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Make PDFDocument a node stream

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This commit is contained in:
Devon Govett 2014-03-23 17:11:48 -07:00
parent 1305a9592a
commit f8a40dba76
13 changed files with 335 additions and 332 deletions
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194
lib/document.coffee
View File

@ -3,14 +3,16 @@ PDFDocument - represents an entire PDF document
By Devon Govett
###
stream = require 'stream'
fs = require 'fs'
PDFObjectStore = require './store'
PDFObject = require './object'
PDFReference = require './reference'
PDFPage = require './page'
class PDFDocument
class PDFDocument extends stream.Readable
constructor: (@options = {}) ->
super
# PDF version
@version = 1.3
@ -18,10 +20,17 @@ class PDFDocument
@compress = yes
# The PDF object store
@store = new PDFObjectStore
# A list of pages in this document
@pages = []
@_objects = []
@_waiting = 0
@_ended = false
@_offset = 0
@_root = @ref
Type: 'Catalog'
Pages: @ref
Type: 'Pages'
Count: 0
Kids: []
# The current page
@page = null
@ -33,16 +42,22 @@ class PDFDocument
@initText()
@initImages()
# Create the metadata
@_info = @ref
# Initialize the metadata
@info =
Producer: 'PDFKit'
Creator: 'PDFKit'
CreationDate: new Date()
@info = @_info.data
if @options.info
@info[key] = val for key, val of @options.info
delete @options.info
for key, val of @options.info
@info[key] = val
# Write the header
# PDF version
@_write "%PDF-#{@version}"
# 4 binary chars, as recommended by the spec
@_write "%\xFF\xFF\xFF\xFF"
# Add the first page
@addPage()
@ -61,12 +76,16 @@ class PDFDocument
mixin 'annotations'
addPage: (options = @options) ->
# end the current page if needed
@page?.end()
# create a page object
@page = new PDFPage(this, options)
# add the page to the object store
@store.addPage @page
@pages.push @page
pages = @_root.data.Pages.data
pages.Kids.push @page.dictionary
pages.Count++
# reset x and y coordinates
@x = @page.margins.left
@ -80,90 +99,97 @@ class PDFDocument
return this
ref: (data) ->
@store.ref(data)
ref = new PDFReference(this, @_objects.length + 1, data)
@_objects.push ref
@_waiting++
return ref
addContent: (str) ->
@page.content.add str
return this # make chaining possible
_read: ->
# do nothing, but this method is required by node
_write: (data) ->
unless Buffer.isBuffer(data)
data = new Buffer(data + '\n', 'binary')
@push data
@_offset += data.length
addContent: (data) ->
@page.write data
return this
_refEnd: ->
if --@_waiting is 0 and @_ended
@_finalize()
@_ended = false
write: (filename, fn) ->
@output (out) ->
fs.writeFile filename, out, 'binary', fn
# print a deprecation warning with a stacktrace
err = new Error '
PDFDocument#write is deprecated, and will be removed in a future version of PDFKit.
Please pipe the document into a Node stream.
'
console.warn err.stack
@pipe fs.createWriteStream(filename)
@end()
@once 'end', fn
output: (fn) ->
@finalize =>
out = []
@generateHeader out
@generateBody out, =>
@generateXRef out
@generateTrailer out
# more difficult to support this. It would involve concatenating all the buffers together
throw new Error '
PDFDocument#output is deprecated, and has been removed from PDFKit.
Please pipe the document into a Node stream.
'
ret = []
for k in out
ret.push(k + '\n')
fn new Buffer(ret.join(''),'binary')
end: ->
@page.end()
finalize: (fn) ->
# convert strings in the info dictionary to literals
for key, val of @info when typeof val is 'string'
@info[key] = PDFObject.s val, true
@_info = @ref()
for key, val of @info
if typeof val is 'string'
val = PDFObject.s val, true
@_info.data[key] = val
@_info.end()
# embed the subsetted fonts
@embedFonts =>
# embed the images
@embedImages =>
done = 0
cb = => fn() if ++done is @pages.length
# finalize each page
for page in @pages
page.finalize(cb)
for name, font of @_fontFamilies
font.embed()
@_root.end()
@_root.data.Pages.end()
generateHeader: (out) ->
# PDF version
out.push "%PDF-#{@version}"
# 4 binary chars, as recommended by the spec
out.push "%\xFF\xFF\xFF\xFF\n"
return out
if @_waiting is 0
@_finalize()
else
@_ended = true
generateBody: (out, fn) ->
offset = out.join('\n').length + 1
_finalize: (fn) ->
# generate xref
xRefOffset = @_offset
@_write "xref"
@_write "0 #{@_objects.length + 1}"
@_write "0000000000 65535 f "
refs = (ref for id, ref of @store.objects)
do proceed = =>
if ref = refs.shift()
ref.object @compress, (object) ->
ref.offset = offset
out.push object
offset += object.length + 1 # plus one for newline
proceed()
else
@xref_offset = offset
fn()
generateXRef: (out) ->
len = @store.length + 1
out.push "xref"
out.push "0 #{len}"
out.push "0000000000 65535 f "
for id, ref of @store.objects
for ref in @_objects
offset = ('0000000000' + ref.offset).slice(-10)
out.push offset + ' 00000 n '
generateTrailer: (out) ->
trailer = PDFObject.convert
Size: @store.length + 1
Root: @store.root
@_write offset + ' 00000 n '
# trailer
@_write 'trailer'
@_write PDFObject.convert
Size: @_objects.length
Root: @_root
Info: @_info
@_write 'startxref'
@_write "#{xRefOffset}"
@_write '%%EOF'
out.push 'trailer'
out.push trailer
out.push 'startxref'
out.push @xref_offset
out.push '%%EOF'
# end the stream
@push null
toString: ->
"[object PDFDocument]"

107
lib/font.coffee
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@ -10,10 +10,12 @@ zlib = require 'zlib'
class PDFFont
constructor: (@document, @filename, @family, @id) ->
@ref = @document.ref()
if @filename in @_standardFonts
@isAFM = true
@font = AFMFont.open __dirname + "/font/data/#{@filename}.afm"
@registerStandard()
@registerAFM()
else if /\.(ttf|ttc)$/i.test @filename
@font = TTFFont.open @filename, @family
@ -31,9 +33,11 @@ class PDFFont
use: (characters) ->
@subset?.use characters
embed: (fn) ->
return fn() if @isAFM
@embedTTF fn
embed: ->
if @isAFM
@embedAFM()
else
@embedTTF()
encode: (text) ->
if @isAFM
@ -74,59 +78,49 @@ class PDFFont
@flags |= 1 << 5 # assume the font is nonsymbolic...
throw new Error 'No unicode cmap for font' if not @font.cmap.unicode
embedTTF: ->
data = @subset.encode()
fontfile = @document.ref()
fontfile.write data
# Create a placeholder reference to be filled in embedTTF.
@ref = @document.ref
fontfile.data.Length1 = fontfile.uncompressedLength
fontfile.end()
descriptor = @document.ref
Type: 'FontDescriptor'
FontName: @subset.postscriptName
FontFile2: fontfile
FontBBox: @bbox
Flags: @flags
StemV: @stemV
ItalicAngle: @italicAngle
Ascent: @ascender
Descent: @decender
CapHeight: @capHeight
XHeight: @xHeight
descriptor.end()
firstChar = +Object.keys(@subset.cmap)[0]
charWidths = for code, glyph of @subset.cmap
Math.round @font.widthOfGlyph(glyph)
cmap = @document.ref()
cmap.end toUnicodeCmap(@subset.subset)
@ref.data =
Type: 'Font'
BaseFont: @subset.postscriptName
Subtype: 'TrueType'
embedTTF: (fn) ->
data = @subset.encode()
zlib.deflate data, (err, compressedData) =>
throw err if err
FontDescriptor: descriptor
FirstChar: firstChar
LastChar: firstChar + charWidths.length - 1
Widths: charWidths
Encoding: 'MacRomanEncoding'
ToUnicode: cmap
@fontfile = @document.ref
Length: compressedData.length
Length1: data.length
Filter: 'FlateDecode'
@fontfile.add compressedData
@descriptor = @document.ref
Type: 'FontDescriptor'
FontName: @subset.postscriptName
FontFile2: @fontfile
FontBBox: @bbox
Flags: @flags
StemV: @stemV
ItalicAngle: @italicAngle
Ascent: @ascender
Descent: @decender
CapHeight: @capHeight
XHeight: @xHeight
firstChar = +Object.keys(@subset.cmap)[0]
charWidths = for code, glyph of @subset.cmap
Math.round @font.widthOfGlyph(glyph)
cmap = @document.ref()
cmap.add toUnicodeCmap(@subset.subset)
ref =
Type: 'Font'
BaseFont: @subset.postscriptName
Subtype: 'TrueType'
FontDescriptor: @descriptor
FirstChar: firstChar
LastChar: firstChar + charWidths.length - 1
Widths: @document.ref charWidths
Encoding: 'MacRomanEncoding'
ToUnicode: cmap
for key, val of ref
@ref.data[key] = val
cmap.finalize(@document.compress, fn) # compress it
@ref.end()
toUnicodeCmap = (map) ->
unicodeMap = '''
@ -164,15 +158,18 @@ class PDFFont
end
'''
registerStandard: ->
registerAFM: ->
{@ascender,@decender,@bbox,@lineGap} = @font
@ref = @document.ref
embedAFM: ->
@ref.data =
Type: 'Font'
BaseFont: @filename
Subtype: 'Type1'
Encoding: 'WinAnsiEncoding'
@ref.end()
_standardFonts: [
"Courier"
"Courier-Bold"

37
lib/gradient.coffee
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@ -3,6 +3,7 @@ class PDFGradient
@stops = []
@embedded = no
@transform = [1, 0, 0, 1, 0, 0]
@_colorSpace = 'DeviceRGB'
stop: (pos, color, opacity = 1) ->
opacity = Math.max(0, Math.min(1, opacity))
@ -35,6 +36,7 @@ class PDFGradient
N: 1
stops.push fn
fn.end()
# if there are only two stops, we don't need a stitching function
if stops.length is 1
@ -47,6 +49,8 @@ class PDFGradient
Bounds: bounds
Encode: encode
fn.end()
@id = 'Sh' + (++@doc._gradCount)
# apply gradient transform to existing document ctm
@ -60,26 +64,40 @@ class PDFGradient
m[4] = m0 * dx + m2 * dy + m4
m[5] = m1 * dx + m3 * dy + m5
shader = @shader fn
shader.end()
pattern = @doc.ref
Type: 'Pattern'
PatternType: 2
Shading: @shader fn
Shading: shader
Matrix: (+v.toFixed(5) for v in m)
@doc.page.patterns[@id] = pattern
pattern.end()
if (@stops.some (stop) -> stop[2] < 1)
grad = @opacityGradient()
grad._colorSpace = 'DeviceGray'
for stop in @stops
grad.stop stop[0], [stop[2]]
grad = grad.embed()
grad.data.Shading.data.ColorSpace = 'DeviceGray'
group = @doc.ref
Type: 'Group'
S: 'Transparency'
CS: 'DeviceGray'
group.end()
resources = @doc.ref
ProcSet: ['PDF', 'Text', 'ImageB', 'ImageC', 'ImageI']
Shading:
Sh1: grad.data.Shading
resources.end()
form = @doc.ref
Type: 'XObject'
@ -87,17 +105,16 @@ class PDFGradient
FormType: 1
BBox: [0, 0, @doc.page.width, @doc.page.height]
Group: group
Resources: @doc.ref
ProcSet: ['PDF', 'Text', 'ImageB', 'ImageC', 'ImageI']
Shading:
Sh1: grad.data.Shading
Resources: resources
form.add "/Sh1 sh"
form.end "/Sh1 sh"
sMask = @doc.ref
Type: 'Mask'
S: 'Luminosity'
G: form
sMask.end()
gstate = @doc.ref
Type: 'ExtGState'
@ -107,6 +124,7 @@ class PDFGradient
name = "Gs#{@opacity_id}"
@doc.page.ext_gstates[name] = gstate
gstate.end()
return pattern
@ -115,7 +133,6 @@ class PDFGradient
@doc.addContent "/#{@id} #{op}"
if @opacity_id
@doc.save()
@doc.addContent "/Gs#{@opacity_id} gs"
@doc._sMasked = true
@ -126,7 +143,7 @@ class PDFLinearGradient extends PDFGradient
shader: (fn) ->
@doc.ref
ShadingType: 2
ColorSpace: 'DeviceRGB'
ColorSpace: @_colorSpace
Coords: [@x1, @y1, @x2, @y2]
Function: fn
Extend: [true, true]
@ -141,7 +158,7 @@ class PDFRadialGradient extends PDFGradient
shader: (fn) ->
@doc.ref
ShadingType: 3
ColorSpace: 'DeviceRGB'
ColorSpace: @_colorSpace
Coords: [@x1, @y1, @r1, @x2, @y2, @r2]
Function: fn
Extend: [true, true]

6
lib/image.coffee
View File

@ -9,7 +9,7 @@ JPEG = require './image/jpeg'
PNG = require './image/png'
class PDFImage
@open: (filenameOrBuffer) ->
@open: (filenameOrBuffer, label) ->
if typeof filenameOrBuffer is 'object' and filenameOrBuffer instanceof Buffer
@contents = filenameOrBuffer
else
@ -24,10 +24,10 @@ class PDFImage
firstByte = data.byteAt(0)
if firstByte is 0xFF and data.byteAt(1) is 0xD8
return new JPEG(data)
return new JPEG(data, label)
else if firstByte is 0x89 and data.stringAt(1, 3) is "PNG"
return new PNG(data)
return new PNG(data, label)
else
throw new Error 'Unknown image format.'

14
lib/image/jpeg.coffee
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@ -1,9 +1,8 @@
fs = require 'fs'
Data = '../data'
setImmediate = global.setImmediate ? process.nextTick # backfill for node <0.10
class JPEG
constructor: (@data) ->
constructor: (@data, @label) ->
len = data.length
if data.readUInt16() isnt 0xFFD8
@ -30,10 +29,8 @@ class JPEG
when 3 then 'DeviceRGB'
when 4 then 'DeviceCMYK'
@imgData = @data
object: (document, fn) ->
obj = document.ref
embed: (document) ->
@obj = document.ref
Type: 'XObject'
Subtype: 'Image'
BitsPerComponent: @bits
@ -47,9 +44,8 @@ class JPEG
# min and max values from the default, we invert the colors. See
# section 4.8.4 of the spec.
if @colorSpace is 'DeviceCMYK'
obj.data['Decode'] = [1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0]
@obj.data['Decode'] = [1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0]
obj.add @data.data
setImmediate -> fn(obj)
@obj.end @data.data
module.exports = JPEG

75
lib/image/png.coffee
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@ -1,31 +1,15 @@
zlib = require 'zlib'
PNG = require 'png-js'
setImmediate = global.setImmediate ? process.nextTick # backfill for node <0.10
class PNGImage
constructor: (data) ->
constructor: (data, @label) ->
@image = new PNG(data.data)
@width = @image.width
@height = @image.height
@imgData = @image.imgData
object: (document, fn) ->
# get the async stuff out of the way first
if not @alphaChannel
if @image.transparency.indexed
# Create a transparency SMask for the image based on the data
# in the PLTE and tRNS sections. See below for details on SMasks.
@loadIndexedAlphaChannel => @object document, fn
return
else if @image.hasAlphaChannel
# For PNG color types 4 and 6, the transparency data is stored as a alpha
# channel mixed in with the main image data. Separate this data out into an
# SMask object and store it separately in the PDF.
@splitAlphaChannel => @object document, fn
return
obj = document.ref
embed: (@document) ->
@obj = document.ref
Type: 'XObject'
Subtype: 'Image'
BitsPerComponent: @image.bits
@ -33,25 +17,28 @@ class PNGImage
Height: @height
Length: @imgData.length
Filter: 'FlateDecode'
unless @image.hasAlphaChannel
obj.data['DecodeParms'] = document.ref
params = document.ref
Predictor: 15
Colors: @image.colors
BitsPerComponent: @image.bits
Columns: @width
@obj.data['DecodeParms'] = params
params.end()
if @image.palette.length is 0
obj.data['ColorSpace'] = @image.colorSpace
@obj.data['ColorSpace'] = @image.colorSpace
else
# embed the color palette in the PDF as an object stream
palette = document.ref
Length: @image.palette.length
palette.add new Buffer(@image.palette)
palette.end @image.palette
# build the color space array for the image
obj.data['ColorSpace'] = ['Indexed', 'DeviceRGB', (@image.palette.length / 3) - 1, palette]
@obj.data['ColorSpace'] = ['Indexed', 'DeviceRGB', (@image.palette.length / 3) - 1, palette]
# For PNG color types 0, 2 and 3, the transparency data is stored in
# a dedicated PNG chunk.
@ -59,7 +46,7 @@ class PNGImage
# Use Color Key Masking (spec section 4.8.5)
# An array with N elements, where N is two times the number of color components.
val = @image.transparency.greyscale
obj.data['Mask'] = [val, val]
@obj.data['Mask'] = [val, val]
else if @image.transparency.rgb
# Use Color Key Masking (spec section 4.8.5)
@ -69,10 +56,25 @@ class PNGImage
for x in rgb
mask.push x, x
obj.data['Mask'] = mask
@obj.data['Mask'] = mask
else if @image.transparency.indexed
# Create a transparency SMask for the image based on the data
# in the PLTE and tRNS sections. See below for details on SMasks.
@loadIndexedAlphaChannel()
else if @image.hasAlphaChannel
# For PNG color types 4 and 6, the transparency data is stored as a alpha
# channel mixed in with the main image data. Separate this data out into an
# SMask object and store it separately in the PDF.
@splitAlphaChannel()
else
@finalize()
finalize: ->
if @alphaChannel
sMask = document.ref
sMask = @document.ref
Type: 'XObject'
Subtype: 'Image'
Height: @height
@ -83,14 +85,13 @@ class PNGImage
ColorSpace: 'DeviceGray'
Decode: [0, 1]
sMask.add @alphaChannel
obj.data['SMask'] = sMask
sMask.end @alphaChannel
@obj.data['SMask'] = sMask
# add the actual image data
obj.add @imgData
setImmediate -> fn(obj)
# add the actual image data
@obj.end @imgData
splitAlphaChannel: (fn) ->
splitAlphaChannel: ->
@image.decodePixels (pixels) =>
colorByteSize = @image.colors * @image.bits / 8
pixelCount = @width * @height
@ -108,11 +109,11 @@ class PNGImage
done = 0
zlib.deflate imgData, (err, @imgData) =>
throw err if err
fn() if ++done is 2
@finalize() if ++done is 2
zlib.deflate alphaChannel, (err, @alphaChannel) =>
throw err if err
fn() if ++done is 2
@finalize() if ++done is 2
loadIndexedAlphaChannel: (fn) ->
transparency = @image.transparency.indexed
@ -125,6 +126,6 @@ class PNGImage
zlib.deflate alphaChannel, (err, @alphaChannel) =>
throw err if err
fn()
@finalize()
module.exports = PNGImage

5
lib/mixins/annotations.coffee
View File

@ -15,7 +15,9 @@ module.exports =
for key, val of options
options[key[0].toUpperCase() + key.slice(1)] = val
@page.annotations.push @ref options
ref = @ref options
@page.annotations.push ref
ref.end()
return this
note: (x, y, w, h, contents, options = {}) ->
@ -31,6 +33,7 @@ module.exports =
S: 'URI'
URI: PDFObject.s url
options.A.end()
@annotate x, y, w, h, options
_markup: (x, y, w, h, options = {}) ->

3
lib/mixins/color.coffee
View File

@ -43,9 +43,11 @@ module.exports =
Type: 'ExtGState'
SMask: 'None'
gstate.end()
name = "Gs#{++@_opacityCount}"
@page.ext_gstates[name] = gstate
@addContent "/#{name} gs"
@_sMasked = false
op = if stroke then 'SCN' else 'scn'
@ -108,6 +110,7 @@ module.exports =
dictionary.CA = strokeOpacity if strokeOpacity?
dictionary = @ref dictionary
dictionary.end()
id = ++@_opacityCount
name = "Gs#{id}"
@_opacityRegistry[key] = [dictionary, name]

9
lib/mixins/fonts.coffee
View File

@ -45,11 +45,6 @@ module.exports =
registerFont: (name, path, family) ->
@_registeredFonts[name] =
filename: path
family: family
return this
family: family
embedFonts: (fn) ->
fonts = (font for family, font of @_fontFamilies)
do proceed = =>
return fn() if fonts.length is 0
fonts.shift().embed(proceed)
return this

30
lib/mixins/images.coffee
View File

@ -13,14 +13,13 @@ module.exports =
x = x ? options.x ? @x
y = y ? options.y ? @y
if @_imageRegistry[src]
[image, label, pages] = @_imageRegistry[src]
pages.push @page unless @page in pages
else
image = PDFImage.open(src)
label = "I" + (++@_imageCount)
@_imageRegistry[src] = [image, label, [@page]]
image = @_imageRegistry[src]
if not image
image = PDFImage.open src, 'I' + (++@_imageCount)
image.embed this
@_imageRegistry[src] = image unless Buffer.isBuffer(src)
@page.xobjects[image.label] ?= image.obj
w = options.width or image.width
h = options.height or image.height
@ -60,20 +59,7 @@ module.exports =
@save()
@transform w, 0, 0, -h, x, y + h
@addContent "/#{label} Do"
@addContent "/#{image.label} Do"
@restore()
return this
embedImages: (fn) ->
images = (item for src, item of @_imageRegistry)
do proceed = =>
if images.length
[image, label, pages] = images.shift()
image.object this, (obj) ->
for page in pages
page.xobjects[label] ?= obj
proceed()
else
fn()

57
lib/page.coffee
View File

@ -8,7 +8,7 @@ class PDFPage
@size = options.size or 'letter'
@layout = options.layout or 'portrait'
# if margin was passed as a single number
# process margins
if typeof options.margin is 'number'
@margins =
top: options.margin
@ -19,47 +19,50 @@ class PDFPage
# default to 1 inch margins
else
@margins = options.margins or DEFAULT_MARGINS
# calculate page dimensions
dimensions = if Array.isArray(@size) then @size else SIZES[@size.toUpperCase()]
@width = dimensions[if @layout is 'portrait' then 0 else 1]
@height = dimensions[if @layout is 'portrait' then 1 else 0]
# A reference to the content of this page
@content = @document.ref()
# The page dictionary
@dictionary = @document.ref
Type: 'Page'
Parent: @document.store.pages
MediaBox: [0, 0, @width, @height]
Contents: @content
@content = @document.ref()
# The resource dictionary
@dictionary.data['Resources'] = @document.ref
# Initialize the Font, XObject, and ExtGState dictionaries
@resources = @document.ref
ProcSet: ['PDF', 'Text', 'ImageB', 'ImageC', 'ImageI']
# Initialize the Font, XObject, and ExtGState dictionaries
@resources = @dictionary.data['Resources'].data
# Lazily create these dictionaries
Object.defineProperties this,
fonts:
get: => @resources['Font'] ?= {}
get: => @resources.data.Font ?= {}
xobjects:
get: => @resources['XObject'] ?= {}
get: => @resources.data.XObject ?= {}
ext_gstates:
get: => @resources['ExtGState'] ?= {}
get: => @resources.data.ExtGState ?= {}
patterns:
get: => @resources['Pattern'] ?= {}
get: => @resources.data.Pattern ?= {}
annotations:
get: => @dictionary.data['Annots'] ?= []
get: => @dictionary.data.Annots ?= []
# The page dictionary
@dictionary = @document.ref
Type: 'Page'
Parent: @document._root.data.Pages
MediaBox: [0, 0, @width, @height]
Contents: @content
Resources: @resources
maxY: ->
@height - @margins.bottom
finalize: (fn) ->
@content.finalize(@document.compress, fn)
write: (chunk) ->
@content.write chunk
end: ->
@dictionary.end()
@resources.end()
@content.end()
DEFAULT_MARGINS =
top: 72
left: 72
@ -117,5 +120,5 @@ class PDFPage
LEGAL: [612.00, 1008.00]
LETTER: [612.00, 792.00]
TABLOID: [792.00, 1224.00]
module.exports = PDFPage

96
lib/reference.coffee
View File

@ -4,57 +4,67 @@ By Devon Govett
###
zlib = require 'zlib'
setImmediate = global.setImmediate ? process.nextTick # backfill for node < 0.10
class PDFReference
constructor: (@id, @data = {}) ->
constructor: (@document, @id, @data = {}) ->
@gen = 0
@stream = null
@finalizedStream = null
@deflate = null
@compress = @document.compress and not @data.Filter
@uncompressedLength = 0
@chunks = []
object: (compress, fn) ->
unless @finalizedStream?
return @finalize compress, => @object compress, fn
initDeflate: ->
@data.Filter = 'FlateDecode'
out = ["#{@id} #{@gen} obj"]
out.push PDFObject.convert(@data)
@deflate = zlib.createDeflate()
@deflate.on 'data', (chunk) =>
@chunks.push chunk
@data.Length += chunk.length
@deflate.on 'end', @finalize
write: (chunk) ->
unless Buffer.isBuffer(chunk)
chunk = new Buffer(chunk + '\n', 'binary')
@uncompressedLength += chunk.length
@data.Length ?= 0
if @stream
out.push "stream"
out.push @finalizedStream
out.push "endstream"
out.push "endobj"
fn out.join '\n'
add: (s) ->
@stream ?= []
@stream.push if Buffer.isBuffer(s) then s.toString('binary') else s
finalize: (compress = false, fn) ->
# cache the finalized stream
if @stream
data = @stream.join '\n'
if compress and not @data.Filter
# create a byte array instead of passing a string to the Buffer
# fixes a weird unicode bug.
data = new Buffer(data.charCodeAt(i) for i in [0...data.length])
zlib.deflate data, (err, compressedData) =>
throw err if err
@finalizedStream = compressedData.toString 'binary'
@data.Filter = 'FlateDecode'
@data.Length = @finalizedStream.length
fn()
else
@finalizedStream = data
@data.Length = @finalizedStream.length
setImmediate fn
if @compress
@initDeflate() if not @deflate
@deflate.write chunk
else
@finalizedStream = ''
setImmediate fn
@chunks.push chunk
@data.Length += chunk.length
end: (chunk) ->
if typeof chunk is 'string' or Buffer.isBuffer(chunk)
@write chunk
if @deflate
@deflate.end()
else
@finalize()
finalize: =>
@offset = @document._offset
@document._write "#{@id} #{@gen} obj"
@document._write PDFObject.convert(@data)
if @chunks.length
@document._write 'stream'
for chunk in @chunks
@document._write chunk
@chunks.length = 0 # free up memory
@document._write '\nendstream'
@document._write 'endobj'
@document._refEnd()
toString: ->
"#{@id} #{@gen} R"
return "#{@id} #{@gen} R"
module.exports = PDFReference
PDFObject = require './object'

34
lib/store.coffee
View File

@ -1,34 +0,0 @@
###
PDFObjectStore - stores the object heirarchy for the PDF document
By Devon Govett
###
PDFReference = require './reference'
class PDFObjectStore
constructor: ->
@objects = {}
@length = 0
@root = @ref
Type: 'Catalog'
Pages: @ref
Type: 'Pages'
Count: 0
Kids: []
@pages = @root.data['Pages']
ref: (data) ->
@push ++@length, data
push: (id, data) ->
ref = new PDFReference(id, data)
@objects[id] = ref
return ref
addPage: (page) ->
@pages.data['Kids'].push(page.dictionary)
@pages.data['Count']++
module.exports = PDFObjectStore