Other body types

[franciscop]

While in the documentation it states that the body will return a JSON object if the body is set to an object, I found out that arrays also work the same way:

ctx.body = ['foo', 'bar'];

This is awesome, but it might be a bug since in the code for that part the leftovers are treated as JSON:

set body(val) {
    // ...
    if ('string' == typeof val) // ...
    if (Buffer.isBuffer(val)) // ...
    if ('function' == typeof val.pipe) // ...
    
    // Everything else
    this.remove('Content-Length');
    this.type = 'json';
}

Notably this makes other things work:

app.use(ctx => {
  ctx.body = false;
});

But some other things won't:

app.use(ctx => {
  ctx.body = () => {
    console.log('Hello there!');
  };
});

Is this an intended feature? Everything that is not one of the above is just treated as JSON?

Notably in counter-intuitive examples, this will work and return a json {} with a status code 200 (I know about throw(), just pointing out this works not as expected and might be confusing):

app.use(ctx => {
  ctx.body = new Error('I work!');
});

[jonathanong]

we didn't bother guarding against everything a dev could put as a response body. returning a function simply doesn't make sense. returning a boolean could make sense. an error works, but it doesn't work as intended as some properties of an error are not enumerable.

personally, i would just add middleware in the app that asserts body types per app. the framework should remain minimal.

app.use(async (ctx, next) => {
  await next()

  ctx.assert.equal('object', typeof ctx, 500, 'some dev did something wrong')
})

this is only a few lines of code and could be tailored to each app