Package gorilla/sessions provides cookie and filesystem sessions and infrastructure for custom session backends.
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README.md

sessions

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gorilla/sessions provides cookie and filesystem sessions and infrastructure for custom session backends.

The key features are:

  • Simple API: use it as an easy way to set signed (and optionally encrypted) cookies.
  • Built-in backends to store sessions in cookies or the filesystem.
  • Flash messages: session values that last until read.
  • Convenient way to switch session persistency (aka "remember me") and set other attributes.
  • Mechanism to rotate authentication and encryption keys.
  • Multiple sessions per request, even using different backends.
  • Interfaces and infrastructure for custom session backends: sessions from different stores can be retrieved and batch-saved using a common API.

Let's start with an example that shows the sessions API in a nutshell:

	import (
		"net/http"
		"github.com/gorilla/sessions"
	)

	// Note: Don't store your key in your source code. Pass it via an
	// environmental variable, or flag (or both), and don't accidentally commit it
	// alongside your code. Ensure your key is sufficiently random - i.e. use Go's
	// crypto/rand or securecookie.GenerateRandomKey(32) and persist the result.
	var store = sessions.NewCookieStore(os.Getenv("SESSION_KEY"))

	func MyHandler(w http.ResponseWriter, r *http.Request) {
		// Get a session. We're ignoring the error resulted from decoding an
		// existing session: Get() always returns a session, even if empty.
		session, _ := store.Get(r, "session-name")
		// Set some session values.
		session.Values["foo"] = "bar"
		session.Values[42] = 43
		// Save it before we write to the response/return from the handler.
		session.Save(r, w)
	}

First we initialize a session store calling NewCookieStore() and passing a secret key used to authenticate the session. Inside the handler, we call store.Get() to retrieve an existing session or create a new one. Then we set some session values in session.Values, which is a map[interface{}]interface{}. And finally we call session.Save() to save the session in the response.

Important Note: If you aren't using gorilla/mux, you need to wrap your handlers with context.ClearHandler or else you will leak memory! An easy way to do this is to wrap the top-level mux when calling http.ListenAndServe:

	http.ListenAndServe(":8080", context.ClearHandler(http.DefaultServeMux))

The ClearHandler function is provided by the gorilla/context package.

More examples are available on the Gorilla website.

Store Implementations

Other implementations of the sessions.Store interface:

License

BSD licensed. See the LICENSE file for details.