1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
var util = require('util');
var path = require('path');
var crc = require('crc');
var FolderOutput = require('./folder');
var Promise = require('../utils/promise');
var fs = require('../utils/fs');
var imagesUtil = require('../utils/images');
var location = require('../utils/location');
var DEFAULT_ASSETS_FOLDER = 'assets';
/*
Utility mixin to inline all the assets in a book:
- Outline <svg> tags
- Download remote images
- Convert .svg images as png
*/
function AssetsInliner() {
FolderOutput.apply(this, arguments);
// Map of svg already converted
this.svgs = {};
this.inlineSvgs = {};
// Map of images already downloaded
this.downloaded = {};
}
util.inherits(AssetsInliner, FolderOutput);
// Output a SVG buffer as a file
AssetsInliner.prototype.onOutputSVG = function(page, svg) {
this.log.debug.ln('output svg from', page.path);
// Convert svg buffer to a png file
return this.convertSVGBuffer(svg)
// Return relative path from the page
.then(function(filename) {
return page.relative('/' + filename);
});
};
// Output an image as a file
AssetsInliner.prototype.onOutputImage = function(page, src) {
var that = this;
return Promise()
// Download file if external
.then(function() {
if (!location.isExternal(src)) return;
return that.downloadAsset(src)
.then(function(_asset) {
src = '/' + _asset;
});
})
.then(function() {
if (path.extname(src).toLowerCase() != '.svg') {
return src;
}
// Convert SVG to PNG
return that.convertSVGFile(that.resolveForPage(page, src));
})
// Return relative path from the page
.then(function(filename) {
return page.relative('/' + filename);
});
};
// Download an asset if not already download; returns the output file
AssetsInliner.prototype.downloadAsset = function(src) {
if (this.downloaded[src]) return Promise(this.downloaded[src]);
var that = this;
var ext = path.extname(src);
var hash = crc.crc32(src).toString(16);
// Create new file
return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + ext)
.then(function(filename) {
that.downloaded[src] = filename;
that.log.debug.ln('downloading asset', src);
return fs.download(src, that.resolve(filename))
.thenResolve(filename);
});
};
// Convert a .svg into an .png
// Return the output filename for the .png
AssetsInliner.prototype.convertSVGFile = function(src) {
if (this.svgs[src]) return Promise(this.svgs[src]);
var that = this;
var hash = crc.crc32(src).toString(16);
// Create new file
return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
.then(function(filename) {
that.svgs[src] = filename;
return imagesUtil.convertSVGToPNG(src, that.resolve(filename))
.thenResolve(filename);
});
};
// Convert an inline svg into an .png
// Return the output filename for the .png
AssetsInliner.prototype.convertSVGBuffer = function(buf) {
var that = this;
var hash = crc.crc32(buf).toString(16);
// Already converted?
if (this.inlineSvgs[hash]) return Promise(this.inlineSvgs[hash]);
return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
.then(function(filename) {
that.inlineSvgs[hash] = filename;
return imagesUtil.convertSVGBufferToPNG(buf, that.resolve(filename))
.thenResolve(filename);
});
};
module.exports = AssetsInliner;
|
