Issues to consider before running the generator

The API for the new endpoints

You must identify which API (such as Common or Admin) to add the endpoints to. You cannot add custom endpoints to the Composite API, the System Tools API, or the Test Util API.

The parent of the custom resource

In most cases, the custom entity is the child of an existing entity (such as a claim or an account). The custom entity may be a direct child of a single parent. But the custom entity could also be part of a hierarchy that is several levels deep. When the custom entity has multiple ancestors, you have a choice in the structure of the endpoint path.

For example, suppose you have a CustomEntity_Ext entity which is the child of ClaimContact, and ClaimContact is the child of Claim. When you generate the endpoints, you can make the custom resource a descendent of its immediate parent (ClaimContact), or a distant ancestor (Claim).

Choosing the immediate parent

If you choose the immediate parent, then your endpoints look like this:

GET /claims/{claimId}/contacts/{contactId}/custom-entities-ext
POST /claims/{claimId}/contacts/{contactId}/custom-entities-ext
GET /claims/{claimId}/contacts/{contactId}/custom-entities-ext/{customEntityExtId}
PATCH /claims/{claimId}/contacts/{contactId}/custom-entities-ext/{customEntityExtId}
DELETE /claims/{claimId}/contacts/{contactId}/custom-entities-ext/{customEntityExtId}

With this approach, you cannot retrieve all CustomEntity_Ext instances for a single Claim in one call. You would need to make multiple calls, one for each ClaimContact.

When you create a new CustomEntity_Ext, the immediate parent (the ClaimContact) is specified in the URL. Therefore, the new resource is linked to its immediate parent.

Choosing a distant ancestor

If you choose a distant ancestor, such as Claim, then your endpoints look like this:

GET /claims/{claimId}/custom-entities-ext
POST /claims/{claimId}/custom-entities-ext
GET /claims/{claimId}/custom-entities-ext/{customEntityExtId}
PATCH /claims/{claimId}/custom-entities-ext/{customEntityExtId}
DELETE /claims/{claimId}/custom-entities-ext/{customEntityExtId}

With this approach, you can retrieve all CustomEntity_Ext instances for a single Claim in one call.

When you create a new CustomEntity_Ext, the immediate parent (the ClaimContact) is not specified in the URL. Therefore, the new resource is not automatically linked to its immediate parent. (It may be possible to link the new resource to its immediate parent by explicitly adding it to the request payload.)

Making the choice

From a technical standpoint, either choice is valid. The best choice depends on the types of GETs and POSTs you plan to execute most frequently.

Populating collections

One of the GET endpoints retrieves a collection. This collection can be retrieved using either a stream or a Gosu query.

A stream loads the entire collection into memory before manipulating it. Streams have the advantage of being objects that developers may be more familiar with. Filtering and sorting may be easier with stream-backed resources as the whole collection is loaded into memory. However, streams may degrade performance if the size of the collection is too large.

Gosu queries are expressions that are converted into SQL queries. Queries have a maximum number of elements that are loaded into memory at one time. Queries have the advantage of preserving performance if the size of the entire collection is large, as the collection is loaded in portions. However, if you are not familiar with Gosu, you may find it harder to write complex query logic.

Guidewire has the following recommendations:

If the collection is likely to be large, use a Gosu query.
Otherwise, use a stream.

With streams, you will need to write code to populate the stream. This is easy to do when the parent entity has an array of custom entities, as the array can be converted into a stream. Therefore, if you decide to use streams, you may want to add an array of custom entities to the parent, even if the application does not otherwise require an array.

External callers (such as insureds or producers) may not have access to third-party data on claims (such as contact and vehicle information related to a vehicle that the insured damaged). For these types of callers, access to specific fields may be restricted by additional accessible fields filters. For fields restricted by additional accessible fields filters, the behavior of sorts and filters changes based on whether the collection is populated by a stream or query. For more information, see Sorting and filtering on accessible fields.

Additional considerations

You must identify the API roles that will have GET, POST, PATCH, and DELETE access to the custom endpoints.

You can add the custom resource to an integration graph. For more information, see Integration graphs.

If the custom entity has subtypes, you can generate either a single set of shared endpoints to work with supertype and subtype behavior simultaneously, or you generate separate sets of shared endpoint that work with each supertype or subtype independently. For more information, see Supertype entities.

Naming conventions during generation

Entity Ext prefix or suffix

The REST endpoint generator expects custom entities to conform to the naming convention of starting or ending with "Ext". (This convention is designed to prevent custom entities from conflicting with base configuration entities added in future releases.) If the custom entity does not start or end with Ext, the REST endpoint generator adds an "ext" suffix to the name. For example, suppose you have a custom entity named CustomEntity. After the REST endpoint generator runs:

The element resource is named CustomEntityExt
The collection resource is named CustomEntitiesExt

Plural name for resource

The REST endpoint generator provides a default name for the resource collection. Guidewire recommends naming this using the plural form of the custom entity name. The REST endpoint generator guesses the correct plural. If the guess is incorrect (such as guessing CustomChildsExt instead of CustomChildrenExt), you can modify the default.

Hyphenation in paths

The endpoint paths consist of custom entity name converted into lower case letters, numbers, and hyphens. Certain characters or character combinations in the entity name cause the path to be generated in a particular way.

Upper-case letters are converted to lower letters. (The path for Inspector_Ext is /inspector-ext.)
Underscores are converted to hyphens. (The path for Inspector_Ext is /inspector-ext.)
Single capital letters in the middle of the name are preceded with a hyphen. (The path for SecuritySystem_Ext is /security-system-ext.)
If the entity name contains multiple capital letters in a row (such as BOPLine_Ext), the REST endpoint generator guesses at the correct way to apply hyphenation (such as /bop-line-ext). If the guess is incorrect (such as being given USBOPLine_Ext and guessing /usbop-line-ext instead of /us-bop-line), you can modify the default.

Policy graph entities

Policy graph entities are entities that have Policy as a direct or indirect parent. For example, VehicleIncident, Coverage, and Exposure are all policy graph entities.

When the REST endpoint generator creates endpoints for a custom policy graph entity, its executes the process differently than for non-policy graph entities. There are additional issues to consider, and differences in the configurations to be done.

For more information, see Policy descendant entities.