https://github.com/pvande/polliwog
Making HTTP polling less annoying for everyone.
https://github.com/pvande/polliwog
http nodejs polling
Last synced: about 2 months ago
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Making HTTP polling less annoying for everyone.
- Host: GitHub
- URL: https://github.com/pvande/polliwog
- Owner: pvande
- Created: 2017-07-04T06:28:40.000Z (almost 8 years ago)
- Default Branch: master
- Last Pushed: 2017-07-11T08:16:45.000Z (almost 8 years ago)
- Last Synced: 2025-03-13T11:05:08.858Z (3 months ago)
- Topics: http, nodejs, polling
- Language: JavaScript
- Homepage: https://www.npmjs.com/package/polliwog
- Size: 90.8 KB
- Stars: 0
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
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README
# Polliwog
Sometimes it's unavoidable. The only way to get updates from that web service
you love is to nag at it, endlessly repeating the same HTTP request like a child
who's grown tired of the car ride. **Polliwog manages the details so that you
can focus on the data.**
## Features
* Transforms a URL into an EventEmitter **stream of data events**.
* **Cache-hint awareness** means fewer unnecessary HTTP requests by default.
* **Response de-duplication** keeps your application from re-processing the same
data over and over again.
## Getting Started
There's no better way to explain Polliwog than with an example.
``` javascript
const url = 'http://date.jsontest.com'
const options = { json: true }
const p = new Polliwog(url, options)
p.on('response', console.log)
p.start()
```
## Configuration
The Polliwog constructor takes two arguments, he HTTP or HTTPS URL to poll, and
an optional hash of configuration options.
The following configuration options are supported.
#### `interval` (default: `500`)
Specifies the polling interval, in milliseconds.
#### `json` (default: `false`)
When `true`, response bodies will be parsed as JSON.
#### `emitUnchanged` (default: `false`)
When `true`, events will be fired following every request (rather than when data
has changed).
#### `skipCache` (default: `false`)
When `true`, locally cached data will always be considered expired. *Note that
on its own, this will still result in conditional requests based on the `Etag`
and `Last-Modified` headers being made.*
#### `skipEtag` (default: `false`)
When `true`, Etags will not be considered when testing cache validity.
#### `skipLastModified` (default: `false`)
When `true`, the Last-Modified date will not be considered when testing cache
validity.
## Events
#### `'response'` => `(code, headers, body)`
Produces a stream of HTTP responses, regardless of HTTP status code.
#### `success` => `(body)`
Produces a stream of successful HTTP responses (`2xx`).
#### `failure` => `(body)`
Produces a stream of unsuccessful HTTP responses (`4xx` and `5xx`).
#### `error` => `(err)`
Produces a stream of exceptions, from networking failures to JSON parsing errors.
## API
#### `new Polliwog(url, options)`
Constructs a new poller for the specified URL. See
[Configuration](#configuration) for a list of the supported options.
#### `on(event, callback)`
#### `addListener(event, callback)`
Registers a new callback for the named event. See [Events](#events) for a list
of the supported events.
#### `removeListener(event, callback)`
Unregisters a callback from the named event.
#### `start()`
Begins polling the URL for data and firing the appropriate events.
#### `stop()`
Terminates the current polling cycle and aborts any further data processing.
Events for any outstanding requests may still be fired after this method is
called.