devserver

node-devserver

A simple development server geared towards front-end developers and ADD (Api Driven Development) applications.

What's it for

For ADD applications front-end developers generally have no need for a full stack development environment, so a lot of front-end developers use a combination of a local http instance for static content, and a http proxy that forwards to the back-end.

node-devserver combines these two into one.

How it works

When a request comes in node-devserver will first try to serve the request from the local filesystem, and if unsuccessfull proxy the request to a remote server. For example: let's say we get make a request to http://some.domain.local/a/file.ext (asuming that some.domain.local is pointing to our local machine) - node-devserver will try to serve the file from these locations (in order)

• root/some.domain.com/a/file.ext
• root/domain.com/a/file.ext
• root/com/a/file.ext
• root/a/file.ext

If none of these work the request will be proxied to a remote server.

Configuration

The node-devserver configuration file is basically an array of middlewares to load (in order). And example configuraton file could look like this:

[{
    "module" : "./middleware/frontend",
    "arguments" : [ "root" ]
}, {
    "module" : "./middleware/backend",
    "arguments" : [{
        "regexp" : "^(?<uat>cns-etuat-\\d+)\\.(?<vhost>.+)",
        "proxy" : {
            "host" : "${uat}.remote",
            "port" : 80
        }
    }]
}]

frontend module configuration

The frontend middleware is responsible for serving local files.

The configuration is quite straight forward - arguments is an array of strings that point out the location(s) where static files are served from.

backend module configuration

{
    "regexp" : "^(?<uat>cns-etuat-\\d+)\\.(?<vhost>.+)",
    "proxy" : {
        "host" : "${uat}.remote",
        "port" : 80
    }
}

The backend middleware matches url's to remote servers.

Options are tried in order like this:

• parse regexp using XRegExp
• match request agains regexp and store capture
• replace placeholders with captured elements
• proxy request using the proxy argument