Require Python 3 and remove support for Python 2.

Python 2 reaches end-of-life on January 1, 2020, which is only
a few months away.  This means that OVS needs to stop depending
on in the next release that should occur roughly that same time.
Therefore, this commit removes all support for Python 2.  It
also makes Python 3 a mandatory build dependency.

Some of the interesting consequences:

- HAVE_PYTHON, HAVE_PYTHON2, and HAVE_PYTHON3 conditionals have
  been removed, since we now know that Python3 is available.

- $PYTHON and $PYTHON2 are removed, and $PYTHON3 is always
  available.

- Many tests for Python 2 support have been removed, and the ones
  that depended on Python 3 now run unconditionally.  This allowed
  several macros in the testsuite to be removed, making the code
  clearer.  This does make some of the changes to the testsuite
  files large due to indentation level changes.

- #! lines for Python now use /usr/bin/python3 instead of
  /usr/bin/python.

- Packaging depends on Python 3 packages.

Acked-by: Numan Siddique <nusiddiq@redhat.com>
Tested-by: Numan Siddique <nusiddiq@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

8 files changed, 23 insertions, 23 deletions

diff --git a/debian/.gitignore b/debian/.gitignore
index 441a8ffb7..d02526b21 100644
--- a/debian/.gitignore
+++ b/debian/.gitignore
@@ -23,4 +23,5 @@
 /openvswitch-testcontroller
 /openvswitch-vtep
 /python-openvswitch
+/python3-openvswitch
 /tmp
diff --git a/debian/automake.mk b/debian/automake.mk
index 03a1d68c2..37b1a2433 100644
--- a/debian/automake.mk
+++ b/debian/automake.mk
@@ -52,8 +52,8 @@ EXTRA_DIST += \
 	debian/openvswitch-vtep.init \
 	debian/openvswitch-vtep.install \
 	debian/openvswitch-vtep.manpages \
-	debian/python-openvswitch.dirs \
-	debian/python-openvswitch.install \
+	debian/python3-openvswitch.dirs \
+	debian/python3-openvswitch.install \
 	debian/rules \
 	debian/rules.modules \
 	debian/ifupdown.sh \
diff --git a/debian/control b/debian/control
index 2ad35f2ce..ad4b18786 100644
--- a/debian/control
+++ b/debian/control
@@ -13,10 +13,10 @@ Build-Depends: graphviz,
                libtool,
                openssl,
                procps,
-               python-all (>= 2.7),
-               python-twisted-conch,
-               python-zopeinterface,
-               python-six,
+               python3-all,
+               python3-twisted-conch,
+               python3-zopeinterface,
+               python3-six,
                libunbound-dev
 Standards-Version: 3.9.3
 Homepage: http://openvswitch.org/
@@ -41,7 +41,7 @@ Description: Open vSwitch datapath module source - module-assistant version
 
 Package: openvswitch-datapath-dkms
 Architecture: all
-Depends: dkms (>= 1.95), libc6-dev, libelf-dev, make, ${misc:Depends}, ${python:Depends}
+Depends: dkms (>= 1.95), libc6-dev, libelf-dev, make, ${misc:Depends}, ${python3:Depends}
 Description: Open vSwitch datapath module source - DKMS version
  Open vSwitch is a production quality, multilayer, software-based,
  Ethernet virtual switch. It is designed to enable massive network
@@ -58,8 +58,8 @@ Description: Open vSwitch datapath module source - DKMS version
 Package: openvswitch-common
 Architecture: linux-any
 Multi-Arch: foreign
-Depends: python (>= 2.7),
-         python-six,
+Depends: python3,
+         python3-six,
          libopenvswitch (= ${binary:Version}),
          ${misc:Depends},
          ${shlibs:Depends}
@@ -102,10 +102,9 @@ Depends: kmod | module-init-tools,
          netbase,
          openvswitch-common (= ${binary:Version}),
          procps,
-         python-argparse,
          uuid-runtime,
          ${misc:Depends},
-         ${python:Depends},
+         ${python3:Depends},
          ${shlibs:Depends}
 Description: Open vSwitch switch implementations
  Open vSwitch is a production quality, multilayer, software-based,
@@ -171,10 +170,10 @@ Description: Debug symbols for Open vSwitch packages
  packages.  Install it to debug one of them or to examine a core dump
  produced by one of them.
 
-Package: python-openvswitch
+Package: python3-openvswitch
 Architecture: all
 Section: python
-Depends: ${misc:Depends}, ${python:Depends}, python-six
+Depends: ${misc:Depends}, ${python3:Depends}, python3-six
 Description: Python bindings for Open vSwitch
  Open vSwitch is a production quality, multilayer, software-based,
  Ethernet virtual switch. It is designed to enable massive network
@@ -188,10 +187,10 @@ Description: Python bindings for Open vSwitch
 
 Package: openvswitch-test
 Architecture: all
-Depends: python (>= 2.7) | python-argparse,
-         python-twisted-web,
+Depends: python3,
+         python3-twisted-web,
          ${misc:Depends},
-         ${python:Depends}
+         ${python3:Depends}
 Description: Open vSwitch test package
  Open vSwitch is a production quality, multilayer, software-based,
  Ethernet virtual switch. It is designed to enable massive network
@@ -208,8 +207,8 @@ Package: openvswitch-vtep
 Architecture: linux-any
 Depends: openvswitch-common (>= ${binary:Version}),
          openvswitch-switch (>= ${binary:Version}),
-         python,
-         python-openvswitch (>= ${source:Version}),
+         python3,
+         python3-openvswitch (>= ${source:Version}),
          ${misc:Depends},
          ${shlibs:Depends}
 Description: Open vSwitch VTEP utilities
@@ -250,8 +249,8 @@ Architecture: linux-any
 Depends: iproute2,
          openvswitch-common (= ${binary:Version}),
          openvswitch-switch (= ${binary:Version}),
-         python,
-         python-openvswitch (= ${source:Version}),
+         python3,
+         python3-openvswitch (= ${source:Version}),
          strongswan,
          ${misc:Depends},
          ${shlibs:Depends}
diff --git a/debian/openvswitch-test.install b/debian/openvswitch-test.install
index 8a01a5125..cb371c906 100644
--- a/debian/openvswitch-test.install
+++ b/debian/openvswitch-test.install
@@ -1,3 +1,3 @@
 usr/bin/ovs-l3ping
 usr/bin/ovs-test
-usr/share/openvswitch/python/ovstest usr/lib/python2.7/dist-packages/
+usr/share/openvswitch/python/ovstest usr/lib/python3.7/dist-packages/
diff --git a/debian/python-openvswitch.install b/debian/python-openvswitch.install
deleted file mode 100644
index 0472d413f..000000000
--- a/debian/python-openvswitch.install
+++ /dev/null
@@ -1 +0,0 @@
-usr/share/openvswitch/python/ovs usr/lib/python2.7/dist-packages/
diff --git a/debian/python-openvswitch.dirs b/debian/python3-openvswitch.dirs
index cbf0de33d..cbf0de33d 100644
--- a/debian/python-openvswitch.dirs
+++ b/debian/python3-openvswitch.dirs
diff --git a/debian/python3-openvswitch.install b/debian/python3-openvswitch.install
new file mode 100644
index 000000000..7ba956e3b
--- /dev/null
+++ b/debian/python3-openvswitch.install
@@ -0,0 +1 @@
+usr/share/openvswitch/python/ovs usr/lib/python3.7/dist-packages/
diff --git a/debian/rules b/debian/rules
index 77f3a1984..4dc05c39b 100755
--- a/debian/rules
+++ b/debian/rules
@@ -22,7 +22,7 @@ PARALLEL =
 endif
 
 %:
-	dh $@ --with autoreconf,python2 --parallel
+	dh $@ --with autoreconf,python3 --parallel
 
 # use --as-needed only if supported by dh-autoreconf (to simplify backporting)
 DH_AS_NEEDED=$(shell dpkg --compare-versions $$(dpkg --status dh-autoreconf | grep Version | cut -d' ' -f2) ge 6 && echo --as-needed)