Buffering

The buffering middleware limits the size of requests that can be forwarded to services.

With buffering, Traefik reads the entire request into memory (possibly buffering large requests into disk), and rejects requests that are over a specified size limit.

This can help services avoid large amounts of data (multipart/form-data for example), and can minimize the time spent sending data to a Service

Configuration Examples

Structured (YAML)

# Sets the maximum request body to 2MB
http:
  middlewares:
    limit:
      buffering:
        maxRequestBodyBytes: 2000000

Structured (TOML)

# Sets the maximum request body to 2MB
[http.middlewares]
  [http.middlewares.limit.buffering]
    maxRequestBodyBytes = 2000000

Labels

# Sets the maximum request body to 2MB
labels:
  - "traefik.http.middlewares.limit.buffering.maxRequestBodyBytes=2000000"

Tags

// Sets the maximum request body to 2MB
{
  // ...
  "Tags": [
    "traefik.http.middlewares.test-auth.basicauth.users=test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/,test2:$apr1$d9hr9HBB$4HxwgUir3HP4EsggP/QNo0"
  ]
}

Kubernetes

# Sets the maximum request body to 2MB
apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: limit
spec:
  buffering:
    maxRequestBodyBytes: 2000000

Configuration Options

Field	Description	Default	Required
maxRequestBodyBytes	Maximum allowed body size for the request (in bytes). If the request exceeds the allowed size, it is not forwarded to the Service, and the client gets a 413 (Request Entity Too Large) response.	0	No
memRequestBodyBytes	Threshold (in bytes) from which the request will be buffered on disk instead of in memory with the memRequestBodyBytes option.	1048576	No
maxResponseBodyBytes	Maximum allowed response size from the Service (in bytes). If the response exceeds the allowed size, it is not forwarded to the client. The client gets a 500 (Internal Server Error) response instead.	0	No
memResponseBodyBytes	Threshold (in bytes) from which the response will be buffered on disk instead of in memory with the memResponseBodyBytes option.	1048576	No
retryExpression	Replay the request using retryExpression. More information here.	""	No

retryExpression

The retry expression is defined as a logical combination of the functions below with the operators AND (&&) and OR (||).
At least one function is required:

• Attempts() number of attempts (the first one counts).
• ResponseCode() response code of the Service.
• IsNetworkError() whether the response code is related to networking error.