# Migration guide

## v0.14.0

- `Dial()` is replaced by `DialContext()`
  - 🔄Update:
    ```diff
    -cli, err := mqtt.Dial(url)
    +cli, err := mqtt.DialContext(ctx, url)
     if err != nil {
       // error handling
     }
     if _, err := cli.Connect(ctx, ...); err != nil {
       // error handling
     }
    ```
  - 🔄If `mqtt.DialerFunc` is used, update:
    ```diff
    -mqtt.DialerFunc(func() (*mqtt.BaseClient, error) {
    +mqtt.DialerFunc(func(ctx context.Context) (*mqtt.BaseClient, error) {
    ```
  - 🔄If you want to use `mqtt.Dialer` interface of mqtt-go<1.14, wrap dialer by:
    ```go
    &mqtt.NoContextDialer{oldDialer}
    ```

## v0.12.0

- `Dial()` returns `*BaseClient` instead of `ClientCloser`
  - 🔄Update variable type if needed.
- Second argument of `RetryClient.SetClient()` requires `*BaseClient` instead of `ClientCloser`
  - 🔄Store client passed to `SetClient` as `*BaseClient` or convert it by the type assertion like `cli.(*BaseClient)`.
- `Client.Subscribe()` returns resultant subscription information as a first return value
  - 🔄Update:
    ```diff
    -err := cli.Subscribe(...)
    +_, err := cli.Subscribe(...)
    ```