{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Jinja templates"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from jinja2 import Template "
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Jinja\n",
    "\n",
    "https://jinja.palletsprojects.com/en/2.11.x/\n",
    "\n",
    "> Jinja is a modern and designer-friendly templating language for Python (...). It is fast, widely used and secure with the optional sandboxed template execution environment:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Basic usage of Jinja\n",
    "template = Template('Hello {{ name }}!')\n",
    "you = 'XPUB1'\n",
    "output = template.render(name=you)\n",
    "print(output)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Jinja is very useful for generating HTML pages\n",
    "# Let's start with a HTML snippet: \n",
    "template = Template('<h1>Hello {{ name }}!</h1>')\n",
    "you = 'XPUB1'\n",
    "html = template.render(name=you)\n",
    "print(html)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# But these templates can be much longer.\n",
    "# Let's now use a separate jinja-template.html file, as our template:\n",
    "template_file = open('jinja-template.html').read()\n",
    "template = Template(template_file)\n",
    "you = 'XPUB1'\n",
    "html = template.render(name=you)\n",
    "print(html)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## For loops & if / else"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### For loops\n",
    "\n",
    "For loops are written in a *pythonic* way.\n",
    "\n",
    "What is different, is the \"closing tag\" `{% endfor %}`.\n",
    "\n",
    "```\n",
    "{% for item in list %}\n",
    "    \n",
    "    {{ item }}\n",
    "    \n",
    "{% endfor %}\n",
    "```\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "template = Template('''\n",
    "\n",
    "<h1>Hello to</h1>\n",
    "\n",
    "{% for name in XPUB1 %}\n",
    "\n",
    "    <h2>{{ name  }}<h2>\n",
    "\n",
    "{% endfor %}\n",
    "\n",
    "''')\n",
    "XPUB1 = ['you', 'you', 'you']\n",
    "html = template.render(XPUB1=XPUB1)\n",
    "print(html)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Or display it in HTML here in the notebook directly :)\n",
    "from IPython.core.display import HTML\n",
    "HTML(html)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### if / else\n",
    "\n",
    "Also if / else statements are written in a *pythonic* way.\n",
    "\n",
    "The only thing again that is new, is the \"closing tag\" `{% endif %}`.\n",
    "\n",
    "```\n",
    "{% for item in list %}\n",
    "    \n",
    "    {% if 'hello' in item %}\n",
    "\n",
    "        <h1>HELLO</h1>\n",
    "    \n",
    "    {% else %}\n",
    "    \n",
    "        {{ item }}\n",
    "    \n",
    "    {% endif %}\n",
    "    \n",
    "{% endfor %}\n",
    "```"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "template = Template('''\n",
    "\n",
    "<h1>Hello to</h1>\n",
    "\n",
    "{% for name in XPUB1 %}\n",
    "\n",
    "    {% if name == 'me' %}\n",
    "\n",
    "        <h2 style=\"color:magenta;\">{{ name  }}<h2>\n",
    "    \n",
    "    {% else %}\n",
    "\n",
    "        <h2>{{ name  }}<h2>\n",
    "        \n",
    "    {% endif %}\n",
    "\n",
    "{% endfor %}\n",
    "\n",
    "''')\n",
    "XPUB1 = ['you', 'me', 'you']\n",
    "html = template.render(XPUB1=XPUB1)\n",
    "HTML(html)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Further diving\n",
    "\n",
    "More syntax details can be found here: https://jinja.palletsprojects.com/en/2.11.x/templates/"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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