PyDrive Support

As demonstrated in the example notebook, zonal statistics can be submitted as tasks using Earth Engine's ee.batch.Export.table.toDrive feature. This is generally preferred when running large computations, or trying to batch several tasks in parallel.

The ZonalStats object contains a function getZonalStats() to retrieve the resulting table directly from Google Drive using pydrive.

This requires additional configuration to provide access to Google Drive. First, the pydrive package needs to be installed.

pip install pydrive

Setup

Follow the instructions to obtain a client configuration file client_secrets.json.

One additional step required is go to Audience and add your email as a test user. Otherwise, you will have to publish the application.

Place the client_secrets.json file in a folder such that the authenticateGoogleDrive() function can find it. By default the function looks for the file in ~/.config/creds/client_secrets.json. You can change this by passing the creds_dir argument to the function.

Usage

from gee_zonal import authenticateGoogleDrive
from os.path.import join

# Authorize Google Drive
drive = authenticateGoogleDrive(creds_dir = join(expanduser('~'), '.config', 'creds')) # Change to path where you stored client_secrets file

# Run ZonalStats
zs = ZonalStats(
    collection_id='UCSB-CHG/CHIRPS/PENTAD',
    target_features=AOIs,
    statistic_type="mean",
    temporal_stat="sum",
    frequency="annual",
    scale=5000,
    output_dir = "gdrive_folder",
    output_name="pretty_output"
)

# Submit task to Earth Engine
zs.runZonalStats()

# Check if task is completed
zs.reportRunTime()

# Retrieve result
df = zs.getZonalStats(drive)