Update for python 2.x and 3.x builds (#988)

.github/workflows/run-tests.yaml

@@ -1,35 +1,58 @@
 
-name: mininet tests
+name: mininet-tests
 
 on: [push, pull_request]
 
 jobs:
   test:
-    name: Mininet-tests
+    name: Mininet Tests
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
         os: [ubuntu-18.04, ubuntu-16.04]
+        python-version: [3.x, 2.x]
     steps:
-      - name: Checking out Mininet source
+      - name: Check out Mininet source
         uses: actions/checkout@v2
-      - name: Installing dependencies
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v2
+        with:
+          python-version: ${{ matrix.python-version }}
+      - name: Install Mininet and base dependencies
         run: |
           sudo apt-get update -qq
-          sudo apt-get install -qq vlan
-          PYTHON=`which python` util/install.sh -n
-          pip install pexpect || pip3 install pexpect
-      - name: Code Check
+          # This seems too slow unfortunately:
+          # sudo apt-get upgrade -y -qq
+          PYTHON=`which python` util/install.sh -nv
+      - name: Run code check (skipping for now)
         run: |
           bash -c "if [ `lsb_release -rs` == '14.04' ]; then make codecheck; fi"
-      - name: Install
+      - name: Sanity test
         run: |
-          util/install.sh -fvw
-      - name: Building and running tests
+          export sudo="sudo env PATH=$PATH"
+          # Verify major python-version number matches python and mininet
+          export PYVER=`echo ${{ matrix.python-version }} | cut -d . -f 1`
+          export CHKVER='px import platform; print(platform.python_version())'
+          python --version |& grep " $PYVER\."
+          echo $CHKVER | $sudo mn -v output | grep " $PYVER\."
+          # Newer OvS tries OpenFlow15 which crashes ovsc on ubuntu-20.04
+          $sudo mn --switch ovs,protocols=OpenFlow13 --test pingall
+      - name: Install test dependencies
         run: |
-          alias sudo="sudo env PATH=$PATH"
+          sudo apt-get install -qq vlan
+          pip install pexpect
+          util/install.sh -fw
+      - name: Run tests (quick)
+        run: |
+          export sudo="sudo env PATH=$PATH"
           export PYTHON=`which python`
-          echo 'px import sys; print(sys.version_info)' | sudo $PYTHON bin/mn -v output
-          sudo $PYTHON bin/mn --test pingall
-          sudo $PYTHON mininet/test/runner.py -v -quick
-          sudo $PYTHON examples/test/runner.py -v -quick
+          rm -f pexpect.out
+          $sudo $PYTHON mininet/test/runner.py -v -quick || \
+            (cat pexpect.out && exit 1)
+      - name: Run examples tests (quick)
+        run: |
+          export sudo="sudo env PATH=$PATH"
+          export PYTHON=`which python`
+          rm -f pexpect.out
+          $sudo $PYTHON examples/test/runner.py -v -quick || \
+            (cat pexpect.out && exit 1)