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diff --git a/toolkit/components/glean/bindings/private/Labeled.h b/toolkit/components/glean/bindings/private/Labeled.h
new file mode 100644
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+++ b/toolkit/components/glean/bindings/private/Labeled.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_glean_Labeled_h
+#define mozilla_glean_Labeled_h
+
+#include "nsIGleanMetrics.h"
+#include "nsISupports.h"
+#include "nsWrapperCache.h"
+#include "mozilla/dom/BindingDeclarations.h"
+#include "mozilla/glean/bindings/Boolean.h"
+#include "mozilla/glean/bindings/Counter.h"
+#include "mozilla/glean/bindings/ScalarGIFFTMap.h"
+#include "mozilla/glean/bindings/String.h"
+#include "mozilla/glean/fog_ffi_generated.h"
+
+enum class DynamicLabel : uint16_t;
+
+namespace mozilla::glean {
+
+namespace impl {
+
+template <typename T, typename E>
+class Labeled {
+ public:
+  constexpr explicit Labeled<T, E>(uint32_t id) : mId(id) {}
+
+  /**
+   * Gets a specific metric for a given label.
+   *
+   * If a set of acceptable labels were specified in the `metrics.yaml` file,
+   * and the given label is not in the set, it will be recorded under the
+   * special `OTHER_LABEL` label.
+   *
+   * If a set of acceptable labels was not specified in the `metrics.yaml` file,
+   * only the first 16 unique labels will be used.
+   * After that, any additional labels will be recorded under the special
+   * `OTHER_LABEL` label.
+   *
+   * @param aLabel - a snake_case string under 30 characters in length,
+   *                 otherwise the metric will be recorded under the special
+   *                 `OTHER_LABEL` label and an error will be recorded.
+   */
+  T Get(const nsACString& aLabel) const;
+
+  /**
+   * Gets a specific metric for a given label, using the label's enum variant.
+   *
+   * @param aLabel - a variant of this label's label enum.
+   */
+  T EnumGet(E aLabel) const;
+
+ private:
+  const uint32_t mId;
+};
+
+static inline void UpdateLabeledMirror(Telemetry::ScalarID aMirrorId,
+                                       uint32_t aSubmetricId,
+                                       const nsACString& aLabel) {
+  GetLabeledMirrorLock().apply([&](auto& lock) {
+    auto tuple = std::make_tuple<Telemetry::ScalarID, nsString>(
+        std::move(aMirrorId), NS_ConvertUTF8toUTF16(aLabel));
+    lock.ref()->InsertOrUpdate(aSubmetricId, std::move(tuple));
+  });
+}
+
+template <typename E>
+class Labeled<BooleanMetric, E> {
+ public:
+  constexpr explicit Labeled(uint32_t id) : mId(id) {}
+
+  BooleanMetric Get(const nsACString& aLabel) const {
+    auto submetricId = fog_labeled_boolean_get(mId, &aLabel);
+    // If this labeled metric is mirrored, we need to map the submetric id back
+    // to the label string and mirrored scalar so we can mirror its operations.
+    auto mirrorId = ScalarIdForMetric(mId);
+    if (mirrorId) {
+      UpdateLabeledMirror(mirrorId.extract(), submetricId, aLabel);
+    }
+    return BooleanMetric(submetricId);
+  }
+
+  BooleanMetric EnumGet(E aLabel) const {
+    auto submetricId =
+        fog_labeled_boolean_enum_get(mId, static_cast<uint16_t>(aLabel));
+    auto mirrorId = ScalarIdForMetric(mId);
+    if (mirrorId) {
+      // Telemetry's keyed scalars operate on (16-bit) strings,
+      // so we're going to need the string for this enum.
+      nsCString label;
+      fog_labeled_enum_to_str(mId, static_cast<uint16_t>(aLabel), &label);
+      UpdateLabeledMirror(mirrorId.extract(), submetricId, label);
+    }
+    return BooleanMetric(submetricId);
+  }
+
+ private:
+  const uint32_t mId;
+};
+
+template <typename E>
+class Labeled<CounterMetric, E> {
+ public:
+  constexpr explicit Labeled(uint32_t id) : mId(id) {}
+
+  CounterMetric Get(const nsACString& aLabel) const {
+    auto submetricId = fog_labeled_counter_get(mId, &aLabel);
+    // If this labeled metric is mirrored, we need to map the submetric id back
+    // to the label string and mirrored scalar so we can mirror its operations.
+    auto mirrorId = ScalarIdForMetric(mId);
+    if (mirrorId) {
+      GetLabeledMirrorLock().apply([&](auto& lock) {
+        auto tuple = std::make_tuple<Telemetry::ScalarID, nsString>(
+            mirrorId.extract(), NS_ConvertUTF8toUTF16(aLabel));
+        lock.ref()->InsertOrUpdate(submetricId, std::move(tuple));
+      });
+    }
+    return CounterMetric(submetricId);
+  }
+
+  CounterMetric EnumGet(E aLabel) const {
+    auto submetricId =
+        fog_labeled_counter_enum_get(mId, static_cast<uint16_t>(aLabel));
+    auto mirrorId = ScalarIdForMetric(mId);
+    if (mirrorId) {
+      // Telemetry's keyed scalars operate on (16-bit) strings,
+      // so we're going to need the string for this enum.
+      nsCString label;
+      fog_labeled_enum_to_str(mId, static_cast<uint16_t>(aLabel), &label);
+      UpdateLabeledMirror(mirrorId.extract(), submetricId, label);
+    }
+    return CounterMetric(submetricId);
+  }
+
+ private:
+  const uint32_t mId;
+};
+
+template <typename E>
+class Labeled<StringMetric, E> {
+ public:
+  constexpr explicit Labeled(uint32_t id) : mId(id) {}
+
+  StringMetric Get(const nsACString& aLabel) const {
+    auto submetricId = fog_labeled_string_get(mId, &aLabel);
+    // Why no GIFFT map here?
+    // Labeled Strings can't be mirrored. Telemetry has no compatible probe.
+    return StringMetric(submetricId);
+  }
+
+  StringMetric EnumGet(E aLabel) const {
+    auto submetricId =
+        fog_labeled_string_enum_get(mId, static_cast<uint16_t>(aLabel));
+    // Why no GIFFT map here?
+    // Labeled Strings can't be mirrored. Telemetry has no compatible probe.
+    return StringMetric(submetricId);
+  }
+
+ private:
+  const uint32_t mId;
+};
+
+template <>
+class Labeled<BooleanMetric, DynamicLabel> {
+ public:
+  constexpr explicit Labeled(uint32_t id) : mId(id) {}
+
+  BooleanMetric Get(const nsACString& aLabel) const {
+    auto submetricId = fog_labeled_boolean_get(mId, &aLabel);
+    // If this labeled metric is mirrored, we need to map the submetric id back
+    // to the label string and mirrored scalar so we can mirror its operations.
+    auto mirrorId = ScalarIdForMetric(mId);
+    if (mirrorId) {
+      UpdateLabeledMirror(mirrorId.extract(), submetricId, aLabel);
+    }
+    return BooleanMetric(submetricId);
+  }
+
+  BooleanMetric EnumGet(DynamicLabel aLabel) const = delete;
+
+ private:
+  const uint32_t mId;
+};
+
+template <>
+class Labeled<CounterMetric, DynamicLabel> {
+ public:
+  constexpr explicit Labeled(uint32_t id) : mId(id) {}
+
+  CounterMetric Get(const nsACString& aLabel) const {
+    auto submetricId = fog_labeled_counter_get(mId, &aLabel);
+    // If this labeled metric is mirrored, we need to map the submetric id back
+    // to the label string and mirrored scalar so we can mirror its operations.
+    auto mirrorId = ScalarIdForMetric(mId);
+    if (mirrorId) {
+      GetLabeledMirrorLock().apply([&](auto& lock) {
+        auto tuple = std::make_tuple<Telemetry::ScalarID, nsString>(
+            mirrorId.extract(), NS_ConvertUTF8toUTF16(aLabel));
+        lock.ref()->InsertOrUpdate(submetricId, std::move(tuple));
+      });
+    }
+    return CounterMetric(submetricId);
+  }
+
+  CounterMetric EnumGet(DynamicLabel aLabel) const = delete;
+
+ private:
+  const uint32_t mId;
+};
+
+template <>
+class Labeled<StringMetric, DynamicLabel> {
+ public:
+  constexpr explicit Labeled(uint32_t id) : mId(id) {}
+
+  StringMetric Get(const nsACString& aLabel) const {
+    auto submetricId = fog_labeled_string_get(mId, &aLabel);
+    // Why no GIFFT map here?
+    // Labeled Strings can't be mirrored. Telemetry has no compatible probe.
+    return StringMetric(submetricId);
+  }
+
+  StringMetric EnumGet(DynamicLabel aLabel) const = delete;
+
+ private:
+  const uint32_t mId;
+};
+
+}  // namespace impl
+
+class GleanLabeled final : public nsISupports, public nsWrapperCache {
+ public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(GleanLabeled)
+
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+  nsISupports* GetParentObject() { return nullptr; }
+
+  explicit GleanLabeled(uint32_t aId, uint32_t aTypeId)
+      : mId(aId), mTypeId(aTypeId){};
+
+  already_AddRefed<nsISupports> NamedGetter(const nsAString& aName,
+                                            bool& aFound);
+  bool NameIsEnumerable(const nsAString& aName);
+  void GetSupportedNames(nsTArray<nsString>& aNames);
+
+ private:
+  virtual ~GleanLabeled() = default;
+
+  const uint32_t mId;
+  const uint32_t mTypeId;
+};
+
+}  // namespace mozilla::glean
+
+#endif /* mozilla_glean_Labeled_h */