2017-08-14 version 3.4.0 (C++/Java/Python/PHP/Objective-C/C#/Ruby/JavaScript)

Planned Future Changes

* There are some changes that are not included in this release but are planned

for the near future

- Preserve unknown fields in proto3: We are going to bring unknown fields

back into proto3. In this release, some languages start to support

preserving unknown fields in proto3, controlled by flags/options. Some

languages also introduce explicit APIs to drop unknown fields for

migration. Please read the change log sections by languages for details.

For general timeline and plan:

https://docs.google.com/document/d/1KMRX-G91Aa-Y2FkEaHeeviLRRNblgIahbsk4wA14gRk/view

For issues and discussions:

https://github.com/google/protobuf/issues/272

- Make C++ implementation C++11 only: we plan to require C++11 to build

protobuf code starting from 3.5.0 or 3.6.0 release, after unknown fields

semantic changes are finished. Please join this

github issue:

https://github.com/google/protobuf/issues/2780

to provide your feedback.

General

* Extension ranges now accept options and are customizable.

* "reserve" keyword now supports “max” in field number ranges,

e.g. reserve 1000 to max;

C++

* Proto3 messages are now able to preserve unknown fields. The default

behavior is still to drop unknowns, which will be flipped in a future

release. If you rely on unknowns fields being dropped. Please use

Message::DiscardUnknownFields() explicitly.

* Packable proto3 fields are now packed by default in serialization.

* Following C++11 features are introduced when C++11 is available:

- move-constructor and move-assignment are introduced to messages

- Repeated fields constructor now takes std::initializer_list

- rvalue setters are introduced for string fields

* Experimental Table-Driven parsing and serialization available to test. To

enable it, pass in table_driven_parsing table_driven_serialization protoc

generator flags for C++

$ protoc --cpp_out=table_driven_parsing,table_driven_serialization:./ \

test.proto

* lite generator parameter supported by the generator. Once set, all generated

files, use lite runtime regardless of the optimizer_for setting in the

.proto file.

* Various optimizations to make C++ code more performant on PowerPC platform

* Fixed maps data corruption when the maps are modified by both reflection API

and generated API.

* Deterministic serialization on maps reflection now uses stable sort.

* file() accessors are introduced to various *Descriptor classes to make

writing template function easier.

* ByteSize() and SpaceUsed() are deprecated.Use ByteSizeLong() and

SpaceUsedLong() instead

* Consistent hash function is used for maps in DEBUG and NDEBUG build.

* "using namespace std" is removed from stubs/common.h

* Various performance optimizations and bug fixes

Java

* Introduced new parser API DiscardUnknownFieldsParser in preparation of

proto3 unknown fields preservation change. Users who want to drop unknown

fields should migrate to use this new parser API. For example:

Parser<Foo> parser = DiscardUnknownFieldsParser.wrap(Foo.parser());

Foo foo = parser.parseFrom(input);

* Introduced new TextFormat API printUnicodeFieldValue() that prints field

value without escaping unicode characters.

* Added Durations.compare(Duration, Duration) and

Timestamps.compare(Timestamp, Timestamp).

* JsonFormat now accepts base64url encoded bytes fields.

* Optimized CodedInputStream to do less copies when parsing large bytes

fields.

* Optimized TextFormat to allocate less memory when printing.

Python

* SerializeToString API is changed to SerializeToString(self, **kwargs),

deterministic parameter is accepted for deterministic serialization.

* Added sort_keys parameter in json format to make the output deterministic.

* Added indent parameter in json format.

* Added extension support in json format.

* Added __repr__ support for repeated field in cpp implementation.

* Added file in FieldDescriptor.

* Added pretty-print filter to text format.

* Services and method descriptors are always printed even if generic_service

option is turned off.

* Note: AppEngine 2.5 is deprecated on June 2017 that AppEngine 2.5 will

never update protobuf runtime. Users who depend on AppEngine 2.5 should use

old protoc.

PHP

* Support PHP generic services. Specify file option php_generic_service=true

to enable generating service interface.

* Message, repeated and map fields setters take value instead of reference.

* Added map iterator in c extension.

* Support json  encode/decode.

* Added more type info in getter/setter phpdoc

* Fixed the problem that c extension and php implementation cannot be used

together.

* Added file option php_namespace to use custom php namespace instead of

package.

* Added fluent setter.

* Added descriptor API in runtime for custom encode/decode.

* Various bug fixes.

Objective-C

* Fix for GPBExtensionRegistry copying and add tests.

* Optimize GPBDictionary.m codegen to reduce size of overall library by 46K

per architecture.

* Fix some cases of reading of 64bit map values.

* Properly error on a tag with field number zero.

* Preserve unknown fields in proto3 syntax files.

* Document the exceptions on some of the writing apis.

C#

* Implemented IReadOnlyDictionary<K,V> in MapField<K,V>

* Added TryUnpack method for Any message in addition to Unpack.

* Converted C# projects to MSBuild (csproj) format.

Ruby

* Several bug fixes.

Javascript

* Added support of field option js_type. Now one can specify the JS type of a

64-bit integer field to be string in the generated code by adding option

[jstype = JS_STRING] on the field.

2017-04-05 version 3.3.0 (C++/Java/Python/PHP/Objective-C/C#/Ruby/JavaScript)

Planned Future Changes

* There are some changes that are not included in this release but are

planned for the near future:

- Preserve unknown fields in proto3: please read this doc:

https://docs.google.com/document/d/1KMRX-G91Aa-Y2FkEaHeeviLRRNblgIahbsk4wA14gRk/view

for the timeline and follow up this github issue:

https://github.com/google/protobuf/issues/272

for discussion.

- Make C++ implementation C++11 only: we plan to require C++11 to build

protobuf code starting from 3.4.0 or 3.5.0 release. Please join this

github issue:

https://github.com/google/protobuf/issues/2780

to provide your feedback.

C++

* Fixed map fields serialization of DynamicMessage to correctly serialize

both key and value regardless of their presence.

* Parser now rejects field number 0 correctly.

* New API Message::SpaceUsedLong() that’s equivalent to

Message::SpaceUsed() but returns the value in size_t.

* JSON support

- New flag always_print_enums_as_ints in JsonPrintOptions.

- New flag preserve_proto_field_names in JsonPrintOptions. It will instruct

the JSON printer to use the original field name declared in the .proto

file instead of converting them to lowerCamelCase when printing JSON.

- JsonPrintOptions.always_print_primtive_fields now works for oneof message

fields.

- Fixed a bug that doesn’t allow different fields to set the same json_name

value.

- Fixed a performance bug that causes excessive memory copy when printing

large messages.

* Various performance optimizations.

Java

* Map field setters eagerly validate inputs and throw NullPointerExceptions

as appropriate.

* Added ByteBuffer overloads to the generated parsing methods and the Parser

interface.

* proto3 enum's getNumber() method now throws on UNRECOGNIZED values.

* Output of JsonFormat is now locale independent.

Python

* Added FindServiceByName() in the pure-Python DescriptorPool. This works only

for descriptors added with DescriptorPool.Add(). Generated descriptor_pool

does not support this yet.

* Added a descriptor_pool parameter for parsing Any in text_format.Parse().

* descriptor_pool.FindFileContainingSymbol() now is able to find nested

extensions.

* Extending empty [] to repeated field now sets parent message presence.

PHP

* Added file option php_class_prefix. The prefix will be prepended to all

generated classes defined in the file.

* When encoding, negative int32 values are sign-extended to int64.

* Repeated/Map field setter accepts a regular PHP array. Type checking is

done on the array elements.

* encode/decode are renamed to serializeToString/mergeFromString.

* Added mergeFrom, clear method on Message.

* Fixed a bug that oneof accessor didn’t return the field name that is

actually set.

* C extension now works with php7.

* This is the first GA release of PHP. We guarantee that old generated code

can always work with new runtime and new generated code.

Objective-C

* Fixed help for GPBTimestamp for dates before the epoch that contain

fractional seconds.

* Added GPBMessageDropUnknownFieldsRecursively() to remove unknowns from a

message and any sub messages.

* Addressed a threading race in extension registration/lookup.

* Increased the max message parsing depth to 100 to match the other languages.

* Removed some use of dispatch_once in favor of atomic compare/set since it

needs to be heap based.

* Fixes for new Xcode 8.3 warnings.

C#

* Fixed MapField.Values.CopyTo, which would throw an exception unnecessarily

if provided exactly the right size of array to copy to.

* Fixed enum JSON formatting when multiple names mapped to the same numeric

value.

* Added JSON formatting option to format enums as integers.

* Modified RepeatedField<T> to implement IReadOnlyList<T>.

* Introduced the start of custom option handling; it's not as pleasant as it

might be, but the information is at least present. We expect to extend code

generation to improve this in the future.

* Introduced ByteString.FromStream and ByteString.FromStreamAsync to

efficiently create a ByteString from a stream.

* Added whole-message deprecation, which decorates the class with [Obsolete].

Ruby

* Fixed Message#to_h for messages with map fields.

* Fixed memcpy() in binary gems to work for old glibc, without breaking the

build for non-glibc libc’s like musl.

Javascript

* Added compatibility tests for version 3.0.0.

* Added conformance tests.

* Fixed serialization of extensions: we need to emit a value even if it is

falsy (like the number 0).

* Use closurebuilder.py in favor of calcdeps.py for compiling JavaScript.

2017-01-23 version 3.2.0 (C++/Java/Python/PHP/Ruby/Objective-C/C#/JavaScript/Lite)

General

* Added protoc version number to protoc plugin protocol. It can be used by

protoc plugin to detect which version of protoc is used with the plugin and

mitigate known problems in certain version of protoc.

C++

* The default parsing byte size limit has been raised from 64MB to 2GB.

* Added rvalue setters for non-arena string fields.

* Enabled debug logging for Android.

* Fixed a double-free problem when using Reflection::SetAllocatedMessage()

with extension fields.

* Fixed several deterministic serialization bugs:

* MessageLite::SerializeAsString() now respects the global deterministic

serialization flag.

* Extension fields are serialized deterministically as well. Fixed protocol

compiler to correctly report importing-self as an error.

* Fixed FileDescriptor::DebugString() to print custom options correctly.

* Various performance/codesize optimizations and cleanups.

Java

* The default parsing byte size limit has been raised from 64MB to 2GB.

* Added recursion limit when parsing JSON.

* Fixed a bug that enumType.getDescriptor().getOptions() doesn't have custom

options.

* Fixed generated code to support field numbers up to 2^29-1.

Python

* You can now assign NumPy scalars/arrays (np.int32, np.int64) to protobuf

fields, and assigning other numeric types has been optimized for

performance.

* Pure-Python: message types are now garbage-collectable.

* Python/C++: a lot of internal cleanup/refactoring.

PHP (Alpha)

* For 64-bit integers type (int64/uint64/sfixed64/fixed64/sint64), use PHP

integer on 64-bit environment and PHP string on 32-bit environment.

* PHP generated code also conforms to PSR-4 now.

* Fixed ZTS build for c extension.

* Fixed c extension build on Mac.

* Fixed c extension build on 32-bit linux.

* Fixed the bug that message without namespace is not found in the descriptor

pool. (#2240)

* Fixed the bug that repeated field is not iterable in c extension.

* Message names Empty will be converted to GPBEmpty in generated code.

* Added phpdoc in generated files.

* The released API is almost stable. Unless there is large problem, we won't

change it. See

https://developers.google.com/protocol-buffers/docs/reference/php-generated

for more details.

Objective-C

* Added support for push/pop of the stream limit on CodedInputStream for

anyone doing manual parsing.

C#

* No changes.

Ruby

* Message objects now support #respond_to? for field getters/setters.

* You can now compare “message == non_message_object” and it will return false

instead of throwing an exception.

* JRuby: fixed #hashCode to properly reflect the values in the message.

Javascript

* Deserialization of repeated fields no longer has quadratic performance

behavior.

* UTF-8 encoding/decoding now properly supports high codepoints.

* Added convenience methods for some well-known types: Any, Struct, and

Timestamp. These make it easier to convert data between native JavaScript

types and the well-known protobuf types.

2016-09-23 version 3.1.0 (C++/Java/Python/PHP/Ruby/Objective-C/C#/JavaScript/Lite)

General

* Proto3 support in PHP (alpha).

* Various bug fixes.

C++

* Added MessageLite::ByteSizeLong() that’s equivalent to

MessageLite::ByteSize() but returns the value in size_t. Useful to check

whether a message is over the 2G size limit that protobuf can support.

* Moved default_instances to global variables. This allows default_instance

addresses to be known at compile time.

* Adding missing generic gcc 64-bit atomicops.

* Restore New*Callback into google::protobuf namespace since these are used

by the service stubs code

* JSON support.

* Fixed some conformance issues.

* Fixed a JSON serialization bug for bytes fields.

Java

* Fixed a bug in TextFormat that doesn’t accept empty repeated fields (i.e.,

“field: [ ]”).

* JSON support

* Fixed JsonFormat to do correct snake_case-to-camelCase conversion for

non-style-conforming field names.

* Fixed JsonFormat to parse empty Any message correctly.

* Added an option to JsonFormat.Parser to ignore unknown fields.

* Experimental API

* Added UnsafeByteOperations.unsafeWrap(byte[]) to wrap a byte array into

ByteString without copy.

Python

* JSON support

* Fixed some conformance issues.

PHP (Alpha)

* We have added the proto3 support for PHP via both a pure PHP package and a

native c extension. The pure PHP package is intended to provide usability

to wider range of PHP platforms, while the c extension is intended to

provide higher performance. Both implementations provide the same runtime

APIs and share the same generated code. Users don’t need to re-generate

code for the same proto definition when they want to switch the

implementation later. The pure PHP package is included in the php/src

directory, and the c extension is included in the php/ext directory.

Both implementations provide idiomatic PHP APIs:

* All messages and enums are defined as PHP classes.

* All message fields can only be accessed via getter/setter.

* Both repeated field elements and map elements are stored in containers

that act like a normal PHP array.

Unlike several existing third-party PHP implementations for protobuf, our

implementations are built on a "strongly-typed" philosophy: message fields

and array/map containers will throw exceptions eagerly when values of the

incorrect type (not including those that can be type converted, e.g.,

double <-> integer <-> numeric string) are inserted.

Currently, pure PHP runtime supports php5.5, 5.6 and 7 on linux. C

extension runtime supports php5.5 and 5.6 on linux.

See php/README.md for more details about installment. See

https://developers.google.com/protocol-buffers/docs/phptutorial for more

details about APIs.

Objective-C

* Helpers are now provided for working the the Any well known type (see

GPBWellKnownTypes.h for the api additions).

* Some improvements in startup code (especially when extensions aren’t used).

Javascript

* Fixed missing import of jspb.Map

* Fixed valueWriterFn variable name

Ruby

* Fixed hash computation for JRuby's RubyMessage

* Make sure map parsing frames are GC-rooted.

* Added API support for well-known types.

C#

* Removed check on dependency in the C# reflection API.

2016-09-06 version 3.0.2 (C++/Java/Python/Ruby/Objective-C/C#/JavaScript/Lite)

General

* Various bug fixes.

Objective C

* Fix for oneofs in proto3 syntax files where fields were set to the zero

value.

* Fix for embedded null character in strings.

* CocoaDocs support

Ruby

* Fixed memory corruption bug in parsing that could occur under GC pressure.

Javascript

* jspb.Map is now properly exported to CommonJS modules.

C#

* Removed legacy_enum_values flag.

2016-07-27 version 3.0.0 (C++/Java/Python/Ruby/Objective-C/C#/JavaScript/Lite)

General

* This log only contains changes since the beta-4 release. Summarized change

log since the last stable release (v2.6.1) can be found in the github

release page.

Compatibility Notice

* v3.0.0 is the first API stable release of the v3.x series. We do not expect

any future API breaking changes.

* For C++, Java Lite and Objective-C, source level compatibility is

guaranteed. Upgrading from v3.0.0 to newer minor version releases will be

source compatible. For example, if your code compiles against protobuf

v3.0.0, it will continue to compile after you upgrade protobuf library to

v3.1.0.

* For other languages, both source level compatibility and binary level

compatibility are guaranteed. For example, if you have a Java binary built

against protobuf v3.0.0. After switching the protobuf runtime binary to

v3.1.0, your built binary should continue to work.

* Compatibility is only guaranteed for documented API and documented

behaviors. If you are using undocumented API (e.g., use anything in the C++

internal namespace), it can be broken by minor version releases in an

undetermined manner.

Ruby

* When you assign a string field `a.string_field = "X"`, we now call

#encode(UTF-8) on the string and freeze the copy. This saves you from

needing to ensure the string is already encoded as UTF-8. It also prevents

you from mutating the string after it has been assigned (this is how we

ensure it stays valid UTF-8).

* The generated file for `foo.proto` is now `foo_pb.rb` instead of just

`foo.rb`. This makes it easier to see which imports/requires are from

protobuf generated code, and also prevents conflicts with any `foo.rb` file

you might have written directly in Ruby. It is a backward-incompatible

change: you will need to update all of your `require` statements.

* For package names like `foo_bar`, we now translate this to the Ruby module

`FooBar`. This is more idiomatic Ruby than what we used to do (`Foo_bar`).

JavaScript

* Scalar fields like numbers and boolean now return defaults instead of

`undefined` or `null` when they are unset. You can test for presence

explicitly by calling `hasFoo()`, which we now generate for scalar fields.

Java Lite

* Java Lite is now implemented as a separate plugin, maintained in the

`javalite` branch. Both lite runtime and protoc artifacts will be available

in Maven.

C#

* Target platforms now .NET 4.5, selected portable subsets and .NET Core.

* legacy_enum_values option is no longer supported.

2016-07-15 version 3.0.0-beta-4 (C++/Java/Python/Ruby/Objective-C/C#/JavaScript)

General

* Added a deterministic serialization API for C++. The deterministic

serialization guarantees that given a binary, equal messages will be

serialized to the same bytes. This allows applications like MapReduce to

group equal messages based on the serialized bytes. The deterministic

serialization is, however, NOT canonical across languages; it is also

unstable across different builds with schema changes due to unknown fields.

Users who need canonical serialization, e.g. persistent storage in a

canonical form, fingerprinting, etc, should define their own

canonicalization specification and implement the serializer using reflection

APIs rather than relying on this API.

* Added OneofOptions. You can now define custom options for oneof groups.

import "google/protobuf/descriptor.proto";

extend google.protobuf.OneofOptions {

optional int32 my_oneof_extension = 12345;

}

message Foo {

oneof oneof_group {

(my_oneof_extension) = 54321;

...

}

}

C++ (beta)

* Introduced a deterministic serialization API in

CodedOutputStream::SetSerializationDeterministic(bool). See the notes about

deterministic serialization in the General section.

* Added google::protobuf::Map::swap() to swap two map fields.

* Fixed a memory leak when calling Reflection::ReleaseMessage() on a message

allocated on arena.

* Improved error reporting when parsing text format protos.

* JSON

- Added a new parser option to ignore unknown fields when parsing JSON.

- Added convenient methods for message to/from JSON conversion.

* Various performance optimizations.

Java (beta)

* File option "java_generate_equals_and_hash" is now deprecated. equals() and

hashCode() methods are generated by default.

* Added a new JSON printer option "omittingInsignificantWhitespace" to produce

a more compact JSON output. The printer will pretty-print by default.

* Updated Java runtime to be compatible with 2.5.0/2.6.1 generated protos.

Python (beta)

* Added support to pretty print Any messages in text format.

* Added a flag to ignore unknown fields when parsing JSON.

* Bugfix: "@type" field of a JSON Any message is now correctly put before

other fields.

Objective-C (beta)

* Updated the code to support compiling with more compiler warnings

enabled. (Issue 1616)

* Exposing more detailed errors for parsing failures. (PR 1623)

* Small (breaking) change to the naming of some methods on the support classes

for map<>. There were collisions with the system provided KVO support, so

the names were changed to avoid those issues. (PR 1699)

* Fixed for proper Swift bridging of error handling during parsing. (PR 1712)

* Complete support for generating sources that will go into a Framework and

depend on generated sources from other Frameworks. (Issue 1457)

C# (beta)

* RepeatedField optimizations.

* Support for .NET Core.

* Minor bug fixes.

* Ability to format a single value in JsonFormatter (advanced usage only).

* Modifications to attributes applied to generated code.

Javascript (alpha)

* Maps now have a real map API instead of being treated as repeated fields.

* Well-known types are now provided in the google-protobuf package, and the

code generator knows to require() them from that package.

* Bugfix: non-canonical varints are correctly decoded.

Ruby (alpha)

* Accessors for oneof fields now return default values instead of nil.

Java Lite

* Java lite support is removed from protocol compiler. It will be supported

as a protocol compiler plugin in a separate code branch.

2016-05-16 version 3.0.0-beta-3 (C++/Java/Python/Ruby/Nano/Objective-C/C#/JavaScript)

General

* Supported Proto3 lite-runtime in C++/Java for mobile platforms.

* Any type now supports APIs to specify prefixes other than

type.googleapis.com

* Removed javanano_use_deprecated_package option; Nano will always has its own

".nano" package.

C++ (Beta)

* Improved hash maps.

- Improved hash maps comments. In particular, please note that equal hash

maps will not necessarily have the same iteration order and

serialization.

- Added a new hash maps implementation that will become the default in a

later release.

* Arenas

- Several inlined methods in Arena were moved to out-of-line to improve

build performance and code size.

- Added SpaceAllocatedAndUsed() to report both space used and allocated

- Added convenient class UnsafeArenaAllocatedRepeatedPtrFieldBackInserter

* Any

- Allow custom type URL prefixes in Any packing.

- TextFormat now expand the Any type rather than printing bytes.

* Performance optimizations and various bug fixes.

Java (Beta)

* Introduced an ExperimentalApi annotation. Annotated APIs are experimental

and are subject to change in a backward incompatible way in future releases.

* Introduced zero-copy serialization as an ExperimentalApi

- Introduction of the `ByteOutput` interface. This is similar to

`OutputStream` but provides semantics for lazy writing (i.e. no

immediate copy required) of fields that are considered to be immutable.

- `ByteString` now supports writing to a `ByteOutput`, which will directly

expose the internals of the `ByteString` (i.e. `byte[]` or `ByteBuffer`)

to the `ByteOutput` without copying.

- `CodedOutputStream` now supports writing to a `ByteOutput`. `ByteString`

instances that are too large to fit in the internal buffer will be

(lazily) written to the `ByteOutput` directly.

- This allows applications using large `ByteString` fields to avoid

duplication of these fields entirely. Such an application can supply a

`ByteOutput` that chains together the chunks received from

`CodedOutputStream` before forwarding them onto the IO system.

* Other related changes to `CodedOutputStream`

- Additional use of `sun.misc.Unsafe` where possible to perform fast

access to `byte[]` and `ByteBuffer` values and avoiding unnecessary

range checking.

- `ByteBuffer`-backed `CodedOutputStream` now writes directly to the

`ByteBuffer` rather than to an intermediate array.

* Improved lite-runtime.

- Lite protos now implement deep equals/hashCode/toString

- Significantly improved the performance of Builder#mergeFrom() and

Builder#mergeDelimitedFrom()

* Various bug fixes and small feature enhancement.

- Fixed stack overflow when in hashCode() for infinite recursive oneofs.

- Fixed the lazy field parsing in lite to merge rather than overwrite.

- TextFormat now supports reporting line/column numbers on errors.

- Updated to add appropriate @Override for better compiler errors.

Python (Beta)

* Added JSON format for Any, Struct, Value and ListValue

* [ ] is now accepted for both repeated scalar fields and repeated message

fields in text format parser.

* Numerical field name is now supported in text format.

* Added DiscardUnknownFields API for python protobuf message.

Objective-C (Beta)

* Proto comments now come over as HeaderDoc comments in the generated sources

so Xcode can pick them up and display them.

* The library headers have been updated to use HeaderDoc comments so Xcode can

pick them up and display them.

* The per message and per field overhead in both generated code and runtime

object sizes was reduced.

* Generated code now include deprecated annotations when the proto file

included them.

C# (Beta)

In general: some changes are breaking, which require regenerating messages.

Most user-written code will not be impacted *except* for the renaming of enum

values.

* Allow custom type URL prefixes in `Any` packing, and ignore them when

unpacking

* `protoc` is now in a separate NuGet package (Google.Protobuf.Tools)

* New option: `internal_access` to generate internal classes

* Enum values are now PascalCased, and if there's a prefix which matches the

name of the enum, that is removed (so an enum `COLOR` with a value

`COLOR_BLUE` would generate a value of just `Blue`). An option

(`legacy_enum_values`) is temporarily available to disable this, but the

option will be removed for GA.

* `json_name` option is now honored

* If group tags are encountered when parsing, they are validated more

thoroughly (although we don't support actual groups)

* NuGet dependencies are better specified

* Breaking: `Preconditions` is renamed to `ProtoPreconditions`

* Breaking: `GeneratedCodeInfo` is renamed to `GeneratedClrTypeInfo`

* `JsonFormatter` now allows writing to a `TextWriter`

* New interface, `ICustomDiagnosticMessage` to allow more compact

representations from `ToString`

* `CodedInputStream` and `CodedOutputStream` now implement `IDisposable`,

which simply disposes of the streams they were constructed with

* Map fields no longer support null values (in line with other languages)

* Improvements in JSON formatting and parsing

Javascript (Alpha)

* Better support for "bytes" fields: bytes fields can be read as either a

base64 string or UInt8Array (in environments where TypedArray is supported).

* New support for CommonJS imports. This should make it easier to use the

JavaScript support in Node.js and tools like WebPack. See js/README.md for

more information.

* Some significant internal refactoring to simplify and modularize the code.

Ruby (Alpha)

* JSON serialization now properly uses camelCased names, with a runtime option

that will preserve original names from .proto files instead.

* Well-known types are now included in the distribution.

* Release now includes binary gems for Windows, Mac, and Linux instead of just

source gems.

* Bugfix for serializing oneofs.

C++/Java Lite (Alpha)

A new "lite" generator parameter was introduced in the protoc for C++ and

Java for Proto3 syntax messages. Example usage:

./protoc --cpp_out=lite:$OUTPUT_PATH foo.proto

The protoc will treat the current input and all the transitive dependencies

as LITE. The same generator parameter must be used to generate the

dependencies.

In Proto3 syntax files, "optimized_for=LITE_RUNTIME" is no longer supported.

2015-12-30 version 3.0.0-beta-2 (C++/Java/Python/Ruby/Nano/Objective-C/C#/JavaScript)

General

* Introduced a new language implementation: JavaScript.

* Added a new field option "json_name". By default proto field names are

converted to "lowerCamelCase" in proto3 JSON format. This option can be

used to override this behavior and specify a different JSON name for the

field.

* Added conformance tests to ensure implementations are following proto3 JSON

specification.

C++ (Beta)

* Various bug fixes and improvements to the JSON support utility:

- Duplicate map keys in JSON are now rejected (i.e., translation will

fail).

- Fixed wire-format for google.protobuf.Value/ListValue.

- Fixed precision loss when converting google.protobuf.Timestamp.

- Fixed a bug when parsing invalid UTF-8 code points.

- Fixed a memory leak.

- Reduced call stack usage.

Java (Beta)

* Cleaned up some unused methods on CodedOutputStream.

* Presized lists for packed fields during parsing in the lite runtime to

reduce allocations and improve performance.

* Improved the performance of unknown fields in the lite runtime.

* Introduced UnsafeByteStrings to support zero-copy ByteString creation.

* Various bug fixes and improvements to the JSON support utility:

- Fixed a thread-safety bug.

- Added a new option “preservingProtoFieldNames” to JsonFormat.

- Added a new option “includingDefaultValueFields” to JsonFormat.

- Updated the JSON utility to comply with proto3 JSON specification.

Python (Beta)

* Added proto3 JSON format utility. It includes support for all field types

and a few well-known types except for Any and Struct.

* Added runtime support for Any, Timestamp, Duration and FieldMask.

* [ ] is now accepted for repeated scalar fields in text format parser.

* Map fields now have proper O(1) performance for lookup/insert/delete

when using the Python/C++ implementation. They were previously using O(n)

search-based algorithms because the C++ reflection interface didn't

support true map operations.

Objective-C (Beta)

* Various bug-fixes and code tweaks to pass more strict compiler warnings.

* Now has conformance test coverage and is passing all tests.

C# (Beta)

* Various bug-fixes.

* Code generation: Files generated in directories based on namespace.

* Code generation: Include comments from .proto files in XML doc

comments (naively)

* Code generation: Change organization/naming of "reflection class" (access

to file descriptor)

* Code generation and library: Add Parser property to MessageDescriptor,

and introduce a non-generic parser type.

* Library: Added TypeRegistry to support JSON parsing/formatting of Any.

* Library: Added Any.Pack/Unpack support.

* Library: Implemented JSON parsing.

Javascript (Alpha)

* Added proto3 support for JavaScript. The runtime is written in pure

JavaScript and works in browsers and in Node.js. To generate JavaScript

code for your proto, invoke protoc with "--js_out". See js/README.md

for more build instructions.

2015-08-26 version 3.0.0-beta-1 (C++/Java/Python/Ruby/Nano/Objective-C/C#)

About Beta

* This is the first beta release of protobuf v3.0.0. Not all languages

have reached beta stage. Languages not marked as beta are still in

alpha (i.e., be prepared for API breaking changes).

General

* Proto3 JSON is supported in several languages (fully supported in C++

and Java, partially supported in Ruby/C#). The JSON spec is defined in

the proto3 language guide:

https://developers.google.com/protocol-buffers/docs/proto3#json

We will publish a more detailed spec to define the exact behavior of

proto3-conformant JSON serializers and parsers. Until then, do not rely

on specific behaviors of the implementation if it’s not documented in

the above spec. More specifically, the behavior is not yet finalized for

the following:

- Parsing invalid JSON input (e.g., input with trailing commas).

- Non-camelCase names in JSON input.

- The same field appears multiple times in JSON input.

- JSON arrays contain “null” values.

- The message has unknown fields.

* Proto3 now enforces strict UTF-8 checking. Parsing will fail if a string

field contains non UTF-8 data.

C++ (Beta)

* Introduced new utility functions/classes in the google/protobuf/util

directory:

- MessageDifferencer: compare two proto messages and report their

differences.

- JsonUtil: support converting protobuf binary format to/from JSON.

- TimeUtil: utility functions to work with well-known types Timestamp

and Duration.

- FieldMaskUtil: utility functions to work with FieldMask.

* Performance optimization of arena construction and destruction.

* Bug fixes for arena and maps support.

* Changed to use cmake for Windows Visual Studio builds.

* Added Bazel support.

Java (Beta)

* Introduced a new util package that will be distributed as a separate

artifact in maven. It contains:

- JsonFormat: convert proto messages to/from JSON.

- TimeUtil: utility functions to work with Timestamp and Duration.

- FieldMaskUtil: utility functions to work with FieldMask.

* The static PARSER in each generated message is deprecated, and it will

be removed in a future release. A static parser() getter is generated

for each message type instead.

* Performance optimizations for String fields serialization.

* Performance optimizations for Lite runtime on Android:

- Reduced allocations

- Reduced method overhead after ProGuarding

- Reduced code size after ProGuarding

Python (Alpha)

* Removed legacy Python 2.5 support.

* Moved to a single Python 2.x/3.x-compatible codebase, instead of using 2to3.

* Fixed build/tests on Python 2.6, 2.7, 3.3, and 3.4.

- Pure-Python works on all four.

- Python/C++ implementation works on all but 3.4, due to changes in the

Python/C++ API in 3.4.

* Some preliminary work has been done to allow for multiple DescriptorPools

with Python/C++.

Ruby (Alpha)

* Many bugfixes:

- fixed parsing/serialization of bytes, sint, sfixed types

- other parser bugfixes

- fixed memory leak affecting Ruby 2.2

JavaNano (Alpha)

* JavaNano generated code now will be put in a nano package by default to

avoid conflicts with Java generated code.

Objective-C (Alpha)

* Added non-null markup to ObjC library. Requires SDK 8.4+ to build.

* Many bugfixes:

- Removed the class/enum filter.

- Renamed some internal types to avoid conflicts with the well-known types

protos.

- Added missing support for parsing repeated primitive fields in packed or

unpacked forms.

- Added *Count for repeated and map<> fields to avoid auto-create when

checking for them being set.

C# (Alpha)

* Namespace changed to Google.Protobuf (and NuGet package will be named

correspondingly).

* Target platforms now .NET 4.5 and selected portable subsets only.

* Removed lite runtime.

* Reimplementation to use mutable message types.

* Null references used to represent "no value" for message type fields.

* Proto3 semantics supported; proto2 files are prohibited for C# codegen.

Most proto3 features supported:

- JSON formatting (a.k.a. serialization to JSON), including well-known

types (except for Any).

- Wrapper types mapped to nullable value types (or string/ByteString

allowing nullability). JSON parsing is not supported yet.

- maps

- oneof

- enum unknown value preservation

2015-05-25 version 3.0.0-alpha-3 (Objective-C/C#):

General

* Introduced two new language implementations (Objective-C, C#) to proto3.

* Explicit "optional" keyword are disallowed in proto3 syntax, as fields are

optional by default.

* Group fields are no longer supported in proto3 syntax.

* Changed repeated primitive fields to use packed serialization by default in

proto3 (implemented for C++, Java, Python in this release). The user can

still disable packed serialization by setting packed to false for now.

* Added well-known type protos (any.proto, empty.proto, timestamp.proto,

duration.proto, etc.). Users can import and use these protos just like

regular proto files. Additional runtime support will be added for them in

future releases (in the form of utility helper functions, or having them

replaced by language specific types in generated code).

* Added a "reserved" keyword in both proto2 and proto3 syntax. User can use

this keyword to declare reserved field numbers and names to prevent them

from being reused by other fields in the same message.

To reserve field numbers, add a reserved declaration in your message:

message TestMessage {

reserved 2, 15, 9 to 11, 3;

}

This reserves field numbers 2, 3, 9, 10, 11 and 15. If a user uses any of

these as field numbers, the protocol buffer compiler will report an error.

Field names can also be reserved:

message TestMessage {

reserved "foo", "bar";

}

* Various bug fixes since 3.0.0-alpha-2

Objective-C

Objective-C includes a code generator and a native objective-c runtime

library. By adding “--objc_out” to protoc, the code generator will generate

a header(*.pbobjc.h) and an implementation file(*.pbobjc.m) for each proto

file.

In this first release, the generated interface provides: enums, messages,

field support(single, repeated, map, oneof), proto2 and proto3 syntax

support, parsing and serialization. It’s compatible with ARC and non-ARC

usage. Besides, user can also access it via the swift bridging header.

See objectivec/README.md for details.

C#

* C# protobufs are based on project

https://github.com/jskeet/protobuf-csharp-port. The original project was

frozen and all the new development will happen here.

* Codegen plugin for C# was completely rewritten to C++ and is now an

integral part of protoc.

* Some refactorings and cleanup has been applied to the C# runtime library.

* Only proto2 is supported in C# at the moment, proto3 support is in

progress and will likely bring significant breaking changes to the API.

See csharp/README.md for details.

C++

* Added runtime support for Any type. To use Any in your proto file, first

import the definition of Any:

// foo.proto

import "google/protobuf/any.proto";

message Foo {

google.protobuf.Any any_field = 1;

}

message Bar {

int32 value = 1;

}

Then in C++ you can access the Any field using PackFrom()/UnpackTo()

methods:

Foo foo;

Bar bar = ...;

foo.mutable_any_field()->PackFrom(bar);

...

if (foo.any_field().IsType<Bar>()) {

foo.any_field().UnpackTo(&bar);

...

}

* In text format, entries of a map field will be sorted by key.

Java

* Continued optimizations on the lite runtime to improve performance for

Android.

Python

* Added map support.

- maps now have a dict-like interface (msg.map_field[key] = value)

- existing code that modifies maps via the repeated field interface

will need to be updated.

Ruby

* Improvements to RepeatedField's emulation of the Ruby Array API.

* Various speedups and internal cleanups.

2015-02-26 version 3.0.0-alpha-2 (Python/Ruby/JavaNano):

General

* Introduced three new language implementations (Ruby, JavaNano, and

Python) to proto3.

* Various bug fixes since 3.0.0-alpha-1

Python:

Python has received several updates, most notably support for proto3

semantics in any .proto file that declares syntax="proto3".

Messages declared in proto3 files no longer represent field presence

for scalar fields (number, enums, booleans, or strings). You can

no longer call HasField() for such fields, and they are serialized

based on whether they have a non-zero/empty/false value.

One other notable change is in the C++-accelerated implementation.

Descriptor objects (which describe the protobuf schema and allow

reflection over it) are no longer duplicated between the Python

and C++ layers. The Python descriptors are now simple wrappers

around the C++ descriptors. This change should significantly

reduce the memory usage of programs that use a lot of message

types.

Ruby:

We have added proto3 support for Ruby via a native C extension.

The Ruby extension itself is included in the ruby/ directory, and details on

building and installing the extension are in ruby/README.md. The extension

will also be published as a Ruby gem. Code generator support is included as

part of `protoc` with the `--ruby_out` flag.

The Ruby extension implements a user-friendly DSL to define message types

(also generated by the code generator from `.proto` files). Once a message

type is defined, the user may create instances of the message that behave in

ways idiomatic to Ruby. For example:

- Message fields are present as ordinary Ruby properties (getter method

`foo` and setter method `foo=`).

- Repeated field elements are stored in a container that acts like a native

Ruby array, and map elements are stored in a container that acts like a

native Ruby hashmap.

- The usual well-known methods, such as `#to_s`, `#dup`, and the like, are

present.

Unlike several existing third-party Ruby extensions for protobuf, this

extension is built on a "strongly-typed" philosophy: message fields and

array/map containers will throw exceptions eagerly when values of the

incorrect type are inserted.

See ruby/README.md for details.

JavaNano:

JavaNano is a special code generator and runtime library designed especially

for resource-restricted systems, like Android. It is very resource-friendly