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Documentation / @ember-data/store / types / SchemaService

Interface: SchemaService ​

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:62

The SchemaService provides the ability to query for information about the structure of any resource type.

Applications can provide any implementation of the SchemaService they please so long as it conforms to this interface.

The design of the service means that schema information could be lazily populated, derived-on-demand, or progressively enhanced during the course of an application's runtime. The primary requirement is merely that any information the service needs to correctly respond to an inquest is available by the time it is asked.

The @ember-data/model package provides an implementation of this service which makes use of your model classes as the source of information to respond to queries about resource schema. While this is useful, this may not be ideal for your application. For instance, Schema information could be sideloaded or pre-flighted for API calls, resulting in no need to bundle and ship potentially large and expensive JSON or large Javascript based Models to pull information from.

To register a custom schema implementation, implement the store's createSchemaService hook to return an instance of your service.

ts
import Store from '@ember-data/store';
import CustomSchemas from './custom-schemas';

export default class extends Store {
  createSchemaService() {
    return new CustomSchemas();
  }
}

At runtime, both the Store and the CacheCapabilitiesManager provide access to this service via the schema property.

ts
export default class extends Component {
 @service store;

 get fields() {
   return this.store
     .schema
     .fields(this.args.dataType);
 }
}

Methods ​

attributesDefinitionFor()? ​

ts
optional attributesDefinitionFor(identifier): AttributesSchema;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:256

DEPRECATED - use fields instead

Returns definitions for all properties of the specified resource that are considered "attributes". Generally these are properties that are not related to book-keeping state on the client and do not represent a linkage to another resource.

The return value should be a dictionary of key:value pairs where the key is the attribute or property's name and value is an object with at least the property name which should also match key.

Optionally, this object may also specify type, which should be a string reference to a transform, and options which should be dictionary in which any key:value pairs are permissable.

For instance, when using @ember-data/model, the following attribute definition:

ts
class extends Model {
  @attr('string', { defaultValue: 'hello' }) greeting;
  @attr('date') birthday;
  @attr firstName;
}

Would be returned as:

js
{
  greeting: { name: 'greeting', type: 'string', options: { defaultValue: 'hello' } },
  birthday: { name: 'birthday', type: 'date' },
  firstName: { name: 'firstName' }
}

Parameters ​

identifier ​

ObjectWithStringTypeProperty | RecordIdentifier

Returns ​

AttributesSchema

Deprecated ​

cacheFields()? ​

ts
optional cacheFields(resource): Map<string, 
  | LegacyAttributeField
  | LegacyBelongsToField
  | LegacyHasManyField
  | LinksModeBelongsToField
  | LinksModeHasManyField
  | GenericField
  | ObjectField
  | SchemaObjectField
  | ArrayField
  | SchemaArrayField
  | ResourceField
| CollectionField>;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:105

Queries for the fields of a given resource type or resource identity.

Should error if the resource type is not recognized.

Parameters ​

resource ​

StableRecordIdentifier | ObjectWithStringTypeProperty

Returns ​

Map<string, | LegacyAttributeField | LegacyBelongsToField | LegacyHasManyField | LinksModeBelongsToField | LinksModeHasManyField | GenericField | ObjectField | SchemaObjectField | ArrayField | SchemaArrayField | ResourceField | CollectionField>

CAUTION_MEGA_DANGER_ZONE_arrayExtensions()? ​

ts
optional CAUTION_MEGA_DANGER_ZONE_arrayExtensions(field): 
  | null
| Map<string | symbol, ExtensionDef>;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:367

Retrieve the extension map for an array field

Parameters ​

field ​

ExtensibleField

Returns ​

| null | Map<string | symbol, ExtensionDef>

CAUTION_MEGA_DANGER_ZONE_hasExtension()? ​

ts
optional CAUTION_MEGA_DANGER_ZONE_hasExtension(ext): boolean;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:373

Check if a specific extension has been registered previously

Parameters ​

ext ​
kind ​

"object" | "array"

name ​

string

Returns ​

boolean

CAUTION_MEGA_DANGER_ZONE_objectExtensions()? ​

ts
optional CAUTION_MEGA_DANGER_ZONE_objectExtensions(field, resolvedType): 
  | null
| Map<string | symbol, ExtensionDef>;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:361

Retrieve the extension map for an object field

Parameters ​

field ​

ExtensibleField

resolvedType ​

null | string

Returns ​

| null | Map<string | symbol, ExtensionDef>

CAUTION_MEGA_DANGER_ZONE_registerExtension()? ​

ts
optional CAUTION_MEGA_DANGER_ZONE_registerExtension(extension): void;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:347

Register an extension for either objects or arrays

Parameters ​

extension ​

CAUTION_MEGA_DANGER_ZONE_Extension

Returns ​

void

CAUTION_MEGA_DANGER_ZONE_resourceExtensions()? ​

ts
optional CAUTION_MEGA_DANGER_ZONE_resourceExtensions(resource): 
  | null
| Map<string | symbol, ExtensionDef>;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:353

Retrieve the extension map for a resource

Parameters ​

resource ​

StableRecordIdentifier | { type: string; }

Returns ​

| null | Map<string | symbol, ExtensionDef>

derivation() ​

ts
derivation(field): Derivation;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:126

Returns the derivation registered with the name provided by field.type. Validates that the field is a valid DerivedField.

Parameters ​

field ​

ObjectWithStringTypeProperty | DerivedField

Returns ​

Derivation

doesTypeExist()? ​

ts
optional doesTypeExist(type): boolean;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:71

DEPRECATED - use hasResource instead

Queries whether the SchemaService recognizes type as a resource type

Parameters ​

type ​

string

Returns ​

boolean

Deprecated ​

fields() ​

ts
fields(resource): Map<string, FieldSchema>;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:97

Queries for the fields of a given resource type or resource identity.

Should error if the resource type is not recognized.

Parameters ​

resource ​

StableRecordIdentifier | ObjectWithStringTypeProperty

Returns ​

Map<string, FieldSchema>

hashFn() ​

ts
hashFn(field): HashFn;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:119

Returns the hash function registered with the name provided by field.type. Validates that the field is a valid HashField.

Parameters ​

field ​

ObjectWithStringTypeProperty | HashField

Returns ​

HashFn

hasResource() ​

ts
hasResource(resource): boolean;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:77

Queries whether the SchemaService recognizes type as a resource type

Parameters ​

resource ​

StableRecordIdentifier | ObjectWithStringTypeProperty

Returns ​

boolean

hasTrait() ​

ts
hasTrait(type): boolean;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:83

Queries whether the SchemaService recognizes type as a resource trait

Parameters ​

type ​

string

Returns ​

boolean

registerDerivation() ​

ts
registerDerivation<R, T, FM>(derivation): void;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:172

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 | null | ObjectValue

Parameters ​

derivation ​

Derivation<R, T, FM>

Returns ​

void

registerHashFn() ​

ts
registerHashFn(hashFn): void;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:185

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

Returns ​

void

registerResource() ​

ts
registerResource(schema): void;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:154

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 ​

Schema

Returns ​

void

registerResources() ​

ts
registerResources(schemas): void;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:142

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 ​

Schema[]

Returns ​

void

registerTrait()? ​

ts
optional registerTrait(trait): void;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:214

Registers a Trait for use by resource schemas.

Traits are re-usable collections of fields that can be composed to build up a resource schema. Often they represent polymorphic behaviors a resource should exhibit.

When we finalize a resource, we walk its traits and apply their fields to the resource's fields. All specified traits must be registered by this time or an error will be thrown.

Traits are applied left-to-right, with traits of traits being applied in the same way. Thus for the most part, application of traits is a post-order graph traversal problem.

A trait is only ever processed once. If multiple traits (A, B, C) have the same trait (D) as a dependency, D will be included only once when first encountered by A.

If a cycle exists such that trait A has trait B which has Trait A, trait A will be applied after trait B in production. In development a cycle error will be thrown.

Fields are finalized on a "last wins principle". Thus traits appearing higher in the tree and further to the right of a traits array take precedence, with the resource's fields always being applied last and winning out.

Parameters ​

trait ​

Trait

Returns ​

void

registerTransformation() ​

ts
registerTransformation(transform): void;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:163

Enables registration of a transformation.

The transformation can later be retrieved by the name attached to it's [Type] property.

Parameters ​

transform ​

Transformation

Returns ​

void

relationshipsDefinitionFor()? ​

ts
optional relationshipsDefinitionFor(identifier): RelationshipsSchema;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:335

DEPRECATED - use fields instead

Returns definitions for all properties of the specified resource that are considered "relationships". Generally these are properties that represent a linkage to another resource.

The return value should be a dictionary of key:value pairs where the key is the relationship or property's name and value is an object with at least the following properties:

  • name which should also match the key used in the dictionary.

  • kind which should be either belongsTo or hasMany

  • type which should be the related resource's string "type"

  • options which should be a dictionary allowing any key but with at least the below keys present.

  • options.async a boolean representing whether data for this relationship is typically loaded on-demand.

  • options.inverse a string or null representing the field name / key of the corresponding relationship on the inverse resource.

Additionally the following options properties are optional. See Polymorphic Relationships

  • options.polymorphic a boolean representing whether multiple resource types can be used to satisfy this relationship.
  • options.as a string representing the abstract type that the concrete side of a relationship must specify when fulfilling a polymorphic inverse.

For example, the following Model using @ember-data/model would generate this relationships definition by default:

js
class User extends Model {
  @belongsTo('user', { async: false, inverse: null }) bestFriend;
  @hasMany('user', { async: true, inverse: 'friends' }) friends;
  @hasMany('pet', { async: false, polymorphic: true, inverse: 'owner' }) pets;
}

Which would be returned as

js
{
  bestFriend: {
    name: 'bestFriend',
    kind: 'belongsTo',
    type: 'user',
    options: {
      async: false,
      inverse: null
    }
  },
  friends: {
    name: 'friends',
    kind: 'hasMany',
    type: 'user',
    options: {
      async: true,
      inverse: 'friends'
    }
  },
  pets: {
    name: 'pets',
    kind: 'hasMany',
    type: 'pet',
    options: {
      async: false,
      polymorphic: true,
      inverse: 'owner'
    }
  },
}

Parameters ​

identifier ​

ObjectWithStringTypeProperty | RecordIdentifier

Returns ​

RelationshipsSchema

Deprecated ​

resource() ​

ts
resource(resource): Schema;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:132

Returns the schema for the provided resource type.

Parameters ​

resource ​

StableRecordIdentifier | ObjectWithStringTypeProperty

Returns ​

Schema

resourceHasTrait() ​

ts
resourceHasTrait(resource, trait): boolean;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:89

Queries whether the given resource has the given trait

Parameters ​

resource ​

StableRecordIdentifier | ObjectWithStringTypeProperty

trait ​

string

Returns ​

boolean

resourceTypes() ​

ts
resourceTypes(): readonly string[];

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:341

Returns all known resource types

Returns ​

readonly string[]

transformation() ​

ts
transformation(field): Transformation;

Defined in: warp-drive-packages/core/declarations/store/-types/q/schema-service.d.ts:112

Returns the transformation registered with the name provided by field.type. Validates that the field is a valid transformable.

Parameters ​

field ​

ObjectWithStringTypeProperty | GenericField | ObjectField | ArrayField

Returns ​

Transformation

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