@targetprocess/tokiny/README.md

Client for easy retrieving access_tokens from Targetprocess Auth service.

## Node.js compatibility
**Node.js 12 or higher is required. For older Node.js versions use [tokiny@^2.0.0.](https://gitlab.tpondemand.net/sdk/tokiny/tree/v2.3.0)**

## Targetprocess Tokiny

JavaScript client for retrieving auth access_tokens by OAuth client credentials flow.

## Features

- Allow easily retrieve access_token from Targetprocess Auth service
- Cache token if specified
- Does not send multiple requests to auth in case of multiple token retrieve attempts occurred in one time. For token requests with same access parameters only on request will be actually made to auth.

## Quick start

To install tokiny use:

```bash
npm install  @targetprocess/tokiny
```

To get new access token from Targetprocess auth:

```typescript
import {createTokenFactory} from "@targetprocess/tokiny";

const tokenFactory = createTokenFactory({
  authUrl: env.AUTH_SERVICE_URI,
  clientId: env.CLIENT_ID,
  clientSecret: env.CLIENT_SECRET
});

const token = await tokenFactory.getToken("scope1 scope2");
```

_createTokenFsactory_ as a parameter expects object of type **IAuthOptions**:

```typescript
interface IAuthOptions {
  authUrl: string; // Auth service url
  clientId: string; // Your service  client id
  clientSecret: string; // Your service client secret
  expirationLimitSeconds?: number; // if useCashe = true, defines a treshold between cached token expiraion, when new token will be retieved. 120 by default
  useCache?: boolean; // Sets if token caching is turned on. true by default
  httpRequestTimeout: number; // Sets http timeout for requests
  retryOptions: IAuthRetryOptions; // Allow to specify auth retry options
  logger?: IAuthLogger; // Allow to enable logging by specifying logger that would be used for logging internal diagnostics messages. Logging is disabled by default
  loggerMessagePrefix?: string; // Allow to specify custom logger messages prefix. "[tokiny] " by default
}
interface IAuthRetryOptions {
  retry: boolean // Should retry. Default false.
  retries?: number // The maximum amount of times to retry the operation. Default is 3.
  factor?: number // The exponential factor to use. Default is 2.
  minTimeout?: number // The number of milliseconds before starting the first retry. Default is 1000.
  maxTimeout?: number // The maximum number of milliseconds between two retries. Default is Infinity.
}
interface IAuthLogger {
  error: LogMethod
  warn: LogMethod
  info: LogMethod
  debug: LogMethod
}
type LogMethod = (msg: string | Error, err?: Error) => void
```

_tokenFactory.getToken_ returns object of type **ITokenSet**:

```typescript
export interface ITokenSet {
  access_token: string; //access_token itself
  expires_at: number; // token expiration time
  type: string; // token type
}
```

Tokiny also exports wrapped over http-fetch object, which expected by generated by nswag client for example. So you had not to set token to Authroization header manually. You can just write smth like this:

```typescript
import {createTokenFactory, httpClientFactory} from "@targetprocess/tokiny";

const tokenFactory = createTokenFactory({
  authUrl: env.AUTH_SERVICE_URI,
  clientId: env.CLIENT_ID,
  clientSecret: env.CLIENT_SECRET
});

const token = await tokenFactory.getToken("scope1 scope2");
const scopes = "scope1 scope2";

const someClient = new SomeClient(
  `http://some_url`,
  httpClientFactory(scopes, tokenFactory, fetch)
);
```

## Release notes

[here](docs/changelog.md)