cwd) {
searchPaths = [cwd];
} else {
// otherwise just search in cwd first
searchPaths.unshift(cwd);
}
// calculate the regex to use for finding the config file
var configNameSearch = buildConfigName({
configName: configName,
extensions: Object.keys(this.extensions),
});
// calculate configPath
var configPath = findConfig({
configNameSearch: configNameSearch,
searchPaths: searchPaths,
configPath: opts.configPath || configPathOverride,
});
// if we have a config path, save the directory it resides in.
var configBase;
if (configPath) {
configBase = path.dirname(configPath);
// if cwd wasn't provided explicitly, it should match configBase
if (!opts.cwd) {
cwd = configBase;
}
}
// TODO: break this out into lib/
// locate local module and package next to config or explicitly provided cwd
var modulePath;
var modulePackage;
try {
var delim = path.delimiter;
var paths = process.env.NODE_PATH ? process.env.NODE_PATH.split(delim) : [];
modulePath = resolve.sync(this.moduleName, {
basedir: configBase || cwd,
paths: paths,
});
modulePackage = silentRequire(fileSearch('package.json', [modulePath]));
} catch (e) {}
// if we have a configuration but we failed to find a local module, maybe
// we are developing against ourselves?
if (!modulePath && configPath) {
// check the package.json sibling to our config to see if its `name`
// matches the module we're looking for
var modulePackagePath = fileSearch('package.json', [configBase]);
modulePackage = silentRequire(modulePackagePath);
if (modulePackage && modulePackage.name === this.moduleName) {
// if it does, our module path is `main` inside package.json
modulePath = path.join(
path.dirname(modulePackagePath),
modulePackage.main || 'index.js'
);
cwd = configBase;
} else {
// clear if we just required a package for some other project
modulePackage = {};
}
}
return {
cwd: cwd,
preload: preload.concat(additionPreloads || []),
completion: opts.completion,
configNameSearch: configNameSearch,
configPath: configPath,
configBase: configBase,
modulePath: modulePath,
modulePackage: modulePackage || {},
configFiles: configFiles,
config: config,
};
};
Liftoff.prototype.handleFlags = function (cb) {
if (typeof this.v8flags === 'function') {
this.v8flags(function (err, flags) {
if (err) {
cb(err);
} else {
cb(null, flags);
}
});
} else {
process.nextTick(
function () {
cb(null, this.v8flags);
}.bind(this)
);
}
};
Liftoff.prototype.prepare = function (opts, fn) {
if (typeof fn !== 'function') {
throw new Error('You must provide a callback function.');
}
process.title = this.processTitle;
var env = this.buildEnvironment(opts);
fn.call(this, env);
};
Liftoff.prototype.execute = function (env, forcedFlags, fn) {
var completion = env.completion;
if (completion && this.completions) {
return this.completions(completion);
}
if (typeof forcedFlags === 'function') {
fn = forcedFlags;
forcedFlags = undefined;
}
if (typeof fn !== 'function') {
throw new Error('You must provide a callback function.');
}
this.handleFlags(
function (err, flags) {
if (err) {
throw err;
}
flags = flags || [];
flaggedRespawn(flags, process.argv, forcedFlags, execute.bind(this));
function execute(ready, child, argv) {
if (child !== process) {
var execArgv = getNodeFlags.fromReorderedArgv(argv);
this.emit('respawn', execArgv, child);
}
if (ready) {
preloadModules(this, env);
registerLoader(this, this.extensions, env.configPath, env.cwd);
fn.call(this, env, argv);
}
}
}.bind(this)
);
};
function preloadModules(inst, env) {
var basedir = env.cwd;
env.preload.filter(toUnique).forEach(function (module) {
inst.requireLocal(module, basedir);
});
}
function toUnique(elem, index, array) {
return array.indexOf(elem) === index;
}
module.exports = Liftoff;