Based on https://www.npmjs.com/package/@ouato/nestjs-express-cassandra
With support columns name mapping

## Installation

```bash
$ npm i --save @cyber-rom/nestjs-scylladb
```

## Usage

Import `ScyllaModule`:

```typescript
@Module({
  imports: [
    ScyllaModule.forRoot({...})
  ],
  providers: []
})
export class AppModule {}
```

## Async options

Quite often you might want to asynchronously pass your module options instead of passing them beforehand. In such case, use registerAsync() method, that provides a couple of various ways to deal with async data.

**1. Use factory**

```typescript
ScyllaModule.forRootAsync({
  useFactory: () => ({...}),
})
```

Obviously, our factory behaves like every other one (might be `async` and is able to inject dependencies through `inject`).

```typescript
ScyllaModule.forRootAsync({
    imports: [ConfigModule],
    useFactory: (configService: ConfigService) => configService.getDbConfig(),
    inject: [ConfigService],
});
```

**2. Use class**

```typescript
ScyllaModule.forRootAsync({
    useClass: ConfigService,
});
```

Above construction will instantiate `ConfigService` inside `ScyllaModule` and will leverage it to create options object.

```typescript
class ConfigService implements ScyllaOptionsFactory {
  createScyllaOptions(): ScyllaModuleOptions {
    return {...};
  }
}
```

**3. Use existing**

```typescript
ScyllaModule.forRootAsync({
    imports: [ConfigModule],
    useExisting: ConfigService,
});
```

It works the same as `useClass` with one critical difference - `ScyllaModule` will look up imported modules to reuse already created ConfigService, instead of instantiating it on its own.

## ORM Options

```typescript
import {Entity, Column} from '@cyber-rom/nestjs-scylladb';

@Entity({
    table_name: 'photo',
    key: ['id'],
})
export class PhotoEntity {
    @Column({
        type: 'uuid',
        default: {$db_function: 'uuid()'},
    })
    id: any;

    @Column({
        name: 'photo_name',
        type: 'text',
    })
    name: string;
}
```

Let's have a look at the `PhotoModule`

```typescript
import {Module} from '@nestjs/common';
import {ScyllaModule} from '@cyber-rom/nestjs-scylladb';
import {PhotoService} from './photo.service';
import {PhotoController} from './photo.controller';
import {PhotoEntity} from './photo.entity';

@Module({
    imports: [ScyllaModule.forFeature([PhotoEntity])],
    providers: [PhotoService],
    controllers: [PhotoController],
})
export class PhotoModule {}
```

This module uses `forFeature()` method to define which entities shall be registered in the current scope. Thanks to that we can inject the `PhotoEntity` to the `PhotoService` using the `@InjectModel()` decorator:

```typescript
import {Injectable} from '@nestjs/common';
import {InjectModel, BaseModel} from '@cyber-rom/nestjs-scylladb';
import {PhotoEntity} from './photo.entity';

@Injectable()
export class PersonService {
    constructor(
        @InjectModel(PhotoEntity)
        private readonly photoEntity: BaseModel<PhotoEntity>,
    ) {}

    getByName(name: string): Promise<PhotoEntity> {
        return this.photoEntity.findOneAsync({name: name}, {raw: true});
    }
}
```

**Using Column Decorators:**
To auto-generate uuid/timeuuid column, you need to decorate an entity's properties you want to make into an auto-generated
uuid/timeuuid column with a `@GeneratedUUidColumn` decorator.

```typescript
import {Entity, Column, GeneratedUUidColumn} from '@cyber-rom/nestjs-scylladb';

@Entity({
    table_name: 'photo',
    key: ['id'],
})
export class PhotoEntity {
    @GeneratedUUidColumn()
    id: any;

    @GeneratedUUidColumn('timeuuid')
    time_id: any;

    @Column({
        type: 'text',
    })
    name: string;
}
```

To auto-generate createdDate/updatedDate column, you need to decorate an entity's properties you want to make into an auto-generated
createdDate/updatedDate column with a `@CreateDateColumn` or `@UpdateDateColumn` decorator (not combine with `@Column` decorator).

To index a column, you need to decorate an entity's properties you want to index with a `@IndexColumn` decorator.

To auto-generate version column, you need to decorate an entity's properties you want to make into an auto-generated
version column with a `@VersionColumn` decorator (not combine with `@Column` decorator).

```typescript
import {
    Column,
    Entity,
    IndexColumn,
    VersionColumn,
    UpdateDateColumn,
    CreateDateColumn,
    GeneratedUUidColumn,
} from '@cyber-rom/nestjs-scylladb';

@Entity({
    table_name: 'photo',
    key: ['id'],
})
export class PhotoEntity {
    @GeneratedUUidColumn()
    id: any;

    @GeneratedUUidColumn('timeuuid')
    time_id: any;

    @Column({
        type: 'text',
    })
    @IndexColumn()
    name: string;

    @CreateDateColumn()
    created_at: Date;

    @UpdateDateColumn()
    updated_at: Date;

    @VersionColumn()
    __v1: any;
}
```

**Using Hook Function Decorators:**
An entity of express-cassandra support multiple hook function. For more details [see](https://express-cassandra.readthedocs.io/en/stable/management/#hook-functions).

To create hook function in an entity use `@BeforeSave`, `@AfterSave`, `@BeforeUpdate`, `@AfterUpdate`, `@BeforeDelete`, `@AfterDelete` decorators.

```typescript
import {
    Entity,
    Column,
    AfterSave,
    BeforeSave,
    AfterUpdate,
    AfterDelete,
    BeforeDelete,
    BeforeUpdate,
    GeneratedUUidColumn,
} from '@cyber-rom/nestjs-scylladb';

@Entity({
    table_name: 'photo',
    key: ['id'],
})
export class PhotoEntity {
    @GeneratedUUidColumn()
    id: any;

    @GeneratedUUidColumn('timeuuid')
    time_id: any;

    @BeforeSave()
    beforeSave(instance: this, options: any) {}

    @AfterSave()
    afterSave(instance: this, options: any) {}

    @BeforeUpdate()
    beforeUpdate(query: any, updateValues: any, options: any) {}

    @AfterUpdate()
    afterUpdate(query: any, updateValues: any, options: any) {}

    @BeforeDelete()
    beforeDelete(query: any, options: any) {}

    @AfterDelete()
    afterDelete(query: any, options: any) {}
}
```

## Using Repository

```typescript
import {Module} from '@nestjs/common';
import {ScyllaModule} from '@cyber-rom/nestjs-scylladb';
import {PhotoService} from './photo.service';
import {PhotoController} from './photo.controller';
import {PhotoEntity} from './photo.entity';

@Module({
    imports: [ScyllaModule.forFeature([PhotoEntity])],
    providers: [PhotoService],
    controllers: [PhotoController],
})
export class PhotoModule {}
```

```typescript
import {Injectable} from '@nestjs/common';
import {InjectRepository, Repository} from '@cyber-rom/nestjs-scylladb';
import {PhotoEntity} from './photo.entity';
import {Observable} from 'rxjs';

@Injectable()
export class PersonService {
    constructor(
        @InjectRepository(PhotoEntity)
        private readonly photoRepository: Repository<PhotoEntity>,
    ) {}

    getById(id: id): Observable<PhotoEntity> {
        return this.photoRepository.findOne({id});
    }
}
```

## Using Custom Repository

Let's create a repository:

```typescript
import {Repository, EntityRepository} from '@cyber-rom/nestjs-scylladb';
import {PhotoEntity} from './photo.entity';
import {Observable} from 'rxjs';

@EntityRepository(PhotoEntity)
export class PhotoRepository extends Repository<PhotoEntity> {
    findById(id: any): Observable<PhotoEntity> {
        return this.findOne({id: id});
    }
}
```

Let's have a look at the `PhotoModule`:

```typescript
import {Module} from '@nestjs/common';
import {ScyllaModule} from '@cyber-rom/nestjs-scylladb';

import {PhotoController} from './photo.controller';
import {PhotoRepository} from './photo.repository';
import {PhotoService} from './photo.service';
import {PhotoEntity} from './photo.entity';

@Module({
    imports: [ScyllaModule.forFeature([PhotoEntity, PhotoRepository])],
    providers: [PhotoService],
    controllers: [PhotoController],
})
export class PhotoModule {}
```

Now let's use `PhotoRepository` in `PhotoService`:

```typescript
import {Observable} from 'rxjs';
import {Injectable} from '@nestjs/common';
import {InjectRepository} from '@cyber-rom/nestjs-scylladb';

import {PhotoRepository} from './photo.repository';
import {PhotoEntity} from './photo.entity';

@Injectable()
export class PersonService {
    constructor(
        @InjectRepository(PhotoRepository)
        private readonly photoRepository: PhotoRepository,
    ) {}

    getById(id: any): Observable<PhotoEntity> {
        return this.photoRepository.findById(id);
    }
}
```

Injecting connection:

```typescript
import {Observable} from 'rxjs';
import {Injectable} from '@nestjs/common';
import {InjectRepository, InjectConnection} from '@cyber-rom/nestjs-scylladb';

import {PhotoRepository} from './photo.repository';
import {PhotoEntity} from './photo.entity';

@Injectable()
export class PersonService {
    constructor(
        @InjectConnection()
        private readonly connection: Connection,
        @InjectRepository(PhotoRepository)
        private readonly photoRepository: PhotoRepository,
    ) {}

    getById(id: any): Observable<PhotoEntity> {
        return this.photoRepository.findById(id);
    }
}
```

## Using Elassandra

Express cassandra support `Elassandra`. For more details [see](https://express-cassandra.readthedocs.io/en/stable/elassandra/).

```typescript
@Module({
  imports: [
    ScyllaModule.forRoot({
      clientOptions: {
        // omitted other options for clarity
      },
      ormOptions: {
        // omitted other options for clarity
        migration: 'alter',
        manageESIndex: true,
      }
    })
  ],
  providers: [] // [...]
})
export class AppModule {}
```

```typescript
import {Entity, Column} from '@cyber-rom/nestjs-scylladb';

@Entity<PhotoEntity>({
    table_name: 'photo',
    key: ['id'],
    es_index_mapping: {
        discover: '.*',
        properties: {
            name: {
                type: 'string',
                index: 'analyzed',
            },
        },
    },
})
export class PhotoEntity {
    @Column({
        type: 'uuid',
        default: {$db_function: 'uuid()'},
    })
    id: any;

    @Column({
        type: 'text',
    })
    name: string;
}
```

```typescript
import {Module} from '@nestjs/common';
import {ScyllaModule} from '@cyber-rom/nestjs-scylladb';

import {PhotoController} from './photo.controller';
import {PhotoService} from './photo.service';
import {PhotoEntity} from './photo.entity';

@Module({
    imports: [ScyllaModule.forFeature([PhotoEntity])],
    providers: [PhotoService],
    controllers: [PhotoController],
})
export class PhotoModule {}
```

```typescript
import {Injectable} from '@nestjs/common';
import {InjectModel, BaseModel} from '@cyber-rom/nestjs-scylladb';

import {PhotoEntity} from './photo.entity';

@Injectable()
export class PersonService {
    constructor(
        @InjectModel(PhotoEntity)
        private readonly photoEntity: BaseModel<PhotoEntity>,
    ) {}

    searchName(name: string): Promise<any> {
        return new Promise((resolve, reject) => {
            this.catModel.search({q: `name:${name}`}, (err, response) => {
                if (err) {
                    return reject(err);
                } else {
                    return response(response);
                }
            });
        });
    }
}
```