The Django boundary iterators are used to help parse multi-part form data. These iterators are also general enough to be used in different contexts. The BoundaryIter class collaborates with other iterator classes such as ChunkIter and LazyStream. An example of these classes collaborating are illustrated below.
#Example; Using the Django boundary iterator.
#Imports.
from StringIO import StringIO
from django.http.multipartparser import ChunkIter, BoundaryIter, LazyStream
if __name__=="__main__":
#Boundary data.
b_boundary="-B-"
c_boundary="-C-"
#Example message with two boundaries.
_message="bdata%scdata%s"%(b_boundary, c_boundary)
#Instantiate a chunking iterator for file-like objects.
_chunk_iter=ChunkIter(StringIO(_message))
#Instantiate a lazy data stream using the chunking iterator.
_lazy_stream=LazyStream(_chunk_iter)
#Instantiate two boundary iterators.
_bboundary_iter=BoundaryIter(_lazy_stream, b_boundary)
_cboundary_iter=BoundaryIter(_lazy_stream, c_boundary)
#Display the parsed boundary data.
for data in _bboundary_iter:
print "%s: %s"%(b_boundary, data)
for data in _cboundary_iter:
print "%s: %s"%(c_boundary, data)
We finally display the results of iterating over the boundary iterators. By the time the second iterator is reached, the data stream is now shorter in length.