Source code for vcr.serialize
import yaml
from vcr.request import Request
from vcr.serializers import compat
# version 1 cassettes started with VCR 1.0.x.
# Before 1.0.x, there was no versioning.
CASSETTE_FORMAT_VERSION = 1
"""
Just a general note on the serialization philosophy here:
I prefer cassettes to be human-readable if possible. Yaml serializes
bytestrings to !!binary, which isn't readable, so I would like to serialize to
strings and from strings, which yaml will encode as utf-8 automatically.
All the internal HTTP stuff expects bytestrings, so this whole serialization
process feels backwards.
Serializing: bytestring -> string (yaml persists to utf-8)
Deserializing: string (yaml converts from utf-8) -> bytestring
"""
def _looks_like_an_old_cassette(data):
return isinstance(data, list) and len(data) and "request" in data[0]
def _warn_about_old_cassette_format():
raise ValueError(
"Your cassette files were generated in an older version "
"of VCR. Delete your cassettes or run the migration script."
"See http://git.io/mHhLBg for more details.",
)
[docs]
def deserialize(cassette_string, serializer):
try:
data = serializer.deserialize(cassette_string)
# Old cassettes used to use yaml object thingy so I have to
# check for some fairly stupid exceptions here
except (ImportError, yaml.constructor.ConstructorError):
_warn_about_old_cassette_format()
if _looks_like_an_old_cassette(data):
_warn_about_old_cassette_format()
requests = [Request._from_dict(r["request"]) for r in data["interactions"]]
responses = [compat.convert_to_bytes(r["response"]) for r in data["interactions"]]
return requests, responses
[docs]
def serialize(cassette_dict, serializer):
interactions = [
{
"request": compat.convert_to_unicode(request._to_dict()),
"response": compat.convert_to_unicode(response),
}
for request, response in zip(cassette_dict["requests"], cassette_dict["responses"])
]
data = {"version": CASSETTE_FORMAT_VERSION, "interactions": interactions}
return serializer.serialize(data)