Merge pull request #2 from scalableminds/fix-sharding-codec

Fix sharding codec

.github/workflows/ci.yml

@@ -11,30 +11,41 @@ jobs:
   build:
     strategy:
       matrix:
-        os: [ ubuntu, windows, macos ]
+        os: [ ubuntu-latest, windows-latest, macos-latest ]
       fail-fast: false
-    runs-on: ${{ matrix.os }}-latest
+    runs-on: ${{ matrix.os }}
     defaults:
       run:
         shell: bash
 
     steps:
       - uses: actions/checkout@v3
+
       - name: Set up JDK
         uses: actions/setup-java@v3
         with:
           java-version: '22'
           distribution: 'temurin'
           cache: maven
 
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.11'
+
+      - name: Install zarrita
+        run: |
+          python -m venv venv_zarrita
+          if [ "${{ runner.os }}" = "Windows" ]; then venv_zarrita/Scripts/pip install zarrita; else venv_zarrita/bin/pip install zarrita; fi
+
       - name: Download blosc jar
         run: |
           mkdir -p ../blosc-java/target
           curl https://static.webknossos.org/misc/blosc-java-0.1-1.21.4-SNAPSHOT.jar -o ../blosc-java/target/blosc-java-0.1-1.21.4-SNAPSHOT.jar
 
       - name: Download testdata
         run: |
-          mkdir testdata testoutput
+          mkdir testoutput
           curl https://static.webknossos.org/data/zarr_v3/l4_sample.zip -o testdata/l4_sample.zip
           cd testdata
           unzip l4_sample.zip
@@ -45,7 +56,7 @@ jobs:
       - name: Test
         env:
           MAVEN_OPTS: "-Xmx6g"
-        run: mvn test -DargLine="-Xmx6g"
+        run: mvn --no-transfer-progress test -DargLine="-Xmx6g"
 
       - name: Assemble JAR
         run: mvn package -DskipTests

.gitignore

@@ -36,5 +36,6 @@ build/
 
 
 ### Custom ###
-/testdata
+/testdata/l4_sample
 /testoutput
+/venv_zarrita

README.md

@@ -38,3 +38,19 @@ array.write(
     ucar.ma2.Array.factory(ucar.ma2.DataType.UINT, new int[]{1, 1024, 1024, 1024})
 );
 ```
+## Development Start-Guide
+
+### Run Tests Locally
+To be able to run the tests locally, make sure to have `python3.11` installed. 
+Also, you need to set up a venv for zarrita at the root of the project:
+`python3.11 -m venv venv_zarrita`.
+
+Then install zarrita there with `venv_zarrita/Scripts/pip install zarrita` 
+for Windows and `venv_zarrita/bin/pip install zarrita` for Linux.
+
+Furthermore, you will need the `l4_sample` test data:
+
+`curl https://static.webknossos.org/data/zarr_v3/l4_sample.zip -o testdata/l4_sample.zip
+&& cd testdata
+&& unzip l4_sample.zip
+`

pom.xml

@@ -16,17 +16,31 @@
         <aws.version>1.12.477</aws.version>
         <netcdfJavaVersion>5.5.3</netcdfJavaVersion>
         <zstdVersion>1.5.5-5</zstdVersion>
-        <junit-jupiter-params.version>5.10.2</junit-jupiter-params.version>
+        <junit-jupiter-version>5.10.2</junit-jupiter-version>
     </properties>
 
     <dependencies>
-        <!-- https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter-params -->
+        <!-- JUnit 5 dependencies -->
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <version>${junit-jupiter-version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <version>${junit-jupiter-version}</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-params</artifactId>
-            <version>${junit-jupiter-params.version}</version>
+            <version>${junit-jupiter-version}</version>
             <scope>test</scope>
         </dependency>
+
+        <!-- Other dependencies -->
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
@@ -62,6 +76,7 @@
             <artifactId>okhttp</artifactId>
             <version>2.7.5</version>
         </dependency>
+        <!-- JUnit 4 dependency for backward compatibility if needed -->
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
@@ -79,6 +94,15 @@
     </repositories>
 
     <build>
-        <testSourceDirectory>src/test/java/dev/zarr/zarrjava</testSourceDirectory>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <version>3.2.5</version>
+                <configuration>
+                    <useSystemClassLoader>false</useSystemClassLoader>
+                </configuration>
+            </plugin>
+        </plugins>
     </build>
-</project>
+</project>

src/main/java/dev/zarr/zarrjava/v3/codec/CodecBuilder.java

@@ -109,23 +109,30 @@ public CodecBuilder withZstd(int clevel) {
   public CodecBuilder withSharding(int[] chunkShape) {
     try {
       codecs.add(
-          new ShardingIndexedCodec(new ShardingIndexedCodec.Configuration(chunkShape,
-              new Codec[]{new BytesCodec(new Configuration(Endian.LITTLE))},
-              new Codec[]{new BytesCodec(new Configuration(Endian.LITTLE)), new Crc32cCodec()})));
+              new ShardingIndexedCodec(new ShardingIndexedCodec.Configuration(chunkShape,
+                      new Codec[]{new BytesCodec(new Configuration(Endian.LITTLE))},
+                      new Codec[]{new BytesCodec(new Configuration(Endian.LITTLE)), new Crc32cCodec()},
+                      "end")));
     } catch (ZarrException e) {
       throw new RuntimeException(e);
     }
     return this;
   }
 
   public CodecBuilder withSharding(int[] chunkShape,
-      Function<CodecBuilder, CodecBuilder> codecBuilder) {
+                                   Function<CodecBuilder, CodecBuilder> codecBuilder) {
+    return withSharding(chunkShape, codecBuilder, "end");
+  }
+
+  public CodecBuilder withSharding(int[] chunkShape,
+                                   Function<CodecBuilder, CodecBuilder> codecBuilder, String indexLocation) {
     CodecBuilder nestedBuilder = new CodecBuilder(dataType);
     try {
       codecs.add(new ShardingIndexedCodec(
-          new ShardingIndexedCodec.Configuration(chunkShape,
-              codecBuilder.apply(nestedBuilder).build(),
-              new Codec[]{new BytesCodec(Endian.LITTLE), new Crc32cCodec()})));
+              new ShardingIndexedCodec.Configuration(chunkShape,
+                      codecBuilder.apply(nestedBuilder).build(),
+                      new Codec[]{new BytesCodec(Endian.LITTLE), new Crc32cCodec()},
+                      indexLocation)));
     } catch (ZarrException e) {
       throw new RuntimeException(e);
     }

src/main/java/dev/zarr/zarrjava/v3/codec/core/ShardingIndexedCodec.java

@@ -133,8 +133,11 @@ public ByteBuffer encode(final Array shardArray) throws ZarrException {
                   final ByteBuffer chunkBytes = codecPipeline.encode(chunkArray);
                   synchronized (chunkBytesList) {
                     int chunkByteOffset = chunkBytesList.stream()
-                        .mapToInt(ByteBuffer::capacity)
-                        .sum();
+                            .mapToInt(ByteBuffer::capacity)
+                            .sum();
+                    if (configuration.indexLocation.equals("start")) {
+                      chunkByteOffset += (int) getShardIndexSize(arrayMetadata);
+                    }
                     setValueFromShardIndexArray(shardIndexArray, chunkCoords, 0, chunkByteOffset);
                     setValueFromShardIndexArray(shardIndexArray, chunkCoords, 1,
                         chunkBytes.capacity());
@@ -149,11 +152,15 @@ public ByteBuffer encode(final Array shardArray) throws ZarrException {
         .mapToInt(ByteBuffer::capacity)
         .sum() + (int) getShardIndexSize(arrayMetadata);
     final ByteBuffer shardBytes = ByteBuffer.allocate(shardBytesLength);
+    if(configuration.indexLocation.equals("start")){
+      shardBytes.put(indexCodecPipeline.encode(shardIndexArray));
+    }
     for (final ByteBuffer chunkBytes : chunkBytesList) {
       shardBytes.put(chunkBytes);
     }
-    shardBytes.put(
-        indexCodecPipeline.encode(shardIndexArray));
+    if(configuration.indexLocation.equals("end")){
+      shardBytes.put(indexCodecPipeline.encode(shardIndexArray));
+    }
     shardBytes.rewind();
     return shardBytes;
   }
@@ -179,8 +186,14 @@ private Array decodeInternal(
 
     final Array outputArray = Array.factory(arrayMetadata.dataType.getMA2DataType(), shape);
     final int shardIndexByteLength = (int) getShardIndexSize(arrayMetadata);
-    ByteBuffer shardIndexBytes = dataProvider.readSuffix(shardIndexByteLength);
-
+    ByteBuffer shardIndexBytes;
+    if (this.configuration.indexLocation.equals("start")) {
+      shardIndexBytes = dataProvider.readPrefix(shardIndexByteLength);
+    }else if(this.configuration.indexLocation.equals("end")){
+      shardIndexBytes = dataProvider.readSuffix(shardIndexByteLength);
+    }else{
+      throw new ZarrException("Only index_location \"start\" or \"end\" are supported.");
+    }
     if (shardIndexBytes == null) {
       throw new ZarrException("Could not read shard index.");
     }
@@ -243,6 +256,8 @@ interface DataProvider {
     ByteBuffer read(long start, long length);
 
     ByteBuffer readSuffix(long suffixLength);
+
+    ByteBuffer readPrefix(long prefixLength);
   }
 
   public static final class Configuration {
@@ -255,16 +270,27 @@ public static final class Configuration {
     @Nonnull
     @JsonProperty("index_codecs")
     public final Codec[] indexCodecs;
+    @Nonnull
+    @JsonProperty("index_location")
+    public String indexLocation;
 
     @JsonCreator(mode = JsonCreator.Mode.PROPERTIES)
     public Configuration(
-        @JsonProperty(value = "chunk_shape", required = true) int[] chunkShape,
-        @Nonnull @JsonProperty("codecs") Codec[] codecs,
-        @Nonnull @JsonProperty("index_codecs") Codec[] indexCodecs
-    ) {
+            @JsonProperty(value = "chunk_shape", required = true) int[] chunkShape,
+            @Nonnull @JsonProperty("codecs") Codec[] codecs,
+            @Nonnull @JsonProperty("index_codecs") Codec[] indexCodecs,
+            @JsonProperty(value = "index_location", defaultValue = "end") String indexLocation
+    ) throws ZarrException {
+      if (indexLocation == null) {
+        indexLocation = "end";
+      }
+      if (!indexLocation.equals("start") && !indexLocation.equals("end")) {
+        throw new ZarrException("Only index_location \"start\" or \"end\" are supported.");
+      }
       this.chunkShape = chunkShape;
       this.codecs = codecs;
       this.indexCodecs = indexCodecs;
+      this.indexLocation = indexLocation;
     }
   }
 
@@ -285,6 +311,12 @@ public ByteBuffer readSuffix(long suffixLength) {
       return bufferSlice.slice();
     }
 
+    public ByteBuffer readPrefix(long prefixLength) {
+      ByteBuffer bufferSlice = buffer.slice();
+      bufferSlice.limit((int) (prefixLength));
+      return bufferSlice.slice();
+    }
+
     @Override
     public ByteBuffer read(long start, long length) {
       ByteBuffer bufferSlice = buffer.slice();
@@ -309,6 +341,11 @@ public ByteBuffer readSuffix(long suffixLength) {
       return storeHandle.read(-suffixLength);
     }
 
+    @Override
+    public ByteBuffer readPrefix(long prefixLength) {
+      return storeHandle.read(0, prefixLength);
+    }
+
     @Override
     public ByteBuffer read(long start, long length) {
       return storeHandle.read(start, start + length);

src/main/java/dev/zarr/zarrjava/v3/codec/core/ZstdCodec.java

@@ -59,7 +59,7 @@ public ByteBuffer encode(ByteBuffer chunkBytes)
       zstdStream.close();
       return ByteBuffer.wrap(outputStream.toByteArray());
     } catch (IOException ex) {
-      throw new ZarrException("Error in decoding zstd.", ex);
+      throw new ZarrException("Error in encoding zstd.", ex);
     }
   }
 

src/test/java/dev/zarr/zarrjava/TestUtils.java

@@ -1,7 +1,8 @@
 package dev.zarr.zarrjava;
 
+
+import org.junit.Test;
 import org.junit.jupiter.api.Assertions;
-import org.junit.jupiter.api.Test;
 
 import java.util.Arrays;