supermetrics/jsonpath

Extract data from a decoded JSON document using the versatile JSONPath query language

dev-main 2024-09-27 09:33 UTC

This package is auto-updated.

Last update: 2024-10-28 22:39:55 UTC


README

Build status Code coverage

JSONPath is a language for querying and extracting data from JSON, similar to XPath for XML.

This PHP extension for JSONPath is inspired by Stefan Goessner's original implementation and is intended to be a fast(er) replacement for JSONPath libraries written in PHP.

Intended audience

This extension is ideal for projects that depend heavily on JSONPath and could benefit from a native C implementation. Other JSONPath implementations often rely on eval() and regular expressions, while JsonPath-PHP is a more efficient lexer/parser. Extracting the data in C rather than in PHP results in great performance. In fact, JsonPath-PHP is often faster than manually traversing the array in PHP and picking the matching element(s).

The tradeoff for increased performance is the overhead of adding this extension to your PHP installation. If you're running your PHP application in a shared environment where you can't install PHP extensions, we recommend checking out more convenient PHP implementations like this, this, and this. Or switching to an environment that you have more control over. 😉

Installation

Linux and macOS

Option 1: Build using PECL

$ pecl install jsonpath

For more instructions on how to use PECL, see the PECL documentation.

Option 2: Build manually

Clone this repository to the directory of your choice, then run:

$ phpize
$ ./configure --enable-jsonpath
$ make
$ TEST_PHP_ARGS="-q" make test
$ sudo make install

Enable the extension

$ sudo touch /etc/php.d/jsonpath.ini
$ echo "extension=jsonpath.so" | sudo tee /etc/php.d/jsonpath.ini
$ php -m | grep jsonpath

If you're running PHP with the PHP-FPM service, restart it for the changes to take effect:

$ sudo service php-fpm restart

Windows

For pre-built Windows DLLs, see the PHP Extensions Repository.

Remember to add extension=jsonpath to your php.ini in order to enable the extension.

For more instructions on installing PHP extensions, see the PECL documentation.

Usage

<?php

use JsonPath\JsonPath;
use JsonPath\JsonPathException;

$jsonPath = new JsonPath();

try {
    // Query a data array using a JSONPath expression string.
    // Returns an array of matching elements, or false if nothing was found.
    $result = $jsonPath->find($data, $selector);
} catch (JsonPathException $exception) {
    echo $exception->getMessage(); // Usually a syntax error in the selector
}

Examples

<?php

$json = <<<JSON
{ "store": {
    "book": [ 
      { "category": "reference",
        "author": "Nigel Rees",
        "title": "Sayings of the Century",
        "price": 8.95
      },
      { "category": "fiction",
        "author": "Evelyn Waugh",
        "title": "Sword of Honour",
        "price": 12.99
      },
      { "category": "fiction",
        "author": "Herman Melville",
        "title": "Moby Dick",
        "isbn": "0-553-21311-3",
        "price": 8.99
      },
      { "category": "fiction",
        "author": "J. R. R. Tolkien",
        "title": "The Lord of the Rings",
        "isbn": "0-395-19395-8",
        "price": 22.99
      }
    ],
    "bicycle": {
      "color": "red",
      "price": 19.95
    }
  }
}
JSON;

$data = json_decode($json, true);

$jsonPath = new \JsonPath\JsonPath();

echo "Example 1: - The authors of all books in the store: \n";
echo json_encode($jsonPath->find($data, "$.store.book[*].author"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    "Nigel Rees",
    "Evelyn Waugh",
    "Herman Melville",
    "J. R. R. Tolkien"
]
*/

echo "Example 2 - All authors:\n";
echo json_encode($jsonPath->find($data, "$..author"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    "Nigel Rees",
    "Evelyn Waugh",
    "Herman Melville",
    "J. R. R. Tolkien"
]
*/

echo "Example 3 - All things in the store:\n";
echo json_encode($jsonPath->find($data, "$.store.*"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    [
        {
            "category": "reference",
            "author": "Nigel Rees",
            "title": "Sayings of the Century",
            "price": 8.95
        },
        {
            "category": "fiction",
            "author": "Evelyn Waugh",
            "title": "Sword of Honour",
            "price": 12.99
        },
        {
            "category": "fiction",
            "author": "Herman Melville",
            "title": "Moby Dick",
            "isbn": "0-553-21311-3",
            "price": 8.99
        },
        {
            "category": "fiction",
            "author": "J. R. R. Tolkien",
            "title": "The Lord of the Rings",
            "isbn": "0-395-19395-8",
            "price": 22.99
        }
    ],
    {
        "color": "red",
        "price": 19.95
    }
]
*/

echo "Example 4 - The price of everything in the store:\n";
echo json_encode($jsonPath->find($data, "$.store..price"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    8.95,
    12.99,
    8.99,
    22.99,
    19.95
]
*/

echo "Example 5 - The third book:\n";
echo json_encode($jsonPath->find($data, "$..book[2]"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    {
        "category": "fiction",
        "author": "Herman Melville",
        "title": "Moby Dick",
        "isbn": "0-553-21311-3",
        "price": 8.99
    }
]
*/

echo "Example 6 - The title of the last book:\n";
echo json_encode($jsonPath->find($data, "$..book[-1].title"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    "The Lord of the Rings"
]
*/

echo "Example 7 - Lookup by ISBN:\n";
echo json_encode($jsonPath->find($data, "$.store.book[?(@.isbn == '0-395-19395-8')]"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    {
        "category": "fiction",
        "author": "J. R. R. Tolkien",
        "title": "The Lord of the Rings",
        "isbn": "0-395-19395-8",
        "price": 22.99
    }
]
*/

echo "Example 8 - Lookup by category and price:\n";
echo json_encode($jsonPath->find($data, "$.store.book[?(@.category == 'fiction' && @.price <= 15.00)]"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    {
        "category": "fiction",
        "author": "Evelyn Waugh",
        "title": "Sword of Honour",
        "price": 12.99
    },
    {
        "category": "fiction",
        "author": "Herman Melville",
        "title": "Moby Dick",
        "isbn": "0-553-21311-3",
        "price": 8.99
    }
]
*/

echo "Example 9 - Lookup by author using regular expression:\n";
echo json_encode($jsonPath->find($data, "$.store.book[?(@.author =~ /Tolkien$/)]"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    {
        "category": "fiction",
        "author": "J. R. R. Tolkien",
        "title": "The Lord of the Rings",
        "isbn": "0-395-19395-8",
        "price": 22.99
    }
]
*/

echo "Example 10 - The titles of books without an ISBN:\n";
echo json_encode($jsonPath->find($data, "$.store.book[?(!@.isbn)].title"), JSON_PRETTY_PRINT);
echo "\n\n";
/*
[
    "Sayings of the Century",
    "Sword of Honour"
]
*/

JSONPath expression syntax

Also see the examples.

Performance benchmarks

Chart showing a performance comparison between JsonPath-PHP, native PHP (JsonPath-PHP sometimes faster, sometimes slower), and the fastest tested PHP library (JsonPath-PHP always faster)

The numbers in the chart were obtained when running the benchmark suite in PHP 8.1 with OPcache and JIT enabled.

If you want to run benchmarks yourself, have a look at the jsonpath-benchmark repo.

License

JsonPath-PHP is open-sourced software licensed under the PHP License 3.01.

Tests

The unit tests utilize PHP's core and extension testing framework. The recommended way to run the tests is:

$ TEST_PHP_ARGS="-q" make test

JsonPath-PHP implements the JSONPath Comparison test suite. These tests reside in the tests/comparison_* directories.

To generate a code coverage report, install lcov and build the extension with the special --enable-code-coverage flag, before running the tests and processing the code coverage output:

$ ./configure --enable-jsonpath --enable-code-coverage
$ make clean
$ TEST_PHP_ARGS="-q" make test
$ make lcov

You can then find a coverage report in the lcov_html/ directory.

Code Quality Tooling

Please run the code formatter and linter (and fix any issues reported by the linter) before filing a pull request.

You may check the code format and linter automatically before committing by setting up a pre-commit hook:

make setup-pre-commit

Formatting

Code formatting requires clang-format.

make format-code

Linting

Linting requires cppcheck.

make lint-code

Contributors

JsonPath-PHP is created by Mike Kaminski and maintained by Supermetrics and Mike Kaminski.

Found a bug, or missing some feature? Raise an issue or submit a pull request.