Add support for "include" and "fields" to findById (REST API)

[bajtos]

Let's say our application has a Customer model that has many Order instances.

In LoopBack 3.x, one can can fetch a customer with all their orders.

GET /api/customers/123?filter[include]=orders

We should support this feature in LoopBack 4 too.

Acceptance criteria

• Find which Filter properties are supported by findById
• Create a new TypeScript interface describing these properties. This new interface should be most likely provided by loopback-datasource-juggler.
• Modify EntityCrudRepository.prototype.findById - fix the type of the filter argument to use the new TypeScript type describing only the properties supported by findById. Fix all implementations of this interface, include tests.
• Create a function for obtaining JSON Schema and OpenAPI schema for this new interface. Build on top of REST API to find models using a filter  #1679
• Update Sequence that we support these two fields for findById.
• Throw errors ( or warning) when use order, skip, limit, and where clauses with findById. See Filter on findById is ignoring the where clause #3336.

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Done in #4114

• Update the REST Controller template and all example controllers to support this new filter parameter.
• Update any documentation pages and snapshot tests showing findById implementation to include the new filter argument.

Note: the argument name filter may not be descriptive enough, feel free to find a better name.

IMPORTANT: This feature depends on #1352.

[mrbatista]

@bajtos is duplicate of #1352?
In loopback 3.x is it possible to use include for find(), findById(), findOne().
Does loopback 4 support only findById()?

[bajtos]

In loopback 3.x is it possible to use include for find(), findById(), findOne().
Does loopback 4 support only findById()?

LoopBack 4 does not support inclusion of related models yet. The issue #1352 is keeping track of implementing support for filter[include] at Repository level for find/findOne/findById and it's a pre-requisite for this issue.

[stale]

This issue has been marked stale because it has not seen activity within six months. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository. This issue will be closed within 30 days of being stale.

[tayyabjamil]

any updates?