The handler function has this signature.

Sample handler:
```go
    handler :=  func(ctx context.Context, payload []byte, in <-chan []byte, out chan<- []byte) *RemoteErr {
        fmt.Println("Got request with initial payload", p, "from", GetCaller(ctx context.Context))
        fmt.Println("Subroute:", GetSubroute(ctx))
        for {
            select {

## Expected Behavior
<!--- If you're describing a bug, tell us what should happen -->
<!--- If you're suggesting a change/improvement, tell us how it should work -->

## Current Behavior
<!--- If describing a bug, tell us what happens instead of the expected behavior -->
<!--- If suggesting a change/improvement, explain the difference from current behavior -->

## Possible Solution

stale_uploads_expiry            (duration)  set to expire stale multipart uploads older than this values (default: '24h')
stale_uploads_cleanup_interval  (duration)  set to change intervals when stale multipart uploads are expired (default: '6h')
delete_cleanup_interval         (duration)  set to change intervals when deleted objects are permanently deleted from ".trash" folder (default: '5m')

  - New objects inherit the retention settings of the bucket object lock configuration automatically
  - Retention headers can be optionally set while uploading objects
  - Once objects are uploaded PutObjectRetention API can be called to change retention settings
- *MINIO_NTP_SERVER* environment variable can be set to remote NTP server endpoint if system time is not desired for setting retention dates.

## Explore Further

## Creating a hotfix branch

Customers in MinIO are allowed LTS on any release they choose to standardize. Production setups seldom change and require maintenance. Hotfix branches are such maintenance branches that allow customers to operate a production cluster without drastic changes to their deployment.

## Backporting a fix

You can use Helm to update MinIO version in a live release. Assuming your release is named as `my-release`, get the values using the command:

```bash
helm get values my-release > old_values.yaml
```

Then change the field `image.tag` in `old_values.yaml` file with MinIO image tag you want to use. Now update the chart using

```bash
helm upgrade -f old_values.yaml my-release minio/minio
```

## Expected Behavior
<!--- If you're describing a bug, tell us what should happen -->
<!--- If you're suggesting a change/improvement, tell us how it should work -->

## Current Behavior
<!--- If describing a bug, tell us what happens instead of the expected behavior -->
<!--- If suggesting a change/improvement, explain the difference from current behavior -->

## Possible Solution

sftp>
```

## Advanced options

### Change default FTP port

Default port '8021' can be changed via

```
--ftp="address=:3021"
```

### Change FTP passive port range

By default FTP requests OS to give a free port automatically, however you may want to restrict

management of root accounts across sites and the ability to disable root accounts eventually.

However, this means that STS tokens signed previously by root credentials will no longer be valid upon upgrading to the latest version with this change. Please re-generate them as you usually do. Additionally, if site replication is ever removed - the STS tokens will become invalid, regenerate them as you usually do....

## How to test this PR?


## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Optimization (provides speedup with no functional changes)
- [ ] Breaking change (fix or feature that would cause existing functionality to change)

## Checklist:
- [ ] Fixes a regression (If yes, please add `commit-id` or `PR #` here)