--- url: >- https://canary.warp-drive.io/api/@warp-drive/legacy/model/migration-support/classes/DelegatingSchemaService.md description: >- Legacy schema service that serves a resource's schema from the primary service when it has one, and otherwise from its `Model` class, for incremental migration. --- # DelegatingSchemaService Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:573](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L573) See the class documentation above for usage. ## Implements * `SchemaService` ## Constructors ### Constructor ```ts new DelegatingSchemaService(store: Store$1, schema: SchemaService): DelegatingSchemaService; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:601](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L601) #### Parameters ##### store `Store$1` ##### schema `SchemaService` #### Returns `DelegatingSchemaService` ## Methods ### attributesDefinitionFor()? ```ts optional attributesDefinitionFor(resource: | ResourceKey | { type: string; }): AttributesSchema; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:578](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L578) Delegates to whichever of the primary/fallback schema services has a schema for the resource, preferring the primary. See [isDelegated](#isdelegated). #### Parameters ##### resource | [`ResourceKey`](../../../../core/types/identifier/types/ResourceKey.md) | { `type`: `string`; } #### Returns `AttributesSchema` *** ### cacheFields()? ```ts optional cacheFields(resource: { type: string; }): Map; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:639](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L639) Queries for the fields of a given resource type or resource identity. Should error if the resource type is not recognized. #### Parameters ##### resource ###### type `string` #### Returns [`Map`](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Map)<`string`, | [`LegacyBelongsToField`](../../../../core/types/schema/fields/types/LegacyBelongsToField.md) | [`LegacyHasManyField`](../../../../core/types/schema/fields/types/LegacyHasManyField.md) | [`LinksModeBelongsToField`](../../../../core/types/schema/fields/types/LinksModeBelongsToField.md) | [`LinksModeHasManyField`](../../../../core/types/schema/fields/types/LinksModeHasManyField.md) | [`LegacyAttributeField`](../../../../core/types/schema/fields/types/LegacyAttributeField.md) | [`GenericField`](../../../../core/types/schema/fields/types/GenericField.md) | [`ObjectField`](../../../../core/types/schema/fields/types/ObjectField.md) | [`SchemaObjectField`](../../../../core/types/schema/fields/types/SchemaObjectField.md) | [`ArrayField`](../../../../core/types/schema/fields/types/ArrayField.md) | [`SchemaArrayField`](../../../../core/types/schema/fields/types/SchemaArrayField.md) | [`ResourceField`](../../../../core/types/schema/fields/types/ResourceField.md) | [`CollectionField`](../../../../core/types/schema/fields/types/CollectionField.md)> *** ### CAUTION\_MEGA\_DANGER\_ZONE\_arrayExtensions() ```ts CAUTION_MEGA_DANGER_ZONE_arrayExtensions(field: ExtensibleField): | Map | null; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:700](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L700) Retrieve the extension map for an array field #### Parameters ##### field `ExtensibleField` #### Returns | [`Map`](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Map)<`string` | `symbol`, `ExtensionDef`> | `null` *** ### CAUTION\_MEGA\_DANGER\_ZONE\_hasExtension() ```ts CAUTION_MEGA_DANGER_ZONE_hasExtension(ext: { kind: "object" | "array"; name: string; }): boolean; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:679](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L679) Check if a specific extension has been registered previously #### Parameters ##### ext ###### kind `"object"` | `"array"` ###### name `string` #### Returns `boolean` *** ### CAUTION\_MEGA\_DANGER\_ZONE\_objectExtensions() ```ts CAUTION_MEGA_DANGER_ZONE_objectExtensions(field: ExtensibleField, resolvedType: string | null): | Map | null; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:693](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L693) Retrieve the extension map for an object field #### Parameters ##### field `ExtensibleField` ##### resolvedType `string` | `null` #### Returns | [`Map`](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Map)<`string` | `symbol`, `ExtensionDef`> | `null` *** ### CAUTION\_MEGA\_DANGER\_ZONE\_registerExtension() ```ts CAUTION_MEGA_DANGER_ZONE_registerExtension(extension: CAUTION_MEGA_DANGER_ZONE_Extension): void; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:683](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L683) Register an extension for either objects or arrays See also CAUTION\_MEGA\_DANGER\_ZONE\_Extension #### Parameters ##### extension `CAUTION_MEGA_DANGER_ZONE_Extension` #### Returns `void` *** ### CAUTION\_MEGA\_DANGER\_ZONE\_resourceExtensions() ```ts CAUTION_MEGA_DANGER_ZONE_resourceExtensions(resource: | ResourceKey | { type: string; }): | Map | null; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:687](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L687) Retrieve the extension map for a resource #### Parameters ##### resource | [`ResourceKey`](../../../../core/types/identifier/types/ResourceKey.md) | { `type`: `string`; } #### Returns | [`Map`](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Map)<`string` | `symbol`, `ExtensionDef`> | `null` *** ### derivation() ```ts derivation(field: | DerivedField | { type: string; }): Derivation; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:654](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L654) Returns the derivation registered with the name provided by `field.type`. Validates that the field is a valid DerivedField. #### Parameters ##### field | [`DerivedField`](../../../../core/types/schema/fields/types/DerivedField.md) | { `type`: `string`; } #### Returns [`Derivation`](../../../../core/types/schema/concepts/types/Derivation.md) *** ### doesTypeExist()? ```ts optional doesTypeExist(type: string): boolean; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:588](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L588) Whether either the primary or fallback schema service has a schema for the given type. #### Parameters ##### type `string` #### Returns `boolean` *** ### fields() ```ts fields(resource: | ResourceKey | { type: string; }): Map; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:633](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L633) Queries for the fields of a given resource type or resource identity. Should error if the resource type is not recognized. #### Parameters ##### resource | [`ResourceKey`](../../../../core/types/identifier/types/ResourceKey.md) | { `type`: `string`; } #### Returns [`Map`](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Map)<`string`, [`FieldSchema`](../../../../core/types/schema/fields/types/FieldSchema.md)> *** ### hashFn() ```ts hashFn(field: | HashField | { type: string; }): HashFn; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:651](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L651) Returns the hash function registered with the name provided by `field.type`. Validates that the field is a valid HashField. #### Parameters ##### field | [`HashField`](../../../../core/types/schema/fields/types/HashField.md) | { `type`: `string`; } #### Returns [`HashFn`](../../../../core/types/schema/concepts/types/HashFn.md) *** ### hasResource() ```ts hasResource(resource: | ResourceKey | { type: string; }): boolean; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:618](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L618) Queries whether the SchemaService recognizes `type` as a resource type #### Parameters ##### resource | [`ResourceKey`](../../../../core/types/identifier/types/ResourceKey.md) | { `type`: `string`; } #### Returns `boolean` *** ### hasTrait() ```ts hasTrait(type: string): boolean; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:621](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L621) Queries whether the SchemaService recognizes `type` as a resource trait #### Parameters ##### type `string` #### Returns `boolean` *** ### isDelegated() ```ts isDelegated(resource: | ResourceKey | { type: string; }): boolean; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:610](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L610) Whether the given resource's schema is being served by the fallback (legacy Model-derived) schema service rather than the primary one. #### Parameters ##### resource | [`ResourceKey`](../../../../core/types/identifier/types/ResourceKey.md) | { `type`: `string`; } #### Returns `boolean` *** ### registerDerivation() ```ts registerDerivation(derivation: Derivation): void; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:672](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L672) Enables registration of a derivation. The derivation can later be retrieved by the name attached to it's `[Type]` property. #### Type Parameters ##### R `R` ##### T `T` ##### FM `FM` *extends* | [`ObjectValue`](../../../../core/types/json/raw/types/ObjectValue.md) | `null` #### Parameters ##### derivation [`Derivation`](../../../../core/types/schema/concepts/types/Derivation.md)<`R`, `T`, `FM`> #### Returns `void` *** ### registerHashFn() ```ts registerHashFn(hashFn: HashFn): void; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:675](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L675) Enables registration of a hashing function The hashing function can later be retrieved by the name attached to it's `[Type]` property. #### Parameters ##### hashFn [`HashFn`](../../../../core/types/schema/concepts/types/HashFn.md) #### Returns `void` *** ### registerResource() ```ts registerResource(schema: | ResourceSchema | ObjectSchema): void; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:666](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L666) Enables registration of a single Schema representing either a resource in PolarisMode or LegacyMode or an ObjectSchema representing an embedded structure in other schemas. This can be useful for either pre-loading schema information or for registering schema information delivered by API calls or other sources just-in-time. #### Parameters ##### schema | [`ResourceSchema`](../../../../core/types/schema/fields/types/ResourceSchema.md) | [`ObjectSchema`](../../../../core/types/schema/fields/types/ObjectSchema.md) #### Returns `void` *** ### registerResources() ```ts registerResources(schemas: ( | ResourceSchema | ObjectSchema)[]): void; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:663](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L663) Enables registration of multiple Schemas at once. This can be useful for either pre-loading schema information or for registering schema information delivered by API calls or other sources just-in-time. #### Parameters ##### schemas ( | [`ResourceSchema`](../../../../core/types/schema/fields/types/ResourceSchema.md) | [`ObjectSchema`](../../../../core/types/schema/fields/types/ObjectSchema.md))\[] #### Returns `void` *** ### registerTransformation() ```ts registerTransformation(transform: Transformation): void; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:669](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L669) Enables registration of a transformation. The transformation can later be retrieved by the name attached to it's `[Type]` property. #### Parameters ##### transform [`Transformation`](../../../../core/types/schema/concepts/types/Transformation.md) #### Returns `void` *** ### relationshipsDefinitionFor()? ```ts optional relationshipsDefinitionFor(resource: | ResourceKey | { type: string; }): RelationshipsSchema; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:583](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L583) Delegates to whichever of the primary/fallback schema services has a schema for the resource, preferring the primary. See [isDelegated](#isdelegated). #### Parameters ##### resource | [`ResourceKey`](../../../../core/types/identifier/types/ResourceKey.md) | { `type`: `string`; } #### Returns `RelationshipsSchema` *** ### resource() ```ts resource(resource: | ResourceKey | { type: string; }): | ResourceSchema | ObjectSchema; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:657](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L657) Returns the schema for the provided resource type. #### Parameters ##### resource | [`ResourceKey`](../../../../core/types/identifier/types/ResourceKey.md) | { `type`: `string`; } #### Returns | [`ResourceSchema`](../../../../core/types/schema/fields/types/ResourceSchema.md) | [`ObjectSchema`](../../../../core/types/schema/fields/types/ObjectSchema.md) *** ### resourceHasTrait() ```ts resourceHasTrait(resource: | ResourceKey | { type: string; }, trait: string): boolean; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:627](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L627) Queries whether the given resource has the given trait #### Parameters ##### resource | [`ResourceKey`](../../../../core/types/identifier/types/ResourceKey.md) | { `type`: `string`; } ##### trait `string` #### Returns `boolean` *** ### resourceTypes() ```ts resourceTypes(): readonly string[]; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:614](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L614) Returns all known resource types #### Returns readonly `string`\[] *** ### transformation() ```ts transformation(field: | GenericField | ObjectField | ArrayField | { type: string; }): Transformation; ``` Defined in: [warp-drive-packages/legacy/src/model/migration-support.ts:648](https://github.com/warp-drive-data/warp-drive/blob/48dc0d277b98008082669dadc6a52e5c5682ef8e/warp-drive-packages/legacy/src/model/migration-support.ts#L648) Returns the transformation registered with the name provided by `field.type`. Validates that the field is a valid transformable. #### Parameters ##### field | [`GenericField`](../../../../core/types/schema/fields/types/GenericField.md) | [`ObjectField`](../../../../core/types/schema/fields/types/ObjectField.md) | [`ArrayField`](../../../../core/types/schema/fields/types/ArrayField.md) | { `type`: `string`; } #### Returns [`Transformation`](../../../../core/types/schema/concepts/types/Transformation.md)