Merge branch 'httpbin-python3'

Another fix for httpbin installation in CI builds.

Closes https://github.com/wxWidgets/wxWidgets/pull/2307

appveyor.yml

@@ -31,6 +31,7 @@ skip_commits:
     - .travis.yml
     - build/tools/travis-ci.sh
     - build/tools/before_install.sh
+    - build/tools/httpbin.sh
 
 environment:
   matrix:

build/tools/httpbin.sh

@@ -17,26 +17,27 @@ httpbin_launch() {
 
     case "$dist_codename" in
         trusty)
-            # Current decorator (>= 5) is incompatible with Python 2 which we
+            # Python 2.7.6 is too old to support SNI and can't be used.
-            # still use in some builds, so explicitly use a version which
+            PY3=3
-            # is known to work. Just specifying "decorator==4.4.2" doesn't work
-            # neither for some reason ("no matching distribution found"), so
-            # use an explicit URL.
-            pip_decorator_arg='https://files.pythonhosted.org/packages/ed/1b/72a1821152d07cf1d8b6fce298aeb06a7eb90f4d6d41acec9861e7cc6df0/decorator-4.4.2-py2.py3-none-any.whl'
 
-            # We need to disable SSL certificate checking under Trusty because
+            # Current decorator (>= 5) is incompatible with Python 3.4 used
-            # Python version there is too old to support SNI.
+            # here, so explicitly use a version which is known to work.
-            pip_options='--trusted-host files.pythonhosted.org'
+            pip_decorator_arg='decorator==4.4.2'
             ;;
 
         macOS)
+            # We use Python 2 under macOS 10.11 which doesn't have Python 3,
+            # and decorator >= 5 is incompatible with it too.
             pip_decorator_arg='decorator==4.4.2'
             ;;
 
         *)
             # Elsewhere just use Python 3.
             PY3=3
+            ;;
+    esac
 
+    if [ "$PY3" = 3 ]; then
         # Ensure that we have at least some version of pip.
         if ! python3 -m pip; then
             sudo apt-get -q -o=Dpkg::Use-Pty=0 install python3-pip
@@ -47,14 +48,14 @@ httpbin_launch() {
         # than python3, so upgrade it to fix this.
         #
         # However don't upgrade to a version which is too new because then
-            # it may not support Python version that we actually have.
+        # it may not support Python version that we actually have (this one
-            python3 -m pip install --user --upgrade pip==20.0.1
+        # still works with 3.4, 20.0.1 is the last one to support 3.5).
-            ;;
+        python3 -m pip install --user --upgrade pip==19.1.1
-    esac
+    fi
 
     echo "Installing using `python$PY3 -m pip --version`"
 
-    python$PY3 -m pip install $pip_decorator_arg httpbin --user $pip_options
+    python$PY3 -m pip install $pip_decorator_arg httpbin --user
     python$PY3 -m httpbin.core 2>&1 >httpbin.log &
     WX_TEST_WEBREQUEST_URL="http://localhost:5000"