Do not make matplotlib mandatory

hpcbench/cli/__init__.py

@@ -3,7 +3,6 @@
 import logging
 
 from docopt import docopt
-import matplotlib
 
 from hpcbench import __version__
 from hpcbench.toolbox.loader import load_components
@@ -27,5 +26,10 @@ def cli_common(doc, **kwargs):
     arguments = docopt(doc, version='hpcbench ' + __version__, **kwargs)
     setup_logger(arguments['-v'])
     load_components()
-    matplotlib.use('PS')
+    try:
+        import matplotlib
+    except ImportError:
+        pass
+    else:
+        matplotlib.use('PS')
     return arguments

setup.py

@@ -44,17 +44,19 @@
         'cached-property==1.3.0',
         'docopt==0.6.2',
         'elasticsearch==5.4.0',
-        'matplotlib==2.0.2',
         'packaging==16.8',
         'PyYAML>=3.12',
         'six==1.10',
     ],
+    extras_require=dict(
+      PLOTTING=['matplotlib==2.0.2'],
+    ),
     entry_points="""
         [console_scripts]
         ben-doc = hpcbench.cli.bendoc:main
         ben-elk = hpcbench.cli.benelk:main
         ben-et = hpcbench.cli.benet:main
-        ben-plot = hpcbench.cli.benplot:main
+        ben-plot = hpcbench.cli.benplot:main [PLOTTING]
         ben-sh = hpcbench.cli.bensh:main
         ben-umb = hpcbench.cli.benumb:main
         [hpcbench.benchmarks]

tox.ini

@@ -8,7 +8,7 @@ passenv =
   UT_SKIP_ELASTICSEARCH
   LD_LIBRARY_PATH
 commands =
-	pip install -e .
+	pip install -e .[PLOTTING]
     python setup.py nosetests --with-coverage --cover-inclusive --cover-erase {posargs}
     flake8 hpcbench
     -pylint hpcbench