2012-09-19 version 2.5.0:
General
* New notion "import public" that allows a proto file to forward the content
it imports to its importers. For example,
// foo.proto
import public "bar.proto";
import "baz.proto";
// qux.proto
import "foo.proto";
// Stuff defined in bar.proto may be used in this file, but stuff from
// baz.proto may NOT be used without importing it explicitly.
This is useful for moving proto files. To move a proto file, just leave
a single "import public" in the old proto file.
* New enum option "allow_alias" that specifies whether different symbols can
be assigned the same numeric value. Default value is "true". Setting it to
false causes the compiler to reject enum definitions where multiple symbols
have the same numeric value.
C++
* New generated method set_allocated_foo(Type* foo) for message and string
fields. This method allows you to set the field to a pre-allocated object
and the containing message takes the ownership of that object.
* Added SetAllocatedExtension() and ReleaseExtension() to extensions API.
* Custom options are now formatted correctly when descriptors are printed in
text format.
* Various speed optimizations.
Java
* Comments in proto files are now collected and put into generated code as
comments for corresponding classes and data members.
* Added Parser to parse directly into messages without a Builder. For
example,
Foo foo = Foo.getParser().ParseFrom(input);
Using Parser is ~25% faster than using Builder to parse messages.
* Added getters/setters to access the underlying ByteString of a string field
directly.
* ByteString now supports more operations: substring(), prepend(), and
append(). The implementation of ByteString uses a binary tree structure
to support these operations efficiently.
* New method findInitializationErrors() that lists all missing required
fields.
* Various code size and speed optimizations.
Python
* Added support for dynamic message creation. DescriptorDatabase,
DescriptorPool, and MessageFactory work like their C++ couterparts to
simplify Descriptor construction from *DescriptorProtos, and MessageFactory
provides a message instance from a Descriptor.
* Added pickle support for protobuf messages.
* Unknown fields are now preserved after parsing.
* Fixed bug where custom options were not correctly populated. Custom
options can be accessed now.
* Added EnumTypeWrapper that provides better accessibility to enum types.
* Added ParseMessage(descriptor, bytes) to generate a new Message instance
from a descriptor and a byte string.
2011-05-01 version 2.4.1:
C++
* Fixed the frendship problem for old compilers to make the library now gcc 3
compatible again.
* Fixed vcprojects/extract_includes.bat to extract compiler/plugin.h.
Java
* Removed usages of JDK 1.6 only features to make the library now JDK 1.5
compatible again.
* Fixed a bug about negative enum values.
* serialVersionUID is now defined in generated messages for java serializing.
* Fixed protoc to use java.lang.Object, which makes "Object" now a valid
message name again.
Python
* Experimental C++ implementation now requires C++ protobuf library installed.
See the README.txt in the python directory for details.
2011-02-02 version 2.4.0:
General
* The RPC (cc|java|py)_generic_services default value is now false instead of
true.
* Custom options can have aggregate types. For example,
message MyOption {
optional string comment = 1;
optional string author = 2;
}
extend google.protobuf.FieldOptions {
optional MyOption myoption = 12345;
}
This option can now be set as follows:
message SomeType {
optional int32 field = 1 [(myoption) = { comment:'x' author:'y' }];
}
C++
* Various speed and code size optimizations.
* Added a release_foo() method on string and message fields.
* Fixed gzip_output_stream sub-stream handling.
Java
* Builders now maintain sub-builders for sub-messages. Use getFooBuilder() to
get the builder for the sub-message "foo". This allows you to repeatedly
modify deeply-nested sub-messages without rebuilding them.
* Builder.build() no longer invalidates the Builder for generated messages
(You may continue to modify it and then build another message).
* Code generator will generate efficient equals() and hashCode()
implementations if new option java_generate_equals_and_hash is enabled.
(Otherwise, reflection-based implementations are used.)
* Generated messages now implement Serializable.
* Fields with [deprecated=true] will be marked with @Deprecated in Java.
* Added lazy conversion of UTF-8 encoded strings to String objects to improve
performance.
* Various optimizations.
* Enum value can be accessed directly, instead of calling getNumber() on the
enum member.
* For each enum value, an integer constant is also generated with the suffix
_VALUE.
Python
* Added an experimental C++ implementation for Python messages via a Python
extension. Implementation type is controlled by an environment variable
PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION (valid values: "cpp" and "python")
The default value is currently "python" but will be changed to "cpp" in
future release.
* Improved performance on message instantiation significantly.
Most of the work on message instantiation is done just once per message
class, instead of once per message instance.
* Improved performance on text message parsing.
* Allow add() to forward keyword arguments to the concrete class.
E.g. instead of
item = repeated_field.add()
item.foo = bar
item.baz = quux
You can do:
repeated_field.add(foo=bar, baz=quux)
* Added a sort() interface to the BaseContainer.
* Added an extend() method to repeated composite fields.
* Added UTF8 debug string support.
2010-01-08 version 2.3.0:
General
* Parsers for repeated numeric fields now always accept both packed and
unpacked input. The [packed=true] option only affects serializers.
Therefore, it is possible to switch a field to packed format without
breaking backwards-compatibility -- as long as all parties are using
protobuf 2.3.0 or above, at least.
* The generic RPC service code generated by the C++, Java, and Python
generators can be disabled via file options:
option cc_generic_services = false;
option java_generic_services = false;
option py_generic_services = false;
This allows plugins to generate alternative code, possibly specific to some
particular RPC implementation.
protoc
* Now supports a plugin system for code generators. Plugins can generate
code for new languages or inject additional code into the output of other
code generators. Plugins are just binaries which accept a protocol buffer
on stdin and write a protocol buffer to stdout, so they may be written in
any language. See src/google/protobuf/compiler/plugin.proto.
**WARNING**: Plugins are experimental. The interface may change in a
future version.
* If the output location ends in .zip or .jar, protoc will write its output
to a zip/jar archive instead of a directory. For example:
protoc --java_out=myproto_srcs.jar --python_out=myproto.zip myproto.proto
Currently the archive contents are not compressed, though this could change
in the future.
* inf, -inf, and nan can now be used as default values for float and double
fields.
C++
* Various speed and code size optimizations.
* DynamicMessageFactory is now fully thread-safe.
* Message::Utf8DebugString() method is like DebugString() but avoids escaping
UTF-8 bytes.
* Compiled-in message types can now contain dynamic extensions, through use
of CodedInputStream::SetExtensionRegistry().
* Now compiles shared libraries (DLLs) by default on Cygwin and MinGW, to
match other platforms. Use --disable-shared to avoid this.
Java
* parseDelimitedFrom() and mergeDelimitedFrom() now detect EOF and return
false/null instead of throwing an exception.
* Fixed some initialization ordering bugs.
* Fixes for OpenJDK 7.
Python
* 10-25 times faster than 2.2.0, still pure-Python.
* Calling a mutating method on a sub-message always instantiates the message
in its parent even if the mutating method doesn't actually mutate anything
(e.g. parsing from an empty string).
* Expanded descriptors a bit.
2009-08-11 version 2.2.0:
C++
* Lite mode: The "optimize_for = LITE_RUNTIME" option causes the compiler
to generate code which only depends libprotobuf-lite, which is much smaller
than libprotobuf but lacks descriptors, reflection, and some other features.
* Fixed bug where Message.Swap(Message) was only implemented for
optimize_for_speed. Swap now properly implemented in both modes
(Issue 91).
* Added RemoveLast and SwapElements(index1, index2) to Reflection
interface for repeated elements.
* Added Swap(Message) to Reflection interface.
* Floating-point literals in generated code that are intended to be
single-precision now explicitly have 'f' suffix to avoid pedantic warnings
produced by some compilers.
* The [deprecated=true] option now causes the C++ code generator to generate
a GCC-style deprecation annotation (no-op on other compilers).
* google::protobuf::GetEnumDescriptor<SomeGeneratedEnumType>() returns the
EnumDescriptor for that type -- useful for templates which cannot call
SomeGeneratedEnumType_descriptor().
* Various optimizations and obscure bug fixes.
Java
* Lite mode: The "optimize_for = LITE_RUNTIME" option causes the compiler
to generate code which only depends libprotobuf-lite, which is much smaller
than libprotobuf but lacks descriptors, reflection, and some other features.
* Lots of style cleanups.
Python
* Fixed endianness bug with floats and doubles.
* Text format parsing support.
* Fix bug with parsing packed repeated fields in embedded messages.
* Ability to initialize fields by passing keyword args to constructor.
* Support iterators in extend and __setslice__ for containers.
2009-05-13 version 2.1.0:
General
* Repeated fields of primitive types (types other that string, group, and
nested messages) may now use the option [packed = true] to get a more
efficient encoding. In the new encoding, the entire list is written
as a single byte blob using the "length-delimited" wire type. Within
this blob, the individual values are encoded the same way they would
be normally except without a tag before each value (thus, they are
tightly "packed").
* For each field, the generated code contains an integer constant assigned
to the field number. For example, the .proto file:
message Foo { optional int bar_baz = 123; }
would generate the following constants, all with the integer value 123:
C++: Foo::kBarBazFieldNumber
Java: Foo.BAR_BAZ_FIELD_NUMBER
Python: Foo.BAR_BAZ_FIELD_NUMBER
Constants are also generated for extensions, with the same naming scheme.
These constants may be used as switch cases.
* Updated bundled Google Test to version 1.3.0. Google Test is now bundled
in its verbatim form as a nested autoconf package, so you can drop in any
other version of Google Test if needed.
* optimize_for = SPEED is now the default, by popular demand. Use
optimize_for = CODE_SIZE if code size is more important in your app.
* It is now an error to define a default value for a repeated field.
Previously, this was silently ignored (it had no effect on the generated
code).
* Fields can now be marked deprecated like:
optional int32 foo = 1 [deprecated = true];
Currently this does not have any actual effect, but in the future the code
generators may generate deprecation annotations in each language.
* Cross-compiling should now be possible using the --with-protoc option to
configure. See README.txt for more info.
protoc
* --error_format=msvs option causes errors to be printed in Visual Studio
format, which should allow them to be clicked on in the build log to go
directly to the error location.
* The type name resolver will no longer resolve type names to fields. For
example, this now works:
message Foo {}
message Bar {
optional int32 Foo = 1;
optional Foo baz = 2;
}
Previously, the type of "baz" would resolve to "Bar.Foo", and you'd get
an error because Bar.Foo is a field, not a type. Now the type of "baz"
resolves to the message type Foo. This change is unlikely to make a
difference to anyone who follows the Protocol Buffers style guide.
C++
* Several optimizations, including but not limited to:
- Serialization, especially to flat arrays, is 10%-50% faster, possibly
more for small objects.
- Several descriptor operations which previously required locking no longer
do.
- Descriptors are now constructed lazily on first use, rather than at
process startup time. This should save memory in programs which do not
use descriptors or reflection.
- UnknownFieldSet completely redesigned to be more efficient (especially in
terms of memory usage).
- Various optimizations to reduce code size (though the serialization speed
optimizations increased code size).
* Message interface has method ParseFromBoundedZeroCopyStream() which parses
a limited number of bytes from an input stream rather than parsing until
EOF.
* GzipInputStream and GzipOutputStream support reading/writing gzip- or
zlib-compressed streams if zlib is available.
(google/protobuf/io/gzip_stream.h)
* DescriptorPool::FindAllExtensions() and corresponding
DescriptorDatabase::FindAllExtensions() can be used to enumerate all
extensions of a given type.
* For each enum type Foo, protoc will generate functions:
const string& Foo_Name(Foo value);
bool Foo_Parse(const string& name, Foo* result);
The former returns the name of the enum constant corresponding to the given
value while the latter finds the value corresponding to a name.
* RepeatedField and RepeatedPtrField now have back-insertion iterators.
* String fields now have setters that take a char* and a size, in addition
to the existing ones that took char* or const string&.
* DescriptorPool::AllowUnknownDependencies() may be used to tell
DescriptorPool to create placeholder descriptors for unknown entities
referenced in a FileDescriptorProto. This can allow you to parse a .proto
file without having access to other .proto files that it imports, for
example.
* Updated gtest to latest version. The gtest package is now included as a
nested autoconf package, so it should be able to drop new versions into the
"gtest" subdirectory without modification.
Java
* Fixed bug where Message.mergeFrom(Message) failed to merge extensions.
* Message interface has new method toBuilder() which is equivalent to
newBuilderForType().mergeFrom(this).
* All enums now implement the ProtocolMessageEnum interface.
* Setting a field to null now throws NullPointerException.
* Fixed tendency for TextFormat's parsing to overflow the stack when
parsing large string values. The underlying problem is with Java's
regex implementation (which unfortunately uses recursive backtracking
rather than building an NFA). Worked around by making use of possesive
quantifiers.
* Generated service classes now also generate pure interfaces. For a service
Foo, Foo.Interface is a pure interface containing all of the service's
defined methods. Foo.newReflectiveService() can be called to wrap an
instance of this interface in a class that implements the generic
RpcService interface, which provides reflection support that is usually
needed by RPC server implementations.
* RPC interfaces now support blocking operation in addition to non-blocking.
The protocol compiler generates separate blocking and non-blocking stubs
which operate against separate blocking and non-blocking RPC interfaces.
RPC implementations will have to implement the new interfaces in order to
support blocking mode.
* New I/O methods parseDelimitedFrom(), mergeDelimitedFrom(), and
writeDelimitedTo() read and write "delemited" messages from/to a stream,
meaning that the message size precedes the data. This way, you can write
multiple messages to a stream without having to worry about delimiting
them yourself.
* Throw a more descriptive exception when build() is double-called.
* Add a method to query whether CodedInputStream is at the end of the input
stream.
* Add a method to reset a CodedInputStream's size counter; useful when
reading many messages with the same stream.
* equals() and hashCode() now account for unknown fields.
Python
* Added slicing support for repeated scalar fields. Added slice retrieval and
removal of repeated composite fields.
* Updated RPC interfaces to allow for blocking operation. A client may
now pass None for a callback when making an RPC, in which case the
call will block until the response is received, and the response
object will be returned directly to the caller. This interface change
cannot be used in practice until RPC implementations are updated to
implement it.
* Changes to input_stream.py should make protobuf compatible with appengine.
2008-11-25 version 2.0.3:
protoc
* Enum values may now have custom options, using syntax similar to field
options.
* Fixed bug where .proto files which use custom options but don't actually
define them (i.e. they import another .proto file defining the options)
had to explicitly import descriptor.proto.
* Adjacent string literals in .proto files will now be concatenated, like in
C.
* If an input file is a Windows absolute path (e.g. "C:\foo\bar.proto") and
the import path only contains "." (or contains "." but does not contain
the file), protoc incorrectly thought that the file was under ".", because
it thought that the path was relative (since it didn't start with a slash).
This has been fixed.
C++
* Generated message classes now have a Swap() method which efficiently swaps
the contents of two objects.
* All message classes now have a SpaceUsed() method which returns an estimate
of the number of bytes of allocated memory currently owned by the object.
This is particularly useful when you are reusing a single message object
to improve performance but want to make sure it doesn't bloat up too large.
* New method Message::SerializeAsString() returns a string containing the
serialized data. May be more convenient than calling
SerializeToString(string*).
* In debug mode, log error messages when string-type fields are found to
contain bytes that are not valid UTF-8.
* Fixed bug where a message with multiple extension ranges couldn't parse
extensions.
* Fixed bug where MergeFrom(const Message&) didn't do anything if invoked on
a message that contained no fields (but possibly contained extensions).
* Fixed ShortDebugString() to not be O(n^2). Durr.
* Fixed crash in TextFormat parsing if the first token in the input caused a
tokenization error.
* Fixed obscure bugs in zero_copy_stream_impl.cc.
* Added support for HP C++ on Tru64.
* Only build tests on "make check", not "make".
* Fixed alignment issue that caused crashes when using DynamicMessage on
64-bit Sparc machines.
* Simplify template usage to work with MSVC 2003.
* Work around GCC 4.3.x x86_64 compiler bug that caused crashes on startup.
(This affected Fedora 9 in particular.)
* Now works on "Solaris 10 using recent Sun Studio".
Java
* New overload of mergeFrom() which parses a slice of a byte array instead
of the whole thing.
* New method ByteString.asReadOnlyByteBuffer() does what it sounds like.
* Improved performance of isInitialized() when optimizing for code size.
Python
* Corrected ListFields() signature in Message base class to match what
subclasses actually implement.
* Some minor refactoring.
* Don't pass self as first argument to superclass constructor (no longer
allowed in Python 2.6).
2008-09-29 version 2.0.2:
General
* License changed from Apache 2.0 to New BSD.
* It is now possible to define custom "options", which are basically
annotations which may be placed on definitions in a .proto file.
For example, you might define a field option called "foo" like so:
import "google/protobuf/descriptor.proto"
extend google.protobuf.FieldOptions {
optional string foo = 12345;
}
Then you annotate a field using the "foo" option:
message MyMessage {
optional int32 some_field = 1 [(foo) = "bar"]
}
The value of this option is then visible via the message's
Descriptor:
const FieldDescriptor* field =
MyMessage::descriptor()->FindFieldByName("some_field");
assert(field->options().GetExtension(foo) == "bar");
This feature has been implemented and tested in C++ and Java.
Other languages may or may not need to do extra work to support
custom options, depending on how they construct descriptors.
C++
* Fixed some GCC warnings that only occur when using -pedantic.
* Improved static initialization code, making ordering more
predictable among other things.
* TextFormat will no longer accept messages which contain multiple
instances of a singular field. Previously, the latter instance
would overwrite the former.
* Now works on systems that don't have hash_map.
Java
* Print @Override annotation in generated code where appropriate.
Python
* Strings now use the "unicode" type rather than the "str" type.
String fields may still be assigned ASCII "str" values; they will
automatically be converted.
* Adding a property to an object representing a repeated field now
raises an exception. For example:
# No longer works (and never should have).
message.some_repeated_field.foo = 1
Windows
* We now build static libraries rather than DLLs by default on MSVC.
See vsprojects/readme.txt for more information.
2008-08-15 version 2.0.1:
protoc
* New flags --encode and --decode can be used to convert between protobuf text
format and binary format from the command-line.
* New flag --descriptor_set_out can be used to write FileDescriptorProtos for
all parsed files directly into a single output file. This is particularly
useful if you wish to parse .proto files from programs written in languages
other than C++: just run protoc as a background process and have it output
a FileDescriptorList, then parse that natively.
* Improved error message when an enum value's name conflicts with another
symbol defined in the enum type's scope, e.g. if two enum types declared
in the same scope have values with the same name. This is disallowed for
compatibility with C++, but this wasn't clear from the error.
* Fixed absolute output paths on Windows.
* Allow trailing slashes in --proto_path mappings.
C++
* Reflection objects are now per-class rather than per-instance. To make this
possible, the Reflection interface had to be changed such that all methods
take the Message instance as a parameter. This change improves performance
significantly in memory-bandwidth-limited use cases, since it makes the
message objects smaller. Note that source-incompatible interface changes
like this will not be made again after the library leaves beta.
* Heuristically detect sub-messages when printing unknown fields.
* Fix static initialization ordering bug that caused crashes at startup when
compiling on Mac with static linking.
* Fixed TokenizerTest when compiling with -DNDEBUG on Linux.
* Fixed incorrect definition of kint32min.
* Fix bytes type setter to work with byte sequences with embedded NULLs.
* Other irrelevant tweaks.
Java
* Fixed UnknownFieldSet's parsing of varints larger than 32 bits.
* Fixed TextFormat's parsing of "inf" and "nan".
* Fixed TextFormat's parsing of comments.
* Added info to Java POM that will be required when we upload the
package to a Maven repo.
Python
* MergeFrom(message) and CopyFrom(message) are now implemented.
* SerializeToString() raises an exception if the message is missing required
fields.
* Code organization improvements.
* Fixed doc comments for RpcController and RpcChannel, which had somehow been
swapped.
* Fixed text_format_test on Windows where floating-point exponents sometimes
contain extra zeros.
* Fix Python service CallMethod() implementation.
Other
* Improved readmes.
* VIM syntax highlighting improvements.
2008-07-07 version 2.0.0:
* First public release.