Add Constraints support

Adding constraints support to clients is slightly more complex than
services as the clients themselves are listed in upper-constraints.txt
which leads to errors that you can't install a specific version and a
constrained version.

This change adds constraints support by also adding a helper script to
edit the constraints to remove monasca-agent. It also uncaps psutil
which is a temporary workaround for monasca-agent until it is uncapped
globally.

Change-Id: Ib56d758e1b6fd6200eace660fc123f147dbdea18

tools/tox_install.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+
+# Client constraint file contains this client version pin that is in conflict
+# with installing the client from source. We should remove the version pin in
+# the constraints file before applying it for from-source installation.
+
+CONSTRAINTS_FILE="$1"
+shift 1
+
+set -e
+
+# NOTE(tonyb): Place this in the tox enviroment's log dir so it will get
+# published to logs.openstack.org for easy debugging.
+localfile="$VIRTUAL_ENV/log/upper-constraints.txt"
+
+if [[ "$CONSTRAINTS_FILE" != http* ]]; then
+    CONSTRAINTS_FILE="file://$CONSTRAINTS_FILE"
+fi
+# NOTE(tonyb): need to add curl to bindep.txt if the project supports bindep
+curl "$CONSTRAINTS_FILE" --insecure --progress-bar --output "$localfile"
+
+pip install -c"$localfile" openstack-requirements
+
+# This is the main purpose of the script: Allow local installation of
+# the current repo. It is listed in constraints file and thus any
+# install will be constrained and we need to unconstrain it.
+
+# NOTE(dmllr): temporary local uncaping of psutil in upper-constraints
+# if it is still 1.x. Remove me when https://review.openstack.org/#/c/333717/
+# merges
+edit-constraints "$localfile" -- "$CLIENT_NAME" psutil===3.0.1
+
+pip install -c"$localfile" -U "$@"
+exit $?

tox.ini

@@ -5,14 +5,15 @@ skipsdist = True
 
 [testenv]
 usedevelop = True
-install_command = pip install -U {opts} {packages}
 setenv =
     VIRTUAL_ENV={envdir}
     DISCOVER_DIRECTORY=tests
+    CLIENT_NAME=monasca-agent
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 whitelist_externals = bash
                       find
+install_command = {toxinidir}/tools/tox_install.sh {env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
 commands =
   find . -type f -name "*.pyc" -delete
   nosetests tests/ --verbose