Move unzip code into separate module

1 files changed, 72 insertions, 0 deletions

diff --git a/lib/unzip.js b/lib/unzip.js
new file mode 100644
index 0000000..858a4da
--- /dev/null
+++ b/lib/unzip.js
@@ -0,0 +1,72 @@
+exports.unzipUint8Array = unzipUint8Array;
+exports.unzipStream = unzipStream;
+
+var q = require("q");
+var unzip = {
+    Parse: require("unzip/lib/parse")
+};
+var Buffers = require("buffers");
+var streamBuffers = require("stream-buffers");
+
+
+function unzipUint8Array(array) {
+    var buffer = new Buffer(array);
+    var stream = new streamBuffers.ReadableStreamBuffer();
+    stream.put(buffer);
+    return unzipStream(stream);
+}
+
+function unzipStream(stream) {
+    var deferred = q.defer();
+    var names = [];
+    var files = {};
+    
+    stream
+        .pipe(unzip.Parse())
+        .on("entry", function(entry) {
+            names.push(entry.path);
+            files[entry.path] = readEntry(entry);
+        })
+        .on("close", function() {
+            deferred.resolve(zipFile);
+        })
+        .on("error", function(err) {
+            deferred.reject(err);
+        });
+    
+    var exists = function(path) {
+        return names.indexOf(path) !== -1;
+    }
+            
+    function readEntry(entry) {
+        var readDeferred = q.defer();
+        var buffers = new Buffers();
+        
+        entry
+            .on("data", function(data) {
+                buffers.push(data);
+            })
+            .on("end", function() {
+                readDeferred.resolve(buffers);
+            })
+            .on("error", readDeferred.reject.bind(readDeferred))
+            
+        return readDeferred.promise;
+    }
+    var zipFile = {
+        read: function(path, encoding) {
+            if (!exists(path)) {
+                return q.reject(new Error("No file in zip: " + path));
+            }
+            return files[path].then(function(buffer) {
+                if (encoding) {
+                    return buffer.toString(encoding);
+                } else {
+                    return buffer;
+                }
+            });
+        },
+        exists: exists
+    };
+    return deferred.promise;
+}