Revel框架中的缓存失效

Question

I'm looking for a way to invalidate cached static content upon version change. Preferably using commit id to invalidate. Is there anyway to do this in revel framework ?

I would prefer if its automatic but I could live with updating it each time if its a single place I have to edit.

The current strategy I have is changing the name of the static content route to include version but this requires several changes. In places that feel unnatural, for instance in the routing file.

Answer 1

You could do it manually via a config variable and an intercept method.

resourceversion.go

Create this file in your controllers folder:

package controllers

import (
    "github.com/revel/revel"
)

// interceptor method, called before every request. 
// Sets a template variable to the resourceVersion read from app.conf
func SetVersion(c *revel.Controller) revel.Result {
    c.RenderArgs["resourceVersion"] = revel.Config.StringDefault("resourceVersion", "1")
    return nil
}

init.go

In the init() method, append this line:

revel.InterceptMethod(controllers.SetVersion, revel.BEFORE)

templates

In your templates, where you want to use the resource version:

<link rel="stylesheet" type="text/css" href="/public/css/style.css?{{.resourceVersion}}">

app.conf

And finally, the place you will update it - add this line above the dev section to apply to dev and prod, or have a different one in each, whatever suits.

resourceVersion=20150716

I guess you could create a script as part of your build and release process that would automatically edit this config variable.