Fix/separate app stack settings

[abarciauskas-bgse]

Add root_path and veda_custom_host to replicate developmentseed/titiler-multidim#87

[github-actions]

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[abarciauskas-bgse]

I have verified this is now working via this tile request and visiting the API docs landing page.

It does seem a bit duplicative that TITILER_CMR_ROOT_PATH is defined by AppSettings in infrastructure/aws/config.py in order to be passed as an environment variable to the lambda run time for use ApiSettings in titiler/cmr/main.py but I haven't thought of a better way to pass environment variables between the stack deployment and the app run time...

[hrodmn]

It does seem a bit duplicative that TITILER_CMR_ROOT_PATH is defined by AppSettings in infrastructure/aws/config.py in order to be passed as an environment variable to the lambda run time for use ApiSettings in titiler/cmr/main.py but I haven't thought of a better way to pass environment variables between the stack deployment and the app run time...

Agreed. The number of variable handoffs is a little out of control especially when you go all the way up to the veda-deploy level! I did not try experimenting with the whole custom host and root path situation when I did this in titiler-multidim - I just followed some example from a different veda service.

I guess we could eliminate the infrastructure AppSettings and just load things directly from env vars at deploy time, but the pydantic settings are a convenient interface for validation and defining defaults. I think we are stuck with the env var -> settings in the titiler-cmr application since we don't compile the app to encode these variables in the runtime.