mongoengine/tests/test_replicaset_connection.py
Stefan Wójcik 9170eea784
Rename MongoEngineConnectionError to ConnectionFailure (#2111)
I originally changed the exception name from `ConnectionError` to
`MongoEngineConnectionError` in
b02904ee75,
inspired by landscape.io's package health report, which argued that
`ConnectionError` is already a built-in exception in Python 3 (which it is:
https://docs.python.org/3/library/exceptions.html#ConnectionError).

I do agree that we shouldn't override built-in exceptions. [0] That said, it’s
silly to add a "MongoEngine" prefix to any class within the `mongoengine`
module (and *especially* to *just one* exception class out of many). I've
decided to do what PyMongo does (
8855a510a8/pymongo/errors.py (L59))
and call this exception `ConnectionFailure`.

Note that this is a breaking change and people will need to rename
`MongoEngineConnectionError`s in their code to `ConnectionFailure`. Moreover,
if they use PyMongo's `ConnectionFailure` for anything, they'll need to take
    extra care to avoid conflicts, e.g. by using:
```
from mongoengine import ConnectionFailure as MongoEngineConnectionFailure
```

[0] Note that some popular packages still overwrite `ConnectionError`, e.g.
4983a9bde3/requests/exceptions.py (L32)
or
0be4d29206/redis/exceptions.py (L8)
2019-06-30 09:23:32 +02:00

47 lines
1.2 KiB
Python

import unittest
from pymongo import ReadPreference
from pymongo import MongoClient
import mongoengine
from mongoengine.connection import ConnectionFailure
CONN_CLASS = MongoClient
READ_PREF = ReadPreference.SECONDARY
class ConnectionTest(unittest.TestCase):
def setUp(self):
mongoengine.connection._connection_settings = {}
mongoengine.connection._connections = {}
mongoengine.connection._dbs = {}
def tearDown(self):
mongoengine.connection._connection_settings = {}
mongoengine.connection._connections = {}
mongoengine.connection._dbs = {}
def test_replicaset_uri_passes_read_preference(self):
"""Requires a replica set called "rs" on port 27017
"""
try:
conn = mongoengine.connect(
db="mongoenginetest",
host="mongodb://localhost/mongoenginetest?replicaSet=rs",
read_preference=READ_PREF,
)
except ConnectionFailure as e:
return
if not isinstance(conn, CONN_CLASS):
# really???
return
self.assertEqual(conn.read_preference, READ_PREF)
if __name__ == "__main__":
unittest.main()