node-pzproxy

A pluggable HTTP/HTTPS + cache + proxy library for node.js

Installing

npm install pzproxy

Using it

"use strict";

var
    Proxy = require('pzproxy');


// Create a proxy instance
new Proxy({
    serverOpts: {
        port: 9999
    },
    cacheOpts: {
        storage: "./data"
    },
    proxyOpts: {
        target: "http://www.google.pt"
    },
    defaultTTL: 30
});

Options

• serverOpts: The options for the default HTTP server (watch the default HTTP server options below)

• server: An alternative HTTP server instance

• cacheOpts: The options for the default cache mechanism (watch the default cache mechanism options below)

• cache: An alternative cache meachnism instance

• proxyOpts: The options for the default HTTP proxy (watch the default HTTP proxy mechanism options below)

• proxy: An alternative HTTP proxy instance

• defaultTTL: The default time-to-live (in seconds) for every request (it can be personalized by changing the req.cacheTTL property)

• defaultTimeout: The default backend request timeout (in seconds). The default value is: 60

• defaultTransferTimeout: The default timeout (in ms) for transferring data from the backend. The default value is: 60000

• onRequest(): Function for handling every request. The function arguments are (request,response,callback)

• shouldCache(): Function that is called to decide whether to cache or not. The function arguments are (request,response,proxyRequest,proxyResponse). It should return a boolean value

• onFinish(): Function that is called once a request is served. The function arguments are (request,response,callback)

• logAccess(): Function that is called to log. The function arguments are (request,response,length,flags)

• debug: Activates the debug mode with a true value - default false

Default instantes

Default HTTP server (server)

• proto: Protocol ("http", "https" or "fastcgi") - defaults to "http";

• address: Address (or socket path) to bind on - defaults to "0.0.0.0";

• port: Port to bind on (or socket path with proto is "fastcgi") - defaults to 8080;

Default cache server (cache)

• storage: Directory path where to store the cached objects;

• cleanupInterval: Interval of time (in seconds) to run the cleanup mechanism, removing the expired cache object files;

Default proxy (proxy)

• target: Backend address where to send all the traffic. This parameter is optional, since you can specify a req.backendURL on the onRequest function;

## Useful request properties

By providing an onRequest function, you can fully customize your proxy rules. The first of the onRequest function arguments is request which is the node.js http.Server request with some extra properties:

• cacheKey: The cache key that will be used for storing the answer of the current request on cache (default to req.url)

• cacheTTL: The time-to-live (in seconds) on cache for the answer to the current request;

• backendURL: The URL that will be used to fetch the data to serve the current request;

• xConnectDate: Request arrival Date;

• xRequestID: Internal request ID;

• xRemoteAddr: Remote IP Address;

Useful response methods

By providing an onRequest function, you can fully customize your proxy rules. The second of the onRequest function arguments is response which is the node.js http.Server response with some extra properties:

• answer(status,headers,data): Answers the request with the supplied status, headers and data