The retry mechanism is a mechanism that retrys the program after an error occurs during the execution of the program. By restarting the software, reconnecting the network, resending requests, etc., we can reduce errors during the program operation, thereby improving the reliability of the program.
The retry mechanism is usually used in fields such as network communication. For example, when calling a remote interface, the request fails due to network fluctuations and other reasons, so retry is required, so the normal operation rate of the program can be maximized.
Ideas for encapsulating go retry mechanism
The following points need to be considered when encapsulating the go retry mechanism:
Define the maximum number of retry times
Including parameters such as the maximum number of attempts, retry time interval, etc. These parameters can be configured and modified according to actual conditions. For example, when requesting a remote interface, if it still fails after 3 retry, the request should be ended.
Type of error when processing retry
Different errors may be raised for different reasons during retry, so you need to consider handling these errors in the retry mechanism for subsequent attempts.
Define the timeout for the retry mechanism
Timeout time is usually used when requesting remote services. It is called timeout setting. It refers to the time interval waiting for the server to return data. If this time interval exceeds it, an error will be caused. In the retry mechanism, if the server still does not return data after multiple retry, the retry needs to be forced to end within a certain period of time.
Log the retry process
In the retry mechanism, it is necessary to record the results and reasons of each retry, including success and failure, so as to facilitate troubleshooting and subsequent optimization.
Go retry mechanism implementation
The implementation solution of the retry mechanism can be divided into two types: function encapsulation and structure encapsulation
Function encapsulation is a simple way to encapsulate all parameters related to the retry mechanism in the parameters to facilitate the user to call the program, but it lacks advanced features such as logging and function implementation.
Structural encapsulation is another method of encapsulation. It encapsulates parameters related to the retry mechanism in the structure, allowing users to define the structure and modify the parameters in the structure, and can track the status of the retry mechanism.
In this article, we will introduce a retry mechanism using structures for encapsulation, and the code implementation is as follows:
package retry
import (
"time"
)
type Retry struct {
retryCount int // Maximum number of retry retryDelay // Delay between retry retryTimeout // Timeout retry time retryIntervalFunc func(int)
}
type RetriableError struct {
error error
}
func (e RetriableError) Error() string {
return ()
}
// Retry methodfunc (r *Retry) Retry(fn func() error) error {
retryStart := ()
var err error
retryCount := 0
for {
duration := (retryCount)
(duration)
err = fn()
if err == nil {
return nil
}
if _, ok := err.(RetriableError); ok {
if retryCount < -1 {
retryCount++
continue
}
break
}
if ().Before(()) {
break
}
}
return err
}
func New(
retryCount int,
retryDelay ,
retryTimeout ,
retryIntervalFunc func(attempt int) ,
) *Retry {
return &Retry{
retryCount: retryCount,
retryDelay: retryDelay,
retryTimeout: retryTimeout,
retryIntervalFunc: retryIntervalFunc,
}
}
func ExampleRetry() {
r := New(3, 1*, 5*, func(attempt int) {
return
})
err := (func() error {
// Do some work here
return RetriableError{error: ("foo")}
})
if err != nil {
panic(err)
}
}In the above code, we encapsulate the Retry structure. The maximum number of retry times is included in the structure（RetryCount）、RetryDelay、Timeout (RetryTimeout)andRetry the time interval function (RetryIntervalFunc)Four parameters are initialized through the New() method.
where RetryIntervalFunc accepts an attempt counter as a parameter and returns the time interval before the next retry accordingly. The fn function is the function to be retryed, returning an error asRetry methodreturn value.
The Retry method includes an infinite loop in which the fn function is attempted. If the fn function returns nil, method returns nil, if the error is RetriableError, try again, otherwise return an error.
The retry method will wait for the specified delay time (RetryDelay) between each retry, and the delay interval will be calculated in the RetryIntervalFunc function.
Example of using go retry mechanism
In this chapter, we will use the remote API as an example to demonstrate how to use the go retry mechanism.
We will use the retry mechanism to call the remote server and process the original response. Suppose we are using Go to get data from a remote API, we need to process these retry requests. If we still don't get the data after the first five attempts, a "Retry failed" error is returned. Here we ask to wait 1 second before trying and wait up to 5 minutes (300 seconds) before retrying 6 times.
func ExampleRemoteAPICall() {
r := New(5, 1*, 5*, func(attempt int) {
return
})
resp, err := (func() error {
r, err := ("GET", "<>", nil)
if err != nil {
return RetriableError{error: err}
}
client := &{}
resp, err := (r)
if err != nil {
return RetriableError{error: err}
}
if != {
return RetriableError{error: ("Unexpected status code (%v)", )}
}
// If the remote API call is successful, we will return the data. return nil
})This is the end of this article about the detailed explanation of Golang skills for retry mechanism. For more related content of Golang retry mechanism, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!