Add a tool to generate the upper-constraints.txt file for publishing

Change-Id: I25a381e55362df0e7b31f18ff45c95ce3a28dc6a

tools/README.txt

@@ -51,6 +51,11 @@ integration.sh
 
 Used in the gate!  Install all the "$PROJECTS" to verify that g-r and the each project are compatible
 
+publish_constraints.sh
+----------------------
+Used in the gate!  Generate the constraints files from git for publishing to a
+static server.
+
 what-broke.py
 -------------
 figure out what requirements change likely broke us.

tools/publish_constraints.sh

@@ -0,0 +1,51 @@
+#!/usr/bin/env bash
+
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+function get_from_git()
+{
+    ref=$1
+    series=$2
+    path=${3:-publish/constraints/upper}
+
+    git show ${ref}:upper-constraints.txt > ${path}/${series}.txt
+}
+
+# Make the directory tree, don't fail if it already exists
+mkdir -p publish/constraints/upper
+# Clear out any stale files, don't fail if we just created it
+rm publish/constraints/upper/* || true
+
+case "$ZUUL_BRANCH" in
+stable/*)
+    series=$(basename "$ZUUL_BRANCH")
+    get_from_git origin/$ZUUL_BRANCH $series
+;;
+master)
+    # NOTE(tonyb): Publish EOL'd constraints files.  We do this here as a 
+    # quick way to publish the data.  It can be removed anytime after the first
+    # successful run
+    for tag in juno-eol kilo-eol liberty-eol mitaka-eol ; do
+        # trim the '-eol'
+        series=${tag::-4}
+        get_from_git $tag $series
+    done
+
+    for series in queens rocky ; do
+        if ! git rev-parse origin/stable/$series ; then
+            get_from_git origin/master $series
+        fi
+    done
+    get_from_git origin/master master
+;;
+esac