##About Parson is a lighweight json library written in C.

##Features

• Full JSON support
• Lightweight (only 2 files)
• Simple API
• Addressing json values with dot notation (similiar 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.

voidprint_commits_info(constchar*username, constchar*repo) {
JSON_Value*root_value;
JSON_Array*commits;
JSON_Object*commit;
size_ti;
charcurl_command[512];
charcleanup_command[256];
charoutput_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.

voidpersistence_example(void) {
JSON_Value*schema=json_parse_string("{\"name\":\"\"}");
JSON_Value*user_data=json_parse_file("user_data.json");
charbuf[256];
constchar*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.

voidserialization_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 to the API, I won't merge it without prior discussion. Remember to follow parson's code style and write appropriate tests.

##License The MIT License (MIT)