mirror of
https://github.com/sbrl/powahroot.git
synced 2024-11-22 14:32:59 +00:00
218 lines
8.7 KiB
JavaScript
218 lines
8.7 KiB
JavaScript
"use strict";
|
|
|
|
import RouterContext from './RouterContext.mjs';
|
|
import pathspec_to_regex from '../Shared/Pathspec.mjs';
|
|
|
|
/**
|
|
* A standalone HTTP router that's based on the principle of middleware.
|
|
* Based on rill (see the npm package bearing the name), but stripped down and
|
|
* simplified.
|
|
* @param {Boolean} verbose Whether to be verbose and log a bunch of things to the console. Useful for debugging.
|
|
*/
|
|
class ServerRouter
|
|
{
|
|
constructor(verbose = false) {
|
|
/**
|
|
* The actions to run in turn.
|
|
* @private
|
|
* @type {Array<Function>}
|
|
*/
|
|
this.actions = [];
|
|
/** Whether to activate verbose mode. Useful for debugging the router. */
|
|
this.verbose = verbose;
|
|
|
|
this.default_action = async (ctx) => {
|
|
let message = `No route was found for '${ctx.request.url}'.`;
|
|
if(this.verbose) {
|
|
message += `\n\nRegistered Actions:\n`;
|
|
for(let action of this.actions) {
|
|
message += ` - ${action.toString()}\n`;
|
|
}
|
|
}
|
|
ctx.send.plain(404, message);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Shortcut function for attaching an action to any request method.
|
|
* Full function: on
|
|
* @param {string|RegExp} pathspec The pathspec that the route should match against.
|
|
* @param {Function} action The function to execute when this route is matches.gets passed 2 parameters: context (or type RequestContext) and next (a function). context contains the request / response objects, and next() should be called if the action is middleware.
|
|
*/
|
|
any(pathspec, action) { this.on("*", pathspec, action); }
|
|
/**
|
|
* Shortcut function for attaching an action to head requests. Full function: on
|
|
* @param {string|RegExp} pathspec The pathspec that the route should match against.
|
|
* @param {Fuction} action The function to execute.
|
|
* @example
|
|
* router.head("/location/:name/status", (context, _next) => {
|
|
* context.send.plain(200, `Coming in from ${context.params.type} - status ok!`);
|
|
* });
|
|
*/
|
|
head(pathspec, action) { this.on(["head"], pathspec, action); }
|
|
/**
|
|
* Shortcut function for attaching an action to get requests. Full function: on
|
|
* @param {string|RegExp} pathspec The pathspec that the route should match against.
|
|
* @param {Fuction} action The function to execute.
|
|
* @example
|
|
* router.get("/tree/:type", (context, _next) => {
|
|
* context.send.plain(200, `Hello, I am a ${context.params.type}`);
|
|
* });
|
|
*/
|
|
get(pathspec, action) { this.on(["get"], pathspec, action); }
|
|
/**
|
|
* Shortcut function for attaching an action to post requests. Full function: on
|
|
* @param {string|RegExp} pathspec The pathspec that the route should match against.
|
|
* @param {Fuction} action The function to execute.
|
|
* @example
|
|
* router.post("/loaction/:name/update", (context, _next) => {
|
|
* context.send.plain(501, `Hello from ${context.params.name}! I don't yet support updating my firmware.\nYou asked me to update to version ${context.post_data.version}.`);
|
|
* // See https://github.com/sbrl/powahroot/blob/master/examples/parse_post_data.mjs for an example of parsing post data with middleware that works with the above (context.post_data is not created automatically by powahroot)
|
|
* });
|
|
*/
|
|
post(pathspec, action) { this.on(["post"], pathspec, action); }
|
|
/**
|
|
* Shortcut function for attaching an action to put requests. Full function: on
|
|
* @param {string|RegExp} pathspec The pathspec that the route should match against.
|
|
* @param {Fuction} action The function to execute.
|
|
*/
|
|
put(pathspec, action) { this.on(["put"], pathspec, action); }
|
|
/**
|
|
* Shortcut function for attaching an action to delete requests. Full function: on
|
|
* @param {string|RegExp} pathspec The pathspec that the route should match against.
|
|
* @param {Fuction} action The function to execute.
|
|
*/
|
|
delete(pathspec, action) { this.on(["delete"], pathspec, action); }
|
|
/**
|
|
* Shortcut function for attaching an action to options requests. Full function: on
|
|
* @param {string|RegExp} pathspec The pathspec that the route should match against.
|
|
* @param {Fuction} action The function to execute.
|
|
* @example
|
|
* router.options("/location/:name/status", (context, _next) => {
|
|
* context.send.plain(200, `I support these actions:\n - GET: Get my status\n - POST: Set my status\n - OPTIONS: Show this message`);;
|
|
* });
|
|
*/
|
|
options(pathspec, action) { this.on(["options"], pathspec, action); }
|
|
|
|
/**
|
|
* Execute the specified action for requests matching the given parameters.
|
|
* TODO: Consider merging with on_all and refactoring to take an object literal which we can destructure instead
|
|
* @param {array} methods The HTTP methods to run the action for. Include '*' to specify all methods.
|
|
* @param {string|regex} pathspec The specification of the paths that this action should match against. May be a regular expression.
|
|
* @param {Function} action The action to execute. Will be passed the parameters `context` (RouterContext) and `next` (Function).
|
|
* @example
|
|
* router.on(["get"], "/garden/:vegetable", (context) => {
|
|
* context.send(201, `Planted ${context.params.vegetable}`);
|
|
* });
|
|
*/
|
|
on(methods, pathspec, action) {
|
|
let regex_info = pathspec instanceof RegExp ? {regex: pathspec, tokens: [] } : pathspec_to_regex(pathspec);
|
|
|
|
// next must be a generator that returns each action in turn
|
|
this.actions.push(async (context, next) => {
|
|
const matches = context.url.pathname.match(regex_info.regex);
|
|
|
|
if(this.verbose) console.error(`[router/verbose] [${methods.join(", ")} -> ${pathspec} ] Matches: `, matches);
|
|
|
|
if((methods.indexOf(context.request.method.toLowerCase()) > -1 || methods.indexOf("*") > -1) && matches) {
|
|
if(this.verbose) console.error(`[router/verbose] Match found! Executing action.`);
|
|
for(let i = 1; i < matches.length; i++) { // Skip the top-level group
|
|
context.params[regex_info.tokens[i-1]] = matches[i];
|
|
}
|
|
await action(context, next);
|
|
}
|
|
else {
|
|
if(this.verbose) console.error(`[router/verbose] Nope, didn't match. Moving on`);
|
|
await next();
|
|
}
|
|
});
|
|
}
|
|
|
|
/**
|
|
* Adds a route that matches against every request.
|
|
* Usually useful for middleware (e.g. error handlers, request loggers, authentication handlers, etc.).
|
|
* @param {Function} action The function to execute.
|
|
* @example
|
|
* router.on_all((context) => {
|
|
* context.send.plain(200, "Hello, world!");
|
|
* });
|
|
*/
|
|
on_all(action) {
|
|
this.actions.push(action);
|
|
}
|
|
|
|
/**
|
|
* Runs the specified action for requests if the provided testing function
|
|
* returns true.
|
|
* @param {Function} test The testing function. Will be passed the context as it's only parameter.
|
|
* @param {Function} action The action to run if the test returns true.
|
|
*/
|
|
onif(test, action) {
|
|
this.actions.push(async (context, next) => {
|
|
let test_result = test(context);
|
|
if(this.verbose) console.error("[router/verbose] Test action result: ", test_result);
|
|
if(test_result)
|
|
await action(context, next);
|
|
else
|
|
await next(context);
|
|
})
|
|
}
|
|
|
|
/**
|
|
* Handles the specified request.
|
|
* Don't forget to await the Promise!
|
|
* @param {http.ClientRequest} request The request to handle.
|
|
* @param {http.ServerResponse} response The response object to use to send the response.
|
|
* @return {Promise} A Promise that resolves when handling is complete.
|
|
* @example
|
|
* const server = http.createServer(async (request, response) => {
|
|
* await router.handle(request, response);
|
|
* });
|
|
* server.listen(3500, "127.0.0.1", () => console.log("Listening on http://127.0.0.1:3500/"));
|
|
*/
|
|
async handle(request, response) {
|
|
let context = new RouterContext(request, response),
|
|
iterator = this.iterate();
|
|
|
|
// Begin the middleware execution
|
|
this.gen_next(iterator, context)();
|
|
}
|
|
|
|
/**
|
|
* Returns an anonymous function that, when called, will execute the next
|
|
* item of middleware.
|
|
* It achieves this via a combination of a generator, anonymous function
|
|
* scope abuse, being recursive, and magic.
|
|
* You shouldn't need to call this directly.
|
|
* @private
|
|
* @param {Generator} iterator The generator that emits the middleware.
|
|
* @param {Object} context The context of the request.
|
|
* @return {Function} A magic next function.
|
|
*/
|
|
gen_next(iterator, context) {
|
|
let next_raw = iterator.next();
|
|
// Return the default action if we've reached the end of the line
|
|
if(next_raw.done)
|
|
return async () => {
|
|
this.default_action(context);
|
|
};
|
|
|
|
return (async () => {
|
|
if(this.verbose) console.error(`[router/verbose] Executing ${next_raw.value}`);
|
|
await next_raw.value(context, this.gen_next(iterator, context));
|
|
}).bind(this); // Don't forget to bind each successive function to this context
|
|
}
|
|
|
|
/**
|
|
* Iterates over all the generated middleware.
|
|
* @return {Generator} A generator that returns each successive piece of middleware in turn.
|
|
* @generator
|
|
*/
|
|
*iterate() {
|
|
for(let action of this.actions) {
|
|
yield action;
|
|
}
|
|
}
|
|
}
|
|
|
|
export default ServerRouter;
|