Support reference resolution in the key field not only id in ResourceIdentifiers

[heshamMassoud]

Edit: The task is resolved, so only parts are related to the API, not SDK anymore, when API adds support of ResourceIdentifier for PriceDraft#customerGroup we could close the issue. (Currently it's not clear when API will support this.)

Remaining work:

Support requests (SUPPORT-9797, SUPPORT-9798) are opened for the problematic types/fields both API and SDK. Additionally, a GitHub issue is opened for jvm-sdk types: commercetools/commercetools-jvm-sdk#2052 (Edit: The task is resolved, so only parts are related to the API, not SDK anymore.)

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Description

Right now there are references which are of type Reference and other references which are of type ResourceIdentifier

1. Reference only supports id as a field.
2. ResourceIdentifier supports id or key as a field.

On CTP in the future, all references should be changed to ResourceIdentifier.

It's quite confusing for the user of the sync library to put the key in the id field for reference resolution.

Current Behaviour

Whether it's a resourceIdentifier or reference reference resolution is always done on the id field.

Expected Behaviour

1. When the reference is of type ResourceIdentifier:
   • If the key field is set, sync lib should check if resource exists or not, and keep track of missing references (as done in cat sync) as it might be resolved in later batches.
   • If the id field is set, then it is an evidence of resource existence on CTP, so we can issue an update/create API request right away.
2. When the reference is of type Reference:
   • Do reference resolution as it currently is (key -> id mapping).

Related: #231

[butenkor]

As defined by @ahmetoz

References on commercetools-sync-java

ProductDraft

field	commercetools type	required/optional	JVM SDK draft type	status
productType	ResourceIdentifier to a ProductType	Required	ResourceIdentifier<ProductType>	✔️
categories	Array of ResourceIdentifier for a Category	Optional	Set<ResourceIdentifier<Category>>	✔️
taxCategory	ResourceIdentifier to a TaxCategory	Optional	ResourceIdentifier<TaxCategory>	✔️
state	ResourceIdentifier to a State	Optional	ResourceIdentifier<State>	✔️

PriceDraft

field	commercetools type	required/optional	JVM SDK draft type	status
customerGroup	Reference to a CustomerGroup	Optional	Reference<CustomerGroup>	⚠️
channel	ResourceIdentifier to a Channel	Optional	ResourceIdentifier<Channel>	✔️

CustomFieldDraft

field	commercetools type	required/optional	JVM SDK draft type	status
type	ResourceIdentifier to a Type	Required	ResourceIdentifier<Type>	✔️

CategoryDraft

field	commercetools type	required/optional	JVM SDK draft type	status
parent	ResourceIdentifier to a Category	Optional	ResourceIdentifier<Category>	✔️

InventoryEntryDraft

field	commercetools type	required/optional	JVM SDK draft type	status
supplyChannel	ResourceIdentifier to a Channel	Optional	ResourceIdentifier<Channel>	✔️

CartDiscountDraft

field	commercetools type	required/optional	JVM SDK draft type	status
supplyChannel	ResourceIdentifier to a Channel	Optional	ResourceIdentifier<Channel>	✔️

Not implemented yet

CustomerDraft

field	commercetools type	required/optional	JVM SDK draft type	status
stores	Array of ResourceIdentifier to a Store	Optional	List<ResourceIdentifier<Store>>	✔️
customerGroup	ResourceIdentifier to a CustomerGroup	Optional	ResourceIdentifier<CustomerGroup>	✔️

ShoppingListDraft

field	commercetools type	required/optional	JVM SDK draft type	status
customer	ResourceIdentifier to a Customer	Optional	ResourceIdentifier<Customer>	✔️

[butenkor]

As defined by @ahmetoz:

Support requests (SUPPORT-9797, SUPPORT-9798) are opened for the problematic types/fields both API and SDK and links are shared with @butenkor . Additionally, a GitHub issue is opened for jvm-sdk types: commercetools/commercetools-jvm-sdk#2052

[ahmetoz]

Released with: https://github.com/commercetools/commercetools-sync-java/blob/master/docs/RELEASE_NOTES.md#200---sept-14-2020

[ahmetoz]

The task is resolved, so only parts are related to the API, not SDK anymore, when API adds support of ResourceIdentifier for PriceDraft#customerGroup we could close the issue. (Currently, it's not clear when API will support this.)