feat: Live enrollment count

apps/backend/package.json

@@ -38,6 +38,7 @@
     "@graphql-tools/utils": "^10.3.2",
     "@keyv/redis": "^3.0.1",
     "@repo/common": "*",
+    "@repo/sis-api": "*",
     "compression": "^1.7.4",
     "connect-redis": "^7.1.1",
     "cors": "^2.8.5",

apps/backend/src/modules/enrollment/controller.ts

@@ -0,0 +1,48 @@
+import { SectionModel, SectionType, TermModel } from "@repo/common";
+import { ClassesAPI } from "@repo/sis-api/classes";
+
+import { config } from "../../config";
+import { Semester } from "../../generated-types/graphql";
+import { formatSection } from "../class/formatter";
+
+export const getEnrollment = async (
+  year: number,
+  semester: Semester,
+  subject: string,
+  courseNumber: string,
+  number: string
+) => {
+  const term = await TermModel.findOne({
+    name: `${year} ${semester}`,
+  });
+
+  if (!term) throw new Error("Term not found");
+
+  const section = await SectionModel.findOne({
+    "class.session.term.id": term.id,
+    "class.course.subjectArea.code": subject,
+    "class.course.catalogNumber.formatted": courseNumber,
+    number: number,
+  });
+
+  if (!section) throw new Error("Section not found");
+
+  const client = new ClassesAPI();
+
+  const response = await client.v1.getClassSectionByTermAndSectionIdUsingGet(
+    section.id,
+    { "term-id": term.id },
+    {
+      headers: {
+        app_key: config.sis.CLASS_APP_KEY,
+        app_id: config.sis.CLASS_APP_ID,
+      },
+    }
+  );
+
+  const raw = response.data.apiResponse?.response.classSections?.[0];
+
+  if (!raw) throw new Error("Something went error");
+
+  return formatSection(raw as unknown as SectionType);
+};

apps/backend/src/modules/enrollment/index.ts

@@ -0,0 +1,7 @@
+import resolver from "./resolver";
+import typeDef from "./typedefs/enrollment";
+
+export default {
+  resolver,
+  typeDef,
+};

apps/backend/src/modules/enrollment/resolver.ts

@@ -0,0 +1,23 @@
+import { getEnrollment } from "./controller";
+import { EnrollmentModule } from "./generated-types/module-types";
+
+const resolvers: EnrollmentModule.Resolvers = {
+  Query: {
+    enrollment: async (
+      _,
+      { year, semester, subject, courseNumber, number }
+    ) => {
+      const enrollment = await getEnrollment(
+        year,
+        semester,
+        subject,
+        courseNumber,
+        number
+      );
+
+      return enrollment as unknown as EnrollmentModule.Section;
+    },
+  },
+};
+
+export default resolvers;

apps/backend/src/modules/enrollment/typedefs/enrollment.ts

@@ -0,0 +1,13 @@
+import { gql } from "graphql-tag";
+
+export default gql`
+  type Query {
+    enrollment(
+      year: Int!
+      semester: Semester!
+      subject: String!
+      courseNumber: String!
+      number: String!
+    ): Section!
+  }
+`;

apps/backend/src/modules/index.ts

@@ -4,12 +4,23 @@ import Catalog from "./catalog";
 import Class from "./class";
 import Common from "./common";
 import Course from "./course";
+import Enrollment from "./enrollment";
 import Grade from "./grade";
 import Schedule from "./schedule";
 import Term from "./term";
 import User from "./user";
 
-const modules = [User, Grade, Catalog, Common, Schedule, Term, Course, Class];
+const modules = [
+  User,
+  Grade,
+  Catalog,
+  Common,
+  Schedule,
+  Term,
+  Course,
+  Class,
+  Enrollment,
+];
 
 export const resolvers = merge(modules.map((module) => module.resolver));