This library implements a strict BSON encoder and decoder to and from
bson:document()
s. This library is meant to be included into any project which
requires very explicit BSON serialization; no dependencies on any database
drivers exist. bson_validate:valid/1
offers checking of Erlang terms for
conformance to the bson:document()
constraints. bson:decode/1
will always
return a valid bson:document()
but bson:encode/1
does no checking of its
input and assumes compliance with the constraints of bson:document()
.
The functions bson:encode/1
and bson:decode/1
are inverse of one another, as
confirmed in test/bson_SUITE.erl
. A heuristic encoder is intended future work
but it will not, when composed with bson:decode/1
be the identity function of
bson:document()
.
How do you use this crazy thing? If you don't know the BSON v1.0 specification
please read it here. Once you've got that
under your belt, the type heirarchy of include/bson.hrl
should make a fair
bit of sense; I've striven to document this project thoroughly at the source
level.
Building bson
is a quick make
. All dependencies will be pulled in and
compiled. Get an Erlang shell using your preferred method. Now, here's a
document that encodes a few well known things:
> D = {document, [{"motto", {string, "We'll do it live!"}}, {"pi-ish", {double, 3.141}}]}.
Encode it:
> bson:encode(D).
<<50,0,0,0,2,109,111,116,116,111,0,18,0,0,0,87,101,39,108,
108,32,100,111,32,105,116,32,108,105,...>>
> io:format("~p~n", [bson:encode(D)]).
<<50,0,0,0,2,109,111,116,116,111,0,18,0,0,0,87,101,39,108,108,32,100,111,32,
105,116,32,108,105,118,101,33,0,1,112,105,45,105,115,104,0,84,227,165,155,
196,32,9,64,0>>
You can pick that apart and get back the original document if you'd like but have the machine do it for you!
> bson:decode( bson:encode(D) ).
{document,[{"motto",{string,"We'll do it live!"}},
{"pi-ish",{double,3.141}}]}
Happy hacking!
This is early stage software, v0.1.0. It's only been tested against itself and may not exactly understand BSON as it's implemented in the wild. I'll be extending the test suite to check against external, common implementations in a future release.