Iterates through tfvars file and replaces values with corresponding values from Octopus Deploy.

replaceTfVars.cs

var varsFile = Octopus.Parameters["tfvarsfile"];
Console.WriteLine("Parsing tfVarsFile: " + varsFile);

if (string.IsNullOrEmpty(varsFile))
    throw new ApplicationException("You must provide a tf vars file location");

if (!File.Exists(varsFile))
    throw new ApplicationException(string.Format("Specified tf vars file, {0}, not found", varsFile));

string tempFile = string.Concat(varsFile, "-temp");

using (var input = File.OpenText(varsFile))
using (var output = new StreamWriter(tempFile))
{
	Console.WriteLine("##octopus[stdout-verbose]");
	string line;
	while (null != (line = input.ReadLine()))
	{
		var equalsIndex = line.IndexOf("=");
		if (equalsIndex < 0)
		{
			output.WriteLine(line);
			continue;
		}
		
		string variableName = line.Substring(0, equalsIndex).Trim();
		Console.WriteLine(string.Format("Got variable name: {0}", variableName));
		
		string value;
		if (Octopus.Parameters.TryGetValue(variableName, out value))
		{
			Console.WriteLine(string.Format("Found matching value {0} for variable {1}: ", value, variableName));
			var replacement = value.StartsWith("[") ? value : string.Format("\"{0}\"", value);
				
			output.WriteLine(string.Format("{0} = {1}", variableName, replacement));
		}
		else
		{
			Console.WriteLine(string.Format("No matching value for variable: {0}", variableName));
			output.WriteLine(line);
		}
	}
}

// Replace the original with the temp
File.Delete(varsFile);
File.Move(tempFile, varsFile);