--- /dev/null
+# Codec
+
+High Performance, Feature-Rich Idiomatic Go codec/encoding library for
+binc, msgpack, cbor, json.
+
+Supported Serialization formats are:
+
+ - msgpack: https://github.com/msgpack/msgpack
+ - binc: http://github.com/ugorji/binc
+ - cbor: http://cbor.io http://tools.ietf.org/html/rfc7049
+ - json: http://json.org http://tools.ietf.org/html/rfc7159
+ - simple:
+
+To install:
+
+ go get github.com/ugorji/go/codec
+
+This package will carefully use 'unsafe' for performance reasons in specific places.
+You can build without unsafe use by passing the safe or appengine tag
+i.e. 'go install -tags=safe ...'. Note that unsafe is only supported for the last 3
+go sdk versions e.g. current go release is go 1.9, so we support unsafe use only from
+go 1.7+ . This is because supporting unsafe requires knowledge of implementation details.
+
+Online documentation: http://godoc.org/github.com/ugorji/go/codec
+Detailed Usage/How-to Primer: http://ugorji.net/blog/go-codec-primer
+
+The idiomatic Go support is as seen in other encoding packages in
+the standard library (ie json, xml, gob, etc).
+
+Rich Feature Set includes:
+
+ - Simple but extremely powerful and feature-rich API
+ - Support for go1.4 and above, while selectively using newer APIs for later releases
+ - Excellent code coverage ( > 90% )
+ - Very High Performance.
+ Our extensive benchmarks show us outperforming Gob, Json, Bson, etc by 2-4X.
+ - Careful selected use of 'unsafe' for targeted performance gains.
+ 100% mode exists where 'unsafe' is not used at all.
+ - Lock-free (sans mutex) concurrency for scaling to 100's of cores
+ - In-place updates during decode, with option to zero the value in maps and slices prior to decode
+ - Coerce types where appropriate
+ e.g. decode an int in the stream into a float, decode numbers from formatted strings, etc
+ - Corner Cases:
+ Overflows, nil maps/slices, nil values in streams are handled correctly
+ - Standard field renaming via tags
+ - Support for omitting empty fields during an encoding
+ - Encoding from any value and decoding into pointer to any value
+ (struct, slice, map, primitives, pointers, interface{}, etc)
+ - Extensions to support efficient encoding/decoding of any named types
+ - Support encoding.(Binary|Text)(M|Unm)arshaler interfaces
+ - Support IsZero() bool to determine if a value is a zero value.
+ Analogous to time.Time.IsZero() bool.
+ - Decoding without a schema (into a interface{}).
+ Includes Options to configure what specific map or slice type to use
+ when decoding an encoded list or map into a nil interface{}
+ - Mapping a non-interface type to an interface, so we can decode appropriately
+ into any interface type with a correctly configured non-interface value.
+ - Encode a struct as an array, and decode struct from an array in the data stream
+ - Option to encode struct keys as numbers (instead of strings)
+ (to support structured streams with fields encoded as numeric codes)
+ - Comprehensive support for anonymous fields
+ - Fast (no-reflection) encoding/decoding of common maps and slices
+ - Code-generation for faster performance.
+ - Support binary (e.g. messagepack, cbor) and text (e.g. json) formats
+ - Support indefinite-length formats to enable true streaming
+ (for formats which support it e.g. json, cbor)
+ - Support canonical encoding, where a value is ALWAYS encoded as same sequence of bytes.
+ This mostly applies to maps, where iteration order is non-deterministic.
+ - NIL in data stream decoded as zero value
+ - Never silently skip data when decoding.
+ User decides whether to return an error or silently skip data when keys or indexes
+ in the data stream do not map to fields in the struct.
+ - Encode/Decode from/to chan types (for iterative streaming support)
+ - Drop-in replacement for encoding/json. `json:` key in struct tag supported.
+ - Provides a RPC Server and Client Codec for net/rpc communication protocol.
+ - Handle unique idiosyncrasies of codecs e.g.
+ - For messagepack, configure how ambiguities in handling raw bytes are resolved
+ - For messagepack, provide rpc server/client codec to support
+ msgpack-rpc protocol defined at:
+ https://github.com/msgpack-rpc/msgpack-rpc/blob/master/spec.md
+
+## Extension Support
+
+Users can register a function to handle the encoding or decoding of
+their custom types.
+
+There are no restrictions on what the custom type can be. Some examples:
+
+ type BisSet []int
+ type BitSet64 uint64
+ type UUID string
+ type MyStructWithUnexportedFields struct { a int; b bool; c []int; }
+ type GifImage struct { ... }
+
+As an illustration, MyStructWithUnexportedFields would normally be
+encoded as an empty map because it has no exported fields, while UUID
+would be encoded as a string. However, with extension support, you can
+encode any of these however you like.
+
+## Custom Encoding and Decoding
+
+This package maintains symmetry in the encoding and decoding halfs.
+We determine how to encode or decode by walking this decision tree
+
+ - is type a codec.Selfer?
+ - is there an extension registered for the type?
+ - is format binary, and is type a encoding.BinaryMarshaler and BinaryUnmarshaler?
+ - is format specifically json, and is type a encoding/json.Marshaler and Unmarshaler?
+ - is format text-based, and type an encoding.TextMarshaler?
+ - else we use a pair of functions based on the "kind" of the type e.g. map, slice, int64, etc
+
+This symmetry is important to reduce chances of issues happening because the
+encoding and decoding sides are out of sync e.g. decoded via very specific
+encoding.TextUnmarshaler but encoded via kind-specific generalized mode.
+
+Consequently, if a type only defines one-half of the symmetry
+(e.g. it implements UnmarshalJSON() but not MarshalJSON() ),
+then that type doesn't satisfy the check and we will continue walking down the
+decision tree.
+
+## RPC
+
+RPC Client and Server Codecs are implemented, so the codecs can be used
+with the standard net/rpc package.
+
+## Usage
+
+Typical usage model:
+
+ // create and configure Handle
+ var (
+ bh codec.BincHandle
+ mh codec.MsgpackHandle
+ ch codec.CborHandle
+ )
+
+ mh.MapType = reflect.TypeOf(map[string]interface{}(nil))
+
+ // configure extensions
+ // e.g. for msgpack, define functions and enable Time support for tag 1
+ // mh.SetExt(reflect.TypeOf(time.Time{}), 1, myExt)
+
+ // create and use decoder/encoder
+ var (
+ r io.Reader
+ w io.Writer
+ b []byte
+ h = &bh // or mh to use msgpack
+ )
+
+ dec = codec.NewDecoder(r, h)
+ dec = codec.NewDecoderBytes(b, h)
+ err = dec.Decode(&v)
+
+ enc = codec.NewEncoder(w, h)
+ enc = codec.NewEncoderBytes(&b, h)
+ err = enc.Encode(v)
+
+ //RPC Server
+ go func() {
+ for {
+ conn, err := listener.Accept()
+ rpcCodec := codec.GoRpc.ServerCodec(conn, h)
+ //OR rpcCodec := codec.MsgpackSpecRpc.ServerCodec(conn, h)
+ rpc.ServeCodec(rpcCodec)
+ }
+ }()
+
+ //RPC Communication (client side)
+ conn, err = net.Dial("tcp", "localhost:5555")
+ rpcCodec := codec.GoRpc.ClientCodec(conn, h)
+ //OR rpcCodec := codec.MsgpackSpecRpc.ClientCodec(conn, h)
+ client := rpc.NewClientWithCodec(rpcCodec)
+
+## Running Tests
+
+To run tests, use the following:
+
+ go test
+
+To run the full suite of tests, use the following:
+
+ go test -tags alltests -run Suite
+
+You can run the tag 'safe' to run tests or build in safe mode. e.g.
+
+ go test -tags safe -run Json
+ go test -tags "alltests safe" -run Suite
+
+## Running Benchmarks
+
+Please see http://github.com/ugorji/go-codec-bench .
+
+## Caveats
+
+Struct fields matching the following are ignored during encoding and decoding
+
+ - struct tag value set to -
+ - func, complex numbers, unsafe pointers
+ - unexported and not embedded
+ - unexported and embedded and not struct kind
+ - unexported and embedded pointers (from go1.10)
+
+Every other field in a struct will be encoded/decoded.
+
+Embedded fields are encoded as if they exist in the top-level struct,
+with some caveats. See Encode documentation.
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