Add support for writing dz format to zip container (#402)

To enable this you can either use the `.zip` or `.szi` file extensions
or use `.tile({container: 'zip'})` with the `.dzi` extension.

docs/api.md

@@ -527,14 +527,17 @@ The default behaviour, when `withMetadata` is not used, is to strip all metadata
 
 #### tile(options)
 
-The size, overlap and directory layout to use when generating square Deep Zoom image pyramid tiles.
+The size, overlap, container and directory layout to use when generating square Deep Zoom image pyramid tiles.
 
 `options` is an Object with one or more of the following attributes:
 
 * `size` is an integral Number between 1 and 8192. The default value is 256 pixels.
 * `overlap` is an integral Number between 0 and 8192. The default value is 0 pixels.
+* `container` is a String, with value `fs` or `zip`. The default value is `fs`.
 * `layout` is a String, with value `dz`, `zoomify` or `google`. The default value is `dz`.
 
+You can also use the file extension .zip or .szi to write to a ZIP container instead of the filesystem.
+
 ```javascript
 sharp('input.tiff')
   .tile({

index.js

@@ -660,6 +660,14 @@ Sharp.prototype.tile = function(tile) {
         throw new Error('Invalid tile overlap (0 to 8192) ' + tile.overlap);
       }
     }
+    // Container
+    if (isDefined(tile.container)) {
+      if (isString(tile.container) && contains(tile.container, ['fs', 'zip'])) {
+        this.options.tileContainer = tile.container;
+      } else {
+        throw new Error('Invalid tile container ' + tile.container);
+      }
+    }
     // Layout
     if (isDefined(tile.layout)) {
       if (isString(tile.layout) && contains(tile.layout, ['dz', 'google', 'zoomify'])) {

package.json

@@ -58,6 +58,7 @@
   },
   "devDependencies": {
     "async": "^1.5.2",
+    "bufferutil": "^1.2.1",
     "coveralls": "^2.11.9",
     "exif-reader": "^1.0.0",
     "icc": "^0.0.2",
@@ -66,7 +67,7 @@
     "mocha-jshint": "^2.3.1",
     "node-cpplint": "^0.4.0",
     "rimraf": "^2.5.2",
-    "bufferutil": "^1.2.1"
+    "unzip": "^0.1.11"
   },
   "license": "Apache-2.0",
   "config": {

src/common.cc

@@ -52,6 +52,9 @@ namespace sharp {
   bool IsDz(std::string const &str) {
     return EndsWith(str, ".dzi") || EndsWith(str, ".DZI");
   }
+  bool IsDzZip(std::string const &str) {
+    return EndsWith(str, ".zip") || EndsWith(str, ".ZIP") || EndsWith(str, ".szi") || EndsWith(str, ".SZI");
+  }
 
   /*
     Provide a string identifier for the given image type.

src/common.h

@@ -35,6 +35,7 @@ namespace sharp {
   bool IsWebp(std::string const &str);
   bool IsTiff(std::string const &str);
   bool IsDz(std::string const &str);
+  bool IsDzZip(std::string const &str);
 
   /*
     Provide a string identifier for the given image type.

src/pipeline.cc

@@ -65,6 +65,7 @@ using sharp::IsPng;
 using sharp::IsWebp;
 using sharp::IsTiff;
 using sharp::IsDz;
+using sharp::IsDzZip;
 using sharp::FreeCallback;
 using sharp::CalculateCrop;
 using sharp::counterProcess;
@@ -743,7 +744,8 @@ class PipelineWorker : public AsyncWorker {
         bool isWebp = IsWebp(baton->fileOut);
         bool isTiff = IsTiff(baton->fileOut);
         bool isDz = IsDz(baton->fileOut);
-        bool matchInput = baton->formatOut == "input" && !(isJpeg || isPng || isWebp || isTiff || isDz);
+        bool isDzZip = IsDzZip(baton->fileOut);
+        bool matchInput = baton->formatOut == "input" && !(isJpeg || isPng || isWebp || isTiff || isDz || isDzZip);
         if (baton->formatOut == "jpeg" || isJpeg || (matchInput && inputImageType == ImageType::JPEG)) {
           // Write JPEG to file
           image.jpegsave(const_cast<char*>(baton->fileOut.data()), VImage::option()
@@ -784,12 +786,16 @@ class PipelineWorker : public AsyncWorker {
           );
           baton->formatOut = "tiff";
           baton->channels = std::min(baton->channels, 3);
-        } else if (baton->formatOut == "dz" || IsDz(baton->fileOut)) {
+        } else if (baton->formatOut == "dz" || isDz || isDzZip) {
+          if (isDzZip) {
+            baton->tileContainer = VIPS_FOREIGN_DZ_CONTAINER_ZIP;
+          }
           // Write DZ to file
           image.dzsave(const_cast<char*>(baton->fileOut.data()), VImage::option()
             ->set("strip", !baton->withMetadata)
             ->set("tile_size", baton->tileSize)
             ->set("overlap", baton->tileOverlap)
+            ->set("container", baton->tileContainer)
             ->set("layout", baton->tileLayout)
           );
           baton->formatOut = "dz";
@@ -1058,6 +1064,12 @@ NAN_METHOD(pipeline) {
   // Tile output
   baton->tileSize = attrAs<int32_t>(options, "tileSize");
   baton->tileOverlap = attrAs<int32_t>(options, "tileOverlap");
+  std::string tileContainer = attrAsStr(options, "tileContainer");
+  if (tileContainer == "zip") {
+    baton->tileContainer = VIPS_FOREIGN_DZ_CONTAINER_ZIP;
+  } else {
+    baton->tileContainer = VIPS_FOREIGN_DZ_CONTAINER_FS;
+  }
   std::string tileLayout = attrAsStr(options, "tileLayout");
   if (tileLayout == "google") {
     baton->tileLayout = VIPS_FOREIGN_DZ_LAYOUT_GOOGLE;

src/pipeline.h

@@ -81,6 +81,7 @@ struct PipelineBaton {
   int withMetadataOrientation;
   int tileSize;
   int tileOverlap;
+  VipsForeignDzContainer tileContainer;
   VipsForeignDzLayout tileLayout;
 
   PipelineBaton():
@@ -130,6 +131,7 @@ struct PipelineBaton {
     withMetadataOrientation(-1),
     tileSize(256),
     tileOverlap(0),
+    tileContainer(VIPS_FOREIGN_DZ_CONTAINER_FS),
     tileLayout(VIPS_FOREIGN_DZ_LAYOUT_DZ) {
       background[0] = 0.0;
       background[1] = 0.0;

test/unit/tile.js

@@ -6,6 +6,7 @@ var assert = require('assert');
 
 var async = require('async');
 var rimraf = require('rimraf');
+var unzip = require('unzip');
 
 var sharp = require('../../index');
 var fixtures = require('../fixtures');
@@ -88,6 +89,26 @@ describe('Tile', function() {
     });
   });
 
+  it('Valid container values pass', function() {
+    ['fs', 'zip'].forEach(function(container) {
+      assert.doesNotThrow(function() {
+        sharp().tile({
+          container: container
+        });
+      });
+    });
+  });
+
+  it('Invalid container values fail', function() {
+    ['zoinks', 1].forEach(function(container) {
+      assert.throws(function() {
+        sharp().tile({
+          container: container
+        });
+      });
+    });
+  });
+
   it('Valid layout values pass', function() {
     ['dz', 'google', 'zoomify'].forEach(function(layout) {
       assert.doesNotThrow(function() {
@@ -190,6 +211,58 @@ describe('Tile', function() {
       });
     });
 
+    it('Write to ZIP container using file extension', function(done) {
+      var container = fixtures.path('output.dz.container.zip');
+      var extractTo = fixtures.path('output.dz.container');
+      var directory = path.join(extractTo, 'output.dz.container_files');
+      rimraf(directory, function() {
+        sharp(fixtures.inputJpg)
+          .toFile(container, function(err, info) {
+            if (err) throw err;
+            assert.strictEqual('dz', info.format);
+            fs.stat(container, function(err, stat) {
+              if (err) throw err;
+              assert.strictEqual(true, stat.isFile());
+              assert.strictEqual(true, stat.size > 0);
+              fs.createReadStream(container)
+                .pipe(unzip.Extract({path: path.dirname(extractTo)}))
+                .on('error', function(err) { throw err; })
+                .on('close', function() {
+                  assertDeepZoomTiles(directory, 256, 13, done);
+                });
+            });
+          });
+      });
+    });
+
+    it('Write to ZIP container using container tile option', function(done) {
+      var container = fixtures.path('output.dz.containeropt.zip');
+      var extractTo = fixtures.path('output.dz.containeropt');
+      var directory = path.join(extractTo, 'output.dz.containeropt_files');
+      rimraf(directory, function() {
+        sharp(fixtures.inputJpg)
+          .tile({
+            container: 'zip'
+          })
+          .toFile(fixtures.path('output.dz.containeropt.dzi'), function(err, info) {
+            // Vips overrides .dzi extension to .zip used by container var below
+            if (err) throw err;
+            assert.strictEqual('dz', info.format);
+            fs.stat(container, function(err, stat) {
+              if (err) throw err;
+              assert.strictEqual(true, stat.isFile());
+              assert.strictEqual(true, stat.size > 0);
+              fs.createReadStream(container)
+                .pipe(unzip.Extract({path: path.dirname(extractTo)}))
+                .on('error', function(err) { throw err; })
+                .on('close', function() {
+                  assertDeepZoomTiles(directory, 256, 13, done);
+                });
+            });
+          });
+      });
+    });
+
   }
 
 });