> For the complete documentation index, see [llms.txt](https://t1t.gitbook.io/t1c-js-belfius-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://t1t.gitbook.io/t1c-js-belfius-guide/v2.2.3/core/overview-client-api.md).

# Overview Client API

### Interface Style Choice

All examples below and in the rest of this guide will make use of the **callback-based** interface. For your convenience, we also provide a **Promise-based** interface.

Any call that has a callback parameter can have this callback function omitted and will then return a Promise instead.

## Core Services

```javascript
interface AbstractCore{
    // async
    info(callback:(error:CoreExceptions.RestException, data:any) => void):void;
    infoBrowser(callback:(error:CoreExceptions.RestException, data:any) => void):void;
    readers(callback:(error:CoreExceptions.RestException,data:any)=>void):void;
    pollReaders(secondsToPollReader:number,
                callback:(error:CoreExceptions.RestException,data:any)=>void,
                connectReader:()=>void,
                readerTimeout:()=>void
    ):void;
    pollCardInserted(secondsToPollCard:number,
                     callback:(error:CoreExceptions.RestException,data:any)=>void,
                     connectReader:()=>void,
                     insertCard:()=>void,
                     cardTimeout:()=>void

    ):void;
    readersCardAvailable(callback:(error:CoreExceptions.RestException,data:any)=>void):void;
    readersCardsUnavailable(callback:(error:CoreExceptions.RestException,data:any)=>void):void;
    reader(reader_id:string,callback:(error:CoreExceptions.RestException,data:any)=>void):void;
    plugins(callback:(error:CoreExceptions.RestException,data:any)=>void):void;
    getPubKey(callback:(error:CoreExceptions.RestException,data:any)=>void):void;
    setPubKey(pubkey:any,callback:(error:CoreExceptions.RestException,data:any)=>void):void;
    activate(callback:(error:CoreExceptions.RestException, data:any) => void):void;

    // sync
    getUrl():String;
    infoBrowserSync():any;

    // t1c-lib-info
    version():String;
}
```

## Distribution Service Client

```javascript
interface AbstractDSClient{
    getUrl():String;
    getInfo(callback:(error:CoreExceptions.RestException, data:any) => void):void;
    getJWT(callback:(error:CoreExceptions.RestException, data:any) => void):void;
    getDevice(uuid,callback:(error:CoreExceptions.RestException, data:any) => void):void;
    refreshJWT(callback:(error:CoreExceptions.RestException, data:any) => void):void;
    getPubKey(callback:(error:CoreExceptions.RestException, data:any) => void):void;
    downloadLink(infoBrowser, callback:(error:CoreExceptions.RestException, data:any) => void):void;
    register(info, device_id, callback:(error:CoreExceptions.RestException, data:any) => void):void;
    sync(info, device_id, callback:(error:CoreExceptions.RestException, data:any) => void):void;
}
```

## Generic Interface

```javascript
interface GenericService{
    containerFor(readerId: string, callback?: (error: RestException, data: DataResponse) => void): Promise<DataResponse>
    download(callback?: (error: RestException, data: DownloadLinkResponse) => void): Promise<DownloadLinkResponse>
    dumpData(readerId: string, data: OptionalPin, callback?: (error: RestException, data: DataResponse) => void): Promise<DataResponse>
    readersCanAuthenticate(callback?: (error: RestException, data: CardReadersResponse) => void): Promise<CardReadersResponse>
    authenticate(readerId: string, data: AuthenticateOrSignData, callback?: (error: RestException, data: DataResponse) => void): Promise<DataResponse>
    readersCanSign(callback?: (error: RestException, data: CardReadersResponse) => void): Promise<CardReadersResponse>
    sign(readerId: string, data: AuthenticateOrSignData, callback?: (error: RestException, data: DataResponse) => void): Promise<DataResponse>
    readersCanVerifyPin(callback?: (error: RestException, data: CardReadersResponse) => void): Promise<CardReadersResponse>
    verifyPin(readerId: string, data: OptionalPin, callback?: (error: RestException, data: DataResponse) => void): Promise<DataResponse>
}
```


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