You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
Krzysztof Gabis ba29f4eda9 1.5.3: Fixes compilation on mac os (due to sprintf being deprecated) #209 7 months ago
.github Adds sponsor button 1 year ago
tests 1.4.0: Accepting trailing commas in objects and arrays 2 years ago
.gitignore 1.3.1: Fixes size_t conversion on x64 systems. Excluding build/ in .gitignore. (#177) 2 years ago
CMakeLists.txt 1.5.3: Fixes compilation on mac os (due to sprintf being deprecated) #209 7 months ago
LICENSE Updates license (version and year). 2 years ago
Makefile 1.5.3: Fixes compilation on mac os (due to sprintf being deprecated) #209 7 months ago
README.md Update README.md 3 years ago
meson.build 1.5.3: Fixes compilation on mac os (due to sprintf being deprecated) #209 7 months ago
package.json 1.5.3: Fixes compilation on mac os (due to sprintf being deprecated) #209 7 months ago
parson.c 1.5.3: Fixes compilation on mac os (due to sprintf being deprecated) #209 7 months ago
parson.h 1.5.3: Fixes compilation on mac os (due to sprintf being deprecated) #209 7 months ago
tests.c 1.5.3: Fixes compilation on mac os (due to sprintf being deprecated) #209 7 months ago

README.md

About

Parson is a lightweight json library written in C.

Features

  • Lightweight (only 2 files)
  • Simple API
  • Addressing json values with dot notation (similar to C structs or objects in most OO languages, e.g. "objectA.objectB.value")
  • C89 compatible
  • Test suites

Installation

Run:

git clone https://github.com/kgabis/parson.git

and copy parson.h and parson.c to you source code tree.

Run make test to compile and run tests.

Examples

Parsing JSON

Here is a function, which prints basic commit info (date, sha and author) from a github repository.

void print_commits_info(const char *username, const char *repo) {
    JSON_Value *root_value;
    JSON_Array *commits;
    JSON_Object *commit;
    size_t i;
    
    char curl_command[512];
    char cleanup_command[256];
    char output_filename[] = "commits.json";
    
    /* it ain't pretty, but it's not a libcurl tutorial */
    sprintf(curl_command, 
        "curl -s \"https://api.github.com/repos/%s/%s/commits\" > %s",
        username, repo, output_filename);
    sprintf(cleanup_command, "rm -f %s", output_filename);
    system(curl_command);
    
    /* parsing json and validating output */
    root_value = json_parse_file(output_filename);
    if (json_value_get_type(root_value) != JSONArray) {
        system(cleanup_command);
        return;
    }
    
    /* getting array from root value and printing commit info */
    commits = json_value_get_array(root_value);
    printf("%-10.10s %-10.10s %s\n", "Date", "SHA", "Author");
    for (i = 0; i < json_array_get_count(commits); i++) {
        commit = json_array_get_object(commits, i);
        printf("%.10s %.10s %s\n",
               json_object_dotget_string(commit, "commit.author.date"),
               json_object_get_string(commit, "sha"),
               json_object_dotget_string(commit, "commit.author.name"));
    }
    
    /* cleanup code */
    json_value_free(root_value);
    system(cleanup_command);
}

Calling print_commits_info("torvalds", "linux"); prints:

Date       SHA        Author
2012-10-15 dd8e8c4a2c David Rientjes
2012-10-15 3ce9e53e78 Michal Marek
2012-10-14 29bb4cc5e0 Randy Dunlap
2012-10-15 325adeb55e Ralf Baechle
2012-10-14 68687c842c Russell King
2012-10-14 ddffeb8c4d Linus Torvalds
...

Persistence

In this example I'm using parson to save user information to a file and then load it and validate later.

void persistence_example(void) {
    JSON_Value *schema = json_parse_string("{\"name\":\"\"}");
    JSON_Value *user_data = json_parse_file("user_data.json");
    char buf[256];
    const char *name = NULL;
    if (user_data == NULL || json_validate(schema, user_data) != JSONSuccess) {
        puts("Enter your name:");
        scanf("%s", buf);
        user_data = json_value_init_object();
        json_object_set_string(json_object(user_data), "name", buf);
        json_serialize_to_file(user_data, "user_data.json");
    }
    name = json_object_get_string(json_object(user_data), "name");
    printf("Hello, %s.", name);
    json_value_free(schema);
    json_value_free(user_data);
    return;
}

Serialization

Creating JSON values is very simple thanks to the dot notation. Object hierarchy is automatically created when addressing specific fields. In the following example I create a simple JSON value containing basic information about a person.

void serialization_example(void) {
    JSON_Value *root_value = json_value_init_object();
    JSON_Object *root_object = json_value_get_object(root_value);
    char *serialized_string = NULL;
    json_object_set_string(root_object, "name", "John Smith");
    json_object_set_number(root_object, "age", 25);
    json_object_dotset_string(root_object, "address.city", "Cupertino");
    json_object_dotset_value(root_object, "contact.emails", json_parse_string("[\"email@example.com\",\"email2@example.com\"]"));
    serialized_string = json_serialize_to_string_pretty(root_value);
    puts(serialized_string);
    json_free_serialized_string(serialized_string);
    json_value_free(root_value);
}

Output:

{
    "name": "John Smith",
    "age": 25,
    "address": {
        "city": "Cupertino"
    },
    "contact": {
        "emails": [
            "email@example.com",
            "email2@example.com"
        ]
    }
}

Contributing

I will always merge working bug fixes. However, if you want to add something new to the API, please create an "issue" on github for this first so we can discuss if it should end up in the library before you start implementing it. Remember to follow parson's code style and write appropriate tests.

My other projects

  • ape - simple programming language implemented in C library
  • kgflags - easy to use command-line flag parsing library
  • agnes - header-only NES emulation library

License

The MIT License (MIT)