feat: ✨ added basic cli

Cargo.toml

@@ -2,6 +2,7 @@
 members = [
 	"packages/perseus",
 	"packages/perseus-actix-web",
+	"packages/perseus-cli",
 	"examples/showcase/app",
 	"examples/showcase/server-actix-web"
 ]

bonnie.toml

@@ -10,6 +10,11 @@ dev.subcommands.serve.cmd = [
 	"bonnie serve %server"
 ]
 dev.subcommands.serve.args = [ "server" ]
+# TODO fix this with an example
+dev.subcommands.cli = [
+	"cd packages/perseus-cli",
+	"cargo watch -x \"run --bin cli\""
+]
 build = "cargo build"
 test = "cargo watch -x \"test\""
 check = "cargo check && cargo fmt -- --check && cargo clippy && cargo test" # This will be run on CI as well

packages/perseus-cli/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "perseus-cli"
+version = "0.1.0"
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+perseus = { path = "../perseus" }
+perseus-actix-web = { path = "../perseus-actix-web" }
+
+[lib]
+name = "lib"
+
+[[bin]]
+name = "cli"
+path = "src/bin/main.rs"

packages/perseus-cli/src/bin/main.rs

@@ -0,0 +1,60 @@
+use std::env;
+use std::io::Write;
+use lib::{PERSEUS_VERSION, help};
+
+// All this does is run the program and terminate with the acquired exit code
+fn main() {
+    let exit_code = real_main();
+    std::process::exit(exit_code)
+}
+
+// This manages error handling and returns a definite exit code to terminate with
+fn real_main() -> i32 {
+    let res = core();
+    match res {
+        // If it worked, we pass the executed command's exit code through
+        Ok(exit_code) => exit_code,
+        // If something failed, we print the error to `stderr` and return a failure exit code
+        Err(err) => {
+            eprintln!("{}", err);
+            1
+        }
+    }
+}
+
+// This performs the actual logic, separated for deduplication of error handling and destructor control
+// This returns the exit code of the executed command, which we should return from the process itself
+// This prints warnings using the `writeln!` macro, which allows the parsing of `stdout` in production or a vector in testing
+// If at any point a warning can't be printed, the program will panic
+fn core() -> Result<i32, String> {
+    // Get `stdout` so we can write warnings appropriately
+    let stdout = &mut std::io::stdout();
+    // Get the arguments to this program, removing the first one (something like `perseus`)
+    let mut prog_args: Vec<String> = env::args().collect();
+    // This will panic if the first argument is not found (which is probably someone trying to fuzz us)
+    let _executable_name = prog_args.remove(0);
+    // Check for special arguments
+    if matches!(prog_args.get(0), Some(_)) {
+        if prog_args[0] == "-v" || prog_args[0] == "--version" {
+            writeln!(stdout, "You are currently running the Perseus CLI v{}! You can see the latest release at https://github.com/arctic-hen7/perseus/releases.", PERSEUS_VERSION).expect("Failed to write version.");
+            return Ok(0);
+        } else if prog_args[0] == "-h" || prog_args[0] == "--help" {
+            help(stdout);
+            return Ok(0);
+        }
+		// Now we're checking commands
+		else if prog_args[0] == "build" {
+			todo!("build command")
+		} else if prog_args[0] == "serve" {
+			todo!("serve command")
+		} else {
+			writeln!(stdout, "Unknown command '{}'. You can see the help page with -h/--help.", prog_args[0]);
+			return Ok(1);
+		}
+    } else {
+		writeln!(stdout, "Please provide a command to run, or use -h/--help to see the help page.");
+		return Ok(1);
+	}
+
+    Ok(0)
+}

packages/perseus-cli/src/help.rs

@@ -0,0 +1,22 @@
+use crate::PERSEUS_VERSION;
+
+pub fn help(output: &mut impl std::io::Write) {
+    writeln!(
+        output,
+        "Perseus v{version} help page:
+-------------------------
+
+This is the CLI for Perseus, a super-fast WebAssembly frontend development framework! For the full reference, please see the documentation at https://arctic-hen7.github.io/perseus.
+
+-h, --help			prints this help page
+-v, --version			prints the current version of the CLI
+
+build				builds your app (-p/--prod for production, -w/--watch to watch files)
+serve				serves your app (accepts $PORT and $HOST env vars)
+
+Further information can be found at https://arctic-hen7.github.io/perseus.
+        ",
+        version = PERSEUS_VERSION
+    )
+    .expect("Failed to write help page.")
+}

packages/perseus-cli/src/lib.rs

@@ -0,0 +1,4 @@
+mod help;
+
+pub const PERSEUS_VERSION: &str = "0.1.0";
+pub use help::help;