84 lines
2.4 KiB
Text
84 lines
2.4 KiB
Text
{
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"cells": [
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"# Ensure notebooks can execute in parallel\n",
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"\n",
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"This notebook uses a file system based \"lock\" to assert that two instances of the notebook kernel will run in parallel. Each instance writes to a file in a temporary directory, and then tries to read the other file from\n",
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"the temporary directory, so that running them in sequence will fail, but running them in parallel will succed.\n",
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"\n",
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"Two notebooks are launched, each which sets the `this_notebook` variable. One notebook is set to `this_notebook = 'A'` and the other `this_notebook = 'B'`."
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"import os\n",
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"import os.path\n",
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"import tempfile\n",
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"import time"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"# the variable this_notebook is injectected in a cell above by the test framework.\n",
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"this_notebook = 'A'\n",
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"other_notebook = 'B'\n",
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"directory = os.environ['NBEXECUTE_TEST_PARALLEL_TMPDIR']\n",
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"with open(os.path.join(directory, 'test_file_{}.txt'.format(this_notebook)), 'w') as f:\n",
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" f.write('Hello from {}'.format(this_notebook))"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"start = time.time()\n",
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"timeout = 5\n",
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"end = start + timeout\n",
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"target_file = os.path.join(directory, 'test_file_{}.txt'.format(other_notebook))\n",
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"while time.time() < end:\n",
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" time.sleep(0.1)\n",
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" if os.path.exists(target_file):\n",
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" with open(target_file, 'r') as f:\n",
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" text = f.read()\n",
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" if text == 'Hello from {}'.format(other_notebook):\n",
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" break\n",
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"else:\n",
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" assert False, \"Timed out – didn't get a message from {}\".format(other_notebook)"
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]
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}
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],
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"metadata": {
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"kernelspec": {
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"display_name": "Python 3",
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"language": "python",
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"name": "python3"
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},
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"language_info": {
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"codemirror_mode": {
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"name": "ipython",
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"version": 3
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},
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"file_extension": ".py",
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"mimetype": "text/x-python",
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"name": "python",
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"nbconvert_exporter": "python",
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"pygments_lexer": "ipython3",
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"version": "3.6.7"
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}
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},
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"nbformat": 4,
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"nbformat_minor": 2
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}
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