aws-lambda-docker-rasterio

AWS Lambda Container Image with Python Rasterio for querying Cloud Optimised GeoTiffs.

This repository contains an example AWS Lambda Docker image which uses Rasterio to query pixel values from a Cloud Optimised GeoTIFF (COG) stored in an S3 bucket. You can test the function locally using the Lambda Runtime Interface Emulator.

Table of Contents

• Background
• Install
• Usage
• API
• Deploy
• Maintainers
• Contributing
• License

Background

Previously Addresscloud built stripped-down Python packages to include Rasterio in AWS Lambda functions, using a script developed by Mapbox (see: https://github.com/mapbox/aws-lambda-python-packages). At re:Invent 2020 AWS launched support for custom container images to be executed as Lambda functions (see: https://aws.amazon.com/blogs/aws/new-for-aws-lambda-container-image-support/), making the use of Rasterio inside AWs Lambda's much easier and more accessible.

Install

# Build the Docker image locally
docker build -t rasterio .

Usage

The handler function reads the pixel values from a COG within a specificed polygon.

The Docker container includes the Lambda Runtime Interface Emulator so you can test the functions by running the images with Docker locally:

docker run -p 9000:8080 -e AWS_ACCESS_KEY_ID=$AWS_ACCESS_KEY_ID -e AWS_SECRET_ACCESS_KEY=$AWS_SECRET_ACCESS_KEY rasterio:latest

Then in a separate terminal you can make calls to the service, specifying the raster file and area to query:

curl -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations"\
    -d '{
            "raster": "s3://copernicus-dem-30m/Copernicus_DSM_COG_10_N55_00_W006_00_DEM/Copernicus_DSM_COG_10_N55_00_W006_00_DEM.tif",
            "geom": [
                {
                "type": "Polygon",
                "coordinates": [[[-5.2857375145,55.7018595345],[-5.2792572975,55.7018595345],[-5.2792572975,55.7052207941],[-5.2857375145,55.7052207941],[-5.2857375145,55.7018595345]]]
                }
            ]
        }'

This example queries elevation values from the Copernicus DEM.

API

main

Returns pixels values within specified area.

Requires the following parameters:

• raster: S3 address of the COG to query
• geom: JSON/Fiona polygon geometry object

Example query:

{
  "raster": "s3://copernicus-dem-30m/Copernicus_DSM_COG_10_N55_00_W006_00_DEM/Copernicus_DSM_COG_10_N55_00_W006_00_DEM.tif",
    "geom": [
    {
      "type": "Polygon",
      "coordinates": [
        [
          [
            -5.2857375145,
            55.7018595345
          ],
          [
            -5.2792572975,
            55.7018595345
          ],
          [
            -5.2792572975,
            55.7052207941
          ],
          [
            -5.2857375145,
            55.7052207941
          ],
          [
            -5.2857375145,
            55.7018595345
          ]
        ]
      ]
    }
  ]
}

Example response:

"[[[0.0, 0.0, 0.0, 0.4298372268676758, 3.1277780532836914, 3.167654514312744, 3.940603017807007, 8.856860160827637, 14.149166107177734, 19.369218826293945, 21.710126876831055, 28.996673583984375, 34.88554763793945, 41.25983428955078, 48.78239822387695, 56.83858108520508, 65.9479751586914], ...]]"

Deploy

1. Build Docker image locally
2. Push to Docker repository (AWS ECR Repository)
3. Create Lambda using container image

See this tutorial for more details: https://aws.amazon.com/blogs/aws/new-for-aws-lambda-container-image-support/

Maintainers

@tomasholderness

Contributing

PRs accepted.

Small note: If editing the README, please conform to the standard-readme specification.

License

MIT © 2021 Addresscloud Limited