Manage Topics

A Topic is a label for grouping CourseWork and CourseWorkMaterial stream items within a course. A Topic is typically used to categorize these items by similarity, such as the week the items are assigned or their subject. Users can visually organize and filter stream items in the Classwork view of the Classroom UI.

Each Topic is identified by a unique ID assigned by the server. The Topic resource also contains the following:

  • name: The display name shown in the Classroom UI
  • updateTime: The time the Topic was last updated
  • courseId: The ID of the course that the Topic is associated with

Create a Topic

You can create a new Topic in a course using the topics.create() method, as shown in the following sample:

Java

classroom/snippets/src/main/java/CreateTopic.java
Topic topic = null;
try {
  // Create the new Topic.
  Topic content = new Topic().setName("Semester 1");
  topic = service.courses().topics().create(courseId, content).execute();
  System.out.println("Topic id: " + topic.getTopicId() + "\n" + "Course id: " + courseId);
} catch (GoogleJsonResponseException e) {
  // TODO (developer) - handle error appropriately
  GoogleJsonError error = e.getDetails();
  if (error.getCode() == 404) {
    System.out.printf("The courseId does not exist: %s.\n", courseId);
  } else {
    throw e;
  }
} catch (Exception e) {
  throw e;
}
return topic;

Python

topic = {
    "name": 'Example Topic'
}
response = service.courses().topics().create(
  courseId=<course ID or alias>,
  body=topic).execute()
print('Topic created: ', response['name'])

The name field is always required and must be a non-empty string. All other fields are optional.

Retrieve Topic details

You can retrieve a specific Topic by ID with the topics.get() method, as shown in the following sample:

Java

classroom/snippets/src/main/java/GetTopic.java
Topic topic = null;
try {
  // Get the topic.
  topic = service.courses().topics().get(courseId, topicId).execute();
  System.out.printf("Topic '%s' found.\n", topic.getName());
} catch (GoogleJsonResponseException e) {
  // TODO (developer) - handle error appropriately
  GoogleJsonError error = e.getDetails();
  if (error.getCode() == 404) {
    System.out.printf("The courseId or topicId does not exist: %s, %s.\n", courseId, topicId);
  }
  throw e;
} catch (Exception e) {
  throw e;
}
return topic;

Python

response = service.courses().topics().get(
  courseId=<course ID or alias>,
  id=<topic ID>).execute()
print('{0} ({1})'.format(response['name'], response['topicId']))

Use the topics.list() method to retrieve all Topics in a course, as shown in the following sample:

Java

classroom/snippets/src/main/java/ListTopics.java
List<Topic> topics = new ArrayList<>();
String pageToken = null;

try {
  do {
    ListTopicResponse response =
        service
            .courses()
            .topics()
            .list(courseId)
            .setPageSize(100)
            .setPageToken(pageToken)
            .execute();

    /* Ensure that the response is not null before retrieving data from it to avoid errors. */
    if (response.getTopic() != null) {
      topics.addAll(response.getTopic());
      pageToken = response.getNextPageToken();
    }
  } while (pageToken != null);

  if (topics.isEmpty()) {
    System.out.println("No topics found.");
  } else {
    for (Topic topic : topics) {
      System.out.printf("%s (%s)\n", topic.getName(), topic.getTopicId());
    }
  }
} catch (GoogleJsonResponseException e) {
  // TODO (developer) - handle error appropriately
  GoogleJsonError error = e.getDetails();
  if (error.getCode() == 404) {
    System.out.printf("The courseId does not exist: %s.\n", courseId);
  } else {
    throw e;
  }
} catch (Exception e) {
  throw e;
}
return topics;

Python

topics = []
page_token = None
while True:
    response = service.courses().topics().list(
        pageToken=page_token,
        pageSize=30,
        courseId=<course ID or alias>).execute()
    topics.extend(response.get('topic', []))
    page_token = response.get('nextPageToken', None)
    if not page_token:
        break
if not topics:
    print('No topics found.')
else:
    print('Topics:')
    for topic in topics:
        print('{0} ({1})'.format(topic['name'], topic['topicId']))

Update a Topic

You can update an existing Topic name with the topics.patch() method, as shown in the following sample:

Java

classroom/snippets/src/main/java/UpdateTopic.java
Topic topic = null;
try {
  // Retrieve the topic to update.
  Topic topicToUpdate = service.courses().topics().get(courseId, topicId).execute();

  // Update the name field for the topic retrieved.
  topicToUpdate.setName("Semester 2");

  /* Call the patch endpoint and set the updateMask query parameter to the field that needs to
  be updated. */
  topic =
      service
          .courses()
          .topics()
          .patch(courseId, topicId, topicToUpdate)
          .set("updateMask", "name")
          .execute();

  /* Prints the updated topic. */
  System.out.printf("Topic '%s' updated.\n", topic.getName());
} catch (GoogleJsonResponseException e) {
  // TODO(developer) - handle error appropriately
  GoogleJsonError error = e.getDetails();
  if (error.getCode() == 404) {
    System.out.printf("The courseId or topicId does not exist: %s, %s.\n", courseId, topicId);
  } else {
    throw e;
  }
} catch (Exception e) {
  throw e;
}
return topic;

Python

topic = {
  "name": "New Topic Name"
}
response = service.courses().topics().patch(
  courseId=<course ID or alias>,
  id=<topic ID>,
  updateMask="name",
  body=topic).execute()
print('{0} ({1})'.format(response['name'], response['topicId']))

The Topic id and updateTime fields are server-generated and can't be updated with the API.

Delete a Topic

You can delete an existing Topic with the topics.delete() method, as shown in the following sample:

Java

classroom/snippets/src/main/java/DeleteTopic.java
try {
  service.courses().topics().delete(courseId, topicId).execute();
} catch (GoogleJsonResponseException e) {
  // TODO(developer) - handle error appropriately
  throw e;
} catch (Exception e) {
  throw e;
}