Parse git log output in C#

A simple example for parsing the output of git log in pure C#.

Getting git log output

Get output of git log --name-status by specifying path of git repo.

    public static string ListShaWithFiles(string path)
    {
        var output = RunProcess(string.Format(" --git-dir={0}/.git --work-tree={1} log --name-status", path.Replace("\\", "/"), path.Replace("\\", "/")));
        return output;
    }

Helper for getting command line output

    private static string RunProcess(string command)
    {
        // Start the child process.
        Process p = new Process();
        // Redirect the output stream of the child process.
        p.StartInfo.UseShellExecute = false;
        p.StartInfo.RedirectStandardOutput = true;
        p.StartInfo.FileName = Config.GitExectuable;
        p.StartInfo.Arguments = command;
        p.Start();
        // Read the output stream first and then wait.
        string output = p.StandardOutput.ReadToEnd();
        p.WaitForExit();
        return output;
    }

Parse output

Basic parse loop for parsing a commit. Will show how to populate next.

        using (var strReader = new StringReader(output))
        {
            do
            {
                var line = strReader.ReadLine();

                if( line.StartsWith("commit ") )
                {
                }

                if ( StartsWithHeader(line) )
                {
                }

                if (string.IsNullOrEmpty(line) )
                {
                    // commit message divider
                }

                if (line.Length > 0 && line[0] == '\t')
                { 
                    // commit message.
                }

                if (line.Length > 1 && Char.IsLetter(line[0]) && line[1] == '\t')
                {
                    // file status
                }
            }
            while (strReader.Peek() != -1);
        }
    }

Helper function to help check if a line is a header.

    private bool StartsWithHeader(string line)
    {
        if( line.Length > 0 && char.IsLetter( line[0] ) )
        {
            var seq = line.SkipWhile( ch => Char.IsLetter(ch) && ch != ':' );
            return seq.FirstOrDefault() == ':';
        }
        return false;
    }

Storing results.

Class for holding commits

public class GitCommit
{
    public GitCommit()
    {
        Headers = new Dictionary<string, string>();
        Files = new List<GitFileStatus>();
        Message = "";
    }

    public Dictionary<string, string> Headers { get; set; }
    public string Sha { get; set; }
    public string Message { get; set; }
    public List<GitFileStatus> Files { get; set; }
}

and File status

public class GitFileStatus
{
    public string Status { get; set; }
    public string File { get; set; }
}

Populating results

        GitCommit commit = null;
        var commits = new List<GitCommit>();
        bool processingMessage = false;
        using (var strReader = new StringReader(output))
        {
            do
            {
                var line = strReader.ReadLine();

                if( line.StartsWith("commit ") )
                {
                    if (commit != null)
                        commits.Add(commit);
                    commit = new GitCommit();
                    commit.Sha = line.Split(' ')[1];
                }

                if ( StartsWithHeader(line) )
                {
                    var header = line.Split(':')[0];
                    var val = string.Join(":",line.Split(':').Skip(1)).Trim();

                    // headers
                    commit.Headers.Add(header, val);
                }

                if (string.IsNullOrEmpty(line) )
                {
                    // commit message divider
                    processingMessage = !processingMessage;
                }

                if (line.Length > 0 && line[0] == '\t')
                { 
                    // commit message.
                    commit.Message += line;
                }

                if (line.Length > 1 && Char.IsLetter(line[0]) && line[1] == '\t')
                {
                    var status = line.Split('\t')[0];
                    var file = line.Split('\t')[1];
                    commit.Files.Add(new GitFileStatus() { Status = status, File = file } );
                }
            }
            while (strReader.Peek() != -1);
        }
        if (commit != null)
            commits.Add(commit);

        return commits;
    }

Run it all and print back results

    string path = @"C:\DEV\github\Codegrams";
    if (args.Length > 0)
        path = args[0];
    var output = GitCommands.ListShaWithFiles(path);

    var parser = new ParseGitLog();
    var commits = parser.Parse(output);

    Console.WriteLine(commits.Count);
    foreach (var commit in commits)
    {
        commit.Print();
    }

Print helper

    public void Print()
    {
        Console.WriteLine("commit " + Sha);
        foreach (var key in Headers.Keys)
        {
            Console.WriteLine(key + ":" + Headers[key]);
        }
        Console.WriteLine();
        Console.WriteLine(Message);
        Console.WriteLine();
        foreach (var file in Files)
        {
            Console.WriteLine(file.Status + "\t" + file.File);
        }
    }