Home → Suggestions →

Generic wrapper for retry

• Edit

Sanemat

10 Sep, 2015 04:01 PM

I'm a nodejs user, I met a lot of network error during npm install.
I hope a generic wrapper for retry.

nuget restore has nuge-restore.cmd. nuget#restore-with-retries But this is only for nuget restore.

I copied and pasted windows_retry.cmd and Execute-With-Retry.ps1. I use this.

I'm not familiar with cmd and powershell yet, so I hope appveyor provides a retry command. What do you think about a generic wrapper for retry?

Travis-ci has travis_retry command.

1. 1 Posted by Chris on 09 Aug, 2016 03:14 PM

   

   +1, would also like this.

   I found this example code, am thinking of adding it to my appveyor:

   https://blogs.endjin.com/2014/07/how-to-retry-commands-in-powershell/

   But I don't completely understand it :-/

   function Retry-Command
   {
       param (
       [Parameter(Mandatory=$true)][string]$command,
       [Parameter(Mandatory=$true)][hashtable]$args,
       [Parameter(Mandatory=$false)][int]$retries = 5,
       [Parameter(Mandatory=$false)][int]$secondsDelay = 2
       )
       
       # Setting ErrorAction to Stop is important. This ensures any errors that occur in the command are
       # treated as terminating errors, and will be caught by the catch block.
       $args.ErrorAction = "Stop"
       
       $retrycount = 0
       $completed = $false

       while (-not $completed) {
           try {
               & $command @args
               Write-Verbose ("Command [{0}] succeeded." -f $command)
               $completed = $true
           } catch {
               if ($retrycount -ge $retries) {
                   Write-Verbose ("Command [{0}] failed the maximum number of {1} times." -f $command, $retrycount)
                   throw
               } else {
                   Write-Verbose ("Command [{0}] failed. Retrying in {1} seconds." -f $command, $secondsDelay)
                   Start-Sleep $secondsDelay
                   $retrycount++
               }
           }
       }
   }

   • Edit

2. 2 Posted by Ilya Finkelshte... on 09 Aug, 2016 04:12 PM

   

   Hi Chris,

   We actually already have appveyor-retry command. Please give it a try.
   Please note that to call npm, now you need to use the following syntax: appveyor-retry call npm install
   We understand that it is not obvious, and fix is on its way, in a few days you will be able to use just: appveyor-retry npm install

   Thank you,
   Ilya.

   • Edit

3. 3 Posted by Sanemat on 20 Aug, 2016 12:53 AM

   

   Hi Ilya,

   I have a question.
   I try to do below, but this does not work fine.

   environment:
     matrix:
     - nodejs_version: 4
   
   install:
   - ps: appveyor-retry Install-Product node $env:nodejs_version
   

   This brings error:
   

   appveyor-retry : 'Install-Product' is not recognized as an internal or external command,
   

   https://ci.appveyor.com/project/sanemat/generator-nm5/build/1.0.221...
   Do you have any suggestions?

   • Edit

4. 4 Posted by Ilya Finkelshte... on 20 Aug, 2016 10:25 PM

   

   Please use - cmd: appveyor-retry powershell Install-Product node $env:nodejs_version
   This is because appveyor-retry is cmd batch, which expects some exe to be called, not PowerShell function (which install-product is). Sorry for confusion.
   --ilya.

   • Edit

5. Ilya Finkelshteyn closed this discussion on 25 Aug, 2018 02:08 AM.