CacheModifier returns a ResponseModifier that sets a maximum cache header It optionally takes another response modifier that it wraps around and performs first when called.

CreateOSMapsProxy returns a ReverseProxy that modifies requests to add an Ordnance Survey api key and forward them on to the O/S api.

Setup function sets up the api and returns an api.

StringReplaceResponseModifier returns a function that takes in a pointer to a Response object that modifies that response by changing every instance of a string in the body to another string.

API provides a struct to wrap the api around.

Config is a struct that contains configuration values required by the API.