Unable to extend the app's context in Koa@2

[alewaros]

Trying to extend the context of the application since migrating to koa@2 throws this error:

TypeError: Cannot set property 'property_name' of #<Object> which has only a getter

A small example code

import Koa from 'koa';

const app = new Koa();
app.context.host = process.env.HOST || '0.0.0.0';
app.context.port = process.env.PORT || 8080;

[menems]

Hi,

The host property on the context is the host of the request object. not the host of your running server instance.

if you want to change your host:port you have to change it on the http listen function.

[alewaros]

It was just as an example that I picked the host port here. My bad. But any other parameters throws an error when trying to set something to context.

[dead-horse]

context.host a setter/getter, so if you want to override it, try:

Object.defineProperty(app.context, 'host', {
 get: function() {
   return '0.0.0.0'
 },
});

[tejasmanohar]

#605

[jonathanong]

would es6 classes even solve this issue?

[PlasmaPower]

I don't think so, as delegate is still used for Request and Response.

[jonathanong]

added docs here: e61d545

make a PR if you have any suggestions!