Merge pull request #11 from JaviMerino/ipynb_exp_improvs

Generic Ipynb_exporter improvements to ease ipython 3 support

wlauto/utils/ipython.py

@@ -0,0 +1,129 @@
+#    Copyright 2015 ARM Limited
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+import os
+import subprocess
+
+import_error_str = ''
+try:
+    import IPython
+except ImportError as import_error:
+    IPython = None
+    # Importing IPython can fail for a variety of reasons, report the actual
+    # failure unless it's just that the package is not present
+    if import_error.message.startswith("No module named"):  # pylint: disable=E1101
+        import_error_str = 'ipynb_exporter requires ipython package to be installed'
+    else:
+        import_error_str = import_error.message
+
+if IPython and (IPython.version_info[0] == 2):
+    import IPython.kernel
+    import IPython.nbformat.v3
+
+    def read_notebook(notebook_in):
+        return IPython.nbformat.v3.reads_json(notebook_in)
+
+    def write_notebook(notebook, fout):
+        IPython.nbformat.v3.nbjson.JSONWriter().write(notebook, fout)
+
+    NotebookNode = IPython.nbformat.v3.NotebookNode
+
+    IPYTHON_NBCONVERT = ['ipython', 'nbconvert', '--to=latex', '--post=PDF']
+
+elif IPython:
+    # Unsupported IPython version
+    IPython_ver_str = ".".join([str(n) for n in IPython.version_info])
+    import_error_str = 'Unsupported IPython version {}'.format(IPython_ver_str)
+
+
+def run_cell(kernel_client, cell):
+    """Run a cell of a notebook in an ipython kernel and return its output"""
+    kernel_client.execute(cell.input)
+
+    outs = []
+    while True:
+        msg = kernel_client.get_iopub_msg()
+
+        msg_type = msg["msg_type"]
+        content = msg["content"]
+        out = NotebookNode(output_type=msg_type)
+
+        if msg_type == "status":
+            if content["execution_state"] == "idle":
+                break
+            else:
+                continue
+        elif msg_type == "pyin":
+            continue
+        elif msg_type == "stream":
+            out.stream = content["name"]
+            out.text = content["data"]
+        elif msg_type in ("display_data", "pyout"):
+            for mime, data in content["data"].iteritems():
+                if mime == "text/plain":
+                    attr = "text"
+                else:
+                    attr = mime.split("/")[-1]
+                setattr(out, attr, data)
+        elif msg_type == "pyerr":
+            out.ename = content["ename"]
+            out.evalue = content["evalue"]
+            out.traceback = content["traceback"]
+        else:
+            raise ValueError("Unknown msg_type {}".format(msg_type))
+
+        outs.append(out)
+
+    return outs
+
+
+def run_notebook(notebook):
+    """Run the notebook"""
+
+    kernel_manager = IPython.kernel.KernelManager()
+    kernel_manager.start_kernel(stderr=open(os.devnull, 'w'))
+    kernel_client = kernel_manager.client()
+    kernel_client.start_channels()
+
+    for sheet in notebook.worksheets:
+        for (prompt_number, cell) in enumerate(sheet.cells, 1):
+            if cell.cell_type != "code":
+                continue
+
+            cell.outputs = run_cell(kernel_client, cell)
+
+            cell.prompt_number = prompt_number
+            if cell.outputs:
+                cell.outputs[0]["prompt_number"] = prompt_number
+
+    kernel_manager.shutdown_kernel()
+
+
+def generate_pdf(nbbasename, output_directory):
+    """Generate a PDF from the ipython notebook
+
+    ipython nbconvert claims that the CLI is not stable, so keep this
+    function here to be able to cope with inconsistencies
+
+    """
+
+    prev_dir = os.getcwd()
+    os.chdir(output_directory)
+
+    with open(os.devnull, 'w') as devnull:
+        subprocess.check_call(IPYTHON_NBCONVERT + [nbbasename], stderr=devnull)
+
+    os.chdir(prev_dir)
+