stac-check

stac-check

A linting and validation tool for STAC assets

The intent of this project is to provide a validation tool that also follows the official STAC Best Practices document

Table of Contents

• Documentation
• Installation
  • Pip
  • Docker
• Usage
  • CLI Usage
  • Configuration
  • Geometry Validation
  • Python API Usage
• Examples
  • Basic Validation
  • Recursive Validation
  • Asset Validation
  • Link and Asset Validation
  • Invalid STAC
  • Using HTTP Headers
  • STAC API Validation
• Development
• Sponsors and Supporters
• Contributing
  • How to Contribute
  • Development Guidelines
  • Reporting Issues
• License

Documentation

The documentation is hosted on GitHub Pages at stac-utils.github.io/stac-check.

Building Documentation Locally

To build the documentation locally:

# Install the package with documentation dependencies
pip install -e ".[docs]"

# Build the documentation
make docs

The built documentation will be available in the docs/_build/html directory.

Alternatively, you can build the documentation using Docker:

# Build the Docker image and documentation
make docker-docs

Installation

Pip

$ pip install stac-check

For local development:

$ pip install -e '.[dev]'

Docker

$ make build
$ make shell

Usage

CLI Usage

Usage: stac-check [OPTIONS] FILE

Options:
  --version                Show the version and exit.
  -l, --links              Validate links for format and response.
  -a, --assets             Validate assets for format and response.
  -m, --max-depth INTEGER  Maximum depth to traverse when recursing. Omit this
                           argument to get full recursion. Ignored if
                           `recursive == False`.
  -r, --recursive          Recursively validate all related stac objects.
  --no-assets-urls         Disables the opening of href links when validating assets
                           (enabled by default).
  --header KEY VALUE       HTTP header to include in the requests. Can be used
                           multiple times.
  --pydantic               Use stac-pydantic for enhanced validation with Pydantic models.
  --verbose                Show verbose error messages.
  -o, --output FILE        Save output to the specified file.
  --item-collection        Validate item collection response. Can be combined with
                           --pages. Defaults to one page.
  --collections            Validate collections endpoint response. Can be combined with
                           --pages. Defaults to one page.
  -p, --pages INTEGER      Maximum number of pages to validate via --item-collection
                           or --collections. Defaults to one page.
  --help                   Show this message and exit.

Configuration

stac-check uses a configuration file to control which validation checks are performed. By default, it uses the built-in configuration at stac_check/stac-check.config.yml. You can customize the validation behavior by creating your own configuration file.

The configuration file has three main sections:

• linting: Controls which general best practices checks are enabled
• geometry_validation: Controls geometry-specific validation checks [BETA]
• settings: Configures thresholds for certain checks

Here's an example of the configuration options:

linting:
  # Identifiers should consist of only lowercase characters, numbers, '_', and '-'
  searchable_identifiers: true
  # Item name '{self.object_id}' should not contain ':' or '/'
  percent_encoded: true
  # Item file names should match their ids
  item_id_file_name: true
  # Collections and catalogs should be named collection.json and catalog.json
  catalog_id_file_name: true
  # A STAC collection should contain a summaries field
  check_summaries: true
  # Datetime fields should not be set to null
  null_datetime: true
  # best practices - check unlocated items to make sure bbox field is not set
  check_unlocated: true
  # best practices - recommend items have a geometry
  check_geometry: true
  # check to see if there are too many links
  bloated_links: true
  # best practices - check for bloated metadata in properties
  bloated_metadata: true
  # best practices - ensure thumbnail is a small file size ["png", "jpeg", "jpg", "webp"]
  check_thumbnail: true
  # best practices - ensure that links in catalogs and collections include a title field
  links_title: true
  # best practices - ensure that links in catalogs and collections include self link
  links_self: true

geometry_validation:
  # Master switch to enable/disable all geometry validation checks
  enabled: true
  # check if geometry coordinates are potentially ordered incorrectly (longitude, latitude)
  geometry_coordinates_order: true
  # check if geometry coordinates contain definite errors (latitude > ±90°, longitude > ±180°)
  geometry_coordinates_definite_errors: true
  # check if bbox matches the bounds of the geometry
  bbox_geometry_match: true
  # check if a bbox that crosses the antimeridian is correctly formatted
  bbox_antimeridian: true

settings:
  # number of links before the bloated links warning is shown
  max_links: 20
  # number of properties before the bloated metadata warning is shown
  max_properties: 20

To use a custom configuration file, set the STAC_CHECK_CONFIG environment variable to the path of your configuration file:

export STAC_CHECK_CONFIG=/path/to/your/config.yml
stac-check sample_files/1.0.0/core-item.json

Geometry Validation

Geometry validation is a feature of stac-check that allows you to validate the geometry of your STAC items. This feature is enabled by default, but can be disabled by setting geometry_validation.enabled to false in your configuration file.

The geometry validation feature checks for the following:

• Geometry coordinates are potentially ordered incorrectly (longitude, latitude)
• Geometry coordinates contain definite errors (latitude > ±90°, longitude > ±180°)
• Bbox matches the bounds of the geometry
• Bbox that crosses the antimeridian is correctly formatted

You can customize the geometry validation behavior by setting the following options in your configuration file:

• geometry_validation.geometry_coordinates_order: Check if geometry coordinates are potentially ordered incorrectly (longitude, latitude)
• geometry_validation.geometry_coordinates_definite_errors: Check if geometry coordinates contain definite errors (latitude > ±90°, longitude > ±180°)
• geometry_validation.bbox_geometry_match: Check if bbox matches the bounds of the geometry
• geometry_validation.bbox_antimeridian: Check if a bbox that crosses the antimeridian is correctly formatted

Python API Usage

from stac_check.lint import Linter

linter = Linter('<json_path>')

for k, v in linter.create_best_practices_dict().items():
    print(k, ":", v)

Examples

Basic Validation

stac-check sample_files/0.9.0/landsat8-sample.json

stac-check: STAC spec validation and linting tool

Please upgrade from version 0.9.0 to version 1.1.0!

Validator: stac-validator 3.9.1

Valid ITEM: True

Schemas validated:
    https://cdn.staclint.com/v0.9.0/extension/eo.json
    https://cdn.staclint.com/v0.9.0/extension/view.json
    https://cdn.staclint.com/v0.9.0/item.json

STAC Best Practices:
    Item name 'LC81530252014153LGN00' should only contain Searchable identifiers
    Identifiers should consist of only lowercase characters, numbers, '_', and '-'
    https://github.com/radiantearth/stac-spec/blob/master/best-practices.md#searchable-identifiers

    Item file names should match their ids: 'landsat8-sample' not equal to 'LC81530252014153LGN00

    A link to 'self' in links is strongly recommended


This object has 4 links

Recursive Validation

stac-check https://raw.githubusercontent.com/stac-utils/pystac/main/tests/data-files/examples/0.9.0/collection-spec/examples/landsat-collection.json --recursive

stac-check: STAC spec validation and linting tool

Please upgrade from version 0.9.0 to version 1.1.0!

Validator: stac-validator 3.9.1


Recursive: Validate all assets in a collection or catalog
Max-depth = None
-------------------------
Asset 1 Validated: https://raw.githubusercontent.com/stac-utils/pystac/main/tests/data-files/examples/0.9.0/collection-spec/examples/landsat-collection.json

Valid COLLECTION: True

Schemas validated:
    https://cdn.staclint.com/v0.9.0/collection.json

STAC Best Practices:
    Object should be called 'collection.json' not 'landsat-collection.json'

    A STAC collection should contain a summaries field
    It is recommended to store information like eo:bands in summaries

    Links in catalogs and collections should always have a 'title' field

This object has 4 links

-------------------------
Asset 2 Validated: https://landsat-stac.s3.amazonaws.com/landsat-8-l1/paths/catalog.json

Valid: False
Schemas validated:
    https://cdn.staclint.com/v0.9.0/collection.json
Error Type: JSONDecodeError
Error Message: Expecting value: line 1 column 1 (char 0)
-------------------------

Asset Validation

stac-check sample_files/1.0.0/core-item.json --assets

stac-check: STAC spec validation and linting tool

Please upgrade from version 1.0.0 to version 1.1.0!

Validator: stac-validator 3.9.1

Valid ITEM: True

Schemas validated:
    https://schemas.stacspec.org/v1.0.0/item-spec/json-schema/item.json

STAC Best Practices:
    Item name '20201211_223832_CS2' should only contain Searchable identifiers
    Identifiers should consist of only lowercase characters, numbers, '_', and '-'
    https://github.com/radiantearth/stac-spec/blob/master/best-practices.md#searchable-identifiers

    Item file names should match their ids: 'core-item' not equal to '20201211_223832_CS2

    Please avoid setting the datetime field to null, many clients search on this field

    A link to 'self' in links is strongly recommended


No ASSET format errors!

ASSET request errors:
    http://cool-sat.com/catalog/20201211_223832_CS2/20201211_223832_CS2.EPH

This object has 4 links

Link and Asset Validation

stac-check sample_files/1.0.0/core-item-bad-links.json --links --assets

stac-check: STAC spec validation and linting tool

Please upgrade from version 1.0.0 to version 1.1.0!

Validator: stac-validator 3.9.1

Valid ITEM: True

Schemas validated:
    https://schemas.stacspec.org/v1.0.0/item-spec/json-schema/item.json

STAC Best Practices:
    Item name '20201211_223832_CS2' should only contain Searchable identifiers
    Identifiers should consist of only lowercase characters, numbers, '_', and '-'
    https://github.com/radiantearth/stac-spec/blob/master/best-practices.md#searchable-identifiers

    Item file names should match their ids: 'core-item-bad-links' not equal to '20201211_223832_CS2

    Please avoid setting the datetime field to null, many clients search on this field

    A link to 'self' in links is strongly recommended


ASSET format errors:
    https:/storage.googleapis.com/open-cogs/stac-examples/20201211_223832_CS2.jpg

ASSET request errors:
    https:/storage.googleapis.com/open-cogs/stac-examples/20201211_223832_CS2.jpg
    http://cool-sat.com/catalog/20201211_223832_CS2/20201211_223832_CS2.EPH

LINK format errors:
    http:/remotdata.io/catalog/20201211_223832_CS2/index.html

LINK request errors:
    http://catalog/collection.json
    http:/remotdata.io/catalog/20201211_223832_CS2/index.html

This object has 4 links

Invalid STAC

stac-check sample_files/0.9.0/bad-item.json

stac-check: STAC spec validation and linting tool

Please upgrade from version 0.9.0 to version 1.1.0!

Validator: stac-validator 3.9.1

Valid : False

Schemas validated:
    https://cdn.staclint.com/v0.9.0/item.json

STAC Best Practices:
    A link to 'self' in links is strongly recommended

Validation error type:
    ValidationError
Validation error message:
    'id' is a required property of the root of the STAC object

This object has 5 links

Using HTTP Headers

stac-check https://stac-catalog.eu/collections/sentinel-s2-l2a/items/item1 --assets --no-assets-urls --header x-api-key $MY_API_KEY --header foo bar

stac-check: STAC spec validation and linting tool

Please upgrade from version 1.0.0 to version 1.1.0!

Validator: stac-validator 3.9.1

Valid ITEM: True

Schemas validated: 
    https://stac-extensions.github.io/timestamps/v1.1.0/schema.json
    https://schemas.stacspec.org/v1.0.0/item-spec/json-schema/item.json

STAC Best Practices: 
    A STAC collection should contain a summaries field
    It is recommended to store information like eo:bands in summaries


No ASSET format errors!

This object has 4 links

STAC API Validation

stac-check can validate STAC API endpoints, including item collections and collections endpoints. It supports pagination and can validate multiple pages of results.

Validating an Item Collection Endpoint:

stac-check https://stac.geobon.org/collections/chelsa-clim/items --item-collection

stac-check: STAC spec validation and linting tool

Validator: stac-validator 3.9.1

Item Collection: Validate all assets in a feature collection
Pages = 1

Valid ITEM: True

Schemas validated:
    https://schemas.stacspec.org/v1.0.0/item-spec/json-schema/item.json

This object has 10 items

Validating Multiple Pages of an Item Collection:

stac-check https://stac.geobon.org/collections/chelsa-clim/items --item-collection --pages 3

stac-check: STAC spec validation and linting tool

Validator: stac-validator 3.9.1

Item Collection: Validate all assets in a feature collection
Pages = 3

Valid ITEM: True

Schemas validated:
    https://schemas.stacspec.org/v1.0.0/item-spec/json-schema/item.json

This object has 30 items

Validating a Collections Endpoint:

stac-check https://stac.geobon.org/collections --collections

stac-check: STAC spec validation and linting tool

Validator: stac-validator 3.9.1

Collections: Validate all collections in a STAC API
Pages = 1

Valid COLLECTION: True

Schemas validated:
    https://schemas.stacspec.org/v1.0.0/collection-spec/json-schema/collection.json

This object has 5 collections

Development

Create local docs in the /docs folder:

$ pdoc --output-dir pdoc ./stac_check

Sponsors and Supporters

The following organizations have contributed time and/or funding to support the development of this project:

• Healy Hyperspatial
• Radiant Earth Foundation

We are grateful for the support of our sponsors who help make this project possible. If your organization uses stac-check and would like to become a sponsor, please reach out to us!

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

How to Contribute

• Fork the repository - Create your own fork of the project
• Create a feature branch - git checkout -b feature/your-feature-name
• Commit your changes - Make sure to write clear, concise commit messages
• Push to your branch - git push origin feature/your-feature-name
• Open a Pull Request - Describe your changes in detail

Development Guidelines

• Follow the existing code style
• Add tests for new features
• Update documentation as needed
• Make sure all tests pass before submitting a PR

Reporting Issues

If you find a bug or have a feature request, please open an issue on the GitHub repository.

License

This project is licensed under the Apache License 2.0.