C++ SDK for CloudEvents

This SDK is still a work in progress.

The CloudEvent class (generated from protobuf) is based on this open PR to the CloudEvent spec from JemDay.

The PubsubMessage class (generated from protobuf) is based on Google API.

This is not an officially supported Google product.

User Guide

More example use cases are available in header files as comments. The only files that you will directly import and use are in //v1/protocol_binding/.

Setup

Install Bazel Build System

Instuctions found in Bazel documentation.

Import SDK as a Bazel package in WORKSPACE

In //WORKSPACE

# TODO (#63) : Update README to create Bazel target to master repo once merged

git_repository(
    name = "cloudevents_cpp_sdk",
    commit = "20c9855c11bc66efcc6e086571477bb69870be1d",
    remote = "https://github.com/michlee1337/cloudevents-sdk-cpp/tree/binder-all.v2",
)

Set up the build dependencies

Specify any binders needed as a bazel target dependency.

To use PubsubBinder:

cc_binary(
    ...
    deps = [
        ...
        "@cloudevents_cpp_sdk/protocol_binding:pubsub_binder_lib",
    ],
)

To use HttpReqBinder or HttpResBinder:

cc_binary(
    ...
    deps = [
        ...
        "@cloudevents_cpp_sdk/protocol_binding:http_binder_lib",
    ],
)

Binding a CloudEvent to a Protocol-Message in Binary-ContentMode

Import the header file and use XBinder

// import the header for the binder
#include "//v1/protocol_binding/pubsub_binder.h"

using ::google::pubsub::v1::PubsubMessage;
using ::cloudevents::binder::PubsubBinder;
using ::cloudevents_absl::StatusOr;

// create a CloudEvent
CloudEvent my_cloud_event;
my_cloud_event.set_id("my_id");
my_cloud_event.set_source("my_source");
my_cloud_event.set_spec_version("1.0");
my_cloud_event.set_type("my_type");
my_cloud_event.set_binary_data("1010");

// Initialize the binder
PubsubBinder pubsub_binder;

// Create the Message
StatusOr<PubsubMessage> bind = pubsub_binder.Bind(my_cloud_event);

// Check no errors
if (!bind.ok()) {
  std::cerr << bind.status();
}

// unwrap message
PubsubMessage usable_message = *bind;

Binding a CloudEvent to a Protocol-Message in Structured-ContentMode

Import the header file and use Format and XBinder

// import the header for the binder
#include "//v1/protocol_binding/pubsub_binder.h"

using ::google::pubsub::v1::PubsubMessage;
using ::cloudevents::binder::PubsubBinder
using ::cloudevents::format::Format
using ::cloudevents_absl::StatusOr;

// create a CloudEvent
CloudEvent my_cloud_event;
my_cloud_event.set_id("my_id");
my_cloud_event.set_source("my_source");
my_cloud_event.set_spec_version("1.0");
my_cloud_event.set_type("my_type");
my_cloud_event.set_binary_data("1010");

// initialize the binder
PubsubBinder pubsub_binder;

// specify the EventFormat to be used and create the Message
StatusOr<PubsubMessage> bind = pubsub_binder.Bind(my_cloud_event, Format::kJson);

// check no errors
if (!bind.ok()) {
  std::cerr << bind.status();
}

// unwrap message
PubsubMessage usable_message = *bind;

Unbind a CloudEvent from a Protocol-Message

// import the header for the binder of the protocol message you're working with
#include "//v1/protocol_binding/pubsub_binder.h"

using ::google::pubsub::v1::PubsubMessage;
using ::cloudevents::binder::Binder
using ::cloudevents_absl::StatusOr;

PubsubMessage my_pusub_msg = ...; // However you get this message

// initialize the binder
PubsubBinder pubsub_binder;

// create the CloudEvent
StatusOr<CloudEvent> unbind = pubsub_binder.Unbind(my_pusub_msg);

// check no errors
if (!unbind.ok()) {
  std::cerr << unbind.status();
}

// unwrap cloudevent
CloudEvent cloud_event = *unbind;

Samples

Run-able code samples are available in the /samples folder.

Run

1. Create executable
   bazel build //sample:create_event
2. Run executable
   bazel-bin/sample/create_event

File Structure

All logic related to implementing version 1 of the CloudEvent spec can be found in //v1.

• All logic for Protocol Bindings can be found in the subfolder //v1/protocol_binding.
• All logic for Event Formats can be found in the subfolder //v1/event_format.