i want to know step by step procedure to use API to get data in CAP format

[Avanishchaurasiya]

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[scadergit]

This made me look back over the Examples tab on the documentation page and realize the Alerts example is missing details on the common CAP format. I'll add those shortly. Until then...

The most important step in requesting CAP is setting the request Accept header. Alert endpoints either return a list of alert summaries, or details of a single alert. The lists use ATOM, and the details use CAP. You can also use the default JSON to discover then request CAP for specific alerts.

To return a list in ATOM, the request should use the Accept header application/atom+xml. Lists include all /alerts endpoints except the /alerts/{id} endpoint. To return details of a specific alert in CAP, the request should use the Accept header application/cap+xml. Details are only returned for a specific alert using the /alerts/{id} endpoint.

If you already know the alert id, you can directly request the /alerts/{id} endpoint. For example (note this id will expire at some point and be invalid):
https://api.weather.gov/alerts/NWS-IDP-PROD-4136017-3504489

Here is an example of using an Accept header for CAP in curl:
curl -H "Accept: application/cap+xml" https://api.weather.gov/alerts/NWS-IDP-PROD-4136017-3504489

The other /alerts endpoints and parameters can be used to discover alert ids, including active alerts using the /alerts/active endpoint. For example:
https://api.weather.gov/alerts/active

Here is an example of using an Accept header for ATOM in curl:
curl -H "Accept: application/atom+xml" https://api.weather.gov/alerts/active