manage_env_variable_in_jupyter_ipython.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 1 - Create a pre run file\n",
    "+ Run this section **only once to create/modify the file pre_run.py**\n",
    "+ This file is located in the IPython local config folder\n",
    "+ It contains Python instructions\n",
    "+ It is executed upon IPython kernel launch - before the notebook opens"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'/Users/Olivier/.ipython'"
      ]
     },
     "execution_count": 1,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data = !ipython locate\n",
    "dir_ipython = data[0]\n",
    "dir_ipython"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'/Users/Olivier/.ipython/profile_default/startup/pre_run.py'"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "file_prerun = dir_ipython + '/profile_default/startup/pre_run.py'\n",
    "file_prerun"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Overwriting /Users/Olivier/.ipython/profile_default/startup/pre_run.py\n"
     ]
    }
   ],
   "source": [
    "%%writefile {file_prerun}\n",
    "\n",
    "toto = 22\n",
    "\n",
    "import pandas as pd\n",
    "\n",
    "import os\n",
    "os.environ['myvar'] = 'myvarvalue'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "\r\n",
      "toto = 22\r\n",
      "\r\n",
      "import pandas as pd\r\n",
      "\r\n",
      "import os\r\n",
      "os.environ['myvar'] = 'myvarvalue'"
     ]
    }
   ],
   "source": [
    "!cat {file_prerun}"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 2 - Test pre run file exec\n",
    "+ Run this section **right after opening notebook**\n",
    "+ To check the impact of pre_run.py on kernel state\n",
    "+ You can see that\n",
    "    + modules were imported\n",
    "    + variables initialized\n",
    "    + environment variables set"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "22"
      ]
     },
     "execution_count": 1,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "toto"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'0.20.3'"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pd.__version__"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'myvarvalue'"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "os.environ.get('myvar')"
   ]
  }
 ],
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  "kernelspec": {
   "display_name": "Python 3",
   "language": "python",
   "name": "python3"
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  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
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   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
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