Python 3 support for the testsuite

Dockerfile.test

-FROM python:2-alpine
+ARG PYTHON_VERSION=2
+FROM python:${PYTHON_VERSION}-alpine
 
 WORKDIR /usr/src/app/
 COPY nginx-ldap-auth-daemon.py /usr/src/app/

t/README

 To run tests use supplied Dockerfile.test:
 
-docker build -f Dockerfile.test -t my-tag .
+docker build -f Dockerfile.test -t my-tag
+
+If you desire to use a container with Python3, you can supply an appropriate
+build argument:
+
+docker build -f Dockerfile.test -t my-tag --build-arg PYTHON_VERSION=3 .
 docker run my-tag
 
 To run without Docker:

t/ldap-auth.t

@@ -433,7 +433,7 @@ system("ldapadd -H ldap://127.0.0.1:$p5 -x -D \"cn=root,ou=Users,dc=test,dc=loca
 $t->write_file_expand("auth_daemon.sh", <<"EOF");
 AUTHBIN=\$(realpath $AUTHD)
 cd $d
-exec coverage2 run \$AUTHBIN --host 127.0.0.1 \\
+exec coverage run \$AUTHBIN --host 127.0.0.1 \\
     -p %%PORT_8888%% >$d/nginx-ldap-auth-dameon.stdlog 2>&1
 EOF
 

t/runtests.sh

@@ -10,4 +10,4 @@ perl ldap-auth.t
 
 testdir=$(find /tmp -name 'nginx-test-*' -print -quit)
 cd $testdir
-coverage2 html && printf "Coverage report: docker cp <cid>:$testdir/htmlcov <hostdir>\n"
+coverage html && printf "Coverage report: docker cp <cid>:$testdir/htmlcov <hostdir>\n"