2 files changed, 32 insertions, 27 deletions
diff --git a/lib/utils/batch.js b/lib/utils/batch.js
index 5b92be5..bd3b80f 100644
--- a/lib/utils/batch.js
+++ b/lib/utils/batch.js
@@ -3,6 +3,7 @@ var _ = require("lodash");
 
 // Execute a method for all element
 function execEach(items, options) {
+    if (_.size(items) == 0) return Q();
     var concurrents = 0, d = Q.defer(), pending = [];
 
     options = _.defaults(options || {}, {
diff --git a/lib/utils/page.js b/lib/utils/page.js
index f58e25a..0714958 100644
--- a/lib/utils/page.js
+++ b/lib/utils/page.js
@@ -9,6 +9,7 @@ var crc = require("crc");
 var links = require('./links');
 var imgUtils = require('./images');
 var fs = require('./fs');
+var batch = require('./batch');
 
 // Render a cheerio dom as html
 var renderDom = function($, dom, options) {
@@ -232,33 +233,36 @@ function convertImages(images, options) {
     var downloaded = [];
     options.book.log.debug.ln("convert ", images.length, "images to png");
 
-    return Q.all(_.map(images, function(image) {
-        var imgin = path.resolve(options.book.options.output, image.source);
-
-        return Q()
-
-        // Write image if need to be download
-        .then(function() {
-            if (!image.origin && !_.contains(downloaded, image.origin)) return;
-            options.book.log.debug("download image", image.origin, "...");
-            downloaded.push(image.origin);
-            return options.book.log.debug.promise(fs.writeStream(imgin, request(image.origin)));
-        })
-
-        // Write svg if content
-        .then(function() {
-            if (!image.content) return;
-            return fs.writeFile(imgin, image.content);
-        })
-
-        // Convert
-        .then(function() {
-            if (!image.dest) return;
-            var imgout = path.resolve(options.book.options.output, image.dest);
-            options.book.log.debug("convert image", image.source, "to", image.dest, "...");
-            return options.book.log.debug.promise(imgUtils.convertSVG(imgin, imgout));
-        });
-    }))
+    return batch.execEach(images, {
+        max: 100,
+        fn: function(image) {
+            var imgin = path.resolve(options.book.options.output, image.source);
+
+            return Q()
+
+            // Write image if need to be download
+            .then(function() {
+                if (!image.origin && !_.contains(downloaded, image.origin)) return;
+                options.book.log.debug("download image", image.origin, "...");
+                downloaded.push(image.origin);
+                return options.book.log.debug.promise(fs.writeStream(imgin, request(image.origin)));
+            })
+
+            // Write svg if content
+            .then(function() {
+                if (!image.content) return;
+                return fs.writeFile(imgin, image.content);
+            })
+
+            // Convert
+            .then(function() {
+                if (!image.dest) return;
+                var imgout = path.resolve(options.book.options.output, image.dest);
+                options.book.log.debug("convert image", image.source, "to", image.dest, "...");
+                return options.book.log.debug.promise(imgUtils.convertSVG(imgin, imgout));
+            });
+        }
+    })
     .then(function() {
         options.book.log.debug.ok(images.length+" images converted with success");
     });