Add months and latest months from DB

src/index.ts

@@ -10,6 +10,7 @@ import {
   getCOEResultByMonth,
   groupMonthsByYear,
 } from "./lib";
+import { getLatestMonth } from "./lib/getLatestMonth";
 import { type Car, type COEResult, FUEL_TYPE } from "./types";
 
 const app = new Hono();
@@ -79,6 +80,23 @@ app.get("/months", async (c) => {
   return c.json(sortedMonths);
 });
 
+app.get("/months/latest", async (c) => {
+  const collection = c.req.query("collection");
+  const dbCollections = ["cars", "coe"];
+
+  const latestMonthObj = {};
+
+  if (collection) {
+    latestMonthObj[collection] = await getLatestMonth(collection);
+  } else {
+    for (const dbCollection of dbCollections) {
+      latestMonthObj[dbCollection] = await getLatestMonth(dbCollection);
+    }
+  }
+
+  return c.json(latestMonthObj);
+});
+
 showRoutes(app);
 
 export const handler = handle(app);

src/lib/getCOEResultByMonth.ts

@@ -1,25 +1,12 @@
 import db from "../config/db";
+import { getLatestMonth } from "./getLatestMonth";
 import type { COEResult } from "../types";
 
 export const getCOEResultByMonth = async (month?: string) => {
   let selectedMonth = month;
 
   if (!month) {
-    const latestMonthFromDb = await db
-      .collection<COEResult>("coe")
-      .aggregate([
-        {
-          $group: {
-            _id: null,
-            latestMonth: { $max: "$month" },
-          },
-        },
-        { $sort: { month: -1 } },
-        { $limit: 1 },
-      ])
-      .next();
-
-    selectedMonth = latestMonthFromDb.latestMonth;
+    selectedMonth = await getLatestMonth("coe");
   }
 
   return db

src/lib/getLatestMonth.ts

@@ -0,0 +1,19 @@
+import db from "../config/db";
+
+export const getLatestMonth = async (collection: string) => {
+  const latestMonthFromDb = await db
+    .collection(collection)
+    .aggregate([
+      {
+        $group: {
+          _id: null,
+          latestMonth: { $max: "$month" },
+        },
+      },
+      { $sort: { month: -1 } },
+      { $limit: 1 },
+    ])
+    .next();
+
+  return latestMonthFromDb.latestMonth;
+};

src/types/index.ts

@@ -29,3 +29,8 @@ export interface UpdateParams {
   zipUrl: string;
   keyFields: string[];
 }
+
+export interface LatestMonth {
+  _id: null;
+  latestMonth: string;
+}