read-vinyl-file-stream v2.0.3
read vinyl file stream
Turns out that reading all the files in a vinyl stream is cumbersome, and supporting all of the options is a little bit annoying. I decided that I don't want to write that code more than once. So here is a library that does that. This is most useful for gulp plugins that need to transform all the files in a stream, though I am sure you can figure out other ways to use it too.
Install
npm install read-vinyl-file-stream
API
read-vinyl-file-stream(iterator {Function} , flush {Function})
The module is a function that creates a transform stream. It will read the vinyl file, whether it is a buffer or a stream internally. It takes the following parameters, in order:
- iterator {Function} Required - the method that will process the files.
- flush {Function} Optional - the method to call before the stream ends.
- encoding {String} Optional - the encoding to use for the content provided to the iterator function. By default, this is a UTF-8 string. The following options are supported:
'utf8'
- provide the content in a UTF-8 string.'buffer'
- provide the content in a raw buffer. This is useful if you are processing binary files, for example.
iterator(content, file, stream, cb)
The function that you provide to it has the following parameters, in order:
- content - the content of the file.
- file - the vinyl file itself.
- stream - the transform stream that is being iterated.
- cb - a callback to call once you are done processing the file. You must call this in order for the stream to continue.
flush(stream, cb)
This is a function that will allow you to execute some code after all the files have been read but before the stream ends. It has the following parameters, in order:
- stream - the transform stream that is being iterated.
- cb - a callback to call once you are done with the flush actions. You must call this in order for the stream to end.
Examples
Observe all of the files:
var readFiles = require('read-vinyl-file-stream');
var input = getVinylStream();
var hashOfFiles = {};
input.pipe(readFiles(function (content, file, stream, cb) {
hashOfFiles[file.path] = content;
cb();
}));
Transform the content of the file and output it back to the stream:
var readFiles = require('read-vinyl-file-stream');
var input = getVinylStream();
input.pipe(readFiles(function (content, file, stream, cb) {
var newContent = doWorkToTheContent(content);
cb(null, newContent);
}));
Split the file into multiple files and output all of them to the stream:
var readFiles = require('read-vinyl-file-stream');
var File = require('vinyl');
var input = getVinylStream();
input.pipe(readFiles(function (content, file, stream, cb) {
var lines = content.split('\n');
lines.forEach(function (line, idx) {
stream.push(new File({
contents: new Buffer(line),
path: file.path + 'line' + idx
}));
});
cb();
}));
Use inside gulp
(to create a filter):
var gulp = require('gulp');
var readFiles = require('read-vinyl-file-stream');
gulp.task('mytask', function() {
return gulp.src('*.ext')
.pipe(readFiles(function (content, file, stream, cb) {
if (/^n/.test(content)) {
return cb(null, content);
}
cb();
}))
.pipe(gulp.dest('filesThatStartWithN'));
});