[dingus] Trying to get a web dingus working with pyodide

dingus/worker.js

@@ -0,0 +1,89 @@
+const PARSER_PACKAGE = "./wheel/lrparsers-0.7.9-py3-none-any.whl"
+
+
+// Load the whole pyodide thingy.
+importScripts("pyodide/pyodide.js");
+
+const dingus_module = {
+  post_grammar_status: function (message) {
+    console.log("Grammar Status:", message);
+    postMessage({kind: "grammar_status", status: "loading", message});
+  },
+
+  post_grammar_loaded: function () {
+    console.log("Grammar Loaded");
+    postMessage({kind: "grammar_status", status: "ok", message: "Grammar loaded"});
+  },
+
+  post_grammar_error: function(error) {
+    console.log("Grammar Error:", error);
+    postMessage({kind:"grammar_status", status: "error", message: error});
+  },
+};
+
+async function setup_python() {
+  console.log("Loading pyodide....");
+  const pyodide = await loadPyodide({
+    packages: ["micropip"],
+  });
+  pyodide.setStdout({ batched: (msg) => console.log(msg) }); // TODO: I know this is an option above.
+
+  // TODO: Do I actually want micropip? Probably not?
+  console.log("Installing parser package...");
+  const micropip = pyodide.pyimport("micropip");
+  await micropip.install(PARSER_PACKAGE);
+
+  pyodide.registerJsModule("dingus", dingus_module);
+
+  pyodide.runPython(`
+import dingus
+import parser
+import pyodide.code
+
+GRAMMAR_GLOBALS = {}
+
+def eval_grammar(code):
+  global GRAMMAR_GLOBALS
+  try:
+    dingus.post_grammar_status("Evaluating grammar...")
+    pyodide.code.eval_code(code, globals=GRAMMAR_GLOBALS)
+    dingus.post_grammar_loaded()
+  except Exception as e:
+    dingus.post_grammar_error(f"{e}")
+`);
+
+  console.log("Loaded!");
+  self.pyodide = pyodide;
+  return pyodide;
+}
+const pyodide_promise = setup_python();
+
+
+async function load_grammar_module(code) {
+  const pyodide = self.pyodide;
+
+  console.log("Running...");
+
+  const my_fn = pyodide.globals.get("eval_grammar");
+  my_fn(code);
+  my_fn.destroy();
+}
+
+self.onmessage = async function(event) {
+  await pyodide_promise;
+
+  try {
+    const { kind, data } = event.data;
+    if (kind === "grammar_module") {
+      try {
+        await load_grammar_module(data);
+      } catch (e) {
+        console.log("INTERNAL ERROR:", e.message);
+        postMessage({error: e.message});
+      }
+    }
+  } catch (wtf) {
+    console.log("WTF?");
+    console.log(wtf);
+  }
+};