Kursaliasse verwalten

Mit einer Kursalias-Ressource können Sie unter einem anderen Namen auf Kurse verweisen. Kurs-Aliasse bilden eine Zuordnung zwischen Google Classroom-Kurs-IDs und externen Kurs-IDs.

Wir empfehlen, immer die Kurs-ID des SIS als Kursalias zu verwenden, wenn Sie einen Kurs aus einem SIS erstellen oder einen Kurs mit einem SIS verknüpfen. Mit der Classroom API können Sie dies direkt bei der Kurserstellung tun, indem Sie den Parameter id des Kurses als Alias angeben. Wenn der Alias bereits vorhanden ist, schlägt die Kurserstellung mit dem Fehler ALREADY_EXISTS (409) fehl. Dadurch wird verhindert, dass Kurse doppelt erstellt werden, wenn ein Fehler im Synchronisierungsprogramm vorliegt.

Es gibt zwei Arten von Aliassen: domainweit und projektweit.

  • Domainweite Aliasse haben das Präfix d: und sind für alle Nutzer der Classroom API sichtbar.
  • Projektweite Aliasse verwenden das Präfix p: und können nur von der Anwendung (Entwicklerkonsolenprojekt) gesehen und verwendet werden, mit der sie erstellt wurden.

Aliasse können überall in der API verwendet werden, wo eine Kurs-ID erwartet wird. Sobald ein Alias über die API registriert ist, kann er zum Lesen und Ändern von Kurs- und Teilnehmerlisteninformationen verwendet werden.

Aus Sicht der SIS-Synchronisierung bedeutet dies, dass die interne SIS-ID für einen Kurs als domainweiter Alias für den Kurs registriert werden kann. So kann jeder Entwickler, der sowohl das SIS als auch Classroom integriert hat, einfach die SIS-ID verwenden, um mit Classroom-Daten zu interagieren.

Wenn wir beispielsweise davon ausgehen, dass der SIS-Name school und die vom SIS für einen bestimmten Kurs verwendete interne Kennung math_101 ist, können Sie einen Alias als d:school_math_101 erstellen.

Alias für einen neuen Kurs hinzufügen

Wenn Sie einen Alias für einen neuen Kurs hinzufügen möchten, legen Sie für course.id bei der courses.create()-Anfrage den gewünschten Alias fest.

Apps Script

classroom/snippets/createAlias.gs
/**
 * Creates Course with an alias specified
 */
function createAlias() {
  let course = {
    id: 'p:bio_101',
    name: '10th Grade Biology',
    section: 'Period 2',
    descriptionHeading: 'Welcome to 10th Grade Biology',
    description: 'We\'ll be learning about the structure of living creatures from a combination ' +
      'of textbooks, guest lectures, and lab work. Expect to be excited!',
    room: '301',
    ownerId: 'me',
    courseState: 'PROVISIONED'
  };
  try {
    // Create the course using course details.
    course = Classroom.Courses.create(course);
    console.log('Course created: %s (%s)', course.name, course.id);
  } catch (err) {
    // TODO (developer) - Handle Courses.create() exception
    console.log('Failed to create course %s with an error %s', course.name, err.message);
  }
}

Java

classroom/snippets/src/main/java/CreateCourseWithAlias.java
Course course = null;

/* Create a new Course with the alias set as the id field. Project-wide aliases use a prefix
of "p:" and can only be seen and used by the application that created them. */
Course content =
    new Course()
        .setId("p:history_4_2022")
        .setName("9th Grade History")
        .setSection("Period 4")
        .setDescriptionHeading("Welcome to 9th Grade History.")
        .setOwnerId("me")
        .setCourseState("PROVISIONED");

try {
  course = service.courses().create(content).execute();
  // Prints the new created course id and name
  System.out.printf("Course created: %s (%s)\n", course.getName(), course.getId());
} catch (GoogleJsonResponseException e) {
  // TODO (developer) - handle error appropriately
  GoogleJsonError error = e.getDetails();
  if (error.getCode() == 409) {
    System.out.printf("The course alias already exists: %s.\n", content.getId());
  } else {
    throw e;
  }
} catch (Exception e) {
  throw e;
}
return course;

Python

classroom/snippets/classroom_add_alias_new.py
SCOPES = ["https://www.googleapis.com/auth/classroom.courses"]


def classroom_add_alias_new():
  """
  Creates a course with alias specification the user has access to.
  The file token.json stores the user's access and refresh tokens, and is
  created automatically when the authorization flow completes for
  the first time.
  Load pre-authorized user credentials from the environment.
  TODO(developer) - See https://developers.google.com/identity for
   guides on implementing OAuth2 for the application.
  """
  # pylint: disable=maybe-no-member
  creds = None
  if os.path.exists("token.json"):
    creds = Credentials.from_authorized_user_file("token.json", SCOPES)
  # If there are no (valid) credentials available, let the user log in.
  if not creds or not creds.valid:
    if creds and creds.expired and creds.refresh_token:
      creds.refresh(Request())
    else:
      flow = InstalledAppFlow.from_client_secrets_file(
          "credentials.json", SCOPES
      )
      creds = flow.run_local_server(port=0)
    # Save the credentials for the next run
    with open("token.json", "w", encoding="utf8") as token:
      token.write(creds.to_json())

  alias = "d:school_physics_333"
  course = {
      "id": alias,
      "name": "English",
      "section": "Period 2",
      "description": "Course Description",
      "room": "301",
      "ownerId": "me",
  }
  try:
    print("-------------")
    service = build("classroom", "v1", credentials=creds)
    course = service.courses().create(body=course).execute()
    print("====================================")

  except HttpError as error:
    print(f"An error occurred: {error}")
  return course


if __name__ == "__main__":
  # pylint: disable=too-many-arguments
  # Put the course_id of course whose alias needs to be created.
  classroom_add_alias_new()

Alias für einen vorhandenen Kurs hinzufügen

Wenn Sie den Alias einem vorhandenen Kurs hinzufügen möchten, können Sie für alias den gewünschten Alias festlegen und die Methode courses.aliases.create() verwenden.

Apps Script

classroom/snippets/addAlias.gs
/**
 * Updates the section and room of Google Classroom.
 * @param {string} course_id
 * @see https://developers.google.com/classroom/reference/rest/v1/courses.aliases/create
 */
function addAlias(course_id) {
  const alias = {
    'alias': 'p:bio_101'
  };
  try {
    const course_alias = Classroom.Courses.Aliases.create(resource=alias, courseId=course_id);
    console.log('%s successfully added as an alias!', course_alias.alias);
  } catch (err) {
    // TODO (developer) - Handle exception
    console.log('Request to add alias %s failed with error %s.', alias.alias, err.message);
  }
}

Java

classroom/snippets/src/main/java/AddAliasToCourse.java
/* Create a new CourseAlias object with a project-wide alias. Project-wide aliases use a prefix
of "p:" and can only be seen and used by the application that created them. */
CourseAlias content = new CourseAlias().setAlias("p:biology_10");
CourseAlias courseAlias = null;

try {
  courseAlias = service.courses().aliases().create(courseId, content).execute();
  System.out.printf("Course alias created: %s \n", courseAlias.getAlias());
} catch (GoogleJsonResponseException e) {
  // TODO (developer) - handle error appropriately
  GoogleJsonError error = e.getDetails();
  if (error.getCode() == 409) {
    System.out.printf("The course alias already exists: %s.\n", content);
  } else {
    throw e;
  }
} catch (Exception e) {
  throw e;
}
return courseAlias;

Python

classroom/snippets/classroom_add_alias_existing.py
def classroom_add_alias_existing(course_id):
  """
  Adds alias to existing course with specific course_id.
  Load pre-authorized user credentials from the environment.
  TODO(developer) - See https://developers.google.com/identity
  for guides on implementing OAuth2 for the application.
  """
  creds, _ = google.auth.default()
  # pylint: disable=maybe-no-member
  service = build("classroom", "v1", credentials=creds)
  alias = "d:school_math_101"
  course_alias = {"alias": alias}
  try:
    course_alias = (
        service.courses()
        .aliases()
        .create(courseId=course_id, body=course_alias)
        .execute()
    )
    return course_alias
  except HttpError as error:
    print(f"An error occurred: {error}")
    print("Alias Creation Failed")
  return course_alias


if __name__ == "__main__":
  # Put the course_id of course whose alias needs to be added.
  classroom_add_alias_existing(456058313539)

Kursaliasse abrufen

Mit der Methode courses.aliases.list() können Sie die Aliasse für einen Kurs abrufen, wie im folgenden Beispiel gezeigt:

.NET

classroom/snippets/ClassroomSnippets/ListCourseAliases.cs
using System;
using System.Collections.Generic;
using Google;
using Google.Apis.Auth.OAuth2;
using Google.Apis.Classroom.v1;
using Google.Apis.Classroom.v1.Data;
using Google.Apis.Services;

namespace ClassroomSnippets
{
    // Class to demonstrate the use of Classroom List Alias API
    public class ListCourseAliases
    {
        /// <summary>
        /// Retrieve the aliases for a course.
        /// </summary>
        /// <param name="courseId">Id of the course.</param>
        /// <returns>list of course aliases, null otherwise.</returns>
        public static List<CourseAlias> ClassroomListAliases(string courseId)
        {
            try
            {
                /* Load pre-authorized user credentials from the environment.
                 TODO(developer) - See https://developers.google.com/identity for 
                 guides on implementing OAuth2 for your application. */
                GoogleCredential credential = GoogleCredential.GetApplicationDefault()
                    .CreateScoped(ClassroomService.Scope.ClassroomCourses);

                // Create Classroom API service.
                var service = new ClassroomService(new BaseClientService.Initializer
                {
                    HttpClientInitializer = credential,
                    ApplicationName = "Classroom Snippets"
                });

                string pageToken = null;
                var courseAliases = new List<CourseAlias>();

                do
                {
                    // List of aliases of specified course
                    var request = service.Courses.Aliases.List(courseId);
                    request.PageSize = 100;
                    request.PageToken = pageToken;
                    var response = request.Execute();
                    courseAliases.AddRange(response.Aliases);
                    pageToken = response.NextPageToken;
                } while (pageToken != null);

                if (courseAliases.Count == 0)
                {
                    Console.WriteLine("No aliases found.");
                }
                else
                {
                    Console.WriteLine("Aliases:");
                    foreach (var courseAlias in courseAliases)
                    {
                        Console.WriteLine(courseAlias.Alias);
                    }
                }
                return courseAliases;
            }
            catch (Exception e)
            {
                // TODO(developer) - handle error appropriately
                if (e is AggregateException)
                {
                    Console.WriteLine("Credential Not found");
                }
                else if (e is GoogleApiException)
                {
                    Console.WriteLine("Course does not exist.");
                }

                else
                {
                    throw;
                }
            }
            return null;
        }
    }
}

Java

classroom/snippets/src/main/java/ListCourseAliases.java
String pageToken = null;
List<CourseAlias> courseAliases = new ArrayList<>();

try {
  // List of aliases of specified course
  do {
    ListCourseAliasesResponse response =
        service
            .courses()
            .aliases()
            .list(courseId)
            .setPageSize(100)
            .setPageToken(pageToken)
            .execute();
    courseAliases.addAll(response.getAliases());
    pageToken = response.getNextPageToken();
  } while (pageToken != null);

  if (courseAliases.isEmpty()) {
    System.out.println("No aliases found.");
  } else {
    System.out.println("Aliases:");
    for (CourseAlias courseAlias : courseAliases) {
      System.out.println(courseAlias.getAlias());
    }
  }
} catch (GoogleJsonResponseException e) {
  // TODO(developer) - handle error appropriately
  GoogleJsonError error = e.getDetails();
  if (error.getCode() == 404) {
    System.err.println("Course does not exist.\n");
  } else {
    throw e;
  }
}
return courseAliases;

Python

classroom/snippets/classroom_list_course_aliases.py
import google.auth
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError


def classroom_list_course_aliases(course_id):
  """
  Prints the list of the aliases of a specified course the user has access to.
  Load pre-authorized user credentials from the environment.
  TODO(developer) - See https://developers.google.com/identity
  for guides on implementing OAuth2 for the application.
  """

  creds, _ = google.auth.default()
  try:
    service = build("classroom", "v1", credentials=creds)
    course_aliases = []
    page_token = None

    while True:
      response = (
          service.courses()
          .aliases()
          .list(pageToken=page_token, courseId=course_id)
          .execute()
      )
      course_aliases.extend(response.get("aliases", []))
      page_token = response.get("nextPageToken", None)
      if not page_token:
        break

    if not course_aliases:
      print("No course aliases found.")

    print("Course aliases:")
    for course_alias in course_aliases:
      print(f"{course_alias.get('alias')}")
    return course_aliases
  except HttpError as error:
    print(f"An error occurred: {error}")
    return error


if __name__ == "__main__":
  classroom_list_course_aliases("course_id")