Run script on another computer; HTTP server

Assume you want to run some codes or scripts on computer named SERVER from computer named CLIENT. The computers can be on local network or internet or it can be the same computer. CLIENT can be any device that can use the internet (PC, smartphone, etc).
On SERVER computer run code like this. It can be a script or independent program.
//HTTP server. Runs all the time.
HttpServerSession.Listen<HttpServerSessionExamples>();

class HttpServerSessionExamples : HttpServerSession {
	protected override void MessageReceived(HSMessage m, HSResponse r) {
		//Here can be any code. It runs when the HTTP server receives a HTTP request message. Below are examples.
		
		#region simple
		
		//Prevent executing the rest of code without a password.
		Auth((u, p) => p == "password278351");
		
		//Print some properties of the HTTP request message.
		print.it(m.Method, m.TargetPath, m.UrlParameters, m.Text, m.Headers);
		
		//Return some text.
		r.SetContentText("text");
		
		//Several examples of code on CLIENT computer.
		//To make easier to read this recipe, client code examples here are below corresponding server code examples,
		//	in local functions like this. Normally these codes would be in a script on CLIENT computer, not here.
		static void client_example_simple() {
			//Simplest HTTP request.
			internet.http.Get("http://SERVER:4455");
			
			//HTTP request with password (basic authentication).
			internet.http.Get("http://SERVER:4455", auth: ":password278351");
			
			//If server and client are on the same computer, SERVER can be "localhost" or "127.0.0.1" or "[::1]".
			internet.http.Get("http://[::1]:4455");
			
			//Get text returned by MessageReceived.
			string r = internet.http.Get("http://SERVER:4455").Text();
			print.it(r);
		}
		
		#endregion
		
		#region run script
		
		//Examples of how SERVER can process "run script" requests.
		if (m.Method == "GET" && m.TargetPath == "/script.run") {
			try {
				//Without arguments.
				script.run(m.UrlParameters["name"]);
				
				//With 1 argument (in that script it will be args[0]).
				script.run(m.UrlParameters["name"], m.UrlParameters["a0"]);
				
				//Run the script and return its results written with script.writeResult.
				script.runWait(out string res, m.UrlParameters["name"]);
				r.SetContentText(res);
				
				//The scripts must be in current workspace on SERVER computer.
				
				//Or you can place script code in the server script. For example, in separate functions, and let MessageReceived call them.
				//But there are some bad things:
				//-	To apply changes in script code will need to restart the server process.
				//- May be difficult or impossible to stop the script without killing the server process.
				//- A failed script in some cases may kill the server process.
				//- Some bugs in scripts and used libraries may create memory leaks and other mess in the server process.
			}
			catch { r.Status = System.Net.HttpStatusCode.NotFound; }
		}
		
		//Examples of how CLIENT can send "run script" requests.
		static void client_example_run_script() {
			//Run script "Script name.cs" with argument "hello" (in that script it will be args[0]).
			internet.http.Get("http://SERVER:4455/script.run?name=Script+name.cs&a0=hello");
			
			//To URL-encode the script name and arguments can be used internet.urlAppend.
			internet.http.Get(internet.urlAppend("http://SERVER:4455/script.run", "name=Script name.cs", "a0=hello"));
		}
		
		#endregion
		
		#region run script using POST
		
		//Example of how SERVER can process "run script" requests using POST request.
		if (m.Method == "POST" && m.TargetPath == "/script.run") {
			try { script.run(m.Multipart["name"], m.Multipart["a0"]); }
			catch { r.Status = System.Net.HttpStatusCode.NotFound; }
		}
		
		//Example of code on CLIENT computer.
		static void client_example_run_script_post() {
			internet.http.Post("http://SERVER:4455/script.run", internet.formContent(("name", "Script name.cs"), ("a0", "long text")));
		}
		
		#endregion
		
		#region send and run script code
		
		//The editor program can run only scripts that exist in current workspace, and does not have importing API.
		//Workaround: manually create an empty script on SERVER, and let MessageReceived replace its text when CLIENT sends script code.
		//To test this example, at first please create folder "Volatile" in the editor on SERVER computer. Then in it create script "Code-1".
		
		//Example of how SERVER can process "run script" requests when CLIENT sends script code.
		//Receives script code, saves it in an existing script (overwrites), and runs the script.
		Auth((u, p) => p == "password441+k");
		if (m.Method == "POST" && m.TargetPath == "/script.run/code") {
			string file = m.Multipart["file"], code = m.Multipart["code"];
			string fullPath = folders.Workspace + $@"files\Volatile\{file}";
			if (code != filesystem.loadText(fullPath)) filesystem.saveText(fullPath, code);
			script.run($@"\Volatile\{file}");
		}
		
		//Example of code on CLIENT computer.
		static void client_example_run_script_code() {
			var content = internet.formContent(("file", @"Code-1.cs"), ("code", """print.it("test");"""));
			internet.http.Post("http://SERVER:4455/script.run/code", content, auth: ":password441+k");
		}
		
		#endregion
		
		#region pass objects using JSON
		
		//Example of how SERVER can receive and return an object using JSON.
		if (m.Method == "POST" && m.TargetPath == "/json") {
			var point = m.Json<POINT>();
			print.it(point);
			var rect = new RECT(point.x * 2, point.y * 2, 100, 100);
			r.SetContentJson(rect);
		}
		
		//Example of code on CLIENT computer.
		static void client_example_json() {
			var point = new POINT(1, 2);
			var rect = internet.http.Post("http://SERVER:4455/json", internet.jsonContent(point)).Json<RECT>();
			print.it(rect);
		}
		
		//This example uses known types (POINT and RECT), but you can define and use classes or structs for it.
		
		#endregion
		
		#region upload file
		
		//Example of how SERVER can receive a file.
		if (m.Method == "POST" && m.TargetPath == "/files") {
			var v = m.Multipart["file"];
			filesystem.saveBytes(@"C:\Test\HttpServerSession\files\" + v.FileName, v.Content);
		}
		
		//Example of code on CLIENT computer.
		static void client_example_upload_file() {
			internet.http.Post("http://SERVER:4455/files", internet.formContent(("some", "info")).AddFile("file", @"C:\Test\file.txt"));
		}
		
		#endregion
		
		#region download file
		
		//Example of how SERVER can return a file.
		if (m.Method == "GET") {
			var file = m.TargetPath; if (file == "/") file = "index.html";
			file = pathname.combine(@"C:\Test\HttpServerSession", file);
			try {
				r.Content = File.ReadAllBytes(file);
				r.Headers["Content-Type"] = "text/html; charset=utf-8";
			}
			catch { r.Status = System.Net.HttpStatusCode.NotFound; }
		}
		
		//Example of code on CLIENT computer.
		static void client_example_download_file() {
			var r = internet.http.Get("http://SERVER:4455/example.html");
			filesystem.saveBytes(@"C:\Test\Somewhere\example.html", r.Bytes());
		}
		
		#endregion
		
		#region internet
		
		//Usually the HTTP server is not directly accessible from the internet. For it you can use ngrok or similar software.
		//For example, on the SERVER computer install/register ngrok, and in cmd execute: ngrok http 4455.
		//Then on CLIENT computer use the URL displayed in the ngrok console window on the SERVER computer.
		
		//Example of code on CLIENT computer.
		static void client_example_internet() {
			internet.http.Get("https://1111-11-111-11-111.ngrok-free.app/", auth: ":password278351");
		}
		
		#endregion
		
		#region more info
		
		//Instead of a C# script on CLIENT computer can be used a web browser or any program or programming language/library that can send HTTP requests. Any device, any OS.
		
		//If you use the URL in a web browser, and SERVER requires a password (calls <b>Auth</b> like in the example), you can either insert <mono>user:password@</mono> after <mono>://</mono> or the web browser will ask for a user name and password.
		
		//If port 4455 unavailable, use some other port. Examples:
		//SERVER: HttpServerSession.Listen<HttpServerSessionExamples>(33333);
		//CLIENT: internet.http.Get("http://SERVER:33333");
		
		//If HTTP requests on LAN work with a delay, possibly because of slow DNS (computer name to IP translation).
		//Workaround: let CLIENT use server IP instead of computer name.
		//Also don't use IPv4 with HttpServerSession.Listen.
		static void client_example_ip() {
			internet.http.Get("http://123.45.67.89:4455");
			
			//Print IP of computer named "SERVER".
			print.it(System.Net.Dns.GetHostAddresses("SERVER"));
		}
		
		#endregion
	}
}