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# Data Services
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NgRx data services generation schematic that creates data services integrating with @ngrx/data for entity-based data management with automatic HTTP operations.
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## Capabilities
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### Data Schematic
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Generates data services with @ngrx/data integration for automated entity management and HTTP operations.
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```bash
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# Basic data service
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ng generate @ngrx/schematics:data User
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```
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```typescript { .api }
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interface DataSchema {
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  name: string;
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  path?: string;
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  project?: string;
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  flat?: boolean;
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}
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```
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### Generated Data Service
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Creates entity data service with automatic CRUD operations:
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```typescript
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// Generated data service
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import { Injectable } from '@angular/core';
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import { EntityCollectionServiceBase, EntityCollectionServiceElementsFactory } from '@ngrx/data';
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@Injectable()
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export class UserDataService extends EntityCollectionServiceBase<User> {
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  constructor(serviceElementsFactory: EntityCollectionServiceElementsFactory) {
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    super('User', serviceElementsFactory);
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  }
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}
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```
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### Entity Metadata Configuration
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Configures entity metadata for @ngrx/data:
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```typescript
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// Entity metadata
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import { EntityMetadataMap } from '@ngrx/data';
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export const entityMetadata: EntityMetadataMap = {
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  User: {
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    selectId: (user: User) => user.id,
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    sortComparer: (a: User, b: User) => a.name.localeCompare(b.name)
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  }
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};
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```
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### HTTP Data Service
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Custom HTTP data service for specialized operations:
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```typescript
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// Custom HTTP data service
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import { Injectable } from '@angular/core';
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import { DefaultDataService, HttpUrlGenerator } from '@ngrx/data';
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import { HttpClient } from '@angular/common/http';
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import { Observable } from 'rxjs';
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@Injectable()
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export class UserHttpDataService extends DefaultDataService<User> {
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  constructor(http: HttpClient, httpUrlGenerator: HttpUrlGenerator) {
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    super('User', http, httpUrlGenerator);
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  }
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  // Custom methods
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  searchUsers(query: string): Observable<User[]> {
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    return this.http.get<User[]>(`${this.entitiesUrl}/search?q=${query}`);
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  }
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}
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```