JsonRocket

Json Rocket is a fast JSON parser with the goal to extract pieces of information from a JSON message. It is not a fully fledged deserializer that reads JSON into DTO classes.

The goals of this project are:

• ultra fast parsing of a JSON data
• no heap allocations while parsing
• find/extract multiple values from a JSON message with at most one full tokenization

However, non-goals are:

• proper JSON validation: the code takes a lot of shortcuts for faster parsing that can potentially read invalid JSON. It is guaranteed thought that malformed JSON will not cause any Exceptions.

Installation

PM> Install-Package JsonRocket

Tokenization

The following JSON snippet can be tokenized like this

{
  "Id": 1,
  "Name": "Joh Doe",
  "Address": {
    "Street": "1st Avenue",
    "City": "Springfield"
  }
}

var json = Encoding.UTF8.GetBytes(""); // insert above snippet here
var tokenizer = new JsonRocket.Tokenizer();
tokenizer.Reset(json);
while (tokenizer.MoveNext())
{
  Console.WriteLine(tokenizer.Current);
}

the output will be

ObjectStart
Key
Integer
Key
String
Key
ObjectStart
Key
String
Key
String
ObjectEnd
ObjectEnd

Value Extraction

The following snippet extracts the Name (John Doe) and the City (Springfield) from the JSON. This happens with a single iteration through the tokenizer.

var trie = new JsonRocket.Trie();
trie.Add("Name");
trie.Add("Address.City");
var extractor = new JsonRocket.Extractor(trie);

var json = Encoding.UTF8.GetBytes(""); // insert above snippet here
var tokenizer = new JsonRocket.Tokenizer();
tokenizer.Reset(json);

var result = new List<JsonRocket.ExtractedValue>();
extractor.ReadFrom(tokenizer, result);
Console.WriteLine(result[0].Value.ReadString()); // prints 'John Doe'
Console.WriteLine(result[1].Value.ReadString()); // prints 'Springfield'