Switch to import hook from @minrk

scipy-notebook/Dockerfile

@@ -64,8 +64,8 @@ RUN ln -s $CONDA_DIR/envs/python2/bin/pip $CONDA_DIR/bin/pip2 && \
     ln -s $CONDA_DIR/bin/pip $CONDA_DIR/bin/pip3
 
 # Configure ipython kernel to use matplotlib inline backend by default
-RUN mkdir -p $HOME/.ipython/profile_default && \
-    echo "c.InteractiveShellApp.matplotlib = 'inline'" > $HOME/.ipython/profile_default/ipython_kernel_config.py
+RUN mkdir -p $HOME/.ipython/profile_default/startup
+COPY mplimporthook.py $HOME/.ipython/profile_default/startup/
 
 USER root
 

scipy-notebook/mplimporthook.py

+"""Startup script for IPython kernel.
+
+Installs an import hook to configure the matplotlib backend on the fly.
+
+Originally from @minrk at 
+https://github.com/minrk/profile_default/blob/master/startup/mplimporthook.py
+Repurposed for docker-stacks to address repeat bugs like
+https://github.com/jupyter/docker-stacks/issues/235.
+"""
+import sys
+from IPython import get_ipython
+
+class MatplotlibFinder(object):
+    """Import hook that notices when matplotlib.pyplot or pylab is imported
+    and tries to configure the matplotlib backend appropriately for the
+    environment.
+    """
+    _called = False
+    
+    def find_module(self, fullname, path=None):
+        if self._called:
+            # already handled
+            return
+        
+        if fullname not in ('pylab', 'matplotlib.pyplot'):
+            # not matplotlib
+            return
+        
+        # don't call me again
+        self._called = True
+        
+        try:
+            # remove myself from the import hooks
+            sys.meta_path = [loader for loader in sys.meta_path if loader is not self]
+        except ValueError:
+            pass
+        
+        ip = get_ipython()
+        if ip is None:
+            # not in an interactive environment
+            return
+            
+        if ip.pylab_gui_select:
+            # backend already selected
+            return
+            
+        if hasattr(ip, 'kernel'):
+            # default to inline in kernel environments
+            ip.enable_matplotlib('inline')
+        else:
+            print('enabling matplotlib')
+            ip.enable_matplotlib()
+
+# install the finder immediately
+sys.meta_path.insert(0, MatplotlibFinder())
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