praveenmunagapati/ubjsoncpp

A high performance C++14 library for effortlessly reading and writing UBJSON

UbjsonCpp

A high performance C++14 library for effortlessly reading and writing UBJSON

This library implements UBJSON Draft 12 and Value semmantics

About

Please see UBJSON Official Website

About This Library

UjsonCpp is a UBJSON Library that enables a client to seamlessly stream In/Out UBJ encoded data from a StreamSource. The StreamSource is a template type that can be substituted provided it meets the Concept requirements. For example, std::ostream, std::istream and Boost.Asio can seamless be plugged in.

This library has been implemented using C++14, as part of the timl (Timothy's Libraries) for public use.

The Value type is an intuitive union type that is used to hold any UBJSON type, which includes int, char, strings, floats, binary, etc. See documentation for details

Usage Snippet

using namespace ubjson;
Value v1, v2;

v1 = 34535;     //Assign to integral types
v1 = "I so much love C++14";    //std::string constructable
v2 = v1;

std::string s1 = std::move(v1); //move string
//very viable for large amounts of strings


auto b = static_cast<std::string>(v2)   //safely cast to std::string or throw;
v2 = -2342.2525236;

std::string s2 = v2.asString();   //Value::asString() exception safe unconditional cast
std::cout << v2.asInt() << std::endl;   //unconditionally cast to int (noexcept)....

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Modifiying Values in place? ...Yes

using namespace ubjson;
Value val = "Are we there yet Mr. Donald Knuth?";
std::string& ref1 = val;
auto& ref2 = static_cast<std::string&>(val);

//To lower
ref1[0] = std::tolower(ref2[0]);

auto boool = (ref1 == ref2) and (ref1 == val); //Will be true

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Key-Value pairs or Maps? ...perfect

using namespace ubjson;
Value m1("country", "Nigeria");
Value m2;
m2["country"] = "Nigeria";
m2["location"]["latitude"]["relative"] = 34.2523; //creates the maps on the fly... fast

m1 == m2;   //Compare an Value type;

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Arrays? ...No problems

using namespace ubjson;
Value array = {"Timothy", 2015, -34253535.235235, '@', Value("country", "Nigeria")};
array.push_back("Amazing Array");

for(auto val : array)
  std::cout << val.asString() << std::endl;

if(array.contains(2015))
  array.remove(2015)

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Value also has binary types:

using namespace ubjson;
using Binary = Value::BinaryType;   //Actually, an alias for std::vector<unsigned char>
Value binary = Binary({0xF3, 0x33, 0x76, 0xAA, 0x23});

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Stream Operations

Reading from a Stream is very simple.

  std::ifstream input;
  input.open("sample1.ubj", ios::binary);

  StreamReader<decltype(input)> reader(input);
  Value val = reader.getNextValue();

  //or
  StreamReader<std::ifstream> reader(input); ///your choice :-)

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Writing to a Stream is likewise very simple.

  Value planet;
  planet["name"] = "Earth";
  planet["position"] = 3;

  std::ofstream output;
  output.open("sample2.ubj", ios::binary);

  StreamWriter<std::ostream> writer(output);
  auto result = writer.writeValue(planet);

  if(result.second)
    std::cout << "Successfully wrote: " << result.first << " bytes" << std::endl;

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Pretty Printing.... easy (always outputs a valid json document):

Value value;
value["name"] = "Timothy"
value["country"] = "Nigeria";
value["favorites"] = { 34.351, -253, '@', value["country"], 34, value};

std::cout << to_ostream(value) << std::endl;
// or 
std::cout << to_ostream(value, to_ostream::pretty) << std::endl;

// for compact printing use
std::cout << to_ostream(value, to_ostream::compact) << std::endl;

Output of the first to_ostream above is as shown below:

{
    "name" : "Timothy",
    "country" : "Nigeria",
    "favorites" : [ 34.351, -253, "@", "Nigeria", 34,
        {
            "name" : "Timothy",
            "country" : "Nigeria"
        }]
}

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Current Status

• High Precision numbers haven't been implemented for Value semmantics - slated for 28th Feb, 2015
• StreamReader and StreamWriter cannot cater for HighPrecision Numbers, and Binary - beta, slated for 20th March, 2015
• StreamReader already handles Strongly typed containers, but StreamWriter is yet to do so - 20th March, 2015
• The requirements for StreamType isn't well defined, yet. - slated for - 25th March, 2015

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Written and authored by Ibrahim Timothy Onogu. Please drop a comment.

http://ng.linkedin.com/pub/ibrahim-timothy-onogu/96/174/111