Source code
Revision control
Copy as Markdown
Other Tools
/* -*- 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
#ifndef mozilla_glean_GleanEvent_h
#define mozilla_glean_GleanEvent_h
#include "mozilla/dom/BindingDeclarations.h"
#include "mozilla/dom/Record.h"
#include "mozilla/glean/bindings/EventGIFFTMap.h"
#include "mozilla/glean/bindings/GleanMetric.h"
#include "mozilla/glean/fog_ffi_generated.h"
#include "mozilla/ResultVariant.h"
#include "nsString.h"
#include "nsTArray.h"
namespace mozilla::dom {
// forward declaration
struct GleanEventRecord;
} // namespace mozilla::dom
namespace mozilla::glean {
// forward declaration
class GleanEvent;
namespace impl {
/**
* Represents the recorded data for a single event
*/
struct RecordedEvent {
public:
uint64_t mTimestamp;
nsCString mCategory;
nsCString mName;
nsTArray<std::tuple<nsCString, nsCString>> mExtra;
};
template <class T>
class EventMetric {
friend class mozilla::glean::GleanEvent;
public:
constexpr explicit EventMetric(uint32_t id) : mId(id) {}
/**
* Record an event.
*
* @param aExtras The list of (extra key, value) pairs. Allowed extra keys are
* defined in the metric definition.
* If the wrong keys are used or values are too large
* an error is report and no event is recorded.
*/
void Record(const Maybe<T>& aExtras = Nothing()) const {
auto id = EventIdForMetric(mId);
if (id) {
// NB. In case `aExtras` is filled we call `ToFfiExtra`, causing
// twice the required allocation. We could be smarter and reuse the data.
// But this is GIFFT-only allocation, so wait to be told it's a problem.
Maybe<CopyableTArray<Telemetry::EventExtraEntry>> telExtras;
if (aExtras) {
CopyableTArray<Telemetry::EventExtraEntry> extras;
auto serializedExtras = aExtras->ToFfiExtra();
auto keys = std::move(std::get<0>(serializedExtras));
auto values = std::move(std::get<1>(serializedExtras));
for (size_t i = 0; i < keys.Length(); i++) {
extras.EmplaceBack(Telemetry::EventExtraEntry{keys[i], values[i]});
}
telExtras = Some(extras);
}
Telemetry::RecordEvent(id.extract(), Nothing(), telExtras);
}
if (aExtras) {
auto extra = aExtras->ToFfiExtra();
fog_event_record(mId, &std::get<0>(extra), &std::get<1>(extra));
} else {
nsTArray<nsCString> keys;
nsTArray<nsCString> vals;
fog_event_record(mId, &keys, &vals);
}
}
/**
* **Test-only API**
*
* Get a list of currently stored events for this event metric.
*
* This function will attempt to await the last parent-process task (if any)
* writing to the the metric's storage engine before returning a value.
* This function will not wait for data from child processes.
*
* This doesn't clear the stored value.
* Parent process only. Panics in child processes.
*
* @param aPingName The (optional) name of the ping to retrieve the metric
* for. Defaults to the first value in `send_in_pings`.
*
* @return value of the stored metric, or Nothing() if there is no value.
*/
Result<Maybe<nsTArray<RecordedEvent>>, nsCString> TestGetValue(
const nsACString& aPingName = nsCString()) const {
nsCString err;
if (fog_event_test_get_error(mId, &err)) {
return Err(err);
}
if (!fog_event_test_has_value(mId, &aPingName)) {
return Maybe<nsTArray<RecordedEvent>>();
}
nsTArray<FfiRecordedEvent> events;
fog_event_test_get_value(mId, &aPingName, &events);
nsTArray<RecordedEvent> result;
for (const auto& event : events) {
auto ev = result.AppendElement();
ev->mTimestamp = event.timestamp;
ev->mCategory.Append(event.category);
ev->mName.Assign(event.name);
MOZ_ASSERT(event.extras.Length() % 2 == 0);
ev->mExtra.SetCapacity(event.extras.Length() / 2);
for (unsigned int i = 0; i < event.extras.Length(); i += 2) {
// keys & values are interleaved.
nsCString key = std::move(event.extras[i]);
nsCString value = std::move(event.extras[i + 1]);
ev->mExtra.AppendElement(
std::make_tuple(std::move(key), std::move(value)));
}
}
return Some(std::move(result));
}
private:
static const nsCString ExtraStringForKey(uint32_t aKey);
const uint32_t mId;
};
} // namespace impl
struct NoExtraKeys {
std::tuple<nsTArray<nsCString>, nsTArray<nsCString>> ToFfiExtra() const {
nsTArray<nsCString> extraKeys;
nsTArray<nsCString> extraValues;
return std::make_tuple(std::move(extraKeys), std::move(extraValues));
}
};
class GleanEvent final : public GleanMetric {
public:
explicit GleanEvent(uint32_t id, nsISupports* aParent)
: GleanMetric(aParent), mEvent(id) {}
virtual JSObject* WrapObject(
JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override final;
void Record(const dom::Optional<dom::Record<nsCString, nsCString>>& aExtra);
void TestGetValue(const nsACString& aPingName,
dom::Nullable<nsTArray<dom::GleanEventRecord>>& aResult,
ErrorResult& aRv);
private:
virtual ~GleanEvent() = default;
const impl::EventMetric<NoExtraKeys> mEvent;
};
} // namespace mozilla::glean
#endif /* mozilla_glean_GleanEvent.h */