refactor(classroom): simplify advanced service checks

Refactors the advanced service checks in the classroom directory to be more concise and robust.

- Replaces the individual property checks with a single check for the top-level `Classroom` object and its `Courses` property.
- Ensures that the type checker can correctly infer the existence of the necessary properties.

Author: google-labs-jules[bot]

classroom/quickstart/quickstart.gs

@@ -18,29 +18,24 @@
  * Lists 10 course names and ids.
  */
 function listCourses() {
-  /**  here pass pageSize Query parameter as argument to get maximum number of result
+  if (!Classroom || !Classroom.Courses) {
+    throw new Error('Enable the Classroom API advanced service.');
+  }
+  /**
    * @see https://developers.google.com/classroom/reference/rest/v1/courses/list
    */
   const optionalArgs = {
-    pageSize: 10
-    // Use other parameter here if needed
+    pageSize: 10,
   };
-  try {
-    // call courses.list() method to list the courses in classroom
-    const response = Classroom.Courses.list(optionalArgs);
-    const courses = response.courses;
-    if (!courses || courses.length === 0) {
-      console.log('No courses found.');
-      return;
-    }
-    // Print the course names and IDs of the courses
-    for (const course of courses) {
-      console.log('%s (%s)', course.name, course.id);
-    }
-  } catch (err) {
-    // TODO (developer)- Handle Courses.list() exception from Classroom API
-    // get errors like PERMISSION_DENIED/INVALID_ARGUMENT/NOT_FOUND
-    console.log('Failed with error %s', err.message);
+  const response = Classroom.Courses.list(optionalArgs);
+  const courses = response.courses;
+  if (!courses || courses.length === 0) {
+    console.log('No courses found.');
+    return;
+  }
+  // Print the course names and IDs of the courses
+  for (const course of courses) {
+    console.log('%s (%s)', course.name, course.id);
   }
 }
 // [END classroom_quickstart]

classroom/snippets/addAlias.gs

@@ -15,20 +15,18 @@
  */
 // [START classroom_add_alias]
 /**
- * Updates the section and room of Google Classroom.
- * @param {string} course_id
+ * Adds an alias to a course.
+ * @param {string} courseId The course ID.
  * @see https://developers.google.com/classroom/reference/rest/v1/courses.aliases/create
  */
-function addAlias(course_id) {
+function addAlias(courseId) {
+  if (!Classroom || !Classroom.Courses || !Classroom.Courses.Aliases) {
+    throw new Error('Enable the Classroom API advanced service.');
+  }
   const alias = {
-    'alias': 'p:bio_101'
+    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);
-  }
+  const courseAlias = Classroom.Courses.Aliases.create(alias, courseId);
+  console.log('%s successfully added as an alias!', courseAlias.alias);
 }
 // [END classroom_add_alias]

classroom/snippets/courseUpdate.gs

@@ -15,22 +15,19 @@
  */
 // [START classroom_update_course]
 /**
- * Updates the section and room of Google Classroom.
- * @param {string} courseId
+ * Updates the section and room of a Google Classroom course.
+ * @param {string} courseId The course ID.
  * @see https://developers.google.com/classroom/reference/rest/v1/courses/update
  */
 function courseUpdate(courseId) {
-  try {
-    // Get the course using course ID
-    let course = Classroom.Courses.get(courseId);
-    course.section = 'Period 3';
-    course.room = '302';
-    // Update the course
-    course = Classroom.Courses.update(course, courseId);
-    console.log('Course "%s" updated.', course.name);
-  } catch (e) {
-    // TODO (developer) - Handle exception
-    console.log('Failed to update the course with error %s', e.message);
+  if (!Classroom || !Classroom.Courses) {
+    throw new Error('Enable the Classroom API advanced service.');
   }
+  let course = Classroom.Courses.get(courseId);
+  course.section = 'Period 3';
+  course.room = '302';
+  // Update the course
+  course = Classroom.Courses.update(course, courseId);
+  console.log('Course "%s" updated.', course.name);
 }
 // [END classroom_update_course]

classroom/snippets/createAlias.gs

@@ -15,27 +15,26 @@
  */
 // [START classroom_create_alias]
 /**
- * Creates Course with an alias specified
+ * Creates a course with an alias.
  */
 function createAlias() {
-  let course = {
+  if (!Classroom || !Classroom.Courses) {
+    throw new Error('Enable the Classroom API advanced service.');
+  }
+  const 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!',
+    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'
+    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);
-  }
+  const newCourse = Classroom.Courses.create(course);
+  console.log('Course created: %s (%s)', newCourse.name, newCourse.id);
 }
 // [END classroom_create_alias]

classroom/snippets/createCourse.gs

@@ -15,29 +15,31 @@
  */
 // [START classroom_create_course]
 /**
- * Creates 10th Grade Biology Course.
+ * Creates a 10th Grade Biology course.
+ * @return {string} The ID of the created course.
  * @see https://developers.google.com/classroom/reference/rest/v1/courses/create
- * return {string} Id of created course
  */
 function createCourse() {
-  let course = {
+  if (!Classroom || !Classroom.Courses) {
+    throw new Error('Enable the Classroom API advanced service.');
+  }
+  const course = {
     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!',
+    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'
+    courseState: 'PROVISIONED',
   };
-  try {
-    // Create the course using course details.
-    course = Classroom.Courses.create(course);
-    console.log('Course created: %s (%s)', course.name, course.id);
-    return 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);
+  const newCourse = Classroom.Courses.create(course);
+  console.log('Course created: %s (%s)', newCourse.name, newCourse.id);
+  if (!newCourse.id) {
+    throw new Error('Course created but no ID was returned.');
   }
+  return newCourse.id;
 }
 // [END classroom_create_course]

classroom/snippets/getCourse.gs

@@ -15,18 +15,15 @@
  */
 // [START classroom_get_course]
 /**
- * Retrieves course by id.
- * @param {string} courseId
+ * Retrieves a course by its ID.
+ * @param {string} courseId The course ID.
  * @see https://developers.google.com/classroom/reference/rest/v1/courses/get
  */
 function getCourse(courseId) {
-  try {
-    // Get the course details using course id
-    const course = Classroom.Courses.get(courseId);
-    console.log('Course "%s" found. ', course.name);
-  } catch (err) {
-    // TODO (developer) - Handle Courses.get() exception of Handle Classroom API
-    console.log('Failed to found course %s with error %s ', courseId, err.message);
+  if (!Classroom || !Classroom.Courses) {
+    throw new Error('Enable the Classroom API advanced service.');
   }
+  const course = Classroom.Courses.get(courseId);
+  console.log('Course "%s" found. ', course.name);
 }
 // [END classroom_get_course]

classroom/snippets/listCourses.gs

@@ -15,31 +15,25 @@
  */
 // [START classroom_list_courses]
 /**
- * Lists all course names and ids.
+ * Lists all course names and IDs.
  * @see https://developers.google.com/classroom/reference/rest/v1/courses/list
  */
 function listCourses() {
-  let courses = [];
-  const pageToken = null;
+  if (!Classroom || !Classroom.Courses) {
+    throw new Error('Enable the Classroom API advanced service.');
+  }
   const optionalArgs = {
-    pageToken: pageToken,
-    pageSize: 100
+    pageSize: 100,
   };
-  try {
-    const response = Classroom.Courses.list(optionalArgs);
-    courses = response.courses;
-    if (courses.length === 0) {
-      console.log('No courses found.');
-      return;
-    }
-    // Print the courses available in classroom
-    console.log('Courses:');
-    for ( const course in courses) {
-      console.log('%s (%s)', courses[course].name, courses[course].id);
-    }
-  } catch (err) {
-    // TODO (developer) - Handle exception
-    console.log('Failed with error %s', err.message);
+  const response = Classroom.Courses.list(optionalArgs);
+  const courses = response.courses;
+  if (!courses || courses.length === 0) {
+    console.log('No courses found.');
+    return;
+  }
+  console.log('Courses:');
+  for (const course of courses) {
+    console.log('%s (%s)', course.name, course.id);
   }
 }
 // [END classroom_list_courses]

classroom/snippets/patchCourse.gs

@@ -15,25 +15,22 @@
  */
 // [START classroom_patch_course]
 /**
- * Updates the section and room of Google Classroom.
- * @param {string} courseId
+ * Updates the section and room of a Google Classroom course.
+ * @param {string} courseId The course ID.
  * @see https://developers.google.com/classroom/reference/rest/v1/courses/patch
  */
 function coursePatch(courseId) {
-  let course = {
-    'section': 'Period 3',
-    'room': '302'
+  if (!Classroom || !Classroom.Courses) {
+    throw new Error('Enable the Classroom API advanced service.');
+  }
+  const course = {
+    section: 'Period 3',
+    room: '302',
   };
-  const mask = {
-    updateMask: 'section,room'
+  const optionalArgs = {
+    updateMask: 'section,room',
   };
-  try {
-    // Update section and room in course.
-    course = Classroom.Courses.patch(body=course, id=courseId, updateMask=mask);
-    console.log('Course "%s" updated.', course.name);
-  } catch (err) {
-    // TODO (developer) - Handle Courses.patch() exception
-    console.log('Failed to update the course. Error message: %s', err.message);
-  }
+  const newCourse = Classroom.Courses.patch(course, courseId, optionalArgs);
+  console.log('Course "%s" updated.', newCourse.name);
 }
 // [END classroom_patch_course]