Go 1.11 has reached end of support and will be deprecated on January 31, 2026. After deprecation, you won't be able to deploy Go 1.11 applications, even if your organization previously used an organization policy to re-enable deployments of legacy runtimes. Your existing Go 1.11 applications will continue to run and receive traffic after their deprecation date . We recommend that you migrate to the latest supported version of Go .

A Go Task Queue Example

This example creates an app that displays an HTML form. You enter a string into the dialog box and click Add . The app counts the number of times that you enter any string in this way.

The app does these things:

When you click Add , the form uses an HTTP POST request to send the string to the app which is running on App Engine. There the app bundles the string into a task and sends it to the default queue.
The queue forwards the task to an included task handler, mapped to the URL /worker , which asynchronously writes the string to a datastore.
Sending an HTTP GET request displays a list of the strings you have entered and the number of times you have Add ed each string, either by typing it or by clicking on it in the dropdown box.

To deploy this app to App Engine:

Copy the following into a file named queue.yaml . This changes the rate at which tasks will be processed from the default 5 per second to 3 per second.
```
  queue 
 : 
 - 
  
 name 
 : 
  
 default 
  
 rate 
 : 
  
 3/s 
 
```

In the same directory, copy the following into a file named as you like (ending in .go ). This is the application code, including the task handler.

  package 
  
 counter 
 import 
  
 ( 
  
 "html/template" 
  
 "net/http" 
  
 "google.golang.org/appengine" 
  
 "google.golang.org/appengine/datastore" 
  
 "google.golang.org/appengine/log" 
  
 "google.golang.org/appengine/taskqueue" 
 ) 
 func 
  
 init 
 () 
  
 { 
  
 http 
 . 
 HandleFunc 
 ( 
 "/" 
 , 
  
 handler 
 ) 
  
 http 
 . 
 HandleFunc 
 ( 
 "/worker" 
 , 
  
 worker 
 ) 
 } 
 type 
  
 Counter 
  
 struct 
  
 { 
  
 Name 
  
 string 
  
 Count 
  
 int 
 } 
 func 
  
 handler 
 ( 
 w 
  
 http 
 . 
 ResponseWriter 
 , 
  
 r 
  
 * 
 http 
 . 
 Request 
 ) 
  
 { 
  
 ctx 
  
 := 
  
 appengine 
 . 
 NewContext 
 ( 
 r 
 ) 
  
 if 
  
 name 
  
 := 
  
 r 
 . 
 FormValue 
 ( 
 "name" 
 ); 
  
 name 
  
 != 
  
 "" 
  
 { 
  
 t 
  
 := 
  
 taskqueue 
 . 
 NewPOSTTask 
 ( 
 "/worker" 
 , 
  
 map 
 [ 
 string 
 ][] 
 string 
 { 
 "name" 
 : 
  
 { 
 name 
 }}) 
  
 if 
  
 _ 
 , 
  
 err 
  
 := 
  
 taskqueue 
 . 
 Add 
 ( 
 ctx 
 , 
  
 t 
 , 
  
 "" 
 ); 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 http 
 . 
 Error 
 ( 
 w 
 , 
  
 err 
 . 
 Error 
 (), 
  
 http 
 . 
 StatusInternalServerError 
 ) 
  
 return 
  
 } 
  
 } 
  
 q 
  
 := 
  
 datastore 
 . 
 NewQuery 
 ( 
 "Counter" 
 ) 
  
 var 
  
 counters 
  
 [] 
 Counter 
  
 if 
  
 _ 
 , 
  
 err 
  
 := 
  
 q 
 . 
 GetAll 
 ( 
 ctx 
 , 
  
& counters 
 ); 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 http 
 . 
 Error 
 ( 
 w 
 , 
  
 err 
 . 
 Error 
 (), 
  
 http 
 . 
 StatusInternalServerError 
 ) 
  
 return 
  
 } 
  
 if 
  
 err 
  
 := 
  
 handlerTemplate 
 . 
 Execute 
 ( 
 w 
 , 
  
 counters 
 ); 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 http 
 . 
 Error 
 ( 
 w 
 , 
  
 err 
 . 
 Error 
 (), 
  
 http 
 . 
 StatusInternalServerError 
 ) 
  
 return 
  
 } 
  
 // OK 
 } 
 func 
  
 worker 
 ( 
 w 
  
 http 
 . 
 ResponseWriter 
 , 
  
 r 
  
 * 
 http 
 . 
 Request 
 ) 
  
 { 
  
 ctx 
  
 := 
  
 appengine 
 . 
 NewContext 
 ( 
 r 
 ) 
  
 name 
  
 := 
  
 r 
 . 
 FormValue 
 ( 
 "name" 
 ) 
  
 key 
  
 := 
  
 datastore 
 . 
 NewKey 
 ( 
 ctx 
 , 
  
 "Counter" 
 , 
  
 name 
 , 
  
 0 
 , 
  
 nil 
 ) 
  
 var 
  
 counter 
  
 Counter 
  
 if 
  
 err 
  
 := 
  
 datastore 
 . 
  Get 
 
 ( 
 ctx 
 , 
  
 key 
 , 
  
& counter 
 ); 
  
 err 
  
 == 
  
 datastore 
 . 
  ErrNoSuchEntity 
 
  
 { 
  
 counter 
 . 
 Name 
  
 = 
  
 name 
  
 } 
  
 else 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 log 
 . 
  Errorf 
 
 ( 
 ctx 
 , 
  
 "%v" 
 , 
  
 err 
 ) 
  
 return 
  
 } 
  
 counter 
 . 
 Count 
 ++ 
  
 if 
  
 _ 
 , 
  
 err 
  
 := 
  
 datastore 
 . 
 Put 
 ( 
 ctx 
 , 
  
 key 
 , 
  
& counter 
 ); 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 log 
 . 
  Errorf 
 
 ( 
 ctx 
 , 
  
 "%v" 
 , 
  
 err 
 ) 
  
 } 
 } 
 var 
  
 handlerTemplate 
  
 = 
  
 template 
 . 
 Must 
 ( 
 template 
 . 
 New 
 ( 
 "handler" 
 ). 
 Parse 
 ( 
 handlerHTML 
 )) 
 const 
  
 handlerHTML 
  
 = 
  
 ` 
{{range .} } 
< p>{{.Name}}: {{.Count}}</p> 
{{end} } 
< p>Start a new counter:</p> 
< form action="/" method="POST" 
>
< input type="text" name="name" 
>
< input type="submit" value="Add" 
>
< /form 
> `

In the same directory, copy the following into a file named app.yaml . This configures your application for App Engine:

  runtime 
 : 
  
 go 
 api_version 
 : 
  
 go1 
 handlers 
 : 
 - 
  
 url 
 : 
  
 /worker/.* 
  
 script 
 : 
  
 _go_app 
  
 login 
 : 
  
 admin 
 - 
  
 url 
 : 
  
 /.* 
  
 script 
 : 
  
 _go_app

Make sure you have a Google Cloud Platform project with an App Engine app prepared and that you have initialized and configured the gcloud command for that project.
Use the gcloud app deploy command to deploy the app to App Engine.
See the app in action by using the gcloud app browse command.

A Go Task Queue Example Stay organized with collections Save and categorize content based on your preferences.

A Go Task Queue Example