Running Linter as Part of CI Jobs (#27)

* Adding Travis config

* Added CI badge

* Running linters with CI

* Anchoring pylint version to 1.6.4; More recent versions have a bug where they mistakenly issue warnings for imports like google.auth (pylint-dev/pylint#1084)

* Running linter only on Python 2

* More argument validation and other best practices for bash commands

.travis.yml

@@ -5,5 +5,8 @@ python:
   - "3.5"
 # command to install dependencies
 install: "pip install -r requirements.txt"
+before_script: 
+  - export PY_VERSION=`python -c 'import sys; print sys.version_info.major'`
+  - if [[ "$PY_VERSION" == '2' ]]; then ./lint.sh all; fi
 # command to run tests
 script: pytest

lint.sh

@@ -28,13 +28,27 @@ function lintChangedFiles () {
   done
 }
 
+set -o errexit
+set -o nounset
+
 SKIP_FOR_TESTS="redefined-outer-name,protected-access,missing-docstring"
 
-if [[ $1 = "all" ]]
+if [[ "$#" -eq 1 && "$1" = "all" ]]
+then
+  CHECK_ALL=true  
+elif [[ "$#" -eq  0 ]]
+then
+  CHECK_ALL=false
+else
+  echo "Usage: ./lint.sh [all]"
+  exit 1
+fi
+
+if [[ "$CHECK_ALL" = true ]]
 then
-  lintAllFiles firebase_admin
-  lintAllFiles tests $SKIP_FOR_TESTS
+  lintAllFiles "firebase_admin" ""
+  lintAllFiles "tests" "$SKIP_FOR_TESTS"
 else
-  lintChangedFiles firebase_admin
-  lintChangedFiles tests $SKIP_FOR_TESTS
+  lintChangedFiles "firebase_admin" ""
+  lintChangedFiles "tests" "$SKIP_FOR_TESTS"
 fi

requirements.txt

@@ -1,4 +1,4 @@
-pylint >= 1.6.4
+pylint == 1.6.4
 pytest >= 3.0.6
 pytest-cov >= 2.4.0
 tox >= 2.6.0