yourslab/coreJSON

coreJSON Library

A parser strictly enforcing the ECMA-404 JSON standard, suitable for microcontrollers

Reference example

#include <stdio.h>
#include "core_json.h"

int main()
{
    // Variables used in this example.
    JSONStatus_t result;
    char buffer[] = "{\"foo\":\"abc\",\"bar\":{\"foo\":\"xyz\"}}";
    size_t bufferLength = sizeof( buffer ) - 1;
    char queryKey[] = "bar.foo";
    size_t queryKeyLength = sizeof( queryKey ) - 1;
    char * value;
    size_t valueLength;
    
    // Calling JSON_Validate() is not necessary if the document is guaranteed to be valid.
    result = JSON_Validate( buffer, bufferLength );
    
    if( result == JSONSuccess )
    {
        result = JSON_Search( buffer, bufferLength, queryKey, queryKeyLength, '.',
                              &value, &valueLength );
    }
    
    if( result == JSONSuccess )
    {
        // The pointer "value" will point to a location in the "buffer".
        char save = value[ valueLength ];
        // After saving the character, set it to a null byte for printing.
        value[ valueLength ] = '\0';
        // "Found: bar.foo -> xyz" will be printed.
        printf( "Found: %s -> %s\n", queryKey, value );
        // Restore the original character.
        value[ valueLength ] = save;
    }

    return 0;
}

A search may descend through nested objects when the queryKey contains matching key strings joined by a separator (e.g. .). In the example above, bar has the value {"foo":"xyz"}. Therefore, a search for query key bar.foo would output xyz.

Building coreJSON

A compiler that supports C89 or later such as gcc is required to build the library.

For instance, if the example above is copied to a file named example.c, gcc can be used like so:

gcc -I source/include example.c source/core_json.c -o example
./example

gcc can also produce an output file to be linked:

gcc -I source/include -c source/core_json.c

Generating documentation

The Doxygen references were created using Doxygen version 1.8.20. To generate the Doxygen pages, please run the following command from the root of this repository:

doxygen docs/doxygen/config.doxyfile

Building unit tests

Platform Prerequisites

For running unit tests
- C90 compiler like gcc
- CMake 3.13.0 or later
- Ruby 2.0.0 or later is additionally required for the CMock test framework (that we use).
For running the coverage target, gcov is additionally required.

Steps to build Unit Tests

Go to the root directory of this repository.
Create build directory: mkdir build && cd build
Run cmake while inside build directory: cmake -S ../test
Run this command to build the library and unit tests: make all
The generated test executables will be present in build/bin/tests folder.
Run ctest to execute all tests and view the test run summary.

yourslab / coreJSON