Response caching uses HTTP headers for all configuration. You can add request headers like `Cache-Control: max-stale=3600` and OkHttp's cache will honor them. Your webserver configures how long responses are cached with its own response headers, like `Cache-Control: max-age=9600`. There are cache headers to force a cached response, force a network response, or force the network response to be validated with a conditional GET.

XML error response for this API is similar to [AWS STS AssumeRole](https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html#API_AssumeRole_Errors)

## Sample `POST` Request

```
http://minio:9000/?Action=AssumeRole&DurationSeconds=3600&Version=2011-06-15&Policy={"Version":"2012-10-17","Statement":[{"Sid":"Stmt1","Effect":"Allow","Action":"s3:*","Resource":"arn:aws:s3:::*"}]}&AUTHPARAMS
```

## Sample Response

```

pkg syscall (darwin-arm64), const B76800 = 76800
pkg syscall (darwin-arm64), const B76800 ideal-int
pkg syscall (darwin-arm64), const B9600 = 9600
pkg syscall (darwin-arm64), const B9600 ideal-int
pkg syscall (darwin-arm64), const BIOCFLUSH = 536887912
pkg syscall (darwin-arm64), const BIOCFLUSH ideal-int
pkg syscall (darwin-arm64), const BIOCGBLEN = 1074020966
pkg syscall (darwin-arm64), const BIOCGBLEN ideal-int

    keepalive_timeout  65;

    # include /etc/nginx/conf.d/*.conf;

    upstream minio {
        server minio1:9000;
        server minio2:9000;
        server minio3:9000;
        server minio4:9000;
        server minio5:9000;
        server minio6:9000;
        server minio7:9000;
        server minio8:9000;
    }

    upstream console {
        ip_hash;
        server minio1:9001;
        server minio2:9001;

        "instance": "localhost:9000",
        "job": "minio-job-node",
        "pool": "0",
        "server": "127.0.0.1:9000",
        "set": "0",
        "severity": "critical"
      },
      "annotations": {
        "description": "MinIO instance 127.0.0.1:9000 of job minio-job has tolerance <=0 for more than 5 minutes.",
        "summary": "Instance 127.0.0.1:9000 unable to tolerate node failures"
      },

    upstream minio {
        server minio1:9000;
        server minio2:9000;
        server minio3:9000;
        server minio4:9000;
    }

    upstream console {
        ip_hash;
        server minio1:9001;
        server minio2:9001;
        server minio3:9001;
        server minio4:9001;
    }

    server {
        listen       9000;
        listen  [::]:9000;
        server_name  localhost;

pkg syscall (freebsd-arm64), const B76800 ideal-int
pkg syscall (freebsd-arm64), const B921600 = 921600
pkg syscall (freebsd-arm64), const B921600 ideal-int
pkg syscall (freebsd-arm64), const B9600 = 9600
pkg syscall (freebsd-arm64), const B9600 ideal-int
pkg syscall (freebsd-arm64), const BIOCFEEDBACK = 2147762812
pkg syscall (freebsd-arm64), const BIOCFEEDBACK ideal-int
pkg syscall (freebsd-arm64), const BIOCFLUSH = 536887912

    keepalive_timeout  65;

    # include /etc/nginx/conf.d/*.conf;

    upstream minio {
        server minio1:9000;
    }

    upstream console {
        ip_hash;
        server minio1:9001;
    }

    server {
        listen       9000;
        listen  [::]:9000;
        server_name  localhost;

        # To allow special characters in headers
        ignore_invalid_headers off;

```

## Create a bucket and upload some data

Create a bucket named `functionbucket`
```
mc alias set myminio/ http://localhost:9000 minioadmin minioadmin
mc mb myminio/functionbucket
```

Create a file `testobject` with some test data that will be transformed
```
cat > testobject << EOF

docker-compose.exe pull
docker-compose.exe up
```

or

```sh
docker stack deploy --compose-file docker-compose.yaml minio
```

Distributed instances are now accessible on the host using the Minio CLI on port 9000 and the Minio Web Console on port 9001. Proceed to access the Web browser at <http://127.0.0.1:9001/>. Here 4 MinIO server instances are reverse proxied through Nginx load balancing.

### Notes