Beeline

A laughably simplistic router for node.js

Currently works with node.js v0.3.1 and above

Goals

• Simple
• Unobtrusive
• Fairly Foolproof
• Easy to debug
• Fast

Examples

var bee = require("beeline");
var router = bee.route({ // Create a new router
    "/cheggit": function(req, res) {
        // Called when req.url === "/cheggit" or req.url === "/cheggit?woo=poo"
    },
    "/names/`last-name`/`first-name`": function(req, res, tokens, values) {
        // Called when req.url contains three parts, the first of is "name".
        // The parameter tokens is an object that maps token names to values.
        // For example if req.url === "/names/smith/will"
        //   then tokens ===  { "first-name": "will", "last-name": "smith" }
        //   and values === [ "will", "smith" ]
        //   also req.params === tokens
    },
    "/static/`path...`": function(req, res, tokens, values) {
        // Called when req.url starts with "/static/"
        // The parameter tokens is an object that maps token name to a value
        // The parameter values is a list of
        // For example if req.url === "/static/pictures/actors/smith/will.jpg"
        //   then tokens === { "path": "pictures/actors/smith/will.jpg" }
        //   and values === [ "pictures/actors/smith/will.jpg" ]
        //   also req.params === tokens
    },
    "/`user`/static/`path...`": function(req, res, tokens, values) {
        // Called when req.url contains at least three parts, the second of which
        // is "static".
        // The parameter tokens is an object that maps token names and value
        // For example if req.url === "/da-oozer/static/pictures/venkman.jpg"
        //   then tokens === { "user": "da-oozer", "path": "pictures/venkman.jpg" }
        //   and values === [ "da-oozer", "pictures/venkman.jpg" ]
        //   also req.params === tokens
    },
    "/blogs/`user-id: [a-z]{2}-\\d{5}`/`post-id: \\d+`": function(
        req, res, tokens, values
    ) {
        // Called when req.url starts with "/blogs/" and when the second and third
        // parts match /[a-z]{2}-\d{5}/ and /\d+/ respectiviely.
        // The parameter tokens is an object that maps token names and value
        // For example if req.url === "/blog/ab-12345/1783"
        //   then tokens === { "user-id": "ab-12345", "post-id": "1783" }
        //   and values === [ "ab-12345", "1783" ]
        //   also req.params === tokens
    },
    "r`^/actors/([\\w]+)/([\\w]+)$`": function(req, res, matches) {
        // Called when req.url matches this regex: "^/actors/([\\w]+)/([\\w]+)$"
        // An array of captured groups is passed as the third parameter
        // For example if req.url === "/actors/smith/will"
        //   then matches === [ "smith", "will" ]
    },
    "`404`": function(req, res) {
        // Called when no other route rule are matched
        //
        // This handler can later be called explicitly with router.missing
    },
    "`500`": function(req, res, err) {
        // Called when an exception is thrown by another router function
        // The error that caused the exception is passed as the third parameter
        // This _not_ guaranteed to catch all exceptions
        //
        // This handler can later be called explicitly with router.error
    }
});

router.add({ // Use `.add` to append new rules to a router 
    "/ /home r`^/index(.php|.html|.xhtml)?$`": function(req, res) {
        // Called when req.url === "/" or req.url === "/home"
        //    or req.url matches this regex: ^/index(.php|.html|.xhtml)?$
        //      (i.e. req.url === "/index.php" or req.url === "/index.html")
        // Note that any number of rules can be combined using a space.
        // All rules will call the same request handler when matched.
    },
    "/my-method": { // Method (aka verb) specific dispatch.  Note case matters.
        "GET": function(req, res) {
            // Called when req.url === "/my-method" and req.method === "GET"
        },
        "POST PUT": function(req, res) {
            // Called when req.url === "/my-method" and
            //  req.method === "POST" or req.method === "PUT"
            // Methods can be combined with a space like URL rules.
        },
        "any": function(req, res) {
            // Called when req.url === "/my-method" and req.method is not
            // "GET" or "POST"
        }
    },
    "`405`": function(req, res) {
        // Called when when a URL is specified but no corresponding method (aka verb)
        // matches.  For example, this handler would be executed if the "any" catch
        // all wasn't specified in the handler above and req.method === "HEAD"
        //
        // This handler can later be called explicitly with router.missingVerb
    },
    "/explicit-calls": function(req, res) { // If necessary you can reroute requests
        if(url.parse(req.url).query["item-name"] === "unknown") {
            // Calls the 404 (aka missing) handler:
            return router.missing(req, res, this);
            // The last parameter is optional.  It sets the this pointer in the
            // 404 handler.
        }
        
        if(url.parse(req.url).query["item-name"] === "an-error") {
            // Calls the 500 (aka error) handler:
            return router.error(req, res, err, this);
            // The last parameter is optional.  It sets the this pointer in the
            // 500 handler.
        }
        
        // Do normal request handling
    }
});

// Starts serve with routes defined above:
require("http").createServer(router).listen(8001);

See test/test.js for a working example.

The API

To start, simply store the beeline library in a local variable:

var bee = require("beeline");

The beeline library contains the following three methods:

• bee.route(routes): Used to create a new router. It returns a function called rtn_fn that takes ServerRequest and ServerResponse objects as parameters. The routes parameter is an objects that maps rules to handlers. See examples section for more details.

• bee.staticFile(path, mimeType[, maxage=31536000]): This is a utility method that is used to quickly expose static files. It returns a function called rtn_fn that takes ServerRequest and ServerResponse objects as parameters. When rtn_fn is called, the file contents located at path are served (via the ServerResponse) with the Content-Type set to the mimeType parameter. If the file at path does not exist a 404 is served. The optional maxage parameter is used to in the response's Cache-Control header. Also note that all Set-Cookie headers are removed. Here's an example of how you might use bee.staticFile:

  bee.route({
      "/robots.txt": bee.staticFile("./content/robots.txt", "text/plain")
  });

• bee.staticDir(path, mimeTypes[, maxage=31536000]): This is utility method is used to expose directories of files. It returns a function called rtn_fn that takes a ServerRequest object, a ServerResponse object, an optional third parameter, and an array of strings called matches as parameters. Whenever rtn_fn is called, the items of matches are joined together and then concatenated to path. The resulting string is assumed to be a path to a specific file. If this file exists, its contents are served (via the ServerResponse) with the Content-Type set to the value that corresponds to the file's extension in the mimeTypes object. If the resulting string doesn't point to an existing file or if the file's extension is not found in mimeTypes, then a 404 is served. Also, file extensions require a leading period (.) and are assumed to be lowercase. The optional maxage parameter is used to in the response's Cache-Control header. Also note that all Set-Cookie headers are removed. Here's an example of how you might use bee.staticDir:

  bee.route({
      // /pics/mofo.png serves ./content/pics/mofo.png
      // /pics/la-ghetto/oh-gee.gif serves ./content/pics/la-ghetto/oh-gee.gif
      // /pics/woo-fee.tiff serves a 404 since there's no corresponding
      // mimeType specified.
      // This helps prevent accidental exposure.
      "r`^/pics/(.*)$`": bee.staticDir(
          "./content/pics/",
          {
              ".gif": "image/gif", ".png": "image/png",
              ".jpg": "image/jpeg", ".jpeg": "image/jpeg"
          }
      ),
      // Also works with URLs with tokens
      // /static/help/faq.html serves ./static/help/faq.html
      // /static/properties.json serves a 404 since there's no corresponding
      // mimeType specified.
      "/static/`path...`": bee.staticDir(
          "./static/",
          {
              ".txt": "text/plain", ".html": "text/html",
              ".css": "text/css", ".xml": "text/xml"
          }
      ),
      // More complicated path constructs also works
      // /will-smith/img-library/headshots/sexy42.jpg
      //    serves ./user-images/will-smith/headshots/sexy42.jpg
      "/`user`/img-library/`path...`": bee.staticDir(
          "./user-images/", { ".jpg": "image/jpeg", ".jpeg": "image/jpeg" }
      )
  });

Beeline is also at least somewhat compatibile with expressjs. Here's an example:

app.use(beeline.route({
    "/": function(req, res, next) {
        fs.readFile("./templates/index.html", function(err, data) {
            if(err) { throw err; }

            res.html(data);
        });
    },
    "/`user`/static/`path...`": function(req, res, tokens, values, next) {
        /* ... code ... */
    }
}));

Note the next callback is always passed as the last parameter.

Precedence Rules

In the event that a request matches two rules, the following precedence rules are considered:

• Fully defined rules take highest precedence. In other words, "/index" has a higher precedences then "r`^/index$`" even though semantically both rules are exactly the same.
• Tokens and RegExp rules have the same precedence
• RegExp rules take higher precedence than 404
• 404 and 405 have the lowest precedences
• The 500 rules is outside the precedence rules. It can potentially be triggered at any time.
• Amoung request methods, "any" has the lowerest precdence. Also note that the "x-http-method-override" header is respected.

If the exact same rule is defined twice, then it's unspecified which request handler will be triggered.

Getting Beeline

The easiest way to get beeline is with npm:

npm install beeline

Alternatively you can clone this git repository:

git clone git://github.com/xavi-/beeline.git

Running Unit Tests

Execute the following commands to run the beeline's unit tests:

$ cd <beeline-directory>
$ cd test
$ node test.js

The last line printed to the console should be, "All done. Everything passed.", if all the tests passed successfully.

Developed by

• Xavi Ramirez

License

This project is released under The MIT License.