Awesome
grunt-update-json
Merge parts from one or more JSON files together. I use grunt-update-json
to keep my bower.json
and component.json
in sync with package.json
.
Upgrading from 1.x
The semantics of Object Groupings have been reversed:
- was
{from: "to"}
- now``{to: "from"}`
Getting Started
npm install grunt-update-json --save-dev
I highly favor using the fabulous load-grunt-tasks
over the tiring and cumbersome grunt.loadNpmTasks
. Your grunt tasks are all in your package.json
, so let's embrace DRY:
npm install load-grunt-tasks --save-dev
// Gruntfile.js
module.exports = function (grunt) {
require('load-grunt-tasks')(grunt); // load all grunt tasks. Done!
Using the update_json
task
In your awesome project's Gruntfile, add a section named update_json
:
// Gruntfile.js
grunt.initConfig({
update_json: {
// set some task-level options
options: {
src: 'package.json',
indent: '\t'
},
// update bower.json with data from package.json
bower: {
src: 'package.json', // where to read from
dest: 'bower.json', // where to write to
// the fields to update, as a String Grouping
fields: 'name version description repository'
},
// update component.json with data from package.json
// component.json fields are a named a bit differently from
// package.json, so let's tell update_json how to map names
component: {
// reuse the task-level `src`
dest: 'component.json', // where to write to
fields: { // the fields to update
// notice how this time we're passing a hash instead
// of an array; this allows us to map the field names.
// We still specify all the names we want, and additionally
// we also specify the target name in the detination file.
// to from
// ----------- -------------------
'name' : null, // null means 'leave as is'
'description' : 'description',// but feel free to type the field name twice
'repository' : 'repo', // rename 'repository' to 'repo'
'version' : null,
'keywords' : null,
'main' : null,
'dependencies' : null,
'development' : 'devDependencies',
'license' : null,
}
},
// `composer` has the same data as `package`, but has some tricky
// semantics
composer: {
// again, reuse the task-level `src`
dest: 'composer.json',
// the fields in an Array Grouping with some embedded Object Groupings
fields: [
{
name: function(src){
return src.repository.url.match(/([^\/]+\/[^\/]+).git/)[1];
}
},
'description',
'keywords',
'homepage',
{
license: 'licenses/0/type',
authors: [{
name: 'author/name',
homepage: 'author/url'
}]
}
]
}
}
});
API
options
Like most Grunt tasks, options can be specified at the update_json
level
and/or at the update_json:<target>
level. Target-level options
override task-level options
.
options.indent
By default, output will not be pretty-printed. Specify a value here to have indentation applied:
update_json: {options: {indent: "\t"}}
or for spaces:
update_json: {options: {indent: " "}}
Source Data
src
An input JSON file. May be a list, which will be [
_.merge
d][_merge] together. [_merge]: http://lodash.com/docs#merge
Destination Data
dest
An output JSON file.
Field Groupings
fields
an ordered collection of field specifications, which can optionally contain additional lists of fields.
Object Grouping
{fields: {field: null, another: "yetanother"}}
A list of field specs, pointing at any other kind of field specification.
Array Grouping
{fields: ["field", "another", "still another > yet another"]}
Create field copies, or field renames, of each of the listed fields.
String Grouping
{fields: "field, another, still another > yetanother"}
Create field copies, or field renames, of each of the listed fields.
The most concise way to copy/rename a number of fields of simple JSON documents
Limitations
- Can't handle fields with
,
or>
in their names. - Can't handle most complex field paths.
Field Specifications
The canonical Object Grouping format is used here: some specifications are not compatible with some Groupings.
Field Copy
{field: null}
Create or replace
field
indest
from the value offield
insrc
.
Field Rename
{renamed: "original"}
or"original > renamed"
String Grouping onlyCreate or replace
renamed
indest
with the value oforiginal
fromsrc
.
Field Pointer
{field: "/some/deep/field"}
Create or replace
field
indest
fromsome/deep/field
insrc
.
A field spec destination which starts with /
will be interepreted as a
json-pointer.
To select a field that begins with a literal /
, escape with a single \
(written \\
):
{field: "\\/a"}
Field Path
{field: "$.some.path[(@.with='filters')]"}
Create or replace
field
indest
with the value of nodes found with a JSONPath query
A field spec destination which starts with $.
will be interpreted as a
JSONPath selector.
To select a field that begins with a literal $.
, escape with a single \
(written \\
):
{field: "\\$.a"}
Field Collapse
{field: ["first", "second"]}
Create or replace an array named
field
indest
with the values offirst
andsecond
fromsrc
.
Field Construct
{field: {first: "first", second: "second"}}
Create or merge an object
field
indest
with labeledfirst
andsecond
with their respective values fromsrc
Field Function
{field: function(src){ return src.field; }}
Create a field named
field
that is the output of running a function againstsrc
.
If all else fails, you can supply a function which will called with a copy of the combined source object.
update_json: {
composer: {
src: "package.json",
dest: "composer.json",
fields: {
name: function(src){
// pull username/repo off a github url
return src.repository.url.match(/([^\/]+\/[^\/]+).git/)[1];
}
}
}
}
Ideas for improvement
- see enhancements
License
MIT