LibWeb: Implement 'fetch controller' struct

2 files changed, 157 insertions, 0 deletions

diff --git a/Userland/Libraries/LibWeb/Fetch/Infrastructure/FetchController.cpp b/Userland/Libraries/LibWeb/Fetch/Infrastructure/FetchController.cpp
new file mode 100644
index 0000000000..451de59ec0
--- /dev/null
+++ b/Userland/Libraries/LibWeb/Fetch/Infrastructure/FetchController.cpp
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Heap/Heap.h>
+#include <LibJS/Runtime/VM.h>
+#include <LibWeb/Fetch/Infrastructure/FetchController.h>
+#include <LibWeb/WebIDL/DOMException.h>
+
+namespace Web::Fetch::Infrastructure {
+
+FetchController::FetchController() = default;
+
+JS::NonnullGCPtr<FetchController> FetchController::create(JS::VM& vm)
+{
+    return { *vm.heap().allocate_without_realm<FetchController>() };
+}
+
+void FetchController::visit_edges(JS::Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_full_timing_info);
+}
+
+// https://fetch.spec.whatwg.org/#finalize-and-report-timing
+void FetchController::report_timing(JS::Object const& global) const
+{
+    // 1. Assert: this’s report timing steps is not null.
+    VERIFY(m_report_timing_steps.has_value());
+
+    // 2. Call this’s report timing steps with global.
+    (*m_report_timing_steps)(global);
+}
+
+// https://fetch.spec.whatwg.org/#fetch-controller-process-the-next-manual-redirect
+void FetchController::process_next_manual_redirect() const
+{
+    // 1. Assert: controller’s next manual redirect steps are not null.
+    VERIFY(m_next_manual_redirect_steps.has_value());
+
+    // 2. Call controller’s next manual redirect steps.
+    (*m_next_manual_redirect_steps)();
+}
+
+// https://fetch.spec.whatwg.org/#extract-full-timing-info
+JS::NonnullGCPtr<FetchTimingInfo> FetchController::extract_full_timing_info() const
+{
+    // 1. Assert: this’s full timing info is not null.
+    VERIFY(m_full_timing_info);
+
+    // 2. Return this’s full timing info.
+    return *m_full_timing_info;
+}
+
+// https://fetch.spec.whatwg.org/#fetch-controller-abort
+void FetchController::abort(JS::VM& vm, Optional<JS::Value> error)
+{
+    auto& realm = *vm.current_realm();
+
+    // 1. Set controller’s state to "aborted".
+    m_state = State::Aborted;
+
+    // 2. Let fallbackError be an "AbortError" DOMException.
+    auto fallback_error = WebIDL::AbortError::create(realm, "Fetch was aborted"sv);
+
+    // 3. Set error to fallbackError if it is not given.
+    if (!error.has_value())
+        error = fallback_error;
+
+    // FIXME: 4. Let serializedError be StructuredSerialize(error). If that threw an exception, catch it, and let serializedError be StructuredSerialize(fallbackError).
+    // FIXME: 5. Set controller’s serialized abort reason to serializedError.
+    (void)error;
+}
+
+// FIXME: https://fetch.spec.whatwg.org/#deserialize-a-serialized-abort-reason
+
+// https://fetch.spec.whatwg.org/#fetch-controller-terminate
+void FetchController::terminate()
+{
+    // To terminate a fetch controller controller, set controller’s state to "terminated".
+    m_state = State::Terminated;
+}
+
+}
diff --git a/Userland/Libraries/LibWeb/Fetch/Infrastructure/FetchController.h b/Userland/Libraries/LibWeb/Fetch/Infrastructure/FetchController.h
new file mode 100644
index 0000000000..6392804c29
--- /dev/null
+++ b/Userland/Libraries/LibWeb/Fetch/Infrastructure/FetchController.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibJS/Forward.h>
+#include <LibJS/Heap/Cell.h>
+#include <LibJS/SafeFunction.h>
+#include <LibWeb/Fetch/Infrastructure/FetchTimingInfo.h>
+
+namespace Web::Fetch::Infrastructure {
+
+// https://fetch.spec.whatwg.org/#fetch-controller
+class FetchController : public JS::Cell {
+    JS_CELL(FetchController, JS::Cell);
+
+public:
+    enum class State {
+        Ongoing,
+        Terminated,
+        Aborted,
+    };
+
+    [[nodiscard]] static JS::NonnullGCPtr<FetchController> create(JS::VM&);
+
+    void set_full_timing_info(JS::NonnullGCPtr<FetchTimingInfo> full_timing_info) { m_full_timing_info = full_timing_info; }
+    void set_report_timing_steps(JS::SafeFunction<void(JS::Object const&)> report_timing_steps) { m_report_timing_steps = move(report_timing_steps); }
+    void set_next_manual_redirect_steps(JS::SafeFunction<void()> next_manual_redirect_steps) { m_next_manual_redirect_steps = move(next_manual_redirect_steps); }
+
+    [[nodiscard]] State state() const { return m_state; }
+
+    void report_timing(JS::Object const&) const;
+    void process_next_manual_redirect() const;
+    [[nodiscard]] JS::NonnullGCPtr<FetchTimingInfo> extract_full_timing_info() const;
+    void abort(JS::VM&, Optional<JS::Value>);
+    void terminate();
+
+private:
+    FetchController();
+
+    virtual void visit_edges(JS::Cell::Visitor&) override;
+
+    // https://fetch.spec.whatwg.org/#fetch-controller-state
+    // state (default "ongoing")
+    //    "ongoing", "terminated", or "aborted"
+    State m_state { State::Ongoing };
+
+    // https://fetch.spec.whatwg.org/#fetch-controller-full-timing-info
+    // full timing info (default null)
+    //    Null or a fetch timing info.
+    JS::GCPtr<FetchTimingInfo> m_full_timing_info;
+
+    // https://fetch.spec.whatwg.org/#fetch-controller-report-timing-steps
+    // report timing steps (default null)
+    //    Null or an algorithm accepting a global object.
+    Optional<JS::SafeFunction<void(JS::Object const&)>> m_report_timing_steps;
+
+    // https://fetch.spec.whatwg.org/#fetch-controller-report-timing-steps
+    // FIXME: serialized abort reason (default null)
+    //     Null or a Record (result of StructuredSerialize).
+
+    // https://fetch.spec.whatwg.org/#fetch-controller-next-manual-redirect-steps
+    // next manual redirect steps (default null)
+    //     Null or an algorithm accepting nothing.
+    Optional<JS::SafeFunction<void()>> m_next_manual_redirect_steps;
+};
+
+}