From 22c226af3f5570514d3d13d82a399577ecd7d280 Mon Sep 17 00:00:00 2001 From: Konstantin Varlamov Date: Tue, 27 Mar 2018 11:50:03 -0400 Subject: C++ migration: make Timestamp class a part of public API (#944) * move Timestamp from model/ to the root directory; * move Timestamp to top-level firebase namespace and update all references; * add conversions to and from native date types; * add a specialization of std::hash; * add comments to public member functions; * rename nanos -> nanoseconds; * add public headers, including Timestamp, to CMake; * increase test coverage. --- .../core/include/firebase/firestore/CMakeLists.txt | 25 +++ .../core/include/firebase/firestore/timestamp.h | 221 +++++++++++++++++++++ 2 files changed, 246 insertions(+) create mode 100644 Firestore/core/include/firebase/firestore/CMakeLists.txt create mode 100644 Firestore/core/include/firebase/firestore/timestamp.h (limited to 'Firestore/core/include') diff --git a/Firestore/core/include/firebase/firestore/CMakeLists.txt b/Firestore/core/include/firebase/firestore/CMakeLists.txt new file mode 100644 index 0000000..e4e7acd --- /dev/null +++ b/Firestore/core/include/firebase/firestore/CMakeLists.txt @@ -0,0 +1,25 @@ +# Copyright 2018 Google +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +# Hack to make the headers show up in IDEs +# (see https://stackoverflow.com/questions/27039019/ and open issue on CMake +# issue tracker: https://gitlab.kitware.com/cmake/cmake/issues/15234) +add_custom_target(firebase_firestore_types_ide SOURCES + document_reference.h + event_listener.h + firestore.h + firestore_errors.h + geo_point.h + timestamp.h +) diff --git a/Firestore/core/include/firebase/firestore/timestamp.h b/Firestore/core/include/firebase/firestore/timestamp.h new file mode 100644 index 0000000..096d121 --- /dev/null +++ b/Firestore/core/include/firebase/firestore/timestamp.h @@ -0,0 +1,221 @@ +/* + * Copyright 2018 Google + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef FIRESTORE_CORE_INCLUDE_FIREBASE_FIRESTORE_TIMESTAMP_H_ +#define FIRESTORE_CORE_INCLUDE_FIREBASE_FIRESTORE_TIMESTAMP_H_ + +#include +#include +#if !defined(_STLPORT_VERSION) +#include // NOLINT(build/c++11) +#endif // !defined(_STLPORT_VERSION) +#include +#include + +namespace firebase { + +/** + * A Timestamp represents a point in time independent of any time zone or + * calendar, represented as seconds and fractions of seconds at nanosecond + * resolution in UTC Epoch time. It is encoded using the Proleptic Gregorian + * Calendar which extends the Gregorian calendar backwards to year one. It is + * encoded assuming all minutes are 60 seconds long, i.e. leap seconds are + * "smeared" so that no leap second table is needed for interpretation. Range is + * from 0001-01-01T00:00:00Z to 9999-12-31T23:59:59.999999999Z. + * + * @see + * https://github.com/google/protobuf/blob/master/src/google/protobuf/timestamp.proto + */ +class Timestamp { + public: + /** + * Creates a new timestamp representing the epoch (with seconds and + * nanoseconds set to 0). + */ + Timestamp(); + + /** + * Creates a new timestamp. + * + * @param seconds The number of seconds of UTC time since Unix epoch + * 1970-01-01T00:00:00Z. Must be from 0001-01-01T00:00:00Z to + * 9999-12-31T23:59:59Z inclusive; otherwise, assertion failure will be + * triggered. + * @param nanoseconds The non-negative fractions of a second at nanosecond + * resolution. Negative second values with fractions must still have + * non-negative nanoseconds values that count forward in time. Must be + * from 0 to 999,999,999 inclusive; otherwise, assertion failure will be + * triggered. + */ + Timestamp(int64_t seconds, int32_t nanoseconds); + + /** + * Creates a new timestamp with the current date. + * + * The precision is up to nanoseconds, depending on the system clock. + * + * @return a new timestamp representing the current date. + */ + static Timestamp Now(); + + /** + * The number of seconds of UTC time since Unix epoch 1970-01-01T00:00:00Z. + */ + int64_t seconds() const { + return seconds_; + } + + /** + * The non-negative fractions of a second at nanosecond resolution. Negative + * second values with fractions still have non-negative nanoseconds values + * that count forward in time. + */ + int32_t nanoseconds() const { + return nanoseconds_; + } + + /** + * Converts `time_t` to a `Timestamp`. + * + * @param seconds_since_unix_epoch + * @parblock + * The number of seconds of UTC time since Unix epoch + * 1970-01-01T00:00:00Z. Can be negative to represent dates before the + * epoch. Must be from 0001-01-01T00:00:00Z to 9999-12-31T23:59:59Z + * inclusive; otherwise, assertion failure will be triggered. + * + * Note that while the epoch of `time_t` is unspecified, it's usually Unix + * epoch. If this assumption is broken, this function will produce + * incorrect results. + * @endparblock + * + * @return a new timestamp with the given number of seconds and zero + * nanoseconds. + */ + static Timestamp FromTimeT(time_t seconds_since_unix_epoch); + +#if !defined(_STLPORT_VERSION) + /** + * Converts `std::chrono::time_point` to a `Timestamp`. + * + * @param time_point + * @parblock + * The time point with system clock's epoch, which is + * presumed to be Unix epoch 1970-01-01T00:00:00Z. Can be negative to + * represent dates before the epoch. Must be from 0001-01-01T00:00:00Z to + * 9999-12-31T23:59:59Z inclusive; otherwise, assertion failure will be + * triggered. + * + * Note that while the epoch of `std::chrono::system_clock` is + * unspecified, it's usually Unix epoch. If this assumption is broken, + * this constructor will produce incorrect results. + * @endparblock + */ + static Timestamp FromTimePoint( + std::chrono::time_point time_point); + + /** + * Converts this `Timestamp` to a `time_point`. + * + * Important: if overflow would occur, the returned value will be the maximum + * or minimum value that `Duration` can hold. Note in particular that `long + * long` is insufficient to hold the full range of `Timestamp` values with + * nanosecond precision (which is why `Duration` defaults to `microseconds`). + */ + template + std::chrono::time_point ToTimePoint() const; +#endif // !defined(_STLPORT_VERSION) + + /** + * Returns a string representation of this `Timestamp` for logging/debugging + * purposes. + * + * Note: the exact string representation is unspecified and subject to change; + * don't rely on the format of the string. + */ + std::string ToString() const; + + private: + // Checks that the number of seconds is within the supported date range, and + // that nanoseconds satisfy 0 <= ns <= 1second. + void ValidateBounds() const; + + int64_t seconds_ = 0; + int32_t nanoseconds_ = 0; +}; + +inline bool operator<(const Timestamp& lhs, const Timestamp& rhs) { + return lhs.seconds() < rhs.seconds() || + (lhs.seconds() == rhs.seconds() && + lhs.nanoseconds() < rhs.nanoseconds()); +} + +inline bool operator>(const Timestamp& lhs, const Timestamp& rhs) { + return rhs < lhs; +} + +inline bool operator>=(const Timestamp& lhs, const Timestamp& rhs) { + return !(lhs < rhs); +} + +inline bool operator<=(const Timestamp& lhs, const Timestamp& rhs) { + return !(lhs > rhs); +} + +inline bool operator!=(const Timestamp& lhs, const Timestamp& rhs) { + return lhs < rhs || lhs > rhs; +} + +inline bool operator==(const Timestamp& lhs, const Timestamp& rhs) { + return !(lhs != rhs); +} + +#if !defined(_STLPORT_VERSION) +template +std::chrono::time_point Timestamp::ToTimePoint() const { + namespace chr = std::chrono; + using TimePoint = chr::time_point; + + // Saturate on overflow + const auto max_value = std::numeric_limits::max(); + if (seconds_ > 0 && max_value / Duration::period::den <= seconds_) { + return TimePoint{Duration(max_value)}; + } + const auto min_value = std::numeric_limits::min(); + if (seconds_ < 0 && min_value / Duration::period::den >= seconds_) { + return TimePoint{Duration(min_value)}; + } + + const auto seconds = chr::duration_cast(chr::seconds(seconds_)); + const auto nanoseconds = + chr::duration_cast(chr::nanoseconds(nanoseconds_)); + return TimePoint{seconds + nanoseconds}; +} +#endif // !defined(_STLPORT_VERSION) + +} // namespace firebase + +namespace std { +template <> +struct hash { + // Note: specialization of `std::hash` is provided for convenience only. The + // implementation is subject to change. + size_t operator()(const firebase::Timestamp& timestamp) const; +}; +} // namespace std + +#endif // FIRESTORE_CORE_INCLUDE_FIREBASE_FIRESTORE_TIMESTAMP_H_ -- cgit v1.2.3