Updating callable functions documentation

[tdkehoe]

In app.module.ts I put in commented out lines anticipating AngularFire 7. When AngularFire 7 is available for callable functions we can easily update the documentation with a few clicks.

I also put in two lines showing how to run your functions in the Firebase emulator. I clearly indicated how to comment out these lines to run your functions in the cloud.

I made an HTML view to show how to handle user input. Also I added a second set of curly brackets to {{ data$ | async }}. This is necessary to make the code run without throwing errors.

In app.component.ts I put in lines anticipating AngularFire 7.

I moved the template to an HTML view.

I added a variable data$ to handle the data returned from the cloud function. I added this to fns.httpsCallable('my-fn-name');. These changes are necessary to make the code run without throwing errors.

I changed fns to functions for readability.

I made two functions, one that executes on page load and the user executes on user input.

I put in the index.js file showing the cloud functions. The old documentation was confusing as to what data went from Angular to the cloud function and what data was returned from the cloud function. Showing the index.js functions clarifies this.

I've written a longer tutorial at https://github.com/tdkehoe/Firebase-Cloud-Functions-with-Angular/blob/main/README.md.

When can we expect to use AngularFire 7 with callable functions?

Checklist

• Issue number for this PR: #nnn (required)
• Docs included?: (yes)
• Test units included?: (no)
• In a clean directory, yarn install, yarn test run successfully? (no)

Description

Updating the documentation for callable functions. The existing documentation has a few problems:

• A few syntax errors in the component controller throw errors.
• Doesn't show how to use the Firebase emulator.
• Doesn't show how to call a function from user input, e.g., clicking a button in the view.
• Is confusing about what data is sent from Angular to the cloud function and what data is returned from the cloud function to Angular.
• Doesn't show how to use AngularFire 7.