gulp-data
Learn more about gulp.js, the streaming build system
Introduction
Gulp-data proposes a common API for attaching data to the file object for other plugins to consume. With gulp-data you can generate a data object from a variety of sources: json, front-matter, database, anything... and set it to the file object for other plugins to consume.
Many plugins, such as gulp-swig
or gulp-jade
allow for JSON data to be passed via their respective options parameter. However, frequently what you want is the ability to dynamically set the data based off the file name or some other attribute of the file. Without using another plugin, this becomes problematic - as the number of ways of getting at data (via JSON files, front-matter, data bases, promises, etc) increases, the more plugin authors have to update their APIs to support these sources. The gulp-data
plugin aims to standardize a method that is generic enough to encapsulate these data sources into a single data
property attached to the file object. It's really up to you as to where your data comes from, a JSON file, from a front-matter section of the file, or even a database, gulp-data
doesn't really care.
However, for this to be effective, I'm asking plugin devs that receive data through the options parameter to make a small change to additionally accept this data through the file.data
property. (See below)
Important Update
Thanks to the help of @izaakschroeder we've reached version 1.0 (now 1.0.1). Some important changes have been added, primarily support for promises, and error handling. The examples below have been updated to reflect these changes.
Usage
First, install gulp-data
as a development dependency:
npm install --save-dev gulp-data
Then, add it to your gulpfile.js
:
var gulp = ;var swig = ;var data = ;var fm = ;var path = ;var MongoClient = MongoClient;var fs = ; /* Get data via JSON file, keyed on filename.*/gulp; /* Get data via front matter*/gulp; /* Get data via database, keyed on filename.*/gulp;
API
data(dataFunction)
dataFunction
Type: Function
Define a function that returns a data object via a callback function. Could return JSON from a file, or an object returned from a database.
You can return the data object:
You can return a promise:
You can feed a result object through the callback:
You can feed a promise object through the callback:
You can throw an error:
You can raise an error via the callback:
Note to gulp plugin authors
If your plugin needs a data object, one that normally gets passed in via your options parameter, I'm asking if you could please update the plugin to accept data from the file.data
property. Here's how you can do it:
gulp-swig
usually accepts data via its options.data
parameter, but with a small change, it checks to see if there's a file.data
property and if so, merges it into the data object.
var data = opts.data || {};
if (file.data) {
data = _.extend(file.data, data);
// or just data = file.data if you don't care to merge. Up to you.
}