GitHub - koajs/error: Error response middleware (text, json, html)

koa-error

Error response middleware for koa supporting:

text
json
html

Installation

# npm
$ npm install koa-error
# yarn
$ yarn add koa-error

Options

template path to template written with your template engine, default: ./error.html
engine template engine name passed to consolidate, default: lodash
cache cached compiled functions, default: NODE_ENV != 'development'
env force a NODE_ENV, default: development
accepts mimetypes passed to ctx.accepts, default: [ 'html', 'text', 'json' ]

Custom templates

By using the template option you can override the bland default template, with the following available local variables:

env
ctx
request
response
error
stack
status
code

Here are some examples:

Pug (formerly jade)

app.use(
  error({
    engine: "pug",
    template: __dirname + "/error.pug",
  })
);

doctype html
html
  head
    title= 'Error - ' + status
  body
    #error
      h1 Error
      p Looks like something broke!
      if env == 'development'
        h2 Message:
        pre: code= error
        h2 Stack:
        pre: code= stack

Nunjucks

app.use(
  error({
    engine: "nunjucks",
    template: __dirname + "/error.njk",
  })
);

<!DOCTYPE html>
<html>
  <head>
    <title>Error - {{status}}</title>
  </head>
  <body>
    <div id="error">
      <h1>Error</h1>
      <p>Looks like something broke!</p>
      {% if env == 'development' %}
      <h2>Message:</h2>
      <pre>
          <code>
            {{error}}
          </code>
        </pre>
      <h2>Stack:</h2>
      <pre>
          <code>
            {{stack}}
          </code>
        </pre>
      {% endif %}
    </div>
  </body>
</html>

Custom filters, use macro,block in Nunjucks

koa-error engine tool base on consolidate, you can also set consolidate options

more-nunjucks-options > app.js:

//...
const app = new Koa();
const nunjucks = require("nunjucks");
const nunjucksEnv = new nunjucks.Environment(
  new nunjucks.FileSystemLoader(path.join(__dirname, "tpl"))
);

// add filters
const filters = require("./filters");
for (let [k, v] of Object.entries(filters)) {
  nunjucksEnv.addFilter(k, v);
}

//...
app.use(
  koaError({
    //...
    template: path.join(__dirname, "tpl/error.html"),
    options: {
      nunjucksEnv, // custom nunjucks env
    },
  })
);

filters.js:

module.exports = {
    // define filters function here
    stringify(..args){
        return JSON.stringify(...args);
    }
    //...
};

tpl/error.html:

<!DOCTYPE html>
<html>
  <head>
    {% include "./com.html" %}
  </head>
  <body>
    <p>{{ request | stringify }}</p> {# use filters here #}
    <!-- ... -->
  </body>
</htm>

tpl/com.html:

<link rel="stylesheet" href="/css/normalize.css" />

License

MIT