Using structs and closures for stateful handlers

Due to the sparse signatures of HTTP handler functions, it may seem tricky to add state to a handler. For example, there are a variety of ways to include a database connection. Two approaches to doing this are to pass in the state via closures, which is useful for flexibility on a single handler, or by using a struct.

This recipe will demonstrate both. We'll use a struct controller to store a storage interface and create two routes with a single handler that are modified by an outer function.

Getting ready

Refer to the steps given in the Getting ready section of the Working with web handlers, requests, and ResponseWriters recipe.

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