Response

In your interface layer (e.g. in your controllers) you will normally return a result that is some kind of response.

A response need to implement the generic "result" interface `Apply' function.

There are a couple of typical Responses available in Flamingo that you can access through the web.Responder.

The following example shows how you can use it and some typical Responder:

type (
    MyController struct {
        responder                    *web.Responder
    }
)


// Inject dependencies
func (mc *MyController) Inject(
    responder *web.Responder
) {
    cc.responder = responder
}


func (mc *MyController) MyAction(ctx context.Context, r *web.Request) web.Result {
    // Render response to render a template and optional pass template data. It is using the reigstered template enginge.
    mc.responder.Render("template",data)
    //Data response  - e.g. to return JSON
    mc.responder.Data(data)
    //Redirect to the given URL
    mc.responder.URLRedirect(url)
    //Redirect to a Flamingo handler (see Routing)
    mc.responder.RouteRedirect("flamingo.handler")
}

HTTP Caching

In a controller you can also set the HTTP Cache directives on the Default Response.

You can do this by using the CacheDirectiveBuilder Helper like this:

    response := cc.responder.Render("checkout/review", viewData)
    response.CacheDirectives = web.NewCacheDirectiveBuilder().SetIsReusable(false).Build()
    return response

The CacheDirectiveBuilder is build around this decision flow:

The image is taken from https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/http-caching?hl=de

Default Strategy

You can add the CacheStrategy Filter to your project. This filter will apply a default CacheStrategy for GET requests, if no CacheDirectives are set by the controller.

To add this filter, just add the Module to your bootstrap like this:

import (
    ...
    "flamingo.me/flamingo/v3/framework/web/filter"
    ...
)


func main() {
    ...
    ... config.NewArea(
        "root",
        []dingo.Module{
            ...
            new(filter.DefaultCacheStrategyModule),
            ...
}

flamingo:
  web:
    filter:
      cachestrategy:
        default:
          revalidateEachTime: true
          isReusable: true