Zarr over http

zarr_over_http.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Open Zarr over HTTP using fsspec"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<xarray.Dataset>\n",
       "Dimensions:  (x: 20, y: 10)\n",
       "Coordinates:\n",
       "  * x        (x) int64 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19\n",
       "  * y        (y) int64 0 1 2 3 4 5 6 7 8 9\n",
       "Data variables:\n",
       "    foo      (y, x) float64 1.0 1.0 1.0 1.0 1.0 1.0 ... 1.0 1.0 1.0 1.0 1.0 1.0"
      ]
     },
     "execution_count": 1,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# create test data\n",
    "import xarray as xr\n",
    "import numpy as np\n",
    "ds = xr.DataArray(np.ones((10, 20)), dims=['y', 'x'],\n",
    "                  coords={'x': np.arange(20),\n",
    "                          'y': np.arange(10)},\n",
    "                  attrs={'standards': 'None whatsover'},\n",
    "                  name='foo').to_dataset()\n",
    "ds"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<xarray.backends.zarr.ZarrStore at 0x11c5c1198>"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# export to zarr directory store\n",
    "ds.to_zarr('test_remote.zarr', mode='w', consolidated=True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<subprocess.Popen at 0x11c692780>"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# spawn a web server in the background to serve the data\n",
    "import subprocess\n",
    "subprocess.Popen([\"python\", \"-m\", \"http.server\", \"9999\"])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<xarray.Dataset>\n",
       "Dimensions:  (x: 20, y: 10)\n",
       "Coordinates:\n",
       "  * x        (x) int64 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19\n",
       "  * y        (y) int64 0 1 2 3 4 5 6 7 8 9\n",
       "Data variables:\n",
       "    foo      (y, x) float64 dask.array<shape=(10, 20), chunksize=(10, 20)>"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# reopen it\n",
    "from fsspec.implementations.http import HTTPFileSystem\n",
    "fs = HTTPFileSystem()\n",
    "http_map = fs.get_mapper('http://0.0.0.0:9999/test_remote.zarr')\n",
    "ds_remote = xr.open_zarr(http_map, consolidated=True)\n",
    "ds_remote"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<xarray.Dataset>\n",
       "Dimensions:  ()\n",
       "Data variables:\n",
       "    foo      float64 1.0"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# compute stuff\n",
    "ds_remote.mean().load()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
 ],
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