Read BSON file in Python?

Question

I want to read a BSON format Mongo dump in Python and process the data. I am using the Python bson package (which I'd prefer to use rather than have a pymongo dependency), but it doesn't explain how to read from a file.

This is what I'm trying:

bson_file = open('statistics.bson', 'rb')
b = bson.loads(bson_file)
print b[0]

But I get:

Traceback (most recent call last):
  File "test.py", line 11, in <module>
    b = bson.loads(bson_file)
  File "/Library/Python/2.7/site-packages/bson/__init__.py", line 75, in loads
    return decode_document(data, 0)[1]
  File "/Library/Python/2.7/site-packages/bson/codec.py", line 235, in decode_document
    length = struct.unpack("<i", data[base:base + 4])[0]
TypeError: 'file' object has no attribute '__getitem__'

What am I doing wrong?

Answer 1

The documentation states :

> help(bson.loads)
Given a BSON string, outputs a dict.

You need to pass a string. For example:

> b = bson.loads(bson_file.read())