Add an endpoint to retrieve assignments

Author: Dlurak

src/routes/assignments/index.ts

@@ -1,6 +1,7 @@
 import Elysia from "elysia";
 import { createAssignment } from "./create";
+import { listAssignments } from "./list";
 
-export const assignmentsRouter = new Elysia({ prefix: "/assignments" }).use(
-	createAssignment,
-);
+export const assignmentsRouter = new Elysia({ prefix: "/assignments" })
+	.use(listAssignments)
+	.use(createAssignment);

src/routes/assignments/list.ts

@@ -0,0 +1,122 @@
+import e from "@edgedb";
+import { DATABASE_READ_FAILED } from "constants/responses";
+import Elysia, { t } from "elysia";
+import { HttpStatusCode } from "elysia-http-status-code";
+import { client } from "index";
+import { removeDuplicates } from "utils/arrays/duplicates";
+import { filterTruthy } from "utils/arrays/filter";
+import { areSameValue } from "utils/arrays/general";
+import { merge } from "utils/arrays/merge";
+import { normalDateToCustom } from "utils/dates/customAndNormal";
+import { multipleClasses } from "utils/db/classes";
+import { promiseResult } from "utils/errors";
+import { responseBuilder } from "utils/response";
+import { split } from "utils/strings/split";
+import { z } from "zod";
+
+const classesSchema = z.array(z.string().min(1)).nonempty();
+
+export const listAssignments = new Elysia().use(HttpStatusCode()).get(
+	"/",
+	async ({ query, set, httpStatus }) => {
+		const classesResult = classesSchema.safeParse(
+			filterTruthy(split(query.classes)),
+		);
+		if (!classesResult.success) {
+			set.status = httpStatus.HTTP_400_BAD_REQUEST;
+			return responseBuilder("error", {
+				error: "Classes must be an array of strings",
+			});
+		}
+		const classNames = removeDuplicates(classesResult.data).sort();
+
+		const assignmentsQuery = (limit: number, offset: number) =>
+			e.select(e.Assignment, (a) => {
+				const classMatches = e.op(a.class.name, "in", e.set(...classNames));
+				const schoolMatches = e.op(a.class.school.name, "=", query.school);
+
+				// -1 disables the limit
+				const internalLimit = limit === -1 ? undefined : limit;
+
+				return {
+					filter: e.op(classMatches, "and", schoolMatches),
+					limit: internalLimit,
+					offset,
+
+					subject: true,
+					description: true,
+					dueDate: true,
+					fromDate: true,
+					updates: true,
+					updatedBy: () => ({ username: true }),
+				};
+			});
+
+		const result = await promiseResult(() => {
+			return client.transaction(async (tx) => {
+				const assignments = await assignmentsQuery(
+					query.limit,
+					query.offset,
+				).run(tx);
+				const count = await e.count(assignmentsQuery(-1, 0)).run(tx);
+				const classes = await multipleClasses({
+					schoolName: query.school,
+					classNames: classNames,
+				})
+					.run(tx)
+					.then((c) => (c ? c.map((cl) => cl.name).sort() : []));
+
+				return { assignments, count, classes };
+			});
+		});
+
+		if (result.isError) {
+			set.status = httpStatus.HTTP_500_INTERNAL_SERVER_ERROR;
+			return DATABASE_READ_FAILED;
+		}
+
+		if (!areSameValue(result.data.classes, classNames)) {
+			set.status = httpStatus.HTTP_404_NOT_FOUND;
+			return responseBuilder("error", {
+				error: "Not all of the specified classes exist",
+			});
+		}
+
+		const formatted = result.data.assignments.map((assignment) => {
+			const updates = merge(
+				{
+					key: "user",
+					array: assignment.updatedBy.map((u) => u.username),
+				},
+				{
+					key: "timestamp",
+					array: assignment.updates.map((d) => d.getTime()),
+				},
+			);
+
+			return {
+				subject: assignment.subject,
+				description: assignment.description,
+				from: normalDateToCustom(assignment.fromDate),
+				due: normalDateToCustom(assignment.dueDate),
+				updates,
+			};
+		});
+
+		return responseBuilder("success", {
+			message: "Received data",
+			data: {
+				totalCount: result.data.count,
+				assignments: formatted,
+			},
+		});
+	},
+	{
+		query: t.Object({
+			school: t.String({ minLength: 1 }),
+			classes: t.String({ minLength: 1 }),
+			limit: t.Numeric({ minimum: -1, default: 50 }),
+			offset: t.Numeric({ minimum: 0, default: 0 }),
+		}),
+	},
+);

src/utils/arrays/duplicates.ts

@@ -0,0 +1,8 @@
+/**
+ * Remove duplicates from an array
+ * The original array will not be modified
+ * The order will not be changed
+ */
+export const removeDuplicates = <T>(arr: T[]) => {
+	return arr.filter((val, i, self) => self.indexOf(val) === i);
+};

src/utils/arrays/filter.ts

@@ -0,0 +1,4 @@
+/**
+ * Filter out all falsy values from an array without modifying it
+ */
+export const filterTruthy = <T>(array: T[]) => array.filter((i) => i);

src/utils/arrays/general.ts

@@ -0,0 +1,11 @@
+export const areSameValue = <T>(first: T[], second: T[]): boolean => {
+	if (first.length !== second.length) return false;
+	if (first.length === 0) return true;
+
+	const firstArrFirst = first[0];
+	const secondArrFirst = first[0];
+
+	if (firstArrFirst !== secondArrFirst) return false;
+
+	return areSameValue(first.slice(1), second.slice(1));
+};

src/utils/arrays/merge.ts

@@ -0,0 +1,34 @@
+interface MergeInput<T, K extends string> {
+	array: T[];
+	key: K;
+}
+
+type MergeResult<F, FK extends string, S, SK extends string> = {
+	[K in FK]: F | undefined;
+} & {
+	[K in SK]: S | undefined;
+};
+
+/**
+ * Merge two arrays into one
+ */
+export const merge = <F, FK extends string, S, SK extends string>(
+	first: MergeInput<F, FK>,
+	second: MergeInput<S, SK>,
+) => {
+	type Rec = MergeResult<F, FK, S, SK>;
+
+	const mergedArray: Rec[] = [];
+	const maxLength = Math.max(first.array.length, second.array.length);
+
+	for (let i = 0; i < maxLength; i++) {
+		const entries = [
+			[first.key, first.array[i]],
+			[second.key, second.array[i]],
+		] as const;
+
+		mergedArray.push(Object.fromEntries(entries) as Rec);
+	}
+
+	return mergedArray;
+};

src/utils/db/classes.ts

@@ -62,3 +62,18 @@ export async function doesClassExist(props: ClassIdentifier) {
 
 	return !!result.data;
 }
+
+export const multipleClasses = (props: {
+	schoolName: string;
+	classNames: string[];
+}) => {
+	return e.select(e.Class, (c) => {
+		const nameMatches = e.op(c.name, "in", e.set(...props.classNames));
+		const schoolMatches = e.op(c.school.name, "=", props.schoolName);
+
+		return {
+			filter: e.op(nameMatches, "and", schoolMatches),
+			name: true,
+		};
+	});
+};

src/utils/strings/split.ts

@@ -0,0 +1,5 @@
+/**
+ * Split a string at commas but not escaped ones
+ */
+export const split = (str: string) =>
+	str.split(/(?<!\\),/).map((s) => s.replace(/\\,/g, ","));

tests/array.test.ts

@@ -0,0 +1,72 @@
+import { describe, expect, it } from "bun:test";
+import { removeDuplicates } from "utils/arrays/duplicates";
+import { areSameValue } from "utils/arrays/general";
+import { merge } from "utils/arrays/merge";
+
+describe("merge", () => {
+	it("same length", () => {
+		const result = merge(
+			{ key: "a", array: [1, 2, 3] },
+			{ key: "b", array: ["x", "y", "z"] },
+		);
+
+		expect(result).toEqual([
+			{ a: 1, b: "x" },
+			{ a: 2, b: "y" },
+			{ a: 3, b: "z" },
+		]);
+	});
+
+	it("works when the first one is longer", () => {
+		const result = merge(
+			{ key: "a", array: [1, 2, 3] },
+			{ key: "b", array: ["a"] },
+		);
+
+		expect(result).toEqual([
+			{ a: 1, b: "a" },
+			{ a: 2, b: undefined },
+			{ a: 3, b: undefined },
+		]);
+	});
+
+	it("works when the second one is longer", () => {
+		const result = merge(
+			{ key: "b", array: ["a"] },
+			{ key: "a", array: [1, 2, 3] },
+		);
+
+		expect(result).toEqual([
+			{ b: "a", a: 1 },
+			{ b: undefined, a: 2 },
+			{ b: undefined, a: 3 },
+		]);
+	});
+});
+
+describe("duplicates", () => {
+	it("does nothing when there'no duplicates", () => {
+		expect(removeDuplicates([1, 2, 3, 4])).toEqual([1, 2, 3, 4]);
+		expect(removeDuplicates(["a", "b", "c"])).toEqual(["a", "b", "c"]);
+	});
+
+	it("removes duplicates", () => {
+		expect(removeDuplicates([1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1])).toEqual([
+			1, 2,
+		]);
+		expect(
+			removeDuplicates(["ts", "rust", "linux", "i3", "linux", "js", "rust"]),
+		).toEqual(["ts", "rust", "linux", "i3", "js"]);
+	});
+});
+
+describe("same value", () => {
+	it("works for equal arrays", () => {
+		const testCases = [[], ["a", "a"], ["a", "b"], [1, 2], [1, 1]];
+
+		for (const tCase of testCases) {
+			// @ts-ignore
+			expect(areSameValue(tCase, tCase)).toBeTrue();
+		}
+	});
+});

tests/strings.test.ts

@@ -0,0 +1,15 @@
+import { describe, expect, it } from "bun:test";
+import { split } from "utils/strings/split";
+
+describe("split", () => {
+	it("splits at ,", () => {
+		const original = "value,value2,valu5,";
+		expect(split(original)).toEqual(["value", "value2", "valu5", ""]);
+		expect(original).toBe("value,value2,valu5,");
+	});
+
+	it("ignores escaped commas", () => {
+		const original = "this\\,is\\,;one,and\\,this\\,another";
+		expect(split(original)).toEqual(["this,is,;one", "and,this,another"]);
+	});
+});