oh-see 
======

So that you can see how OC components look in production before publishing them to production.

Oh-see is a wrapper for mirror-mirror which is a wrapper for Nightmare.js. Oh-see is been built for:

* Opening a matrix of urls and viewports with Chrome
* Optionally specify a set of operations to perform
* Take a screenshot
* Replace a component's baseUrl and re-render it
* Optionally specify another set of operations to perform
* Take another screenshot
* Compare the screenshots and save a diff file with the highlighted differences

Most important features:
* Crazy quick compare to Selenium with Phantom
* Able to hide/show Browser
* Works with any OS
* Able to use DevTools and do debugging with Chrome

Requirements:

* Node version: min: 6
* container needs to be present in rendered components to make oh-see work.

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``js
npm install oh-see
`

$3

`js
const OhSee = require('oh-see');

const oh = OhSee({
// Nightmare.js options
openDevTools: true,
show: false
});

oh.setup({
concurrency: 5,
timeout: 20000,
debug: true,
componentName: 'a-component',

urls: {
com_home: 'http://www.mywebsite.com',
com_search: 'http://www.mywebsite.com/?s=something',
com_product: 'https://www.mywebsite.com/item'
},

transformation: {
type: 'replaceBaseUrl',
newUrl: 'http://localhost:3030/',
oldUrl: 'https://oc-registry.mywebsite.com/'
},

screenshotsPath: './screenshots'
});

oh.run((err, result) => {
console.log(arguments);
process.exit(0);
});
`

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1. Set up an instance
2. Configure the runner
* action examples
* transformation types
3. Start the runner

$3

var ohSee = new OhSee([NighmareOptions]);

Look at Nighmare.js options.

$3

ohSee.setup(ohSeeOptions);

This is an object with the following structure:

|name|type|mandatory|description|
|----|----|---------|-----------|
|componentName|string|yes|The component name|
|concurrency|number|no|Default 3, is the concurrency of tests|
|cookies|object|no|Allows to specify cookies to be used for each request|
|debug|boolean|no|When true, shows stuff in the console|
|headers|object|no|Allows to specify headers to be used for each request|
|preRendering|array of functions|no|An array of nightmareJs actions to perform before the first screenshots. Look at the example below|
|postRendering|array of functions|no|An array of nightmareJs actions to perform after the transformation and before the second screenshots. Look at the example below|
|retries|number|no|Default 3, number of retries after a failing session|
|screenshotsPath|string|yes|The path where to save the screenshots|
|timeout|number|no|Default 20000, when the session is going to be restarted|
|transformation|object|yes|The transformation to apply to the component. Look at the Transformation types below|
|tryAppendLang|boolean|no|Default false, when true appends to the component's href the __ocAcceptLanguage parameter, inheriting the value from html DOM element's lang attribute. This is required when re-rendering a server-side rendered component that depends on Accept-Language attribute for being rendered in the correct language|
|urls|object|yes|The urls to test. Key is used to generate screenshots file name so keep it simple and without spaces and stuff|
|viewports|array of arrays|no|Default [[800, 600]], the viewports for executing the tests|

#### Nightmare actions example

This example shows how to make a screenshot with a menu opened, assuming the transformation replaces the menu and then needs to run another javascript initialisation and then wait to complete before performing the same action again.

`js
ohSee.setup({
...
preRender: [
(nightmare) => nightmare.evaluate(() => $('#navbar-button').click()
],
postRender: [
(nightmare) => nightmare.evaluate(() => {
window.menusReady = false;
window.menus.initialise(() => window.menusReady = true);
}),

(nightmare) => nightmare.wait(() => window.menusReady === true),

(nightmare) => nightmare.evaluate(() => $('#navbar-button').click())
]
});
`

#### Transformation types

##### Base url replacement

Replaces the components' base url to another one. Useful for comparing a local one with the production one.

`js
const transformation = {
type: 'replaceBaseUrl',
oldUrl: 'https://my-registry.my-company.com',
newUrl: 'http://localhost:3000/'
};
...
`

$3

ohSee.run(callback);`

Where callback is going to have an error and/or a response with the results. If any of the requests fails, the callback will include both an error + the response with succeeding screenshot links.

Contributing

Yes please. Open an issue first.

$3

MIT