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jsonb is a binary formatJSON representation inspired byPostgreSQL andCockroachDB. It provides a fast, lightweight and easy-to-use API for working withJSON data.

• Good compatibility:jsonb fully supports theJSON standard and can be used to store complex data structures.
• Fast performance:jsonb is designed for high performance, allowing you to work with largeJSON data sets with ease.
• Easy to use:jsonb provides a number of built-in functions to support various operations, and also supports theJSONPath syntax for selecting and extracting subset elements.
• Safe and secure:jsonb is written in Rust, which provides memory and thread safety guarantees, making it a safe choice for handling sensitive data.

Thejsonb encoding format is a tree-like structure. Each node contains a container header, a number of JEntry headers, and nested encoding values.

• 32-bit container header. 3 bits identify the type of value, includingscalar,object andarray, and 29 bits identify the number of JEntries in thearray orobject. The root node of thejsonb value is always a container header.
  • scalar container header:0x20000000
  • object container header:0x40000000
  • array container header:0x80000000
• 32-bit JEntry header. 1 bit identifies whether the JEntry stores a length or an offset, 3 bits identify the type of value, includingnull,string,number,false,true andcontainer, and the remaining 28 bits identify the length or offset of the encoding value.
  • null JEntry header:0x00000000
  • string JEntry header:0x10000000
  • number JEntry header:0x20000000
  • false JEntry header:0x30000000
  • true JEntry header:0x40000000
  • container JEntry header0x50000000
• Encoding value. Different types of JEntry header have different encoding values.
  • null,true,false: no encoding value, identified by the JEntry header.
  • string: a normal UTF-8 string.
  • number: an encoded number to represent uint64s, int64s and float64s.
  • container: a nestedjson value with a recursive structure.

// JSON value[false, 10, {"k":"v"}]// JSONB encoding0x80000003    array container header (3 JEntries)0x30000000    false JEntry header (no encoding value)0x20000002    number JEntry header (encoding value length 2)0x5000000e    container JEntry header (encoding value length 14)0x500a        number encoding value (10)0x40000001    object container header (1 JEntry)0x10000001    string key JEntry header (encoding value length 1)0x10000001    string value JEntry header (encoding value length 1)0x6b          string encoding value ("k")0x76          string encoding value ("v")

Thejsonb value is an enumeration that represents all kinds ofJSON values and serves as an intermediate for converting other data types to thejsonb binary format value.

// jsonb value#[derive(Clone,PartialEq,Eq)]pubenumValue<'a>{Null,Bool(bool),String(Cow<'a,str>),Number(Number),Array(Vec<Value<'a>>),Object(Object<'a>),}

jsonb implements a number of commonly used built-in functions. Since most functions only focus on a subset of the total value, using container headers and JEntry headers to can efficiently skip over intermediate parts of thejsonb value. This avoids time-consuming deserialisation operations and provides very high performance. For more information, seehttps://docs.rs/jsonb/latest/jsonb/#functions

SQL/JSONPath is a query language used to select and extract a subset of elements from ajsonb value.

The following operators have been implemented:

fnmain(){let json =r#"        {            "name":"Fred",            "phones":[                {                    "type":"home",                    "number":3720453                },                {                    "type": "work",                    "number":5062051                }            ]        }"#;let path =r#"$.phones[*]?(@.number == 3720453)"#;// parse JSON string to jsonb valuelet value = jsonb::parse_value(json.as_bytes()).unwrap();// encode jsonb value to jsonb binary valuelet jsonb = value.to_vec();// parse JSONPath stringlet json_path = jsonb::jsonpath::parse_json_path(path.as_bytes()).unwrap();// select subset value from jsonb binary valueletmut sub_jsonb =Vec::new();letmut sub_offsets =Vec::new();    jsonb::get_by_path(&jsonb, json_path,&mut sub_jsonb,&mut sub_offsets);// value={"number":3720453,"type":"home"}println!("value={}", jsonb::to_string(&sub_jsonb));}

jsonb is an open source project and all kinds of contributions are welcome! You can help with ideas, code or documentation.

Licensed under theApache License, Version 2.0