Many Google Cloud services, such as Cloud Billing, send out notifications to share important information with Google Cloud users. By default, these notifications are sent to members with certain Identity and Access Management (IAM) roles. With theEssential Contacts API, you can customize who receives notifications by providing your own list of contacts.
While this library isGA, please note that the Google Cloud C++ client libraries donotfollowSemantic Versioning.
Quickstart
The following shows the code that you'll run in thegoogle/cloud/essentialcontacts/quickstart/directory, which should give you a taste of the Essential Contacts API C++ client library API.
#include "google/cloud/essentialcontacts/v1/essential_contacts_client.h"
#include "google/cloud/project.h"
#include <iostream>
int main(int argc, char* argv[]) try {
if (argc != 2) {
std::cerr << "Usage: " << argv[0] << " project-id\n";
return 1;
}
namespace essentialcontacts = ::google::cloud::essentialcontacts_v1;
auto client = essentialcontacts::EssentialContactsServiceClient(
essentialcontacts::MakeEssentialContactsServiceConnection());
auto const project = google::cloud::Project(argv[1]);
for (auto r : client.ListContacts(project.FullName())) {
if (!r) throw std::move(r).status();
std::cout << r->DebugString() << "\n";
}
return 0;
} catch (google::cloud::Status const& status) {
std::cerr << "google::cloud::Status thrown: " << status << "\n";
return 1;
}
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[[["\u003cp\u003eThe Essential Contacts API C++ Client Library allows customization of who receives notifications from Google Cloud services, such as Cloud Billing, beyond the default IAM role-based distribution.\u003c/p\u003e\n"],["\u003cp\u003eThe latest release candidate version is 2.37.0-rc, and the content contains a list of past versions from 2.36.0 down to 2.12.0.\u003c/p\u003e\n"],["\u003cp\u003eThe library's main class is \u003ccode\u003eessentialcontacts_v1::EssentialContactsServiceClient\u003c/code\u003e, which exposes all Remote Procedure Calls (RPCs) as member functions.\u003c/p\u003e\n"],["\u003cp\u003eThe library does not follow Semantic Versioning, despite being Generally Available (GA).\u003c/p\u003e\n"],["\u003cp\u003eThe documentation provides guides on error handling, endpoint overrides, authentication credentials, retry policies, and environment variable configurations.\u003c/p\u003e\n"]]],[],null,["Version 2.33.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/essentialcontacts/latest)\n- [2.41.0](/cpp/docs/reference/essentialcontacts/2.41.0)\n- [2.40.0](/cpp/docs/reference/essentialcontacts/2.40.0)\n- [2.39.0](/cpp/docs/reference/essentialcontacts/2.39.0)\n- [2.38.0](/cpp/docs/reference/essentialcontacts/2.38.0)\n- [2.37.0](/cpp/docs/reference/essentialcontacts/2.37.0)\n- [2.36.0](/cpp/docs/reference/essentialcontacts/2.36.0)\n- [2.35.0](/cpp/docs/reference/essentialcontacts/2.35.0)\n- [2.34.0](/cpp/docs/reference/essentialcontacts/2.34.0)\n- [2.33.0](/cpp/docs/reference/essentialcontacts/2.33.0)\n- [2.32.0](/cpp/docs/reference/essentialcontacts/2.32.0)\n- [2.31.0](/cpp/docs/reference/essentialcontacts/2.31.0)\n- [2.30.0](/cpp/docs/reference/essentialcontacts/2.30.0)\n- [2.29.0](/cpp/docs/reference/essentialcontacts/2.29.0)\n- [2.28.0](/cpp/docs/reference/essentialcontacts/2.28.0)\n- [2.27.0](/cpp/docs/reference/essentialcontacts/2.27.0)\n- [2.26.0](/cpp/docs/reference/essentialcontacts/2.26.0)\n- [2.25.1](/cpp/docs/reference/essentialcontacts/2.25.1)\n- [2.24.0](/cpp/docs/reference/essentialcontacts/2.24.0)\n- [2.23.0](/cpp/docs/reference/essentialcontacts/2.23.0)\n- [2.22.1](/cpp/docs/reference/essentialcontacts/2.22.1)\n- [2.21.0](/cpp/docs/reference/essentialcontacts/2.21.0)\n- [2.20.0](/cpp/docs/reference/essentialcontacts/2.20.0)\n- [2.19.0](/cpp/docs/reference/essentialcontacts/2.19.0)\n- [2.18.0](/cpp/docs/reference/essentialcontacts/2.18.0)\n- [2.17.0](/cpp/docs/reference/essentialcontacts/2.17.0)\n- [2.16.0](/cpp/docs/reference/essentialcontacts/2.16.0)\n- [2.15.1](/cpp/docs/reference/essentialcontacts/2.15.1)\n- [2.14.0](/cpp/docs/reference/essentialcontacts/2.14.0)\n- [2.13.0](/cpp/docs/reference/essentialcontacts/2.13.0)\n- [2.12.0](/cpp/docs/reference/essentialcontacts/2.12.0) \n\nEssential Contacts API C++ Client Library\n=========================================\n\nMany Google Cloud services, such as Cloud Billing, send out notifications to share important information with Google Cloud users. By default, these notifications are sent to members with certain Identity and Access Management (IAM) roles. With the [Essential Contacts API](https://cloud.google.com/essentialcontacts), you can customize who receives notifications by providing your own list of contacts.\n\nWhile this library is **GA** , please note that the Google Cloud C++ client libraries do **not** follow [Semantic Versioning](https://semver.org/).\n\n### Quickstart\n\nThe following shows the code that you'll run in the `google/cloud/essentialcontacts/quickstart/` directory, which should give you a taste of the Essential Contacts API C++ client library API. \n\n #include \"google/cloud/essentialcontacts/v1/essential_contacts_client.h\"\n #include \"google/cloud/project.h\"\n #include \u003ciostream\u003e\n\n int main(int argc, char* argv[]) try {\n if (argc != 2) {\n std::cerr \u003c\u003c \"Usage: \" \u003c\u003c argv[0] \u003c\u003c \" project-id\\n\";\n return 1;\n }\n\n namespace essentialcontacts = ::google::cloud::essentialcontacts_v1;\n auto client = essentialcontacts::EssentialContactsServiceClient(\n essentialcontacts::MakeEssentialContactsServiceConnection());\n\n auto const project = google::cloud::Project(argv[1]);\n for (auto r : client.ListContacts(project.FullName())) {\n if (!r) throw std::move(r).status();\n std::cout \u003c\u003c r-\u003eDebugString() \u003c\u003c \"\\n\";\n }\n\n return 0;\n } catch (google::cloud::Status const& status) {\n std::cerr \u003c\u003c \"google::cloud::Status thrown: \" \u003c\u003c status \u003c\u003c \"\\n\";\n return 1;\n }\n\n### Main classes\n\nThe main class in this library is [`essentialcontacts_v1::EssentialContactsServiceClient`](/cpp/docs/reference/essentialcontacts/2.33.0/classgoogle_1_1cloud_1_1essentialcontacts__v1_1_1EssentialContactsServiceClient). All RPCs are exposed as member functions of this class. Other classes provide helpers, configuration parameters, and infrastructure to mock [`essentialcontacts_v1::EssentialContactsServiceClient`](/cpp/docs/reference/essentialcontacts/2.33.0/classgoogle_1_1cloud_1_1essentialcontacts__v1_1_1EssentialContactsServiceClient) when testing your application.\n\n### More Information\n\n- [Error Handling](https://cloud.google.com/cpp/docs/reference/common/latest/common-error-handling.html) - describes how the library reports errors.\n- [How to Override the Default Endpoint](/cpp/docs/reference/essentialcontacts/2.33.0/essentialcontacts-override-endpoint) - describes how to override the default endpoint.\n- [How to Override the Authentication Credentials](/cpp/docs/reference/essentialcontacts/2.33.0/essentialcontacts-override-authentication) - describes how to change the authentication credentials used by the library.\n- [Override Retry, Backoff, and Idempotency Policies](/cpp/docs/reference/essentialcontacts/2.33.0/essentialcontacts-override-retry) - describes how to change the default retry policies.\n- [Environment Variables](/cpp/docs/reference/essentialcontacts/2.33.0/essentialcontacts-env) - describes environment variables that can configure the behavior of the library."]]