get fetch campire working

src/browser/webapi/net/Fetch.zig

@@ -1,5 +1,8 @@
 const std = @import("std");
 
+const log = @import("../../../log.zig");
+const Http = @import("../../../http/Http.zig");
+
 const js = @import("../../js/js.zig");
 const Page = @import("../../Page.zig");
 
@@ -8,15 +11,64 @@ const Response = @import("Response.zig");
 
 const Allocator = std.mem.Allocator;
 
-_arena: Allocator,
-_promise: js.Promise,
-_has_response: bool,
+const Fetch = @This();
+
+_page: *Page,
+_response: std.ArrayList(u8),
+_resolver: js.PersistentPromiseResolver,
 
 pub const Input = Request.Input;
 
+// @ZIGDOM just enough to get campire demo working
 pub fn init(input: Input, page: *Page) !js.Promise {
-    // @ZIGDOM
-    _ = input;
-    _ = page;
-    return undefined;
+    const request = try Request.init(input, page);
+
+    const fetch = try page.arena.create(Fetch);
+    fetch.* = .{
+        ._page = page,
+        ._response = .empty,
+        ._resolver = try page.js.createPromiseResolver(.page),
+    };
+
+    const http_client = page._session.browser.http_client;
+    const headers = try http_client.newHeaders();
+
+    try http_client.request(.{
+        .ctx = fetch,
+        .url = request._url,
+        .method = .GET,
+        .headers = headers,
+        .cookie_jar = &page._session.cookie_jar,
+        .resource_type = .fetch,
+        .header_callback = httpHeaderDoneCallback,
+        .data_callback = httpDataCallback,
+        .done_callback = httpDoneCallback,
+        .error_callback = httpErrorCallback,
+    });
+    return fetch._resolver.promise();
+}
+
+fn httpHeaderDoneCallback(transfer: *Http.Transfer) !void {
+    const self: *Fetch = @ptrCast(@alignCast(transfer.ctx));
+    _ = self;
+}
+
+fn httpDataCallback(transfer: *Http.Transfer, data: []const u8) !void {
+    const self: *Fetch = @ptrCast(@alignCast(transfer.ctx));
+    try self._response.appendSlice(self._page.arena, data);
+}
+
+fn httpDoneCallback(ctx: *anyopaque) !void {
+    const self: *Fetch = @ptrCast(@alignCast(ctx));
+
+    const page = self._page;
+    const res = try Response.initFromFetch(page.arena, self._response.items, page);
+    return self._resolver.resolve(res);
+}
+
+fn httpErrorCallback(ctx: *anyopaque, err: anyerror) void {
+    const self: *Fetch = @ptrCast(@alignCast(ctx));
+    self._resolver.reject(@errorName(err)) catch |inner| {
+        log.err(.bug, "failed to reject", .{ .source = "fetch", .err = inner, .reject = err });
+    };
 }