4. How to make a custom asset for STAC-Collection and STAC-Item:

This tutorial will demonstrate the process of creating a personalised asset for STAC-Collection and STAC-Item.

In order to create a customised asset, it is necessary to understand the composition of the asset_properties in both the STAC-Collection and STAC-Item. The asset_properties has a dictionary with keys that can be used to enable or disable certain services in TDS within the STAC-Collection and STAC-Item.

Two keys associated with custom assets are collection_custom_asset and item_custom_asset. Both situations use two keys, which are lists of dictionaries. Each dictionary within the lists contains the following keys:

1. key: This key is a string used to identify the custom asset.

2. href: This attribute is a string that specifies the URL of the custom asset.

3. title: This key is a string that specifies the custom asset’s title.

4. The roles key is a list that specifies the custom asset’s roles.

   Note

   The roles key is optional. If it is not specified, the default value is ["data"]. For more information refer to the roless section of the PySTAC documentation.

   Note

   The roles key is a list. If you want to specify multiple roless, you can use the following format:

   "roles": ["roles1", "roles2", "roles3", ...]
   

5. The media_type key is a string that specifies the media type of the custom asset.

   Note

   The media_type key is optional. If it is not specified, the default value is None. For more information refer to the Media Type section of the PySTAC documentation.

For example, if we want to make a custom asset for STAC-Collection and STAC-Item, we can use following dictionary:

asset_properties = {
            "collection_custom_asset": [
                {
                    "key": "key1",
                    "href": "href1",
                    "title": "title1",
                    "roles": ["roles1"],
                    "media_type": "media_type1",
                },
                {
                    "key": "key2",
                    "href": "href2",
                    "title": "title2",
                    "roles": ["roles2"],
                    "media_type": "media_type2",
                },
                {
                    "key": "key3",
                    "href": "href3",
                    "title": "title3",
                    "roles": ["roles3"],
                    "media_type": "media_type3",
                }
            ],
            "item_custom_asset": [
                {
                    "key": "key1",
                    "href": "href1",
                    "title": "title1",
                    "roles": ["roles1"],
                    "media_type": "media_type1",
                },
                {
                    "key": "key2",
                    "href": "href2",
                    "title": "title2",
                    "roles": ["roles2"],
                    "media_type": "media_type2",
                },
                {
                    "key": "key3",
                    "href": "href3",
                    "title": "title3",
                    "roles": ["roles3"],
                    "media_type": "media_type3",
                }
            ]
        }