ASP.NET MVC Subprocess Return values

Question

I wrote code like that

public void GitConnectAndFetch()
{   
    try
    {
        ProcessStartInfo startInfo = new ProcessStartInfo("git.exe");
        startInfo.UseShellExecute = false;                
        startInfo.WorkingDirectory = projectPath;                
        startInfo.RedirectStandardInput = true;
        startInfo.RedirectStandardOutput = true;
        startInfo.Arguments = "branch -a";
        Process process = new Process();
        process.StartInfo = startInfo;
        process.Start();
        string branchname = "";
        List<SelectListItem> ddgit = new List<SelectListItem>();
        while (process.StandardOutput.Peek() >= 0)
        {
            branchname = process.StandardOutput.ReadLine().Trim();
            if (branchname.Trim().StartsWith("remotes/origin/"))
            {                       
                ddgit.Add(new SelectListItem { Text = branchname.ToString().Replace("remotes/origin/",""), Value = branchname.ToString() });
            }
        }
        if (ddgit.Count == 0) ddgit.Add(new SelectListItem() { Text = "", Value = "" });
        process.WaitForExit();
        ViewBag.Branchlist = ddgit;
    }
    catch (Exception ex)
    {
        localLog(ex.Message);
        localLog(ex.StackTrace);
    }
}

[HttpGet]
public ActionResult Main()        
{
    GitConnectAndFetch();
    return View();
}

And I called it again after the post

[HttpPost]
public ActionResult Otomasyon(FormCollection form)
{
    GitConnectAndFetch();                    
    return View();
}

I think subprocess is working slowly and I'm calling it twice to fill the dropdown list on my mainpage, how can I make it run for once to close.

Answer 1

If you aren't expecting different values, then I would just cache the value of ddgit and if that cache exists, return it instead of executing the process.

Answer 2

First of all, method GitConnectAndFetch has side effects (setting data into ViewBag), this is not good. Transform it to pure function, that returns SomeBranchItem[].

Secondary, cache the result of GitConnectAndFetch. You may implement it via setting method's result into one private static field A and current timestamp into second static field B. Then on every request you should compare current timestamp and timestamp from field B to determine whether you can use cached data from A as result.