Usage with Python projects

After installing Raster Loader, you can use it in your Python project.

First, import the corresponding connection class from the raster_loader package. For Snowflake, use SnowflakeConnection:

from raster_loader import SnowflakeConnection

For BigQuery, use BigQueryConnection:

from raster_loader import BigQueryConnection

Then, create a connection object with the appropriate parameters.

For Snowflake:

connection = SnowflakeConnection('my-user', 'my-password', 'my-account', 'my-database', 'my-schema')

For BigQuery:

connection = BigQueryConnection('my-project')

Note

Accessing BigQuery with Raster Loader requires the GOOGLE_APPLICATION_CREDENTIALS environment variable to be set to the path of a JSON file containing your BigQuery credentials. See the GCP documentation for more information.

Uploading a raster file to BigQuery

To upload a raster file, use the upload_raster function

For example:

connector.upload_raster(
    file_path = 'path/to/raster.tif',
    fqn = 'database.schema.tablename',
)

This function returns True if the upload was successful.

The input raster must be a GoogleMapsCompatible raster. You can make your raster compatible by converting it with the following GDAL command:

gdalwarp -of COG -co TILING_SCHEME=GoogleMapsCompatible -co COMPRESS=DEFLATE -co OVERVIEWS=NONE -co ADD_ALPHA=NO -co RESAMPLING=NEAREST -co BLOCKSIZE=512 <input_raster>.tif <output_raster>.tif

Inspecting a raster file

You can also access and inspect a raster file located in a BigQuery or Snowflake table using the get_records() function.

For example:

records = connector.get_records(
    fqn = 'database.schema.tablename',
)

This function returns a DataFrame with some samples from the raster table on BigQuery (10 rows by default).