forked from zhurui/management
381 lines
12 KiB
JavaScript
381 lines
12 KiB
JavaScript
'use strict';
|
|
|
|
const Readable = require('stream').Readable;
|
|
const EventEmitter = require('events').EventEmitter;
|
|
const path = require('path');
|
|
const normalizeOptions = require('./normalize-options');
|
|
const stat = require('./stat');
|
|
const call = require('./call');
|
|
|
|
/**
|
|
* Asynchronously reads the contents of a directory and streams the results
|
|
* via a {@link stream.Readable}.
|
|
*/
|
|
class DirectoryReader {
|
|
/**
|
|
* @param {string} dir - The absolute or relative directory path to read
|
|
* @param {object} [options] - User-specified options, if any (see {@link normalizeOptions})
|
|
* @param {object} internalOptions - Internal options that aren't part of the public API
|
|
* @class
|
|
*/
|
|
constructor (dir, options, internalOptions) {
|
|
this.options = options = normalizeOptions(options, internalOptions);
|
|
|
|
// Indicates whether we should keep reading
|
|
// This is set false if stream.Readable.push() returns false.
|
|
this.shouldRead = true;
|
|
|
|
// The directories to read
|
|
// (initialized with the top-level directory)
|
|
this.queue = [{
|
|
path: dir,
|
|
basePath: options.basePath,
|
|
posixBasePath: options.posixBasePath,
|
|
depth: 0
|
|
}];
|
|
|
|
// The number of directories that are currently being processed
|
|
this.pending = 0;
|
|
|
|
// The data that has been read, but not yet emitted
|
|
this.buffer = [];
|
|
|
|
this.stream = new Readable({ objectMode: true });
|
|
this.stream._read = () => {
|
|
// Start (or resume) reading
|
|
this.shouldRead = true;
|
|
|
|
// If we have data in the buffer, then send the next chunk
|
|
if (this.buffer.length > 0) {
|
|
this.pushFromBuffer();
|
|
}
|
|
|
|
// If we have directories queued, then start processing the next one
|
|
if (this.queue.length > 0) {
|
|
if (this.options.facade.sync) {
|
|
while (this.queue.length > 0) {
|
|
this.readNextDirectory();
|
|
}
|
|
}
|
|
else {
|
|
this.readNextDirectory();
|
|
}
|
|
}
|
|
|
|
this.checkForEOF();
|
|
};
|
|
}
|
|
|
|
/**
|
|
* Reads the next directory in the queue
|
|
*/
|
|
readNextDirectory () {
|
|
let facade = this.options.facade;
|
|
let dir = this.queue.shift();
|
|
this.pending++;
|
|
|
|
// Read the directory listing
|
|
call.safe(facade.fs.readdir, dir.path, (err, items) => {
|
|
if (err) {
|
|
// fs.readdir threw an error
|
|
this.emit('error', err);
|
|
return this.finishedReadingDirectory();
|
|
}
|
|
|
|
try {
|
|
// Process each item in the directory (simultaneously, if async)
|
|
facade.forEach(
|
|
items,
|
|
this.processItem.bind(this, dir),
|
|
this.finishedReadingDirectory.bind(this, dir)
|
|
);
|
|
}
|
|
catch (err2) {
|
|
// facade.forEach threw an error
|
|
// (probably because fs.readdir returned an invalid result)
|
|
this.emit('error', err2);
|
|
this.finishedReadingDirectory();
|
|
}
|
|
});
|
|
}
|
|
|
|
/**
|
|
* This method is called after all items in a directory have been processed.
|
|
*
|
|
* NOTE: This does not necessarily mean that the reader is finished, since there may still
|
|
* be other directories queued or pending.
|
|
*/
|
|
finishedReadingDirectory () {
|
|
this.pending--;
|
|
|
|
if (this.shouldRead) {
|
|
// If we have directories queued, then start processing the next one
|
|
if (this.queue.length > 0 && this.options.facade.async) {
|
|
this.readNextDirectory();
|
|
}
|
|
|
|
this.checkForEOF();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Determines whether the reader has finished processing all items in all directories.
|
|
* If so, then the "end" event is fired (via {@Readable#push})
|
|
*/
|
|
checkForEOF () {
|
|
if (this.buffer.length === 0 && // The stuff we've already read
|
|
this.pending === 0 && // The stuff we're currently reading
|
|
this.queue.length === 0) { // The stuff we haven't read yet
|
|
// There's no more stuff!
|
|
this.stream.push(null);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Processes a single item in a directory.
|
|
*
|
|
* If the item is a directory, and `option.deep` is enabled, then the item will be added
|
|
* to the directory queue.
|
|
*
|
|
* If the item meets the filter criteria, then it will be emitted to the reader's stream.
|
|
*
|
|
* @param {object} dir - A directory object from the queue
|
|
* @param {string} item - The name of the item (name only, no path)
|
|
* @param {function} done - A callback function that is called after the item has been processed
|
|
*/
|
|
processItem (dir, item, done) {
|
|
let stream = this.stream;
|
|
let options = this.options;
|
|
|
|
let itemPath = dir.basePath + item;
|
|
let posixPath = dir.posixBasePath + item;
|
|
let fullPath = path.join(dir.path, item);
|
|
|
|
// If `options.deep` is a number, and we've already recursed to the max depth,
|
|
// then there's no need to check fs.Stats to know if it's a directory.
|
|
// If `options.deep` is a function, then we'll need fs.Stats
|
|
let maxDepthReached = dir.depth >= options.recurseDepth;
|
|
|
|
// Do we need to call `fs.stat`?
|
|
let needStats =
|
|
!maxDepthReached || // we need the fs.Stats to know if it's a directory
|
|
options.stats || // the user wants fs.Stats objects returned
|
|
options.recurseFn || // we need fs.Stats for the recurse function
|
|
options.filterFn || // we need fs.Stats for the filter function
|
|
EventEmitter.listenerCount(stream, 'file') || // we need the fs.Stats to know if it's a file
|
|
EventEmitter.listenerCount(stream, 'directory') || // we need the fs.Stats to know if it's a directory
|
|
EventEmitter.listenerCount(stream, 'symlink'); // we need the fs.Stats to know if it's a symlink
|
|
|
|
// If we don't need stats, then exit early
|
|
if (!needStats) {
|
|
if (this.filter(itemPath, posixPath)) {
|
|
this.pushOrBuffer({ data: itemPath });
|
|
}
|
|
return done();
|
|
}
|
|
|
|
// Get the fs.Stats object for this path
|
|
stat(options.facade.fs, fullPath, (err, stats) => {
|
|
if (err) {
|
|
// fs.stat threw an error
|
|
this.emit('error', err);
|
|
return done();
|
|
}
|
|
|
|
try {
|
|
// Add the item's path to the fs.Stats object
|
|
// The base of this path, and its separators are determined by the options
|
|
// (i.e. options.basePath and options.sep)
|
|
stats.path = itemPath;
|
|
|
|
// Add depth of the path to the fs.Stats object for use this in the filter function
|
|
stats.depth = dir.depth;
|
|
|
|
if (this.shouldRecurse(stats, posixPath, maxDepthReached)) {
|
|
// Add this subdirectory to the queue
|
|
this.queue.push({
|
|
path: fullPath,
|
|
basePath: itemPath + options.sep,
|
|
posixBasePath: posixPath + '/',
|
|
depth: dir.depth + 1,
|
|
});
|
|
}
|
|
|
|
// Determine whether this item matches the filter criteria
|
|
if (this.filter(stats, posixPath)) {
|
|
this.pushOrBuffer({
|
|
data: options.stats ? stats : itemPath,
|
|
file: stats.isFile(),
|
|
directory: stats.isDirectory(),
|
|
symlink: stats.isSymbolicLink(),
|
|
});
|
|
}
|
|
|
|
done();
|
|
}
|
|
catch (err2) {
|
|
// An error occurred while processing the item
|
|
// (probably during a user-specified function, such as options.deep, options.filter, etc.)
|
|
this.emit('error', err2);
|
|
done();
|
|
}
|
|
});
|
|
}
|
|
|
|
/**
|
|
* Pushes the given chunk of data to the stream, or adds it to the buffer,
|
|
* depending on the state of the stream.
|
|
*
|
|
* @param {object} chunk
|
|
*/
|
|
pushOrBuffer (chunk) {
|
|
// Add the chunk to the buffer
|
|
this.buffer.push(chunk);
|
|
|
|
// If we're still reading, then immediately emit the next chunk in the buffer
|
|
// (which may or may not be the chunk that we just added)
|
|
if (this.shouldRead) {
|
|
this.pushFromBuffer();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Immediately pushes the next chunk in the buffer to the reader's stream.
|
|
* The "data" event will always be fired (via {@link Readable#push}).
|
|
* In addition, the "file", "directory", and/or "symlink" events may be fired,
|
|
* depending on the type of properties of the chunk.
|
|
*/
|
|
pushFromBuffer () {
|
|
let stream = this.stream;
|
|
let chunk = this.buffer.shift();
|
|
|
|
// Stream the data
|
|
try {
|
|
this.shouldRead = stream.push(chunk.data);
|
|
}
|
|
catch (err) {
|
|
this.emit('error', err);
|
|
}
|
|
|
|
// Also emit specific events, based on the type of chunk
|
|
chunk.file && this.emit('file', chunk.data);
|
|
chunk.symlink && this.emit('symlink', chunk.data);
|
|
chunk.directory && this.emit('directory', chunk.data);
|
|
}
|
|
|
|
/**
|
|
* Determines whether the given directory meets the user-specified recursion criteria.
|
|
* If the user didn't specify recursion criteria, then this function will default to true.
|
|
*
|
|
* @param {fs.Stats} stats - The directory's {@link fs.Stats} object
|
|
* @param {string} posixPath - The item's POSIX path (used for glob matching)
|
|
* @param {boolean} maxDepthReached - Whether we've already crawled the user-specified depth
|
|
* @returns {boolean}
|
|
*/
|
|
shouldRecurse (stats, posixPath, maxDepthReached) {
|
|
let options = this.options;
|
|
|
|
if (maxDepthReached) {
|
|
// We've already crawled to the maximum depth. So no more recursion.
|
|
return false;
|
|
}
|
|
else if (!stats.isDirectory()) {
|
|
// It's not a directory. So don't try to crawl it.
|
|
return false;
|
|
}
|
|
else if (options.recurseGlob) {
|
|
// Glob patterns are always tested against the POSIX path, even on Windows
|
|
// https://github.com/isaacs/node-glob#windows
|
|
return options.recurseGlob.test(posixPath);
|
|
}
|
|
else if (options.recurseRegExp) {
|
|
// Regular expressions are tested against the normal path
|
|
// (based on the OS or options.sep)
|
|
return options.recurseRegExp.test(stats.path);
|
|
}
|
|
else if (options.recurseFn) {
|
|
try {
|
|
// Run the user-specified recursion criteria
|
|
return options.recurseFn.call(null, stats);
|
|
}
|
|
catch (err) {
|
|
// An error occurred in the user's code.
|
|
// In Sync and Async modes, this will return an error.
|
|
// In Streaming mode, we emit an "error" event, but continue processing
|
|
this.emit('error', err);
|
|
}
|
|
}
|
|
else {
|
|
// No recursion function was specified, and we're within the maximum depth.
|
|
// So crawl this directory.
|
|
return true;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Determines whether the given item meets the user-specified filter criteria.
|
|
* If the user didn't specify a filter, then this function will always return true.
|
|
*
|
|
* @param {string|fs.Stats} value - Either the item's path, or the item's {@link fs.Stats} object
|
|
* @param {string} posixPath - The item's POSIX path (used for glob matching)
|
|
* @returns {boolean}
|
|
*/
|
|
filter (value, posixPath) {
|
|
let options = this.options;
|
|
|
|
if (options.filterGlob) {
|
|
// Glob patterns are always tested against the POSIX path, even on Windows
|
|
// https://github.com/isaacs/node-glob#windows
|
|
return options.filterGlob.test(posixPath);
|
|
}
|
|
else if (options.filterRegExp) {
|
|
// Regular expressions are tested against the normal path
|
|
// (based on the OS or options.sep)
|
|
return options.filterRegExp.test(value.path || value);
|
|
}
|
|
else if (options.filterFn) {
|
|
try {
|
|
// Run the user-specified filter function
|
|
return options.filterFn.call(null, value);
|
|
}
|
|
catch (err) {
|
|
// An error occurred in the user's code.
|
|
// In Sync and Async modes, this will return an error.
|
|
// In Streaming mode, we emit an "error" event, but continue processing
|
|
this.emit('error', err);
|
|
}
|
|
}
|
|
else {
|
|
// No filter was specified, so match everything
|
|
return true;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Emits an event. If one of the event listeners throws an error,
|
|
* then an "error" event is emitted.
|
|
*
|
|
* @param {string} eventName
|
|
* @param {*} data
|
|
*/
|
|
emit (eventName, data) {
|
|
let stream = this.stream;
|
|
|
|
try {
|
|
stream.emit(eventName, data);
|
|
}
|
|
catch (err) {
|
|
if (eventName === 'error') {
|
|
// Don't recursively emit "error" events.
|
|
// If the first one fails, then just throw
|
|
throw err;
|
|
}
|
|
else {
|
|
stream.emit('error', err);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
module.exports = DirectoryReader;
|