pbtools 0.12.0

Google Protocol Buffers tools.

About

Google Protocol Buffers tools in Python 3.6+.

• C source code generator.

• Only supports proto3.

Known limitations:

• Recursive messages are not yet supported (probably never will be).

• Options, services (gRPC) and maps are ignored.

• The C type char must be 8 bits.

Project homepage: https://github.com/eerimoq/pbtools

Documentation: http://pbtools.readthedocs.org/en/latest

Installation

pip install pbtools

Example usage

C source code

In this example we use the simple proto-file hello_world.proto.

syntax = "proto3";

package hello_world;

message Foo {
    int32 bar = 1;
}

Generate C source code from the proto-file.

$ pbtools generate_c_source examples/hello_world/hello_world.proto
Successfully generated hello_world.h and hello_world.c.
Successfully created pbtools.h and pbtools.c.

See hello_world.h and hello_world.c for the contents of the generated files.

We’ll use the generated types and functions below.

struct hello_world_foo_t {
   struct pbtools_message_base_t base;
   int32_t bar;
};

struct hello_world_foo_t *hello_world_foo_new(
    void *workspace_p,
    size_t size);

int hello_world_foo_encode(
    struct hello_world_foo_t *self_p,
    void *encoded_p,
    size_t size);

int hello_world_foo_decode(
    struct hello_world_foo_t *self_p,
    const uint8_t *encoded_p,
    size_t size);

Encode and decode the Foo-message in main.c.

#include <stdio.h>
#include "hello_world.h"

int main(int argc, const char *argv[])
{
    int size;
    uint8_t workspace[64];
    uint8_t encoded[16];
    struct hello_world_foo_t *foo_p;

    /* Encode. */
    foo_p = hello_world_foo_new(&workspace[0], sizeof(workspace));

    if (foo_p == NULL) {
        return (1);
    }

    foo_p->bar = 78;
    size = hello_world_foo_encode(foo_p, &encoded[0], sizeof(encoded));

    if (size < 0) {
        return (2);
    }

    printf("Successfully encoded Foo into %d bytes.\n", size);

    /* Decode. */
    foo_p = hello_world_foo_new(&workspace[0], sizeof(workspace));

    if (foo_p == NULL) {
        return (3);
    }

    size = hello_world_foo_decode(foo_p, &encoded[0], size);

    if (size < 0) {
        return (4);
    }

    printf("Successfully decoded %d bytes into Foo.\n", size);
    printf("Foo.bar: %d\n", foo_p->bar);

    return (0);
}

Build and run the program.

$ gcc main.c hello_world.c pbtools.c -o main
$ ./main
Successfully encoded Foo into 2 bytes.
Successfully decoded 2 bytes into Foo.
Foo.bar: 78

See hello_world for all files used in this example.

Command line tool

The generate C source subcommand

Below is an example of how to generate C source code from a proto-file.

$ pbtools generate_c_source examples/address_book/address_book.proto
Successfully generated address_book.h and address_book.c.
Successfully created pbtools.h and pbtools.c.

See address_book.h and address_book.c for the contents of the generated files.