diff --git a/AUTHORS b/AUTHORS
index 2011969df..5017fd07f 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -11,6 +11,7 @@ Bertrand Lallau <bertrand.lallau@thalesgroup.com>
 Boris Bobrov <bbobrov@suse.com>
 Brad Klein <bradley.klein@twcable.com>
 Cao Xuan Hoang <hoangcx@vn.fujitsu.com>
+Chandan Kumar <chkumar@redhat.com>
 Christoph Held <christoph.held@est.fujitsu.com>
 Clenimar Filemon <clenimar.filemon@gmail.com>
 Craig Bryant <craig.bryant@hp.com>
@@ -27,6 +28,7 @@ Derrick Johnson <johnson.derrick@gmail.com>
 Dexter Fryar <dexter.fryar@outlook.com>
 Dirk Mueller <dirk@dmllr.de>
 Dobroslaw Zybort <dobroslaw.zybort@ts.fujitsu.com>
+Doug Hellmann <doug@doughellmann.com>
 Emma Foley <emma.l.foley@intel.com>
 Erickson Santos <erickson@lsd.ufcg.edu.br>
 Flavio Percoco <flaper87@gmail.com>
@@ -59,6 +61,7 @@ Matteus Silva <silvamatteus@lsd.ufcg.edu.br>
 Michael Bielinski <michael.bielinski@hp.com>
 Michael James Hoppal <michael.jam.hoppal@hp.com>
 Michal Zielonka <michal.zielonka@ts.fujitsu.com>
+Monasca CI <aadams@hpe.com>
 Monty Taylor <mordred@inaugust.com>
 Nam Nguyen Hoai <namnh@vn.fujitsu.com>
 OpenStack Release Bot <infra-root@openstack.org>
@@ -90,6 +93,7 @@ ZhiQiang Fan <aji.zqfan@gmail.com>
 Zuul <zuul@review.openstack.org>
 alpineriveredge <alpineriveredge@gmail.com>
 anilkumarthovi <anilkumar.thovi@cognizant.com>
+bandorf <matthias.bandorf@est.fujitsu.com>
 bklei <bradley.klein@twcable.com>
 cindy oneill <cindy.o-neill@hp.com>
 dieterly <deklan.dieterly@hpe.com>
@@ -112,3 +116,4 @@ raymondr <raymondr@users.noreply.github.com>
 roland-hochmuth <roland.hochmuth@hpe.com>
 satsuki_fukazu <fukazu.satsuki@po.ntts.co.jp>
 venkatamahesh <venkatamaheshkotha@gmail.com>
+wangqi <wang.qi@99cloud.net>
diff --git a/lower-constraints.txt b/lower-constraints.txt
index 744263f6e..7245e5e6c 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -5,7 +5,7 @@ asn1crypto==0.23.0
 Babel==2.3.4
 bandit==1.4.0
 bashate==0.5.1
-cassandra-driver==2.1.4
+cassandra-driver==3.3.0
 cffi==1.7.0
 chardet==3.0.4
 cliff==2.8.0
diff --git a/setup.cfg b/setup.cfg
index 34bdb9f32..61a1bc53f 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -26,6 +26,12 @@ data_files =
         etc/api-logging.conf
         etc/api-config.ini
 
+[extras]
+influxdb =
+  influxdb>=2.9.2 # MIT
+cassandra =
+  cassandra-driver!=3.6.0,>=3.3.0 # Apache-2.0
+
 [entry_points]
 console_scripts =
     monasca-api = monasca_api.api.server:launch
diff --git a/test-requirements.txt b/test-requirements.txt
index d5ba2456d..69ca844eb 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -7,7 +7,7 @@ bashate>=0.5.1 # Apache-2.0
 hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
 Babel!=2.4.0,>=2.3.4 # BSD
 coverage!=4.4,>=4.0 # Apache-2.0
-cassandra-driver!=3.6.0,>=2.1.4 # Apache-2.0
+cassandra-driver!=3.6.0,>=3.3.0 # Apache-2.0
 fixtures>=3.0.0 # Apache-2.0/BSD
 httplib2>=0.9.1 # MIT
 influxdb>=2.9.2 # MIT
diff --git a/tox.ini b/tox.ini
index 07612a577..28e761c74 100644
--- a/tox.ini
+++ b/tox.ini
@@ -15,42 +15,30 @@ deps =
   -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
   -r{toxinidir}/test-requirements.txt
   -r{toxinidir}/requirements.txt
+  .[influxdb,cassandra]
 whitelist_externals = bash
                       find
                       rm
 commands =
   find . -type f -name "*.pyc" -delete
-
-[testenv:py27]
-basepython = python2.7
-commands =
-  {[testenv]commands}
-  ostestr {posargs}
-
-[testenv:py35]
-basepython = python3.5
-commands =
-  {[testenv]commands}
   ostestr {posargs}
 
 [testenv:cover]
 basepython = python2.7
 commands =
-  {[testenv]commands}
   coverage erase
-  python setup.py test --coverage --testr-args='{posargs}' --coverage-package-name=monasca_api --omit=monasca_api/hacking/*
+  python setup.py test --coverage --testr-args='{posargs}' \
+    --coverage-package-name=monasca_api --omit=monasca_api/hacking/*
   coverage report
 
 [testenv:debug]
 commands =
-  {[testenv]commands}
   oslo_debug_helper -t ./monasca_api/tests {posargs}
 
 [testenv:flake8]
 skip_install = True
 usedevelop = False
 commands =
-  {[testenv]commands}
   flake8 monasca_api
 
 [testenv:bandit]
@@ -84,13 +72,15 @@ description = Called from CI scripts to test and publish the API Ref
 commands =
   rm -rf api-ref/build
   {[testenv:checkjson]commands}
-  sphinx-build -W -b html -d api-ref/build/doctrees api-ref/source api-ref/build/html
+  sphinx-build -W -b html -d api-ref/build/doctrees \
+    api-ref/source api-ref/build/html
 
 [testenv:releasenotes]
 description = Called from CI script to test and publish the Release Notes
 commands =
   rm -rf releasenotes/build
-  sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
+  sphinx-build -a -E -W -d releasenotes/build/doctrees -b html \
+    releasenotes/source releasenotes/build/html
 
 [testenv:devdocs]
 description = Builds developer documentation
@@ -120,7 +110,8 @@ whitelist_externals =
   bash
 commands =
   bash -c "! find doc/ -type f -name *.json | xargs grep -U -n $'\r'"
-  bash -c '! find doc/ -type f -name *.json | xargs -t -n1 python -m json.tool 2>&1 > /dev/null | grep -B1 -v ^python'
+  bash -c '! find doc/ -type f -name *.json | \
+    xargs -t -n1 python -m json.tool 2>&1 > /dev/null | grep -B1 -v ^python'
 
 [testenv:genconfig]
 description = Generates sample configuration file for monasca-api
@@ -156,8 +147,9 @@ import_exceptions =
   six.moves
 
 [testenv:lower-constraints]
-basepython = python3
+basepython = python2
 deps =
   -c{toxinidir}/lower-constraints.txt
   -r{toxinidir}/test-requirements.txt
   -r{toxinidir}/requirements.txt
+  .[influxdb,cassandra]