manet

Manet

There is only one true thing: instantly paint what you see. When you've got it, you've got it. When you haven't, you begin again. All the rest is humbug.

Manet is a REST API server which allows capturing screenshots of websites using various parameters. It is a good way to make sure that your websites are responsive or to make thumbnails.

Manet could use different engines to work: SlimerJS or PhantomJs.

• SlimerJS runs on top of Gecko (the browser engine of Mozilla Firefox) and SpiderMonkey (the JavaScript engine of Firefox).
• PhantomJS runs on top of WebKit and JavaScriptCore.

Project was named in honor of Édouard Manet, French painter (1832-1883). He was one of the first 19th-century artists to paint modern life, and a pivotal figure in the transition from Realism to Impressionism.

Main features

• Ready-To-Use
• Supporting SlimerJS and PhantomJS
• Configurable CLI application
• Flexible REST API
• File caching
• Various image formats
• Sandbox UI

Setup

Preset

Choose and install needed engine (PhantomJS, SlimerJS, or both of them):

SlimerJS:

• You can download SlimerJS from the official site and install manually.
• or you can use the power of NPM:

npm install -g slimerjs

Gecko, the rendering engine of Firefox, cannot render web content without a graphical window, but you can launch SlimerJS with xvfb if you are under linux or MacOSx, to have a headless SlimerJS, so it is also necessary to install Xvfb (X virtual framebuffer) for *nix or OS X systems.

For example, you can use apt-get to install xvfb on Ubuntu:

sudo apt-get install xvfb

PhantomJS

• You can download PhantomJS from the official site and install manually.
• or you can also use NPM:

npm install -g phantomjs

or (to use second version):

npm install -g phantomjs2

IMPORTANT: PhantomJS is used by default (see default.yaml file).

Installation

After preliminaries operations you can install Manet using NPM:

npm install -g manet

That is all, now you can start and use Manet server. As you can see, it is unnecessary to clone Git repository or something else.

Server launching

Server launching is a simple as possible:

manet

If everything is OK, you should see the following message:

info: Manet server started on port 8891

Server configuration

Manet server uses hierarchical configurations to cover differnet usage use-cases:

• Command-line parameters
• Environment variables
• Built-in configuration YAML file ("config/default.yaml")

Rules of overriding:

• Each configuration level could be overridden by another level.
• The most-priority parameters are command-line parameters.
• The less-priority parameters are stored in build-in configuration file.

CLI parameters

--host

Web server host (default: "0.0.0.0"). Usually, it is unnecessary to change this parameter.

--port

Web server port number. REST API and UI will be available on this port (default: "8891").

--engine

Default engine for screenshot capturing: "phantomjs" or "slimerjs" (default is "phantomjs"). Specific command will be detected by configuration file (default.yaml) using engine parameter and OS platform.

--command

Configuration file "default.yaml" supports specific commands for different platforms (ex: "linux": "xvfb-run -a slimerjs"). Needed command will be detected in runtime by platform/OS. This parameter allows to override command for executing SlimerJS. It allows using full power of SlimerJS command line options to configure proxy, SSL protocol, etc. More information could be found here: http://docs.slimerjs.org/current/configuration.html
IMPORTANT: This parameter overrides "--engine" parameter.

--storage

File storage for cache (default is global temp directory).

--cache

Lifetime for file cache in seconds. Screenshots are cached for 60 minutes by default, so that frequent requests for the same screenshot don't slow the service down. You can configure longer life for cache items or make them ethereal (use zero or negative value).

--cleanupStartup

Clean up FS storage on server startup (default is "false"). It removes all files which were stored previously.

--cleanupRuntime

Clean up FS storage at server runtime (default is "false"). It removes file with captured image after sending on client.

--compress

Additional compression for captured screenshots using Imagemin (default is "false"). File sizes are significantly reduced due to this, but it requires additional processing time. Furthermore, imagemin is an optional dependency. It will be downloaded and installed in runtime during the first request, so it will take an additional time (one time).

--silent

Run Manet server with or without logging information (default is "false").

--level

Setting the level for your logging message. Possible values: debug, info, silly, warn, error (default is "info"). If want to investigate some problem with Manet, use "debug" level: --level=debug

--cors

Enable Cross-Origin Resource Sharing (default is "false").

--ui

Enable or disable sandbox UI (default is "true").

--timeout

Number of milliseconds to wait for the program to complete before sending it "SIGTERM" (default is "60000").

--options:{option}

Default query parameters. See also "Query parameters" for more details. Example: "--options:width 101".

--whitelist

List of URL patterns that are allowed to be processed by Manet (all URLs are permitted by default).

--security:basic:username

Configure user name for Basic authentication. Basic auth will be switched on when "username" and "password" are configured.

--security:basic:password

Configure password for Basic authentication.

Configuration file

Built-in configuration could be found in manet directory. For example, on Ubuntu it is located here: "/usr/local/lib/node_modules/manet/".

Default configuration file ("default.yaml"):

host: 0.0.0.0
port: 8891
cors: false
ui: true

silent: false
level: info

engine: phantomjs
timeout: 60000
compress: false
cache: 3600
cleanupStartup: false
cleanupRuntime: false

commands:
    slimerjs:
        linux: "xvfb-run -a slimerjs"
        freebsd: "xvfb-run -a slimerjs"
        sunos: "xvfb-run -a slimerjs"
        darwin: "slimerjs"
        win32: "slimerjs.bat"
    phantomjs:
        linux: "phantomjs --ignore-ssl-errors=true --web-security=false"
        freebsd: "phantomjs --ignore-ssl-errors=true --web-security=false"
        sunos: "phantomjs --ignore-ssl-errors=true --web-security=false"
        darwin: "phantomjs --ignore-ssl-errors=true --web-security=false"
        win32: "phantomjs --ignore-ssl-errors=true --web-security=false"

whitelist:
    - "*"

security:
    basic:
#        username: admin
#        password: admin

REST API

REST API is available on "/" using:

• GET method
• POST method with Content-Type:
  • application/json
  • or application/x-www-form-urlencoded

Few rules:

• The "url" parameter must be specified.
• It is possible to send data using query parameters or HTTP Message Body.
• Query parameters will be used in priority and override others.

Available parameters

url

Website address (URL). This is the only required parameter for the HTTP request. It is unnecessary for the most cases to configure scheme. Example: "github.com".

width

This property allows to change the width of the viewport, e.g., the size of the window where the webpage is displayed (default: `1024`)

height

This property allows to change the height of the viewport. If width is defined and height is not defined, than full page will be captured.

paperFormat

Paper format for PDF export (default is `letter`). Possible values: letter, A2, A3, A4, A5.

paperOrientation

Paper orientation for PDF export (default is `portrait`). Possible values: portrait, landscape.

clipRect

This property defines the rectangular area of the web page to be rasterized. Format: "top,left,width,height", example: "20,20,640,480".

zoom

Zoom factor of the webpage display. Setting a value to this property decreases or increases the size of the web page rendering. A value between 0 and 1 decreases the size of the page, and a value higher than 1 increases its size. 1 means no zoom (normal size). (default: `1`).

quality

The compression quality. A number between 0 and 1 (default value: `1`). Quality parameter doesn't work for PNG file format.

delay

Do a pause during the given amount of time (in milliseconds) after page opening (default: `100`).

format

Indicate the file format for output image (default is `"png"`). Possible values: jpg, jpeg, png, bmp, pdf, ppm, ico.

Format	PhantomJS	SlimerJS
JPG	+	+
PNG	+	+
HTML	+	+
BMP	+	-
PDF	+	-
PPM	+	-
ICO	+	-

agent

String to define the "User-Agent" in HTTP requests. By default, it is something like:

• PhantomJS: Mozilla/5.0 (Macintosh; Intel Mac OS X) AppleWebKit/534.34 (KHTML, like Gecko) PhantomJS/1.9.0 (development) Safari/534.34
• SlimerJS: Mozilla/5.0 (X11; Linux x86_64; rv:21.0) Gecko/20100101 SlimerJS/0.7

headers

This property specifies additional HTTP request headers that will be sent to the server for every request issued (for pages and resources). Format: "key1=value1;key2=value2;..." Headers names and values get encoded in US-ASCII before being sent. Please note that setting the 'User-Agent' will overwrite the value set via "agent" parameter.

user

User name to give to HTTP Basic authentication.

password

Password to give to HTTP Basic authentication.

js

false to deactivate javascript in web pages (default is `true`).

images

false to deactivate the loading of images (default is `true`).

force

Use the force reloading of web page without using cache (default is `false`).

selector

Wait for the DOM element, that matches the CSS selector, to be available before taking the screenshot.

selectorCrop

Crop page by offset coordinates of selected(by CSS selector) element. (default is `false`). Leave `height` option empty, for this is working correctly.

selectorCropPadding

Add padding to 'selectorCrop'. You can use negative values. (default is 0).

callback

Return an empty response immediately (HTTP 200 OK), then send a POST request to the callback URL when the screenshot is ready (with image in the body).

engine

Override default engine parameter. Possible values: `phantomjs`, `slimerjs`.

cookies

Configure cookies that will be contained in request. HTTP message body is the easiest way for sending cookies to Manet (ex: using JSON format).

Query examples

For a quick test with the command line (using curl), type:

curl http://localhost:8891/?url=github.com > github.png
curl -H "Content-Type: application/json" -d '{"url":"github.com"}' http://localhost:8891/ > github.png
curl -H "Content-Type: application/x-www-form-urlencoded" -d 'url=github.com' http://localhost:8891/ > github.png

or (using wget)

wget http://localhost:8891/?url=github.com -O github.png

Here are some query examples that could be executed by any REST API client:

# Take a screenshot of the github.com.
GET /?url=github.com

# Custom viewport size. Return a 800x600 PNG screenshot of the github.com homepage.
GET /?url=github.com&width=800&height=600

# Clipping Rectangle. Return a screenshot clipped at [top=20, left=30, width=90, height=80]
GET /?url=github.com&clipRect=20%2C30%2C90%2C80

# Zoom rendered page in 2 times.
GET /?url=github.com&zoom=2

# Specify image output format.
GET /?url=github.com&format=jpeg

# Disable JavaScript. Return a screenshot with no JavaScript executed.
GET /?url=github.com&js=false

# Disable images. Return a screenshot without images.
GET /?url=github.com&images=false

# Custom User Agent.
GET /?url=github.com&agent=Mozilla%2F5.0+(X11%3B+Linux+x86_64)+AppleWebKit%2F537.36+(KHTML%2C+like+Gecko)+Chrome%2F34.0.1847.132+Safari%2F537.36

# HTTP Basic Authentication. Return a screenshot of a website requiring basic authentication.
GET /?url=mysite.com&user=john&password=smith

# Screenshot delay. Return a screenshot of the github.com homepage 1 second after it's loaded.
GET /?url=github.com&delay=1000

# Force page reloading. Return a screenshot without using file cache.
GET /?url=github.com&force=true

# Wait for a div element with a class name "header" to be available.
GET /?url=github.com&selector=div.header

# Specify custom HTTP headers.
GET /?url=google.com&headers=User-Agent=Firefox;Accept-Charset=utf-8

# Asynchronous call.
GET /?url=github.com&callback=http://localhost:8891

Sandbox UI

Sandbox UI is available on "/" by direct GET request without "url" query parameter. It is a simple playground to build HTTP requests and try them.

Demo instance is available on Heroku: https://manet.herokuapp.com

You can also use "Deploy to Heroku" button to create your own Manet instance on Heroku without leaving the web browser, and with little configuration.

Development

• To install project dependencies:

npm install

• To run jshint checks:

npm run lint

• To run Mocha unit tests:

# using NPM:
npm test
# using mocha and watcher:
mocha --watch -R spec

• To run Manet server:

./bin/manet

Alternative clients

Ruby:

• manet_client is a simple Ruby client library for Manet.

Deployment options

Docker

Docker is an open platform to build, ship, and run distributed applications, whether on laptops, data center VMs, or the cloud.

Manet has some already known Dockerfiles:

• Pietro Delsante provides the first manet-dockerfile to run Manet inside a Docker container.
• Kris Carle provides fork of previous project with WebGL support for SlimerJS.
• Walter Franchetti provides docker-Manet with PhantomJS and libfreetype6.
• Olivier Balais provides docker-manet with extended charactersets such as Japanese and Chinese.

Heroku

First of all read https://devcenter.heroku.com/articles/deploying-nodejs (section "Deploy your application to Heroku"). You need to create Heroku instance with as described in this documentation.

Procfile file for PhantomJS is already existed in root of the project. This file describes Heroku how to start Manet.

SlimerJS does not work on Heroku, because it has not got a headless mode and it is quite complicated to install xvfb on this platform (but you can try your luck).

Thanks to

• SlimerJS author Laurent Jouanneau and SlimerJS community.
• PhantomJS author Ariya Hidayat and PhantomJS community.
• Pietro Delsante, Kris Carle, Walter Franchetti, and Olivier Balais for running project inside a Docker container.
• Felipe JAPM for Ruby client.
• All contributors for their help and pull requests.

Self portrait

One picture more than a thousand words:

License

The MIT License (MIT)

Copyright (c) 2014 Vladislav Bauer (see LICENSE).