Address collections.abc import warning introduced in Python 3.7

[peteryin21]

Description

In Python 3.7, I am seeing the following warnings from this library:

 /usr/local/lib/python3.7/site-packages/jose/jwt.py:5: DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated, and in 3.8 it will stop working
from collections import Mapping
/usr/local/lib/python3.7/site-packages/jose/jws.py:6: DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated, and in 3.8 it will stop working
from collections import Mapping, Iterable

This warning was introduced in this CPython commit.

To ensure future compatibility with Python 3.8, I've updated these imports to try importing from collections.abc and fall back to collections to keep backward compatibility with Python 2.

In addition, I made a few updates to the requirements-dev.txt that I needed to run the tests in Python 3.7.

• Added conditional to only install wsgiref in Python 2, since it's not supported in Python 3 (and is instead included in the standard library)
• Removed ecdsa since it is a duplicate requirement from requirements.txt and pip complains

Double requirement given: ecdsa (from -r requirements.txt (line 5)) (already in ecdsa==0.13 (from -r requirements-dev.txt (line 10)), name='ecdsa')

• Updated pytest, py, pytest-cov, coverage, and coveralls packages to get tests to pass with Python 2 and 3.
• Added cryptography package required for tests.

Testing

I created a virtualenv with both Python 2.7.14 and Python 3.7.1, ran pip install -r requirements-dev.txt and then ran the tests with pytest tests. Output below

Python 2.7.14

(venv2) ➜ python-jose git:(master) ✗ pytest tests
================================================================================================================================= test session starts =================================================================================================================================
platform darwin -- Python 2.7.14, pytest-4.1.1, py-1.5.4, pluggy-0.8.1
rootdir: /Users/peteryin/code/open_source/python-jose, inifile: setup.cfg
plugins: cov-2.6.1
collected 184 items
tests/test_firebase.py ... [ 1%]
tests/test_jwk.py ......... [ 6%]
tests/test_jws.py ...................................... [ 27%]
tests/test_jwt.py ................................................. [ 53%]
tests/test_utils.py .. [ 54%]
tests/algorithms/test_EC.py ......................... [ 68%]
tests/algorithms/test_HMAC.py ... [ 70%]
tests/algorithms/test_RSA.py .................................................. [ 97%]
tests/algorithms/test_base.py .. [ 98%]
tests/rfc/test_rfc7520.py ... [100%]
================================================================================================================================== warnings summary ===================================================================================================================================
tests/test_jwt.py::TestJWT::test_invalid_claims_json
/Users/peteryin/code/open_source/python-jose/tests/test_jwt.py:65: PytestDeprecationWarning: The 'message' parameter is deprecated.
(did you mean to use `match='some regex'` to check the exception message?)
Please comment on https://github.com/pytest-dev/pytest/issues/3974 if you have concerns about removal of this parameter.
with pytest.raises(JWTError, message='Invalid payload string: ["a", "b"}'):
tests/test_jwt.py::TestJWT::test_invalid_claims
/Users/peteryin/code/open_source/python-jose/tests/test_jwt.py:80: PytestDeprecationWarning: The 'message' parameter is deprecated.
(did you mean to use `match='some regex'` to check the exception message?)
Please comment on https://github.com/pytest-dev/pytest/issues/3974 if you have concerns about removal of this parameter.
with pytest.raises(JWTError, message='Invalid payload string: must be a json object'):
-- Docs: https://docs.pytest.org/en/latest/warnings.html
---------- coverage: platform darwin, python 2.7.14-final-0 ----------
Name Stmts Miss Cover Missing
-------------------------------------------------------------
tests/__init__.py 0 0 100%
tests/algorithms/__init__.py 0 0 100%
tests/algorithms/test_EC.py 79 0 100%
tests/algorithms/test_HMAC.py 32 0 100%
tests/algorithms/test_RSA.py 121 1 99% 17
tests/algorithms/test_base.py 11 0 100%
tests/rfc/__init__.py 0 0 100%
tests/rfc/test_rfc7520.py 20 0 100%
tests/test_firebase.py 12 0 100%
tests/test_jwk.py 65 0 100%
tests/test_jws.py 161 0 100%
tests/test_jwt.py 286 0 100%
tests/test_utils.py 9 0 100%
-------------------------------------------------------------
TOTAL 796 1 99%
======================================================================================================================= 184 passed, 2 warnings in 12.12 seconds =======================================================================================================================

Python 3.7.1

(venv3) ➜ python-jose git:(master) ✗ pytest tests
================================================================================================================================= test session starts =================================================================================================================================
platform darwin -- Python 3.7.1, pytest-4.1.1, py-1.5.4, pluggy-0.8.1
rootdir: /Users/peteryin/code/open_source/python-jose, inifile: setup.cfg
plugins: cov-2.6.1
collected 184 items
tests/test_firebase.py ... [ 1%]
tests/test_jwk.py ......... [ 6%]
tests/test_jws.py ...................................... [ 27%]
tests/test_jwt.py ................................................. [ 53%]
tests/test_utils.py .. [ 54%]
tests/algorithms/test_EC.py ......................... [ 68%]
tests/algorithms/test_HMAC.py ... [ 70%]
tests/algorithms/test_RSA.py .................................................. [ 97%]
tests/algorithms/test_base.py .. [ 98%]
tests/rfc/test_rfc7520.py ... [100%]
================================================================================================================================== warnings summary ===================================================================================================================================
tests/test_jwt.py::TestJWT::test_invalid_claims_json
/Users/peteryin/code/open_source/python-jose/tests/test_jwt.py:65: PytestDeprecationWarning: The 'message' parameter is deprecated.
(did you mean to use `match='some regex'` to check the exception message?)
Please comment on https://github.com/pytest-dev/pytest/issues/3974 if you have concerns about removal of this parameter.
with pytest.raises(JWTError, message='Invalid payload string: ["a", "b"}'):
tests/test_jwt.py::TestJWT::test_invalid_claims
/Users/peteryin/code/open_source/python-jose/tests/test_jwt.py:80: PytestDeprecationWarning: The 'message' parameter is deprecated.
(did you mean to use `match='some regex'` to check the exception message?)
Please comment on https://github.com/pytest-dev/pytest/issues/3974 if you have concerns about removal of this parameter.
with pytest.raises(JWTError, message='Invalid payload string: must be a json object'):
-- Docs: https://docs.pytest.org/en/latest/warnings.html
---------- coverage: platform darwin, python 3.7.1-final-0 -----------
Name Stmts Miss Cover Missing
-------------------------------------------------------------
tests/__init__.py 0 0 100%
tests/algorithms/__init__.py 0 0 100%
tests/algorithms/test_EC.py 79 0 100%
tests/algorithms/test_HMAC.py 32 0 100%
tests/algorithms/test_RSA.py 121 0 100%
tests/algorithms/test_base.py 11 0 100%
tests/rfc/__init__.py 0 0 100%
tests/rfc/test_rfc7520.py 20 0 100%
tests/test_firebase.py 12 0 100%
tests/test_jwk.py 65 0 100%
tests/test_jws.py 161 0 100%
tests/test_jwt.py 286 0 100%
tests/test_utils.py 9 0 100%
-------------------------------------------------------------
TOTAL 796 0 100%
======================================================================================================================= 184 passed, 2 warnings in 12.07 seconds =======================================================================================================================

There are some additional deprecation warnings that are coming from pytest, but I decided to stay conservative with the scope of this PR since it's my first contribution to this library.

[codecov]

Codecov Report

Merging #124 into master will increase coverage by 0.03%.
The diff coverage is 100%.

@@ Coverage Diff @@## master #124 +/- ##
==========================================
+ Coverage 94.6% 94.63% +0.03% 
==========================================
Files 13 13 Lines 1000 1006 +6 ==========================================
+ Hits 946 952 +6 
Misses 54 54

Impacted Files	Coverage Δ
jose/jwt.py	100% <100%> (ø)	⬆️
jose/jws.py	96.72% <100%> (+0.08%)	⬆️

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[peteryin21]

@mpdavis I grew up in Ames. Crazy coincidence!

[peteryin21]

@zejn Tagging you because it looks like you are also a maintainer based on some recently merged PRs. Any tips for getting this PR shipped?

[zejn]

This still looks good. Thank you for your first contribution.