refactor(server.ts): Optimize SQL param handling, add pagination logic

config/deno-kv.ts

@@ -100,7 +100,7 @@ function cleanSpecialCharacters(input: string): string {
   // Remove emojis and other special characters
   const cleanedString = encodedString.replace(
     /[\u{1F600}-\u{1F64F}\u{1F300}-\u{1F5FF}\u{1F680}-\u{1F6FF}\u{1F1E0}-\u{1F1FF}\u{2600}-\u{26FF}\u{2700}-\u{27BF}]/gu,
-    ""
+    "",
   );
 
   // Remove extra whitespace
@@ -133,7 +133,7 @@ export async function listenQueue(kv: Deno.Kv) {
                 Object.keys(msg.data.dataLayer.attributes).length < 5
               ) {
                 throw new Error(
-                  "Attributes are missing, undefined, or have fewer than 5 properties"
+                  "Attributes are missing, undefined, or have fewer than 5 properties",
                 );
               }
 
@@ -142,7 +142,7 @@ export async function listenQueue(kv: Deno.Kv) {
                 typeof msg.data.dataLayer.location !== "object"
               ) {
                 throw new Error(
-                  "Location is missing, undefined, or not an object"
+                  "Location is missing, undefined, or not an object",
                 );
               }
 
@@ -152,7 +152,7 @@ export async function listenQueue(kv: Deno.Kv) {
               const images = msg.data.images as { src: string }[];
               const isCondominium =
                 msg.data.dataLayer.attributes.attribute_set_name ===
-                "Condominium";
+                  "Condominium";
               const isHouse =
                 msg.data.dataLayer.attributes.attribute_set_name === "House";
               const isWarehouse =
@@ -173,8 +173,8 @@ export async function listenQueue(kv: Deno.Kv) {
                 };
 
                 const price = msg.data.dataLayer?.attributes?.price;
-                const priceFormatted =
-                  msg.data.dataLayer?.attributes?.price_formatted;
+                const priceFormatted = msg.data.dataLayer?.attributes
+                  ?.price_formatted;
 
                 await transaction.queryArray({
                   args: [price, priceFormatted, listing.id],
@@ -252,8 +252,9 @@ export async function listenQueue(kv: Deno.Kv) {
               const productOwnerName = msg.data.dataLayer?.product_owner_name;
               const location: Location = msg.data.dataLayer.location;
               const dataLayerAttributes = msg.data.dataLayer.attributes;
-              const offerTypeId =
-                dataLayerAttributes.offer_type === "Rent" ? 2 : 1;
+              const offerTypeId = dataLayerAttributes.offer_type === "Rent"
+                ? 2
+                : 1;
               const sellerIsTrusted = dataLayerAttributes?.seller_is_trusted;
               const locationData = await getLocation(transaction, {
                 ...location,
@@ -364,7 +365,8 @@ export async function listenQueue(kv: Deno.Kv) {
                   offerTypeId,
                   newProperty,
                 ],
-                text: `INSERT INTO Listing (title, url, project_name, description, is_scraped, address, price_formatted, price, offer_type_id, property_id)
+                text:
+                  `INSERT INTO Listing (title, url, project_name, description, is_scraped, address, price_formatted, price, offer_type_id, property_id)
                   VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10) RETURNING id`,
               });
 

server.ts

@@ -56,12 +56,10 @@ app.get("/api/properties", async (c: Context) => {
   const sqlParams = [
     parseInt(query.property_type_id),
     parseInt(query.listing_type_id),
-    parseInt(query.page_size),
-    offset,
   ];
 
   // Initialize the parameter counter for dynamic parameter numbering
-  let paramCounter = 5;
+  let paramCounter = 3;
 
   // Function to add a new condition to the WHERE clause
   // deno-lint-ignore no-explicit-any
@@ -103,7 +101,7 @@ app.get("/api/properties", async (c: Context) => {
   console.log({ sqlWhereClause, sqlParams, nextParamCounter: paramCounter });
 
   const postgres = await client.queryObject({
-    args: sqlParams,
+    args: [...sqlParams, parseInt(query.page_size), offset],
     text: `
           SELECT
               l.id AS listing_id,
@@ -169,10 +167,46 @@ app.get("/api/properties", async (c: Context) => {
               LEFT JOIN Listing_Area ar ON p.listing_area_id = ar.id
           WHERE
               ${sqlWhereClause}
-          ORDER BY l.id DESC LIMIT $3 OFFSET $4;
+          ORDER BY l.id DESC LIMIT $${paramCounter} OFFSET $${paramCounter + 1};
+    `,
+  });
+
+  const recordCount = await client.queryObject({
+    args: sqlParams,
+    text: `
+      SELECT COUNT(*)::integer
+      FROM
+        Listing l
+        JOIN Property p ON l.property_id = p.id
+        LEFT JOIN Property_Type pt ON p.property_type_id = pt.property_type_id
+        LEFT JOIN Listing_Type lt ON l.offer_type_id = lt.listing_type_id
+        LEFT JOIN Warehouse_Type wt ON p.warehouse_type_id = wt.warehouse_type_id
+        LEFT JOIN Listing_Region rg ON p.listing_region_id = rg.id
+        LEFT JOIN Listing_City ct ON p.listing_city_id = ct.id
+        LEFT JOIN Listing_Area ar ON p.listing_area_id = ar.id
+      WHERE
+        ${sqlWhereClause}
     `,
   });
-  return c.json(postgres.rows);
+
+  const counterResult = recordCount.rows[0] as { count: number };
+  const totalListingRecords = counterResult.count;
+  const pageNo = parseInt(query.page);
+  const pageSize = parseInt(query.page_size);
+
+  const totalPages = Math.ceil(totalListingRecords / pageSize);
+  const nextPage = pageNo < totalPages ? pageNo + 1 : null;
+  const previousPage = pageNo > 1 ? pageNo - 1 : null;
+
+  return c.json({ 
+    data: postgres.rows,
+    total: totalListingRecords,
+    page: pageNo,
+    page_size: pageSize,
+    total_pages: totalPages,
+    next_page: nextPage,
+    previous_page: previousPage
+  });
 });
 
 app.post("/", async (c: Context) => {