Store compressed bytes to save mem

src/main/java/io/seqera/storage/DigestByteArray.java

@@ -1,5 +1,7 @@
 package io.seqera.storage;
 
+import io.seqera.util.ZipUtils;
+
 /**
  * @author Paolo Di Tommaso <paolo.ditommaso@gmail.com>
  */
@@ -9,13 +11,13 @@ public class DigestByteArray {
     private String digest;
 
     public DigestByteArray(byte[] bytes, String mediaType, String digest) {
-        this.bytes = bytes;
+        this.bytes = ZipUtils.compress(bytes);
         this.mediaType = mediaType;
         this.digest = digest;
     }
 
     public byte[] getBytes() {
-        return bytes;
+        return ZipUtils.decompressAsBytes(bytes);
     }
 
     public String getMediaType() {

src/main/java/io/seqera/util/ZipUtils.java

@@ -0,0 +1,49 @@
+package io.seqera.util;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.zip.DeflaterInputStream;
+import java.util.zip.InflaterInputStream;
+
+/**
+ * Helper class to basic compress/decompress funcionality
+ *
+ * @author Paolo Di Tommaso <paolo.ditommaso@gmail.com>
+ */
+public class ZipUtils {
+
+    public static byte[] compress(InputStream stream) {
+        try (stream) {
+            return new DeflaterInputStream(stream).readAllBytes();
+        }
+        catch (IOException e) {
+            throw new RuntimeException("Unable to compress provider stream", e);
+        }
+    }
+
+    public static byte[] compress(byte[] bytes) {
+        return compress(new ByteArrayInputStream(bytes));
+    }
+
+    public static byte[] compress(String text) throws IOException {
+        return compress(new ByteArrayInputStream(text.getBytes()));
+    }
+
+    public static InputStream decompress(byte[] buffer) {
+        return new InflaterInputStream(new ByteArrayInputStream(buffer));
+    }
+
+    public static String decompressAsString(byte[] buffer) throws IOException {
+        return new String(decompress(buffer).readAllBytes());
+    }
+
+    public static byte[] decompressAsBytes(byte[] buffer) {
+        try {
+            return decompress(buffer).readAllBytes();
+        }
+        catch (IOException e) {
+            throw new RuntimeException("Unable to decompress provider buffer", e);
+        }
+    }
+}

src/test/groovy/io/seqera/util/ZipUtilsTest.groovy

@@ -0,0 +1,31 @@
+package io.seqera.util
+
+import spock.lang.Specification
+
+/**
+ *
+ * @author Paolo Di Tommaso <paolo.ditommaso@gmail.com>
+ */
+class ZipUtilsTest extends Specification {
+
+    def 'should compress/decompress a text'() {
+        given:
+        def TEXT = 'Hello world\n' * 10
+
+        when:
+        def buffer = ZipUtils.compress(TEXT)
+        then:
+        buffer.size() > 0 && buffer.size() < TEXT.bytes.size()
+
+        when:
+        def copy = ZipUtils.decompressAsString(buffer)
+        then:
+        copy == TEXT
+
+        when:
+        def bytes = ZipUtils.decompressAsBytes(buffer)
+        then:
+        bytes == TEXT.bytes
+    }
+
+}