What are some examples of middleware in Koa?

Can you give me some examples of middleware in Koa?

Sure! Koa middleware functions are used to handle requests and responses. For example, you can use middleware for logging requests, handling errors, or parsing request bodies.

What is a simple logging middleware example?

A simple logging middleware in Koa could look like this:

app.use(async (ctx, next) => {
  console.log(`${ctx.method} ${ctx.url}`);
  await next();
});

How about error handling middleware?

For error handling, you can create middleware like this:

app.use(async (ctx, next) => {
  try {
    await next();
  } catch (err) {
    ctx.status = err.status || 500;
    ctx.body = { message: err.message };
  }
});

Can you show me an example of using a third-party middleware?

Certainly! You can use koa-bodyparser for parsing request bodies:

const bodyParser = require('koa-bodyparser');
app.use(bodyParser());