feat(event-handler): Add AppSync handler decorator

[michaelbrewer]

Issue #, if available:

#356

Description of changes:

Changes:

• Relocate AppSyncResolver to aws_lambda_powertools/event_handler
• Add docstrings for AppSyncResolver
• Fixed aws_lambda_powertools/utilities/data_classes/__init__.py imports
• Add initial markdown docs for AppSyncResolver
• Add current_event and lambda_context to AppSyncResolver

UX example:

from aws_lambda_powertools.event_handler import AppSyncResolver

app = AppSyncResolver()

@app.resolver(type_name="Query", field_name="listLocations")
def list_locations(page: int = 0, size: int = 10):
    """ Your logic to fetch locations """

@app.resolver(type_name="Merchant", field_name="extraInfo")
def get_extra_info():
     """ Can use "app.current_event.source" to filter within the parent context  """

@app.resolver(field_name="commonField")
def common_field():
     """ Would match all fieldNames matching 'commonField'  """


def handle(event, context):
    app.resolve(event, context)

Checklist

• Meet tenets criteria
• Update tests
• Update docs
• PR title follows conventional commit semantics

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[michaelbrewer]

@heitorlessa i moved this to the event_handler location. Just have not added a new section in the docs for event_handler

[codecov-io]

Codecov Report

Merging #363 (02818db) into develop (9f08fa6) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop     #363      +/-   ##
===========================================
- Coverage    99.94%   99.94%   -0.01%     
===========================================
  Files           97       98       +1     
  Lines         3687     3686       -1     
  Branches       175      173       -2     
===========================================
- Hits          3685     3684       -1     
  Partials         2        2              

Impacted Files	Coverage Δ
aws_lambda_powertools/event_handler/__init__.py	100.00% <100.00%> (ø)
aws_lambda_powertools/event_handler/appsync.py	100.00% <100.00%> (ø)
...mbda_powertools/utilities/data_classes/__init__.py	100.00% <100.00%> (ø)

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[heitorlessa]

I like how simple the UX is, and mostly intuitive. I've added some comments on debugging statements, internal naming and conventions, and the move to a core utility (in 2.0 we will cease to call core vs general utility).

[heitorlessa]

Summarizing, as once this is done, we are ready to prep for a new release.

1. Move to the root instead of utilities/ - We’ll treat this as a core utility, so same for Docs placement
2. Docstring to have a sample return: feat(event-handler): Add AppSync handler decorator #363 (comment)
3. Debug statements, for example registering a resolver, and any other area you see it’d be helpful to debug issues raised
4. The changes we discussed on Slack - remove include_event, bring in current_event, and lambda_context, etc.
5. Optionally (I can do that) - Getting started vs Advanced docs, we should be providing a simple example to get started with (AppSync Direct Lambda Resolver) and only then Amplify-CLI @function

[michaelbrewer]

Summarizing, as once this is done, we are ready to prep for a new release.

1. Move to the root instead of utilities/ - We’ll treat this as a core utility, so same for Docs placement
2. Docstring to have a sample return: #363 (comment)
3. Debug statements, for example registering a resolver, and any other area you see it’d be helpful to debug issues raised
4. The changes we discussed on Slack - remove include_event, bring in current_event, and lambda_context, etc.
5. Optionally (I can do that) - Getting started vs Advanced docs, we should be providing a simple example to get started with (AppSync Direct Lambda Resolver) and only then Amplify-CLI @function

Most of this has been done, regarding the documentation I would help to have a complete example for both. Either in the core docs or a referenced article/blog post and repo

[heitorlessa]

looking :)

[heitorlessa]

Last minor change to ease coming back at this code (gotta resolver the resolvers within resolvers :D)

Everything else is good to go!