BsonUser Guide
Overview
Bson is an implementation of the BSON specification complete with BSON serialisation and deserialisation.
Bson was created to support the development of the Alien-Factory MongoDB driver.
Quick Start
1). Create a text file called Example.fan
:
using afBson class Example { Void main() { buf := Buf() documentIn := [ "_id" : ObjectId(), "name" : "Dave", "age" : 42 ]// serialise BSON to a streamBsonWriter(buf.out).writeDocument(documentIn)// deserialise BSOM from a streamdocumentOut := BsonReader(buf.flip.in).readDocument echo(documentOut) } }
2). Run Example.fan
as a Fantom script from the command line:
C:\> fan Example.fan [_id:53503531a8000b8b44000001, name:Dave, age:42]
Usage
The main BsonReader and BsonWriter classes (de)serialise BSON objects to and from Fantom using the following mapping:
BSON Fantom --------------------------------- ARRAY -> sys::List BINARY -> afBson::Binary BOOLEAN -> sys::Bool CODE -> afBson::Code CODE_W_SCOPE -> afBson::Code DATE -> sys::DateTime DOCUMENT -> sys::Map DOUBLE -> sys::Float INTEGER_64 -> sys::Int MAX_KEY -> afBson::MaxKey MIN_KEY -> afBson::MinKey NULL -> null OBJECT_ID -> afBson::ObjectId REGEX -> sys::Regex STRING -> sys::Str TIMESTAMP -> afBson::Timestamp
Note that the deprecated BSON constructs UNDEFINED
, DB_POINTER
and SYMBOL
are ignored and have no Fantom representation.
Bson
takes care of all the tricky Endian
ness. All BSON objects (except for Buf
and Regex) may also be serialised to and from strings using Fantom's standard serialisation techniques.
CAUTION:
INTEGER_32
values will be read as Int values. If you then write its containing document, the storage type will be converted toINTEGER_64
.
This is only of concern if other, non Fantom, drivers have written INTEGER_32
values to the database.
CAUTION: Fantom does not support regex flags. When reading a BSON regex, flags are convered into embedded characted flags. e.g.
/myregex/im
is converted into/(?im)myregex/
. See Java's Pattern class for a list of supported flags (dimsuxU).
Again, this is only of concern if other, non Fantom, drivers have written REGEX
values (with flags) to the database.
The Alien-Factoy BSON library was inspired by fantomongo by Liam Staskawicz.