List messages

This guide explains how to use the list() method on the Message resource of the Google Chat API to see a paginated, filterable list of messages in a space.

In the Chat API, a Chat message is represented by the Message resource. While Chat users can only send messages that contain text, Chat apps can use many other messaging features, including displaying static or interactive user interfaces, collecting information from users, and delivering messages privately. To learn more about messaging features available for the Chat API, see the Google Chat messages overview.

Prerequisites

Node.js

Python

Java

Apps Script

List messages as a user

To list messages with user authentication, pass the following in your request:

  • Specify the chat.messages.readonly or chat.messages authorization scope.
  • Call the ListMessages() method.

The following example lists messages in a Chat space:

Node.js

chat/client-libraries/cloud/list-messages-user-cred.js
import {createClientWithUserCredentials} from './authentication-utils.js';

const USER_AUTH_OAUTH_SCOPES = ['https://www.googleapis.com/auth/chat.messages.readonly'];

// This sample shows how to list messages with user credential
async function main() {
  // Create a client
  const chatClient = await createClientWithUserCredentials(USER_AUTH_OAUTH_SCOPES);

  // Initialize request argument(s)
  const request = {
    // Replace SPACE_NAME here
    parent: 'spaces/SPACE_NAME'
  };

  // Make the request
  const pageResult = chatClient.listMessagesAsync(request);

  // Handle the response. Iterating over pageResult will yield results and
  // resolve additional pages automatically.
  for await (const response of pageResult) {
    console.log(response);
  }
}

main().catch(console.error);

Python

chat/client-libraries/cloud/list_messages_user_cred.py
from authentication_utils import create_client_with_user_credentials
from google.apps import chat_v1 as google_chat

SCOPES = ["https://www.googleapis.com/auth/chat.messages.readonly"]

# This sample shows how to list messages with user credential
def list_messages_with_user_cred():
    # Create a client
    client = create_client_with_user_credentials(SCOPES)

    # Initialize request argument(s)
    request = google_chat.ListMessagesRequest(
        # Replace SPACE_NAME here
        parent = 'spaces/SPACE_NAME',
        # Number of results that will be returned at once
        page_size = 100
    )

    # Make the request
    page_result = client.list_messages(request)

    # Handle the response. Iterating over page_result will yield results and
    # resolve additional pages automatically.
    for response in page_result:
        print(response)

list_messages_with_user_cred()

Java

chat/client-libraries/cloud/src/main/java/com/google/workspace/api/chat/samples/ListMessagesUserCred.java
import com.google.chat.v1.ChatServiceClient;
import com.google.chat.v1.ListMessagesRequest;
import com.google.chat.v1.ListMessagesResponse;
import com.google.chat.v1.Message;

// This sample shows how to list messages with user credential.
public class ListMessagesUserCred {

  private static final String SCOPE =
    "https://www.googleapis.com/auth/chat.messages.readonly";

  public static void main(String[] args) throws Exception {
    try (ChatServiceClient chatServiceClient =
        AuthenticationUtils.createClientWithUserCredentials(
          ImmutableList.of(SCOPE))) {
      ListMessagesRequest.Builder request = ListMessagesRequest.newBuilder()
        // Replace SPACE_NAME here.
        .setParent("spaces/SPACE_NAME")
        // Number of results that will be returned at once.
        .setPageSize(10);

      // Iterate over results and resolve additional pages automatically.
      for (Message response :
          chatServiceClient.listMessages(request.build()).iterateAll()) {
        System.out.println(JsonFormat.printer().print(response));
      }
    }
  }
}

Apps Script

chat/advanced-service/Main.gs
/**
 * This sample shows how to list messages with user credential
 * 
 * It relies on the OAuth2 scope 'https://www.googleapis.com/auth/chat.messages.readonly'
 * referenced in the manifest file (appsscript.json).
 */
function listMessagesUserCred() {
  // Initialize request argument(s)
  // TODO(developer): Replace SPACE_NAME here
  const parent = 'spaces/SPACE_NAME';

  // Iterate through the response pages using page tokens
  let responsePage;
  let pageToken = null;
  do {
    // Request response pages
    responsePage = Chat.Spaces.Messages.list(parent, {
      pageSize: 10,
      pageToken: pageToken
    });
    // Handle response pages
    if (responsePage.messages) {
      responsePage.messages.forEach((message) => console.log(message));
    }
    // Update the page token to the next one
    pageToken = responsePage.nextPageToken;
  } while (pageToken);
}

To run this sample, replace SPACE_NAME with the ID from the space's name field. You can obtain the ID by calling the ListSpaces() method or from the space's URL.

The Chat API returns a list of messages sent in the specified space. If there are no messages from the request, the Chat API response returns an empty object. When using a REST/HTTP interface, the response contains an empty JSON object, {}.

List messages as a Chat app

App authentication requires one-time administrator approval.

To list messages from a space with app authentication using the Chat REST API, pass the following in your request:

  • Specify one of the following authorization scopes:
    • https://www.googleapis.com/auth/chat.app.messages.readonly
  • Call the list method on the messages resource.
  • Pass the name of the space to list messages from.

Create an API key

To call a Developer Preview API method, you must use a non-public developer preview version of the API discovery document. To authenticate the request, you must pass an API key.

To create the API Key, open your app's Google Cloud project and do the following:

  1. In the Google Cloud console, go to Menu > APIs & Services > Credentials.

    Go to Credentials

  2. Click Create credentials > API key.
  3. Your new API key is displayed.
    • Click Copy to copy your API key for use in your app's code. The API key can also be found in the "API Keys" section of your project's credentials.
    • To prevent unauthorized use, we recommend restricting where and for which APIs the API key can be used. For more details, see Add API restrictions.

Write a script that calls Chat API

Here's how to list messages with app authentication and the Chat REST API:

Python

  1. In your working directory, create a file named chat_messages_list_app.py.

  2. Include the following code in chat_messages_list_app.py:

    from google.oauth2 import service_account
from apiclient.discovery import build

# Define your app's authorization scopes.
# When modifying these scopes, delete the file token.json, if it exists.
SCOPES = ["https://www.googleapis.com/auth/chat.app.messages.readonly"]

def main():
    '''
    Authenticates with Chat API using app authentication,
    then lists messages from a specified space.
    '''

    # Specify service account details.
    creds = (
        service_account.Credentials.from_service_account_file('credentials.json')
        .with_scopes(SCOPES)
    )

    # Build a service endpoint for Chat API.
    chat = build('chat', 'v1', credentials=creds, discoveryServiceUrl='https://chat.googleapis.com/$discovery/rest?version=v1&labels=DEVELOPER_PREVIEW&key=API_KEY')

    # Use the service endpoint to call Chat API.
    result = chat.spaces().messages().list(

        # The space to list messages from.
        #
        # Replace SPACE_NAME with a space name.
        # Obtain the space name from the spaces resource of Chat API,
        # or from a space's URL.
        parent='spaces/SPACE_NAME'

    ).execute()

    # Print Chat API's response in your command line interface.
    print(result)

if __name__ == '__main__':
    main()

  3. In the code, replace the following:

    • API_KEY: the API key that you created to build the service endpoint for Chat API.

    • SPACE_NAME: a space name, which you can obtain from the spaces.list method in the Chat API, or from a space's URL.

  4. In your working directory, build and run the sample:

    python3 chat_messages_list_app.py

The Chat API returns a list of messages sent in the specified space. If there are no messages from the request, the Chat API response returns an empty object. When using a REST/HTTP interface, the response contains an empty JSON object, {}.