Example for http oak middleware with crud and sqlite DB

examples/http_routes_oak_crud_middleware_with_sqlite3_db.ts

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+/**
+ * @title HTTP server: Performing CRUD operations using SQLite3
+ * @difficulty intermediate
+ * @tags web, cli, deploy
+ * @run -A <url>
+ * @group Network
+ *
+ * An example of a HTTP server for CRUD routes with oak middleware framework and SQLite3 database.
+ * It demonstrates the CRUD(Create, Read, Update and Delete) operations on file-based SQLite Database using HTTP methods (Get, Post, Put, Delete, Options)
+ */
+
+import { Application, Router } from "https://deno.land/x/[email protected]/mod.ts";
+import { Database } from "jsr:@db/[email protected]";
+
+// Open a database from file, creates if doesn't exist. here the 'people.db' is a file-based database
+const peopleDb = new Database("people.db");
+
+// Create Table "people" if not exists with schema as shown below
+peopleDb.exec(
+  "CREATE TABLE IF NOT EXISTS people (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT not null,age INTEGER not null)",
+);
+// logs the DB creation status
+console.log("People table created successfully ");
+
+const app = new Application();
+const router = new Router();
+const PORT = "8369";
+// Create person record into people database
+router.post("/people", async (ctx) => {
+  const { name, age } = await (await ctx.request.body("json")).value;
+  const result = await peopleDb.prepare(
+    "INSERT INTO people (name, age) VALUES (?,?)",
+  )
+    .run(name, age);
+  ctx.response.status = 201;
+  ctx.response.body = { id: result.lastInsertRowId, name, age };
+});
+
+// Read all records from people database
+router.get("/people", async (ctx) => {
+  const users = await peopleDb.prepare("SELECT * FROM people").all();
+  ctx.response.body = users;
+});
+
+// Updates person record in people database (name value is optional)
+router.put("/people/:id", async (ctx) => {
+  const id = ctx.params.id;
+  const { name, age } = await (await ctx.request.body("json")).value;
+  let result = 0;
+  if (name) {
+    result = await peopleDb.prepare(
+      "UPDATE people SET name =?, age=? WHERE id = ?",
+    )
+      .run(name, age, id);
+  } else {
+    result = await peopleDb.prepare(
+      "UPDATE people SET age=? WHERE id = ?",
+    )
+      .run(age, id);
+  }
+  ctx.response.body = result > 0
+    ? { message: "person updated successfully as requested" }
+    : { message: "Failure in update operation" };
+});
+
+// Delete person record from people database
+router.delete("/people/:id", async (ctx) => {
+  const result = await peopleDb.prepare("DELETE FROM people WHERE id = ?").run(
+    ctx.params.id,
+  );
+  ctx.response.body = result > 0
+    ? { message: "person removed successfully as requested" }
+    : { message: "Failure in deletion operation" };
+});
+
+// Health check endpoint
+router.options("/healthz", async (ctx) => {
+  ctx.response.body = { message: `health check verified` };
+});
+
+app.use(router.routes());
+app.use(router.allowedMethods());
+console.log(`Server is running on http://localhost:${PORT}`);
+await app.listen({ port: PORT });
+// Export the app instance for testing
+export default app;