You can invoke Cloud Functions with an HTTP request using the POST , PUT , GET , DELETE , and OPTIONS HTTP methods. To create an HTTP endpoint for your function, specify –trigger-http as the trigger type when deploying your function .
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The Cloud Functions for Firebase client SDKs let you call functions directly from a Firebase app. To call a function from your app in this way, write and deploy an HTTPS Callable function in Cloud Functions, and then add client logic to call the function from your app .
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