How do I add to 'view options' in Express?

Question

I am learning to use Express. I want to do: ``` app.configure(function(){ app.set('views', __dirname + '/views'); app.set('view engine', 'jade'); app.set('view options', { layout: false }); /* asterisk */ app.use(express.bodyParser()); app.use(express.methodOverride()); app.use(app.router); /* dagger */ app.use(express.static(__dirname + '/public')); }); app.configure('development', function(){ app.use(express.errorHandler({ dumpExceptions: true, showStack: true })); app.use(express.logger('dev')); app.set('view options', { pretty: true }); /* asterisk */ }); ``` The additions I made were: - use 'layout:false' for Jade. - pretty-print the HTML in Jade. - turn on the logger, with the 'dev' format There are two problems: `/* asterisk */` when I set 'pretty: true' I am overriding my previous options, rather than adding to them. I.e., my program breaks unless I add `{ pretty: true, layout: false }` which feels redundant and can't be correct. How can I correct it so that I am only "modifyi…

Accepted Answer

I checked in the express source code and the `app.set` function simply assigns over top of any previous value it had. To get the behavior you're looking for you'll have to merge the `view options` object in subsequent calls. This means you'll probably have to jump through a couple of hoops. The connect package has a merge function that will work for this but to get it you'll have to include it in your `package.json`:

```
"dependencies": {
  "express": "2.5.5"
, "jade": ">= 0.0.1"
, "connect": "1.X"
}
```

You'll need to get the `utils` object from connect:

```
var utils = require('connect').utils;
```

`app.set(option)` with no value returns the current setting for the option so the second time you set `view option` you could do it this way:

```
app.set('view options', utils.merge(app.set('view options'), { pretty: true }));
```

As for the problem you're having with the logger, remember that app.use is adding pieces of middleware to a stack. As a request is being processed it calls each piece of middleware in the order they are originally configured and sometimes if a piece of middleware is able to fulfill its duty it will not pass control to subsequent middleware in the stack.

This is the case with the `router` middleware when it fulfills a request for the `'/'` url where `logger` is not subsequently run. The reason the request for `favicon.ico` shows up in the log stream is that none of the middleware was able to fulfill it (the `static` middleware would if you had a `public/favicon.ico` file) and processing falls through to the `logger` middleware.

To make your example work you'll need to define the `logger` middleware earlier in your stack, before the `router` middleware.

How do I add to 'view options' in Express?

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