Awesome
Piqi is a multi-format data serialization system for Erlang. It provides a uniform interface for serializing Erlang data structures to JSON, XML and Protocol Buffers formats.
A typical Piqi usage scenario involves the following steps:
1. Include Piqi as a rebar depedency -- add this entry to your
rebar.config
file:
{deps, [
...
{piqi, "", {git, "git://github.com/alavrik/piqi-erlang.git", {branch, "master"}}},
...
]}.
2. Describe data structures using the Piqi data definition language or
Protocol Buffers .proto
files
The Piqi data definition language can describe many
Erlang types, both primitive and user-defined. This includes integers, floats,
booleans, strings, binaries, lists, records and variants (i.e. {tag, Value}
tuples).
.piqi
modules can be converted to and from Protocol Buffers .proto
files:
piqi to-proto X.piqi
piqi of-proto X.proto
3. Call the Piqi compiler to generate Erlang type definitions and serialization code
4. Use generated serializes/deserializers in a user's program -- the desired serialization format can be specified at runtime. For examples:
% deserialize a data structure from Protocol Buffers
AddressBook = addressbook_piqi:parse_address_book(Bytes, 'pb'),
% serialize it as JSON
Json = addressbook_piqi:gen_address_book(AddressBook, 'json'),
% serialize it as pretty-printed JSON
JsonPretty = addressbook_piqi:gen_address_book(AddressBook, 'json_pretty'),
% serialize it as XML
Xml = addressbook_piqi:gen_address_book(AddressBook, 'xml').
Examples
See examples/addressbook and other projects in the examples directory.
Documentation
Piqi Erlang documentation is available at http://piqi.org/doc/erlang/
The master copy is located in the repository: doc/piqi-erlang.md
Bugs
Please report found problems using GitHub issues.
Mailing list
http://groups.google.com/group/piqi
Advanced installation
Sometimes, it may be useful or even necessary to use a custom version of the
piqi
binary executable instead of the pre-built one that comes with
piqi-erlang
.
For example, there may not be a pre-built piqi
for your platform. Or
organization policies may prohibit installing third-party binaries.
In this case, you can build the piqi
binary from source
code, put it somewhere in the local filesystem
and point to it using the PIQI
environment variable before running any
rebar
commands and starting the piqi
Erlang application. For example:
export PIQI=/usr/local/bin/piqi
Contributing
Your contributions are always welcome. Just open a pull request. Check TODO list for ideas.
Some useful commands:
make deps # the same as "rebar get-deps"
make # the same as "rebar compile"
make test
make dialyzer
make -C tests all test
make -C tests clean