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BSON::Simple zef:japhb last updated on 2021-07-26


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BSON::Simple - Simple codec for the BSON (Binary JSON) serialization format


use BSON::Simple;

# Encode a Raku value to BSON, or vice-versa
my $bson = bson-encode($value);
my $val1 = bson-decode($bson);              # Dies if more data past first decoded document
my $val2 = bson-decode($bson, my $pos = 0); # Updates $pos after decoding first document

# Request warnings when decoding deprecated BSON element types
# (default is to ignore deprecations and handle all known element types)
my $bad  = bson-decode($deprecated);     # Warns, but returns decoding anyway

# Decode into default Raku Hash and Blob types, instead of ordered hashes
# and wrapped BSON::Simple::Binary objects
my $simple = bson-decode($bson);


BSON::Simple is a trivial implementation of the core functionality of the BSON serialization format, used as the primary data format of the MongoDB document-oriented database.

Note that because it is important to retain key order, BSON maps are decoded as ordered hashes using the Hash::Ordered module. Likewise, several BSON types that must maintain a distinction from Raku's standard types are decoded into objects that do the BSON::Simple::Special role.

If you would prefer to decode into standard (unordered) Raku hashes, you can set the $*BSON_SIMPLE_PLAIN_HASHES dynamic variable to True. Likewise, if you would prefer to decode default-subtype Binary fields into plain Raku Blob objects (rather than wrapped into a BSON::Simple::Binary object), set the $*BSON_SIMPLE_PLAIN_BLOBS dynamic variable to True.



The older BSON Raku module also implements the BSON format. It has a much more detailed API, making it considerably more verbose in actual usage than BSON::Simple. It is also more difficult to adapt as one optional encoding among many for a generic data service (which might serve CSV, JSON, CBOR, and BSON, for example). Finally, its internal design makes it somewhat more difficult to optimize, as it was written before modern buffer handling was added to Raku and before parallelism overhead was fully understood.

On the other hand, that original BSON module has a decade of real world testing and many hundreds of commits behind it, and this module is brand new.

To see how this module compares to other data serialization modules, see serializer-perf .


Geoffrey Broadwell [email protected]


Copyright 2021 Geoffrey Broadwell

This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.