Auto-detect MimeType based on file extension

misctools/mime.js

@@ -0,0 +1,57 @@
+const json = await (
+  await fetch("https://raw.githubusercontent.com/jshttp/mime-db/master/db.json")
+).json();
+
+json["application/javascript"].extensions.push(
+  `ts`,
+  `tsx`,
+  `mts`,
+  `mtsx`,
+  `cts`,
+  `cjs`,
+  `mjs`,
+  `js`
+);
+
+delete json["application/node"];
+delete json["application/deno"];
+delete json["application/wasm"];
+
+var categories = new Set();
+var all = "pub const all = struct {";
+for (let key of Object.keys(json).sort()) {
+  const [category] = key.split("/");
+  categories.add(category);
+  all += `pub const @"${key}": MimeType = MimeType{.category = .@"${category}", .value = "${key}"};\n`;
+}
+
+const withExtensions = [
+  ...new Set([
+    ...Object.keys(json)
+      .filter((key) => {
+        return !!json[key]?.extensions?.length;
+      })
+      .flatMap((mime) => {
+        return [...new Set([...json[mime].extensions])].map((ext) => {
+          return [`.{.@"${ext}", all.@"${mime}"}`];
+        });
+      })
+      .sort(),
+  ]),
+];
+
+all += "\n";
+
+all += `  pub const extensions = ComptimeStringMap(MimeType, .{
+${withExtensions.join(",\n")},
+});
+};`;
+
+all += "\n";
+
+// all += `pub const Category = enum {
+//     ${[...categories].map((a) => `@"${a}"`).join(", \n")}
+// };
+// `;
+
+console.log(all);

src/javascript/jsc/webcore/response.zig

@@ -1972,7 +1972,23 @@ pub const Blob = struct {
         pub fn initFile(pathlike: JSC.Node.PathOrFileDescriptor, mime_type: ?HTTPClient.MimeType, allocator: std.mem.Allocator) !*Store {
             var store = try allocator.create(Blob.Store);
             store.* = .{
-                .data = .{ .file = FileStore.init(pathlike, mime_type) },
+                .data = .{ .file = FileStore.init(
+                    pathlike,
+                    mime_type orelse brk: {
+                        if (pathlike == .path) {
+                            const sliced = pathlike.path.slice();
+                            if (sliced.len > 0) {
+                                var extname = std.fs.path.extension(sliced);
+                                extname = std.mem.trim(u8, extname, ".");
+                                if (HTTPClient.MimeType.byExtension(extname)) |mime| {
+                                    break :brk mime.value;
+                                }
+                            }
+
+                            break :brk null;
+                        }
+                    },
+                ) },
                 .allocator = allocator,
                 .ref_count = 1,
             };