Fix requirements for influxdb and cassandra

Both are optional requirements (but one must be used) so add both to the
"extras" section instead of a commented entry in requirements.txt .

Change-Id: I1f0eca2474ca275f64314a7b30b18e534afefdee

requirements.txt

@@ -5,6 +5,4 @@ oslo.config>=3.22.0 # Apache-2.0
 oslo.log>=3.22.0 # Apache-2.0
 
 six>=1.9.0 # MIT
-#influxdb==2.8.0
-#cassandra-driver>=2.1.4,!=3.6.0 # Apache-2.0
 monasca-common>=1.4.0 # Apache-2.0

setup.cfg

@@ -28,6 +28,12 @@ data_files =
         etc/monasca/persister.conf
         etc/monasca/persister-logging.conf
 
+[extras]
+influxdb =
+    influxdb>=2.9.2  # MIT
+cassandra =
+    cassandra-driver>=2.1.4,!=3.6.0 # Apache-2.0
+
 [pbr]
 autodoc_index_modules = True
 

tox.ini

@@ -20,7 +20,8 @@ whitelist_externals = bash
                       rm
 install_command =
     {toxinidir}/tools/tox_install.sh {env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
-deps = -r{toxinidir}/requirements.txt
+deps = .[influxdb,cassandra]
+       -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands =
   find {toxinidir} -type f -name "*.py[c|o]" -delete