If you just want to compile ProtoBuf definitions, you can download precompiled binaries of protoc for all platforms right on the ProtoBuf GitHub releases page. They had precompiled binaries at least since 2015, but it’s easy to overlook them in between the many downloads.
Google designed protobuf to be pretty forgiving with versioning: unexpected data is either stored as “extensions” (making it round-trip safe), or silently dropped, depending on the implementation new fields are generally added as “optional”, meaning that old data can be loaded successfully however: do not renumber fields – that would break existing data you should … Read more
For future answer seekers, ProtoBuf now supports Maps natively: message MapMessage { map<string, string> MyMap = 1; }
There’s a few reasons, mostly to do with where these are used – see struct.proto. StringValue can be null, string often can’t be in a language interfacing with protobufs. e.g. in Go strings are always set; the “zero value” for a string is “”, the empty string, so it’s impossible to distinguish between “this value … Read more
I haven’t compared Protocol Buffers with Java’s native serialization in terms of speed, but for interoperability Java’s native serialization is a serious no-no. It’s also not going to be as efficient in terms of space as Protocol Buffers in most cases. Of course, it’s somewhat more flexible in terms of what it can store, and … Read more
Array is mapped via “repeated”: repeated int32 data = 4; Note you might want sint32/uint32. Also note that in all three cases “packed arrays” can be used, which are more efficient; repeated int32 data = 4 [packed=true];
When to use JSON You need or want data to be human readable Data from the service is directly consumed by a web browser Your server side application is written in JavaScript You aren’t prepared to tie the data model to a schema You don’t have the bandwidth to add another tool to your arsenal … Read more
The numbered tags are used to match fields when serializing and deserializing the data. Obviously, if you change the numbering scheme, and apply this change to both serializer and deserializer, there is no issue. Consider though, if you saved data with the first numbering scheme, and loaded it with the second one, it would try … Read more
m2eclipse supports this. First, add the path to your build path: <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>build-helper-maven-plugin</artifactId> <version>1.8</version> <executions> <execution> <id>add-source</id> <phase>generate-sources</phase> <goals> <goal>add-source</goal> </goals> <configuration> <sources> <source>${project.build.directory}/generated-sources/java/</source> </sources> </configuration> </execution> </executions> </plugin> Second, add support for that to m2e: <pluginManagement> <plugins> <plugin> <groupId>org.eclipse.m2e</groupId> <artifactId>lifecycle-mapping</artifactId> <version>1.0.0</version> <configuration> <lifecycleMappingMetadata> <pluginExecutions> <pluginExecution> <pluginExecutionFilter> <groupId>org.codehaus.mojo</groupId> <artifactId>build-helper-maven-plugin</artifactId> <versionRange>[1.0,)</versionRange> <goals> <goal>parse-version</goal> <goal>add-source</goal> <goal>maven-version</goal> … Read more
The Protocol Compiler — protoc — has this functionality built-in via the –decode and –decode_raw flags. This is the same tool you use to generate code from a .proto file so is likely already installed. For example: protoc –decode_raw < message.bin Or using the .proto file: protoc –decode mypkg.MyType myschema.proto < message.bin Here is the … Read more