feat: populate database function

.gitignore

@@ -3,3 +3,4 @@ node_modules/
 public/
 test/
 data/
+words.txt

src/db/index.ts

@@ -0,0 +1,79 @@
+import { logError, logSuccess, projectRoot } from "../utils";
+import fs from "fs";
+import path from "path";
+import { Client, QueryResult } from "pg";
+
+export const tableExists = async (db: Client): Promise<boolean> => {
+    const result = await db
+        .query(
+            "SELECT EXISTS (SELECT * FROM information_schema.tables WHERE table_name = 'words');"
+        )
+        .catch((err) => err);
+
+    return result.rows[0].exists;
+};
+
+// used for generating param query string
+// expand(rowCount: 3, columnCount: 2) returns "($1, $2), ($3, $4), ($5, $6)"
+function expand(rowCount: number, columnCount = 1, startAt = 1) {
+    var index = startAt;
+    return Array(rowCount)
+        .fill(0)
+        .map(
+            (v) =>
+                `(${Array(columnCount)
+                    .fill(0)
+                    .map((v) => `$${index++}`)
+                    .join(", ")})`
+        )
+        .join(", ");
+}
+
+export const populateDB = async (db: Client) => {
+    let filename = "words.txt";
+    let filepath = path.join(projectRoot, filename);
+
+    // check for source file
+    if (!fs.existsSync(filepath)) {
+        logError(
+            "Could not find `okiba/words.txt` for populating the database!\n"
+        );
+        process.exit(1);
+    }
+
+    await db
+        .query(
+            "CREATE TABLE words (id SERIAL PRIMARY KEY, val VARCHAR NOT NULL, taken BOOLEAN DEFAULT 'f');"
+        )
+        .catch((err) => err);
+
+    fs.readFile(
+        filepath,
+        { encoding: "utf-8" },
+        async (err: Error | null, data: string) => {
+            if (err != null) {
+                logError(err.message);
+                throw err;
+            }
+
+            let arr: Array<string> = data.split("\r\n");
+
+            // 1k entries per query
+            const chunkSize = 1000;
+            for (let i = 0; i < arr.length; i += chunkSize) {
+                const chunk: Array<string> = arr.slice(i, i + chunkSize);
+
+                const queryStr = {
+                    text: `INSERT INTO words (val) VALUES ${expand(
+                        chunk.length
+                    )}`,
+                    values: chunk,
+                };
+
+                await db.query(queryStr);
+            }
+        }
+    );
+
+    logSuccess("Successfully populated the database!");
+};

src/main.ts

@@ -3,14 +3,15 @@ import dotenv from "dotenv";
 import BinRouter from "./routes/bin";
 import { Client, Pool } from "pg";
 import { createDataDir, errorHandler, logError, logSuccess } from "./utils";
+import { tableExists, populateDB } from "./db";
 
 const main = async () => {
     dotenv.config();
     createDataDir();
 
     // init db
-    const pool = await new Pool();
+    const pool = new Pool();
-    const client = await new Client();
+    const client = new Client();
 
     client
         .connect()
@@ -22,6 +23,12 @@ const main = async () => {
             throw err;
         });
 
+    // check if `words` table exists
+    // else populate db with `/okiba/words.txt`
+    if (!(await tableExists(client))) {
+        await populateDB(client);
+    }
+
     // start server
     const app: Express = express();
     const port = process.env.PORT;

src/routes/bin.ts

@@ -18,7 +18,7 @@ export default function BinRouter(db: Pool) {
         const word: Word | undefined = await getAvailableWord(db);
 
         if (word != undefined) {
-            await fs.writeFile(
+            fs.writeFile(
                 path.join(projectRoot, "data", word.val + ".txt"),
                 body,
                 (err) => err

src/utils/index.ts

@@ -6,6 +6,7 @@ import fs from "fs";
 // logs
 export const logError = (msg: string) => console.error(chalk.bold.red(msg));
 export const logSuccess = (msg: string) => console.log(chalk.bold.green(msg));
+export const logWarning = (msg: string) => console.log(chalk.bold.yellow(msg));
 
 export const projectRoot = path.join(__dirname, "..", "..");