gl-store-s3.js/node_modules/jmespath/README.md

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2019-05-08 10:43:08 +00:00
# jmespath.js
[![Build Status](https://travis-ci.org/jmespath/jmespath.js.png?branch=master)](https://travis-ci.org/jmespath/jmespath.js)
jmespath.js is a javascript implementation of JMESPath,
which is a query language for JSON. It will take a JSON
document and transform it into another JSON document
through a JMESPath expression.
Using jmespath.js is really easy. There's a single function
you use, `jmespath.search`:
```
> var jmespath = require('jmespath');
> jmespath.search({foo: {bar: {baz: [0, 1, 2, 3, 4]}}}, "foo.bar.baz[2]")
2
```
In the example we gave the ``search`` function input data of
`{foo: {bar: {baz: [0, 1, 2, 3, 4]}}}` as well as the JMESPath
expression `foo.bar.baz[2]`, and the `search` function evaluated
the expression against the input data to produce the result ``2``.
The JMESPath language can do a lot more than select an element
from a list. Here are a few more examples:
```
> jmespath.search({foo: {bar: {baz: [0, 1, 2, 3, 4]}}}, "foo.bar")
{ baz: [ 0, 1, 2, 3, 4 ] }
> jmespath.search({"foo": [{"first": "a", "last": "b"},
{"first": "c", "last": "d"}]},
"foo[*].first")
[ 'a', 'c' ]
> jmespath.search({"foo": [{"age": 20}, {"age": 25},
{"age": 30}, {"age": 35},
{"age": 40}]},
"foo[?age > `30`]")
[ { age: 35 }, { age: 40 } ]
```
## More Resources
The example above only show a small amount of what
a JMESPath expression can do. If you want to take a
tour of the language, the *best* place to go is the
[JMESPath Tutorial](http://jmespath.org/tutorial.html).
One of the best things about JMESPath is that it is
implemented in many different programming languages including
python, ruby, php, lua, etc. To see a complete list of libraries,
check out the [JMESPath libraries page](http://jmespath.org/libraries.html).
And finally, the full JMESPath specification can be found
on the [JMESPath site](http://jmespath.org/specification.html).