Ghost/core/server/utils/image-size-from-url.js
Aileen Nowak a5c29dfc34 [FEATURE] AMP (#7229)
closes #6588, #7095

* `ImageObject` with image dimensions (#7152, #7151, #7153)
- Returns meta data as promise
    - returns a new Promise from meta data
    - uses `Promise.props()` to resolve `getClient()` and `getMetaData()`

- Adds 'image-size' util
The util returns an object like this
```
{
    height: 50,
    url: 'http://myblog.com/images/cat.jpg',
    width: 50
};
```
if the dimensions can be fetched and rejects with error, if not.
In case we get a locally stored image or a not complete url (like `//www.gravatar.com/andsoon`), we add the protocol to the incomplete one and use `urlFor()` to get the absolute URL. If the request fails or `image-size` is not able to read the file, we reject with error.
- adds 'image-size' module to dependencies
- adds `getImageSizeFromUrl` function that returns image dimensions

- In preparation of AMP support and to improve our schema.org JSON-LD and structured data, I made the following changes:
    - Changes the following properties to be `Objects`, which have a `url` property by default and a `dimensions` property, if `width` and `height` are available:
        - `metaData.coverImage`
        - `metaData.authorImage`
        - `metaData.blog.logo`
    - Checks cache by calling `getCachedImageSizeFromUrl`. If image dimensions were fetched already, returns them from cache instead of fetching them again.
    - If we have image dimensions on hand, the output in our JSON-LD changes from normal urls to be full `ImageObjects`. Applies to all images and logos.
    - Special case for `publisher.logo` as it has size restrictions: if the image doesn't fulfil the restrictions (<=600 width and <=60 height), we simply output the url instead, so like before.
    - Adds new property for schema.org JSON-LD: `mainEntityOfPage` as an Object.
    - Adds additional Open Graph data (if we have the image size): `og:image:width` and `og:image:height`
    - Adds/updates tests

* AMP router and controller (#7171, #7157)
Implements AMP in `/apps/`:
- renders `amp.hbs` if route is `/:slug/amp/`
- updates `setResponseContext` to set context to `['amp', 'post']` for a amp post and `['amp', 'page']` for a page, but will not render amp template for a page
- updates `context_spec`
- registers 'amp' as new internal app
- adds the `amp.hbs` template to `core/server/apps/amp` which will be the default template for AMP posts.
- adds `isAmpURL` to `post-lookup`

* 🎨 Use `context` in meta as array (#7205)
Instead of reading the first value of the context array, we're checking if it includes certain context values.
This is a preparation change for AMP, where the context will be delivered as `['amp', 'post']`.

*  AMP helpers (#7174, #7216, #7215, #7223)
- Adds AMP helpers `{{amp_content}}`, `{{amp_component}}` and  `{{amp_ghost_head}}` to support AMP:
- `{{amp_content}}`:
    - Adds `Amperize` as dependency
    - AMP app uses new helper `{{amp_content}}` to render AMP HTML
    - `Amperize` transforms regular HTML into AMP HTML
    - Adds test for `{{amp_content}}` helper
    - Adds 'Sanitize-HTML` as dependendy
    - After the HTML get 'amperized' we still might have some HTML tags, which are prohibited in AMP HTML, so we use `sanitize-html` to remove those. With every update, `Amperize` gets and it is able to transform more HTML tags, they valid AMP HTML tags (e. g. `video` and `amp-video`) and will therefore not be removed.
- `{{amp_ghost_head}}`:
    - registers `{{amp_ghost_head}}` helper, but uses `{{ghost_head}}` code
    - uses `{{amp_ghost_head}}` in `amp.hbs` instead of `{{ghost_head}}`
- `{{ghost_head}}`:
    - Render `amphtml` link in metadata for post, which links to the amp post (`getAmpUrl`)
    - Updates all test in metadata to support `amp` context
    - Changes context conditionals to work with full array instead of first array value
    - Adds conditionals, so no additional javascript gets rendered in `{{ghost_head}}`
    - Removes trailing `/amp/` in URLs, so only `amphtml` link on regular post renders it
    - Adds a conditional, so no code injection will be included, for an `amp` context.
- `{{amp_components}}`:
    - AMP app uses new helper `{{amp_components}}` to render necessary script tags for AMP extended components as `amp-iframe`, `amp-anime` and `amp-form`
    - Adds test for `{{amp_components}}`
2016-08-22 18:49:27 +02:00

101 lines
3.5 KiB
JavaScript

// Supported formats of https://github.com/image-size/image-size:
// BMP, GIF, JPEG, PNG, PSD, TIFF, WebP, SVG
// ***
// Takes the url of the image and an optional timeout
// getImageSizeFromUrl returns an Object like this
// {
// height: 50,
// url: 'http://myblog.com/images/cat.jpg',
// width: 50
// };
// if the dimensions can be fetched and rejects with error, if not.
// ***
// In case we get a locally stored image or a not complete url (like //www.gravatar.com/andsoon),
// we add the protocol to the incomplete one and use urlFor() to get the absolute URL.
// If the request fails or image-size is not able to read the file, we reject with error.
var sizeOf = require('image-size'),
url = require('url'),
Promise = require('bluebird'),
http = require('http'),
https = require('https'),
config = require('../config'),
dimensions,
request,
requestHandler;
/**
* @description read image dimensions from URL
* @param {String} imagePath
* @param {Number} timeout (optional)
* @returns {Promise<Object>} imageObject or error
*/
module.exports.getImageSizeFromUrl = function getImageSizeFromUrl(imagePath, timeout) {
return new Promise(function imageSizeRequest(resolve, reject) {
var imageObject = {},
options;
imageObject.url = imagePath;
// check if we got an url without any protocol
if (imagePath.indexOf('http') === -1) {
// our gravatar urls start with '//' in that case add 'http:'
if (imagePath.indexOf('//') === 0) {
// it's a gravatar url
imagePath = 'http:' + imagePath;
} else {
// get absolute url for image
imagePath = config.urlFor('image', {image: imagePath}, true);
}
}
options = url.parse(imagePath);
requestHandler = imagePath.indexOf('https') === 0 ? https : http;
options.headers = {'User-Agent': 'Mozilla/5.0'};
request = requestHandler.get(options, function (res) {
var chunks = [];
res.on('data', function (chunk) {
chunks.push(chunk);
});
res.on('end', function () {
if (res.statusCode === 200) {
try {
dimensions = sizeOf(Buffer.concat(chunks));
imageObject.width = dimensions.width;
imageObject.height = dimensions.height;
return resolve(imageObject);
} catch (err) {
// @ToDo: add real error handling here as soon as we have error logging
return reject(err);
}
} else {
// @ToDo: add real error handling here as soon as we have error logging
var err = new Error();
err.message = imagePath;
err.statusCode = res.statusCode;
return reject(err);
}
});
}).on('socket', function (socket) {
// don't set timeout if no timeout give as argument
if (timeout) {
socket.setTimeout(timeout);
socket.on('timeout', function () {
request.abort();
});
}
}).on('error', function (err) {
// @ToDo: add real error handling here as soon as we have error logging
return reject(err);
});
});
};