Added docker and first exercise

nb_strip_output.py

@@ -0,0 +1,110 @@
+#! /usr/bin/env python3
+"""
+ strip output of IPython Notebooks
+ add this as `.git/hooks/pre-commit`
+ to run every time you commit a notebook
+
+strip outputs from an IPython Notebook Opens a notebook, strips its output, and
+writes the outputless version to the original file.  Useful mainly as a git
+filter or pre-commit hook for users who don't want to track output in VCS.
+This does mostly the same thing as the `Clear All Output` command in the
+notebook UI.
+LICENSE: Public Domain
+Adapted from: https://gist.github.com/minrk/6176788
+"""
+
+import subprocess
+from subprocess import PIPE, Popen
+import io
+import argparse
+import os
+
+try:
+    # Jupyter >= 4
+    from nbformat import read, write, NO_CONVERT
+except ImportError:
+    # IPython 3
+    try:
+        from IPython.nbformat import read, write, NO_CONVERT
+    except ImportError:
+        # IPython < 3
+        from IPython.nbformat import current
+
+        def read(f, as_version):
+            return current.read(f, 'json')
+
+        def write(nb, f):
+            return current.write(nb, f, 'json')
+
+
+def get_rev():
+    command = "git rev-parse --verify HEAD".split(" ")
+    if subprocess.call(command, stdin=PIPE, stdout=PIPE, stderr=PIPE) == 0:
+        return 'HEAD'
+    else:
+        return '4b825dc642cb6eb9a060e54bf8d69288fbee4904'
+
+
+def get_notebooks(against):
+    command = "git diff-index -z --cached {} --name-only".format(against)
+    p = Popen(command.split(" "), stdin=PIPE, stdout=PIPE, stderr=PIPE)
+    output, err = p.communicate()
+    assert p.returncode == 0, \
+        "Command failed: {}\nstdout:\n{}\nstderr:\n{}"\
+            .format(command, output, err)
+    files = [binary_fname.decode('utf8')
+             for binary_fname in output.split(b'\x00')]
+    return set([f for f in files if f.endswith(".ipynb")])
+
+
+def run_as_git_hook():
+    against = get_rev()
+    for notebook_fname in get_notebooks(against):
+        print("Stripping output from: {}".format(notebook_fname))
+        strip_output(notebook_fname)
+
+    command = "git diff-index --check --cached {} --".format(against)
+    subprocess.call(command.split(" "))
+
+
+def _cells(nb):
+    """Yield all cells in an nbformat-insensitive manner"""
+    if nb.nbformat < 4:
+        for ws in nb.worksheets:
+            for cell in ws.cells:
+                yield cell
+    else:
+        for cell in nb.cells:
+            yield cell
+
+
+def strip_output(filename):
+    """strip the outputs from a notebook"""
+
+    with io.open(filename, 'r', encoding='utf8') as f:
+        nb = read(f, as_version=NO_CONVERT)
+
+    nb.metadata.pop('signature', None)
+    for cell in _cells(nb):
+        if 'outputs' in cell:
+            cell['outputs'] = []
+        if 'prompt_number' in cell:
+            cell['prompt_number'] = None
+    with io.open(filename, 'w', encoding='utf8') as f:
+        write(nb, f)
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(
+        description='Strips the output from a notebook')
+    parser.add_argument('file', type=str, default='', nargs='?',
+                        help='remove the output from this notebook')
+    args = parser.parse_args()
+    if args.file == '':
+        run_as_git_hook()
+
+    else:
+        fname = args.file
+        if not os.path.exists(fname):
+            print("File {} does not exists.".format(fname))
+        strip_output(fname)