Add pageSize option in printToPDF API.

atom/browser/api/lib/web-contents.coffee

@@ -6,6 +6,34 @@ ipc = require 'ipc'
 nextId = 0
 getNextId = -> ++nextId
 
+PDFPageSize =
+  A4:
+    custom_display_name: "A4"
+    height_microns: 297000
+    name: "ISO_A4"
+    is_default: "true"
+    width_microns: 210000
+  A3:
+    custom_display_name: "A3"
+    height_microns: 420000
+    name: "ISO_A3"
+    width_microns: 297000
+  Legal:
+    custom_display_name: "Legal"
+    height_microns: 355600
+    name: "NA_LEGAL"
+    width_microns: 215900
+  Letter:
+    custom_display_name: "Letter"
+    height_microns: 279400
+    name: "NA_LETTER"
+    width_microns: 215900
+  Tabloid:
+    height_microns: 431800
+    name: "NA_LEDGER"
+    width_microns: 279400
+    custom_display_name: "Tabloid"
+
 wrapWebContents = (webContents) ->
   # webContents is an EventEmitter.
   webContents.__proto__ = EventEmitter.prototype
@@ -41,32 +69,27 @@ wrapWebContents = (webContents) ->
 
   webContents.printToPDF = (options, callback) ->
     printingSetting =
-      pageRage:[],
-      mediaSize:
-        height_microns:297000,
-        is_default:true,
-        name:"ISO_A4",
-        width_microns:210000,
-        custom_display_name:"A4",
-      landscape:false,
-      color:2,
-      headerFooterEnabled:false,
-      marginsType:0,
-      isFirstRequest:false,
-      requestID: getNextId(),
-      previewModifiable:true,
-      printToPDF:true,
-      printWithCloudPrint:false,
-      printWithPrivet:false,
-      printWithExtension:false,
-      deviceName:"Save as PDF",
-      generateDraftData:true,
-      fitToPageEnabled:false,
-      duplex:0,
-      copies:1,
-      collate:true,
-      shouldPrintBackgrounds:false,
-      shouldPrintSelectionOnly:false
+      pageRage: []
+      mediaSize: {}
+      landscape: false
+      color: 2
+      headerFooterEnabled: false
+      marginsType: 0
+      isFirstRequest: false
+      requestID: getNextId()
+      previewModifiable: true
+      printToPDF: true
+      printWithCloudPrint: false
+      printWithPrivet: false
+      printWithExtension: false
+      deviceName: "Save as PDF"
+      generateDraftData: true
+      fitToPageEnabled: false
+      duplex: 0
+      copies: 1
+      collate: true
+      shouldPrintBackgrounds: false
+      shouldPrintSelectionOnly: false
 
     if options.landscape
       printingSetting.landscape = options.landscape
@@ -77,6 +100,11 @@ wrapWebContents = (webContents) ->
     if options.printBackgrounds
       printingSetting.shouldPrintBackgrounds = options.printBackground
 
+    if options.pageSize and PDFPageSize[options.pageSize]
+      printingSetting.mediaSize = PDFPageSize[options.pageSize]
+    else
+      printingSetting.mediaSize = PDFPageSize['A4']
+
     @_printToPDF printingSetting, callback
 
 binding._setWrapWebContents wrapWebContents