Refactor (Layer of Indirection) for Resource Fetch

[josh-byster]

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We will be integrating with potentially multiple data sources (Mongo or a mock API for automated testing and dev work), while integrating with Salesforce for production. Currently, we have the retrieval of these resources directly embedded within the endpoints (i.e. the request to our database and that business logic happens within our backend). However, it would be ideal if that logic is handled through an external source, such that we can call getAllResources and the logic would be handled depending on what environment variable is set.

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There's a few ways we can architect this to ease our transition to using Salesforce in production. One way we might handle this would be through a small library we create within our backend that we can call into directly as part of our route handler for, say, GET /resources/. I envision us having an environment variable keeping track of the two use-cases: salesforce backend and our custom (Mongo) backend, and then have the library handle this logic. We essentially want to build an API for our backend API to consume (API galore!) so all the logic is abstracted.