source

Documentation

Overview

Package source implements a custom predicate to match routes based on the source IP of a request.

It is similar in function and usage to the header predicate but has explicit support for IP adresses and netmasks to conveniently create routes based on a whole network of adresses, like a company network or something similar.

It is important to note, that this predicate should not be used as the only gatekeeper for secure endpoints. Always use proper authorization and authentication for access control!

To enable usage of this predicate behind loadbalancers or proxies, the X-Forwared-For header is used to determine the source of a request if it is available. If the X-Forwarded-For header is not present or does not contain a valid source address, the source IP of the incoming request is used for matching.

The source predicate supports one or more IP addresses with or without a netmask.

There are two flavors of this predicate Source() and SourceFromLast(). The difference is that Source() finds the remote host as first entry from the X-Forwarded-For header and SourceFromLast() as last entry.

Examples:

// only match requests from 1.2.3.4
example1: Source("1.2.3.4") -> "http://example.org";

// only match requests from 1.2.3.0 - 1.2.3.255
example2: Source("1.2.3.0/24") -> "http://example.org";

// only match requests from 1.2.3.4 and the 2.2.2.0/24 network
example3: Source("1.2.3.4", "2.2.2.0/24") -> "http://example.org";

// same as example3, only match requests from 1.2.3.4 and the 2.2.2.0/24 network
example4: SourceFromLast("1.2.3.4", "2.2.2.0/24") -> "http://example.org";

Index

• Constants
• Variables
• func New() routing.PredicateSpec
• func NewFromLast() routing.PredicateSpec

Constants

const (
	Name     = "Source"
	NameLast = "SourceFromLast"
)

Variables

var InvalidArgsError = errors.New("invalid arguments")

Functions

func New

func New() routing.PredicateSpec

func NewFromLast

func NewFromLast() routing.PredicateSpec