v1 Receive messages with delivery attempts (DEPRECATED)

  import 
  
 ( 
  
 "context" 
  
 "fmt" 
  
 "io" 
  
 "time" 
  
 "cloud.google.com/go/pubsub" 
 ) 
 func 
  
 pullMsgsDeadLetterDeliveryAttempt 
 ( 
 w 
  
 io 
 . 
 Writer 
 , 
  
 projectID 
 , 
  
 subID 
  
 string 
 ) 
  
 error 
  
 { 
  
 // projectID := "my-project-id" 
  
 // subID := "my-sub" 
  
 ctx 
  
 := 
  
 context 
 . 
 Background 
 () 
  
 client 
 , 
  
 err 
  
 := 
  
 pubsub 
 . 
  NewClient 
 
 ( 
 ctx 
 , 
  
 projectID 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 return 
  
 fmt 
 . 
 Errorf 
 ( 
 "pubsub.NewClient: %w" 
 , 
  
 err 
 ) 
  
 } 
  
 defer 
  
 client 
 . 
 Close 
 () 
  
 // Receive messages for 10 seconds, which simplifies testing. 
  
 // Comment this out in production, since `Receive` should 
  
 // be used as a long running operation. 
  
 ctx 
 , 
  
 cancel 
  
 := 
  
 context 
 . 
 WithTimeout 
 ( 
 ctx 
 , 
  
 10 
 * 
 time 
 . 
 Second 
 ) 
  
 defer 
  
 cancel 
 () 
  
 sub 
  
 := 
  
 client 
 . 
 Subscription 
 ( 
 subID 
 ) 
  
 err 
  
 = 
  
 sub 
 . 
 Receive 
 ( 
 ctx 
 , 
  
 func 
 ( 
 _ 
  
 context 
 . 
 Context 
 , 
  
 msg 
  
 * 
 pubsub 
 . 
 Message 
 ) 
  
 { 
  
 // When dead lettering is enabled, the delivery attempt field is a pointer to the 
  
 // the number of times the service has attempted to delivery a message. 
  
 // Otherwise, the field is nil. 
  
 if 
  
 msg 
 . 
 DeliveryAttempt 
  
 != 
  
 nil 
  
 { 
  
 fmt 
 . 
 Fprintf 
 ( 
 w 
 , 
  
 "message: %s, delivery attempts: %d" 
 , 
  
 msg 
 . 
 Data 
 , 
  
 * 
 msg 
 . 
 DeliveryAttempt 
 ) 
  
 } 
  
 msg 
 . 
 Ack 
 () 
  
 }) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 return 
  
 fmt 
 . 
 Errorf 
 ( 
 "got error in Receive: %w" 
 , 
  
 err 
 ) 
  
 } 
  
 return 
  
 nil 
 } 
 

  # subscription_id = "your-subscription-id" 
 pubsub 
  
 = 
  
 Google 
 :: 
 Cloud 
 :: 
  Pubsub 
 
 . 
 new 
 subscription 
  
 = 
  
 pubsub 
 . 
 subscription 
  
 subscription_id 
 subscription 
 . 
 pull 
 ( 
 immediate 
 : 
  
 false 
 ) 
 . 
 each 
  
 do 
  
 | 
 message 
 | 
  
 puts 
  
 "Received message: 
 #{ 
 message 
 . 
 data 
 } 
 " 
  
 puts 
  
 "Delivery Attempt: 
 #{ 
 message 
 . 
 delivery_attempt 
 } 
 " 
  
 message 
 . 
 acknowledge! 
 end