james-server-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From adup...@apache.org
Subject [4/5] james-project git commit: JAMES-2583 Change name from Joining to Union
Date Wed, 07 Nov 2018 13:13:07 GMT
JAMES-2583 Change name from Joining to Union


Project: http://git-wip-us.apache.org/repos/asf/james-project/repo
Commit: http://git-wip-us.apache.org/repos/asf/james-project/commit/12a26f95
Tree: http://git-wip-us.apache.org/repos/asf/james-project/tree/12a26f95
Diff: http://git-wip-us.apache.org/repos/asf/james-project/diff/12a26f95

Branch: refs/heads/master
Commit: 12a26f9581e9cb23999cd4a66ebbb2435a8b3ab1
Parents: 4562413
Author: tran tien duc <dtran@linagora.com>
Authored: Tue Nov 6 17:27:42 2018 +0700
Committer: Antoine Duprat <aduprat@linagora.com>
Committed: Wed Nov 7 14:12:19 2018 +0100

----------------------------------------------------------------------
 pom.xml                                         |  10 +-
 server/blob/blob-joining/pom.xml                |  81 -----
 .../james/blob/joining/JoiningBlobStore.java    | 153 ---------
 .../blob/joining/JoiningBlobStoreTest.java      | 333 -------------------
 server/blob/blob-union/pom.xml                  |  81 +++++
 .../apache/james/blob/union/UnionBlobStore.java | 153 +++++++++
 .../james/blob/union/UnionBlobStoreTest.java    | 333 +++++++++++++++++++
 server/blob/pom.xml                             |   2 +-
 8 files changed, 573 insertions(+), 573 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/james-project/blob/12a26f95/pom.xml
----------------------------------------------------------------------
diff --git a/pom.xml b/pom.xml
index f303f8f..59e606e 100644
--- a/pom.xml
+++ b/pom.xml
@@ -1067,11 +1067,6 @@
             </dependency>
             <dependency>
                 <groupId>${james.groupId}</groupId>
-                <artifactId>blob-joining</artifactId>
-                <version>${project.version}</version>
-            </dependency>
-            <dependency>
-                <groupId>${james.groupId}</groupId>
                 <artifactId>blob-objectstorage</artifactId>
                 <version>${project.version}</version>
             </dependency>
@@ -1102,6 +1097,11 @@
                 <artifactId>blob-memory</artifactId>
                 <version>${project.version}</version>
             </dependency>
+            <dependency>
+                <groupId>${james.groupId}</groupId>
+                <artifactId>blob-union</artifactId>
+                <version>${project.version}</version>
+            </dependency>
              <dependency>
                 <groupId>${james.groupId}</groupId>
                 <artifactId>event-sourcing-core</artifactId>

http://git-wip-us.apache.org/repos/asf/james-project/blob/12a26f95/server/blob/blob-joining/pom.xml
----------------------------------------------------------------------
diff --git a/server/blob/blob-joining/pom.xml b/server/blob/blob-joining/pom.xml
deleted file mode 100644
index 74349dd..0000000
--- a/server/blob/blob-joining/pom.xml
+++ /dev/null
@@ -1,81 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!--
-    Licensed to the Apache Software Foundation (ASF) under one
-    or more contributor license agreements. See the NOTICE file
-    distributed with this work for additional information
-    regarding copyright ownership. The ASF licenses this file
-    to you under the Apache License, Version 2.0 (the
-    "License"); you may not use this file except in compliance
-    with the License. You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-    Unless required by applicable law or agreed to in writing,
-    software distributed under the License is distributed on an
-    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-    KIND, either express or implied. See the License for the
-    specific language governing permissions and limitations
-    under the License.
--->
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
-    <modelVersion>4.0.0</modelVersion>
-
-    <parent>
-        <artifactId>james-server-blob</artifactId>
-        <groupId>org.apache.james</groupId>
-        <version>3.2.0-SNAPSHOT</version>
-        <relativePath>../pom.xml</relativePath>
-    </parent>
-
-    <artifactId>blob-joining</artifactId>
-    <packaging>jar</packaging>
-
-    <name>Apache James :: Server :: Blob :: Joining Blob Storages</name>
-    <description>
-        An implementation of BlobStore which relies on a primary and a secondary BlobStore by order for reading.
-        And using primary BlobStore for writing
-    </description>
-
-    <dependencies>
-        <dependency>
-            <groupId>${james.groupId}</groupId>
-            <artifactId>blob-api</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>${james.groupId}</groupId>
-            <artifactId>blob-api</artifactId>
-            <type>test-jar</type>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>${james.groupId}</groupId>
-            <artifactId>blob-memory</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>${james.groupId}</groupId>
-            <artifactId>james-server-testing</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>${james.groupId}</groupId>
-            <artifactId>james-server-util</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.assertj</groupId>
-            <artifactId>assertj-core</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.platform</groupId>
-            <artifactId>junit-platform-launcher</artifactId>
-            <scope>test</scope>
-        </dependency>
-    </dependencies>
-    
-</project>

http://git-wip-us.apache.org/repos/asf/james-project/blob/12a26f95/server/blob/blob-joining/src/main/java/org/apache/james/blob/joining/JoiningBlobStore.java
----------------------------------------------------------------------
diff --git a/server/blob/blob-joining/src/main/java/org/apache/james/blob/joining/JoiningBlobStore.java b/server/blob/blob-joining/src/main/java/org/apache/james/blob/joining/JoiningBlobStore.java
deleted file mode 100644
index aab4cdb..0000000
--- a/server/blob/blob-joining/src/main/java/org/apache/james/blob/joining/JoiningBlobStore.java
+++ /dev/null
@@ -1,153 +0,0 @@
-/****************************************************************
- * Licensed to the Apache Software Foundation (ASF) under one   *
- * or more contributor license agreements.  See the NOTICE file *
- * distributed with this work for additional information        *
- * regarding copyright ownership.  The ASF licenses this file   *
- * to you under the Apache License, Version 2.0 (the            *
- * "License"); you may not use this file except in compliance   *
- * with the License.  You may obtain a copy of the License at   *
- *                                                              *
- *   http://www.apache.org/licenses/LICENSE-2.0                 *
- *                                                              *
- * Unless required by applicable law or agreed to in writing,   *
- * software distributed under the License is distributed on an  *
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
- * KIND, either express or implied.  See the License for the    *
- * specific language governing permissions and limitations      *
- * under the License.                                           *
- ****************************************************************/
-
-package org.apache.james.blob.joining;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.PushbackInputStream;
-import java.util.Optional;
-import java.util.concurrent.CompletableFuture;
-import java.util.function.Function;
-import java.util.function.Supplier;
-
-import org.apache.james.blob.api.BlobId;
-import org.apache.james.blob.api.BlobStore;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import com.github.fge.lambdas.Throwing;
-import com.google.common.annotations.VisibleForTesting;
-
-public class JoiningBlobStore implements BlobStore {
-
-    private static final Logger LOGGER = LoggerFactory.getLogger(JoiningBlobStore.class);
-    private static final int UN_AVAILABLE = -1;
-
-    private final BlobStore primaryBlobStore;
-    private final BlobStore secondaryBlobStore;
-
-    @VisibleForTesting
-    JoiningBlobStore(BlobStore primaryBlobStore, BlobStore secondaryBlobStore) {
-        this.primaryBlobStore = primaryBlobStore;
-        this.secondaryBlobStore = secondaryBlobStore;
-    }
-
-    @Override
-    public CompletableFuture<BlobId> save(byte[] data) {
-        try {
-            return saveToPrimaryFallbackIfFails(
-                primaryBlobStore.save(data),
-                () -> secondaryBlobStore.save(data));
-        } catch (Exception e) {
-            LOGGER.error("exception directly happens while saving bytes data, fall back to secondary blob store", e);
-            return secondaryBlobStore.save(data);
-        }
-    }
-
-    @Override
-    public CompletableFuture<BlobId> save(InputStream data) {
-        try {
-            return saveToPrimaryFallbackIfFails(
-                primaryBlobStore.save(data),
-                () -> secondaryBlobStore.save(data));
-        } catch (Exception e) {
-            LOGGER.error("exception directly happens while saving InputStream data, fall back to secondary blob store", e);
-            return secondaryBlobStore.save(data);
-        }
-    }
-
-    @Override
-    public CompletableFuture<byte[]> readBytes(BlobId blobId) {
-        try {
-            return readBytesFallBackIfFailsOrEmptyResult(blobId);
-        } catch (Exception e) {
-            LOGGER.error("exception directly happens while readBytes, fall back to secondary blob store", e);
-            return secondaryBlobStore.readBytes(blobId);
-        }
-    }
-
-    @Override
-    public InputStream read(BlobId blobId) {
-        try {
-            return readFallBackIfEmptyResult(blobId);
-        } catch (Exception e) {
-            LOGGER.error("exception directly happens while read, fall back to secondary blob store", e);
-            return secondaryBlobStore.read(blobId);
-        }
-    }
-
-    private InputStream readFallBackIfEmptyResult(BlobId blobId) {
-        return Optional.ofNullable(primaryBlobStore.read(blobId))
-            .map(PushbackInputStream::new)
-            .filter(Throwing.predicate(this::streamHasContent).sneakyThrow())
-            .<InputStream>map(Function.identity())
-            .orElseGet(() -> secondaryBlobStore.read(blobId));
-    }
-
-    @VisibleForTesting
-    boolean streamHasContent(PushbackInputStream pushBackIS) throws IOException {
-        int byteRead = pushBackIS.read();
-        if (byteRead != UN_AVAILABLE) {
-            pushBackIS.unread(byteRead);
-            return true;
-        }
-        return false;
-    }
-
-    private CompletableFuture<byte[]> readBytesFallBackIfFailsOrEmptyResult(BlobId blobId) {
-        return primaryBlobStore.readBytes(blobId)
-            .thenApply(Optional::ofNullable)
-            .exceptionally(this::logAndReturnEmptyOptional)
-            .thenCompose(maybeBytes -> readFromSecondaryIfNeeded(maybeBytes, blobId));
-    }
-
-    private CompletableFuture<BlobId> saveToPrimaryFallbackIfFails(
-        CompletableFuture<BlobId> primarySavingOperation,
-        Supplier<CompletableFuture<BlobId>> fallbackSavingOperationSupplier) {
-
-        return primarySavingOperation
-            .thenApply(Optional::ofNullable)
-            .exceptionally(this::logAndReturnEmptyOptional)
-            .thenCompose(maybeBlobId -> saveToSecondaryIfNeeded(maybeBlobId, fallbackSavingOperationSupplier));
-    }
-
-    private <T> Optional<T> logAndReturnEmptyOptional(Throwable throwable) {
-        LOGGER.error("primary completed exceptionally, fall back to second blob store", throwable);
-        return Optional.empty();
-    }
-
-    private CompletableFuture<BlobId> saveToSecondaryIfNeeded(Optional<BlobId> maybeBlobId,
-                                                              Supplier<CompletableFuture<BlobId>> saveToSecondarySupplier) {
-        return maybeBlobId
-            .map(CompletableFuture::completedFuture)
-            .orElseGet(saveToSecondarySupplier);
-    }
-
-    private CompletableFuture<byte[]> readFromSecondaryIfNeeded(Optional<byte[]> readFromPrimaryResult, BlobId blodId) {
-        return readFromPrimaryResult
-            .filter(this::hasContent)
-            .map(CompletableFuture::completedFuture)
-            .orElseGet(() -> secondaryBlobStore.readBytes(blodId));
-    }
-
-    private boolean hasContent(byte [] bytes) {
-        return bytes.length > 0;
-    }
-}

http://git-wip-us.apache.org/repos/asf/james-project/blob/12a26f95/server/blob/blob-joining/src/test/java/org/apache/james/blob/joining/JoiningBlobStoreTest.java
----------------------------------------------------------------------
diff --git a/server/blob/blob-joining/src/test/java/org/apache/james/blob/joining/JoiningBlobStoreTest.java b/server/blob/blob-joining/src/test/java/org/apache/james/blob/joining/JoiningBlobStoreTest.java
deleted file mode 100644
index 329dd92..0000000
--- a/server/blob/blob-joining/src/test/java/org/apache/james/blob/joining/JoiningBlobStoreTest.java
+++ /dev/null
@@ -1,333 +0,0 @@
-/****************************************************************
- * Licensed to the Apache Software Foundation (ASF) under one   *
- * or more contributor license agreements.  See the NOTICE file *
- * distributed with this work for additional information        *
- * regarding copyright ownership.  The ASF licenses this file   *
- * to you under the Apache License, Version 2.0 (the            *
- * "License"); you may not use this file except in compliance   *
- * with the License.  You may obtain a copy of the License at   *
- *                                                              *
- *   http://www.apache.org/licenses/LICENSE-2.0                 *
- *                                                              *
- * Unless required by applicable law or agreed to in writing,   *
- * software distributed under the License is distributed on an  *
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
- * KIND, either express or implied.  See the License for the    *
- * specific language governing permissions and limitations      *
- * under the License.                                           *
- ****************************************************************/
-
-package org.apache.james.blob.joining;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatCode;
-
-import java.io.ByteArrayInputStream;
-import java.io.InputStream;
-import java.io.PushbackInputStream;
-import java.util.concurrent.CompletableFuture;
-
-import org.apache.james.blob.api.BlobId;
-import org.apache.james.blob.api.BlobStore;
-import org.apache.james.blob.api.BlobStoreContract;
-import org.apache.james.blob.api.HashBlobId;
-import org.apache.james.blob.memory.MemoryBlobStore;
-import org.apache.james.util.CompletableFutureUtil;
-import org.assertj.core.api.SoftAssertions;
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Nested;
-import org.junit.jupiter.api.Test;
-
-class JoiningBlobStoreTest implements BlobStoreContract {
-
-    private static class FutureThrowingBlobStore implements BlobStore {
-
-        @Override
-        public CompletableFuture<BlobId> save(byte[] data) {
-            return CompletableFutureUtil.exceptionallyFuture(new RuntimeException("not supported"));
-        }
-
-        @Override
-        public CompletableFuture<BlobId> save(InputStream data) {
-            return CompletableFutureUtil.exceptionallyFuture(new RuntimeException("not supported"));
-        }
-
-        @Override
-        public CompletableFuture<byte[]> readBytes(BlobId blobId) {
-            return CompletableFutureUtil.exceptionallyFuture(new RuntimeException("not supported"));
-        }
-
-        @Override
-        public InputStream read(BlobId blobId) {
-            throw new RuntimeException("not supported");
-        }
-    }
-
-    private static class ThrowingBlobStore implements BlobStore {
-
-        @Override
-        public CompletableFuture<BlobId> save(byte[] data) {
-            throw new RuntimeException("not supported");
-        }
-
-        @Override
-        public CompletableFuture<BlobId> save(InputStream data) {
-            throw new RuntimeException("not supported");
-        }
-
-        @Override
-        public CompletableFuture<byte[]> readBytes(BlobId blobId) {
-            throw new RuntimeException("not supported");
-        }
-
-        @Override
-        public InputStream read(BlobId blobId) {
-            throw new RuntimeException("not supported");
-        }
-    }
-
-    private static final HashBlobId.Factory BLOB_ID_FACTORY = new HashBlobId.Factory();
-    private static final byte [] BLOB_CONTENT = "blob content".getBytes();
-
-    private MemoryBlobStore primaryBlobStore;
-    private MemoryBlobStore secondaryBlobStore;
-    private JoiningBlobStore joiningBlobStore;
-
-    @BeforeEach
-    void setup() {
-        primaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-        secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-        joiningBlobStore = new JoiningBlobStore(primaryBlobStore, secondaryBlobStore);
-    }
-
-    @Override
-    public BlobStore testee() {
-        return joiningBlobStore;
-    }
-
-    @Override
-    public BlobId.Factory blobIdFactory() {
-        return BLOB_ID_FACTORY;
-    }
-
-    @Nested
-    class PrimarySaveThrowsExceptionDirectly {
-
-        @Test
-        void saveShouldFallBackToSecondaryWhenPrimaryGotException() throws Exception {
-            MemoryBlobStore secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-            JoiningBlobStore joiningBlobStore = new JoiningBlobStore(new ThrowingBlobStore(), secondaryBlobStore);
-            BlobId blobId = joiningBlobStore.save(BLOB_CONTENT).get();
-
-            SoftAssertions.assertSoftly(softly -> {
-                softly.assertThat(joiningBlobStore.read(blobId))
-                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-                softly.assertThat(secondaryBlobStore.read(blobId))
-                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-            });
-        }
-
-        @Test
-        void saveInputStreamShouldFallBackToSecondaryWhenPrimaryGotException() throws Exception {
-            MemoryBlobStore secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-            JoiningBlobStore joiningBlobStore = new JoiningBlobStore(new ThrowingBlobStore(), secondaryBlobStore);
-            BlobId blobId = joiningBlobStore.save(new ByteArrayInputStream(BLOB_CONTENT)).get();
-
-            SoftAssertions.assertSoftly(softly -> {
-                softly.assertThat(joiningBlobStore.read(blobId))
-                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-                softly.assertThat(secondaryBlobStore.read(blobId))
-                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-            });
-        }
-    }
-
-    @Nested
-    class PrimarySaveCompletesExceptionally {
-
-        @Test
-        void saveShouldFallBackToSecondaryWhenPrimaryCompletedExceptionally() throws Exception {
-            MemoryBlobStore secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-            JoiningBlobStore joiningBlobStore = new JoiningBlobStore(new FutureThrowingBlobStore(), secondaryBlobStore);
-            BlobId blobId = joiningBlobStore.save(BLOB_CONTENT).get();
-
-            SoftAssertions.assertSoftly(softly -> {
-                softly.assertThat(joiningBlobStore.read(blobId))
-                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-                softly.assertThat(secondaryBlobStore.read(blobId))
-                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-            });
-        }
-
-        @Test
-        void saveInputStreamShouldFallBackToSecondaryWhenPrimaryCompletedExceptionally() throws Exception {
-            MemoryBlobStore secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-            JoiningBlobStore joiningBlobStore = new JoiningBlobStore(new FutureThrowingBlobStore(), secondaryBlobStore);
-            BlobId blobId = joiningBlobStore.save(new ByteArrayInputStream(BLOB_CONTENT)).get();
-
-            SoftAssertions.assertSoftly(softly -> {
-                softly.assertThat(joiningBlobStore.read(blobId))
-                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-                softly.assertThat(secondaryBlobStore.read(blobId))
-                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-            });
-        }
-
-    }
-
-    @Nested
-    class PrimaryReadThrowsExceptionDirectly {
-
-        @Test
-        void readShouldReturnFallbackToSecondaryWhenPrimaryGotException() throws Exception {
-            MemoryBlobStore secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-            JoiningBlobStore joiningBlobStore = new JoiningBlobStore(new ThrowingBlobStore(), secondaryBlobStore);
-            BlobId blobId = secondaryBlobStore.save(BLOB_CONTENT).get();
-
-            assertThat(joiningBlobStore.read(blobId))
-                .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-        }
-
-        @Test
-        void readBytesShouldReturnFallbackToSecondaryWhenPrimaryGotException() throws Exception {
-            MemoryBlobStore secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-            JoiningBlobStore joiningBlobStore = new JoiningBlobStore(new ThrowingBlobStore(), secondaryBlobStore);
-            BlobId blobId = secondaryBlobStore.save(BLOB_CONTENT).get();
-
-            assertThat(joiningBlobStore.readBytes(blobId).get())
-                .isEqualTo(BLOB_CONTENT);
-        }
-
-    }
-
-    @Nested
-    class PrimaryReadCompletesExceptionally {
-
-        @Test
-        void readShouldReturnFallbackToSecondaryWhenPrimaryCompletedExceptionally() throws Exception {
-            MemoryBlobStore secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-            JoiningBlobStore joiningBlobStore = new JoiningBlobStore(new FutureThrowingBlobStore(), secondaryBlobStore);
-            BlobId blobId = secondaryBlobStore.save(BLOB_CONTENT).get();
-
-            assertThat(joiningBlobStore.read(blobId))
-                .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-        }
-
-        @Test
-        void readBytesShouldReturnFallbackToSecondaryWhenPrimaryCompletedExceptionally() throws Exception {
-            MemoryBlobStore secondaryBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
-            JoiningBlobStore joiningBlobStore = new JoiningBlobStore(new FutureThrowingBlobStore(), secondaryBlobStore);
-            BlobId blobId = secondaryBlobStore.save(BLOB_CONTENT).get();
-
-            assertThat(joiningBlobStore.readBytes(blobId).get())
-                .isEqualTo(BLOB_CONTENT);
-        }
-    }
-
-
-    @Test
-    void readShouldReturnFromPrimaryWhenAvailable() throws Exception {
-        BlobId blobId = primaryBlobStore.save(BLOB_CONTENT).get();
-
-        assertThat(joiningBlobStore.read(blobId))
-            .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-    }
-
-    @Test
-    void readShouldReturnFromSecondaryWhenPrimaryNotAvailable() throws Exception {
-        BlobId blobId = secondaryBlobStore.save(BLOB_CONTENT).get();
-
-        assertThat(joiningBlobStore.read(blobId))
-            .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-    }
-
-    @Test
-    void readBytesShouldReturnFromPrimaryWhenAvailable() throws Exception {
-        BlobId blobId = primaryBlobStore.save(BLOB_CONTENT).get();
-
-        assertThat(joiningBlobStore.readBytes(blobId).get())
-            .isEqualTo(BLOB_CONTENT);
-    }
-
-    @Test
-    void readBytesShouldReturnFromSecondaryWhenPrimaryNotAvailable() throws Exception {
-        BlobId blobId = secondaryBlobStore.save(BLOB_CONTENT).get();
-
-        assertThat(joiningBlobStore.readBytes(blobId).get())
-            .isEqualTo(BLOB_CONTENT);
-    }
-
-    @Test
-    void saveShouldWriteToPrimary() throws Exception {
-        BlobId blobId = joiningBlobStore.save(BLOB_CONTENT).get();
-
-        assertThat(primaryBlobStore.readBytes(blobId).get())
-            .isEqualTo(BLOB_CONTENT);
-    }
-
-    @Test
-    void saveShouldNotWriteToSecondary() throws Exception {
-        BlobId blobId = joiningBlobStore.save(BLOB_CONTENT).get();
-
-        assertThat(secondaryBlobStore.readBytes(blobId).get())
-            .isEmpty();
-    }
-
-    @Test
-    void saveInputStreamShouldWriteToPrimary() throws Exception {
-        BlobId blobId = joiningBlobStore.save(new ByteArrayInputStream(BLOB_CONTENT)).get();
-
-        assertThat(primaryBlobStore.readBytes(blobId).get())
-            .isEqualTo(BLOB_CONTENT);
-    }
-
-    @Test
-    void saveInputStreamShouldNotWriteToSecondary() throws Exception {
-        BlobId blobId = joiningBlobStore.save(new ByteArrayInputStream(BLOB_CONTENT)).get();
-
-        assertThat(secondaryBlobStore.readBytes(blobId).get())
-            .isEmpty();
-    }
-
-    @Test
-    void streamHasContentShouldReturnTrueWhenStreamHasContent() throws Exception {
-        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(BLOB_CONTENT));
-
-        assertThat(joiningBlobStore.streamHasContent(pushBackIS))
-            .isTrue();
-    }
-
-    @Test
-    void streamHasContentShouldReturnFalseWhenStreamHasNoContent() throws Exception {
-        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(new byte[0]));
-
-        assertThat(joiningBlobStore.streamHasContent(pushBackIS))
-            .isFalse();
-    }
-
-    @Test
-    void streamHasContentShouldNotThrowWhenStreamHasNoContent() {
-        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(new byte[0]));
-
-        assertThatCode(() -> joiningBlobStore.streamHasContent(pushBackIS))
-            .doesNotThrowAnyException();
-    }
-
-    @Test
-    void streamHasContentShouldNotDrainPushBackStreamContent() throws Exception {
-        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(BLOB_CONTENT));
-        joiningBlobStore.streamHasContent(pushBackIS);
-
-        assertThat(pushBackIS)
-            .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
-    }
-
-    @Test
-    void streamHasContentShouldKeepStreamEmptyWhenStreamIsEmpty() throws Exception {
-        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(new byte[0]));
-        joiningBlobStore.streamHasContent(pushBackIS);
-
-        assertThat(pushBackIS)
-            .hasSameContentAs(new ByteArrayInputStream(new byte[0]));
-    }
-}
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/james-project/blob/12a26f95/server/blob/blob-union/pom.xml
----------------------------------------------------------------------
diff --git a/server/blob/blob-union/pom.xml b/server/blob/blob-union/pom.xml
new file mode 100644
index 0000000..5a6e84f
--- /dev/null
+++ b/server/blob/blob-union/pom.xml
@@ -0,0 +1,81 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+    Licensed to the Apache Software Foundation (ASF) under one
+    or more contributor license agreements. See the NOTICE file
+    distributed with this work for additional information
+    regarding copyright ownership. The ASF licenses this file
+    to you under the Apache License, Version 2.0 (the
+    "License"); you may not use this file except in compliance
+    with the License. You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing,
+    software distributed under the License is distributed on an
+    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+    KIND, either express or implied. See the License for the
+    specific language governing permissions and limitations
+    under the License.
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <artifactId>james-server-blob</artifactId>
+        <groupId>org.apache.james</groupId>
+        <version>3.2.0-SNAPSHOT</version>
+        <relativePath>../pom.xml</relativePath>
+    </parent>
+
+    <artifactId>blob-union</artifactId>
+    <packaging>jar</packaging>
+
+    <name>Apache James :: Server :: Blob :: Union Blob Storage</name>
+    <description>
+        An implementation of BlobStore which relies on a current and a legacy BlobStore by order for reading and writing
+        blobs with fallback mechanism.
+    </description>
+
+    <dependencies>
+        <dependency>
+            <groupId>${james.groupId}</groupId>
+            <artifactId>blob-api</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>${james.groupId}</groupId>
+            <artifactId>blob-api</artifactId>
+            <type>test-jar</type>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>${james.groupId}</groupId>
+            <artifactId>blob-memory</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>${james.groupId}</groupId>
+            <artifactId>james-server-testing</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>${james.groupId}</groupId>
+            <artifactId>james-server-util</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.platform</groupId>
+            <artifactId>junit-platform-launcher</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+    
+</project>

http://git-wip-us.apache.org/repos/asf/james-project/blob/12a26f95/server/blob/blob-union/src/main/java/org/apache/james/blob/union/UnionBlobStore.java
----------------------------------------------------------------------
diff --git a/server/blob/blob-union/src/main/java/org/apache/james/blob/union/UnionBlobStore.java b/server/blob/blob-union/src/main/java/org/apache/james/blob/union/UnionBlobStore.java
new file mode 100644
index 0000000..9d87213
--- /dev/null
+++ b/server/blob/blob-union/src/main/java/org/apache/james/blob/union/UnionBlobStore.java
@@ -0,0 +1,153 @@
+/****************************************************************
+ * Licensed to the Apache Software Foundation (ASF) under one   *
+ * or more contributor license agreements.  See the NOTICE file *
+ * distributed with this work for additional information        *
+ * regarding copyright ownership.  The ASF licenses this file   *
+ * to you under the Apache License, Version 2.0 (the            *
+ * "License"); you may not use this file except in compliance   *
+ * with the License.  You may obtain a copy of the License at   *
+ *                                                              *
+ *   http://www.apache.org/licenses/LICENSE-2.0                 *
+ *                                                              *
+ * Unless required by applicable law or agreed to in writing,   *
+ * software distributed under the License is distributed on an  *
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
+ * KIND, either express or implied.  See the License for the    *
+ * specific language governing permissions and limitations      *
+ * under the License.                                           *
+ ****************************************************************/
+
+package org.apache.james.blob.union;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.PushbackInputStream;
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+import java.util.function.Function;
+import java.util.function.Supplier;
+
+import org.apache.james.blob.api.BlobId;
+import org.apache.james.blob.api.BlobStore;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.github.fge.lambdas.Throwing;
+import com.google.common.annotations.VisibleForTesting;
+
+public class UnionBlobStore implements BlobStore {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(UnionBlobStore.class);
+    private static final int UNAVAILABLE = -1;
+
+    private final BlobStore currentBlobStore;
+    private final BlobStore legacyBlobStore;
+
+    @VisibleForTesting
+    UnionBlobStore(BlobStore currentBlobStore, BlobStore legacyBlobStore) {
+        this.currentBlobStore = currentBlobStore;
+        this.legacyBlobStore = legacyBlobStore;
+    }
+
+    @Override
+    public CompletableFuture<BlobId> save(byte[] data) {
+        try {
+            return saveToCurrentFallbackIfFails(
+                currentBlobStore.save(data),
+                () -> legacyBlobStore.save(data));
+        } catch (Exception e) {
+            LOGGER.error("exception directly happens while saving bytes data, fall back to legacy blob store", e);
+            return legacyBlobStore.save(data);
+        }
+    }
+
+    @Override
+    public CompletableFuture<BlobId> save(InputStream data) {
+        try {
+            return saveToCurrentFallbackIfFails(
+                currentBlobStore.save(data),
+                () -> legacyBlobStore.save(data));
+        } catch (Exception e) {
+            LOGGER.error("exception directly happens while saving InputStream data, fall back to legacy blob store", e);
+            return legacyBlobStore.save(data);
+        }
+    }
+
+    @Override
+    public CompletableFuture<byte[]> readBytes(BlobId blobId) {
+        try {
+            return readBytesFallBackIfFailsOrEmptyResult(blobId);
+        } catch (Exception e) {
+            LOGGER.error("exception directly happens while readBytes, fall back to legacy blob store", e);
+            return legacyBlobStore.readBytes(blobId);
+        }
+    }
+
+    @Override
+    public InputStream read(BlobId blobId) {
+        try {
+            return readFallBackIfEmptyResult(blobId);
+        } catch (Exception e) {
+            LOGGER.error("exception directly happens while read, fall back to legacy blob store", e);
+            return legacyBlobStore.read(blobId);
+        }
+    }
+
+    private InputStream readFallBackIfEmptyResult(BlobId blobId) {
+        return Optional.ofNullable(currentBlobStore.read(blobId))
+            .map(PushbackInputStream::new)
+            .filter(Throwing.predicate(this::streamHasContent).sneakyThrow())
+            .<InputStream>map(Function.identity())
+            .orElseGet(() -> legacyBlobStore.read(blobId));
+    }
+
+    @VisibleForTesting
+    boolean streamHasContent(PushbackInputStream pushBackIS) throws IOException {
+        int byteRead = pushBackIS.read();
+        if (byteRead != UNAVAILABLE) {
+            pushBackIS.unread(byteRead);
+            return true;
+        }
+        return false;
+    }
+
+    private CompletableFuture<byte[]> readBytesFallBackIfFailsOrEmptyResult(BlobId blobId) {
+        return currentBlobStore.readBytes(blobId)
+            .thenApply(Optional::ofNullable)
+            .exceptionally(this::logAndReturnEmptyOptional)
+            .thenCompose(maybeBytes -> readFromLegacyIfNeeded(maybeBytes, blobId));
+    }
+
+    private CompletableFuture<BlobId> saveToCurrentFallbackIfFails(
+        CompletableFuture<BlobId> currentSavingOperation,
+        Supplier<CompletableFuture<BlobId>> fallbackSavingOperationSupplier) {
+
+        return currentSavingOperation
+            .thenApply(Optional::ofNullable)
+            .exceptionally(this::logAndReturnEmptyOptional)
+            .thenCompose(maybeBlobId -> saveToLegacyIfNeeded(maybeBlobId, fallbackSavingOperationSupplier));
+    }
+
+    private <T> Optional<T> logAndReturnEmptyOptional(Throwable throwable) {
+        LOGGER.error("error happens from current blob store, fall back to legacy blob store", throwable);
+        return Optional.empty();
+    }
+
+    private CompletableFuture<BlobId> saveToLegacyIfNeeded(Optional<BlobId> maybeBlobId,
+                                                           Supplier<CompletableFuture<BlobId>> saveToLegacySupplier) {
+        return maybeBlobId
+            .map(CompletableFuture::completedFuture)
+            .orElseGet(saveToLegacySupplier);
+    }
+
+    private CompletableFuture<byte[]> readFromLegacyIfNeeded(Optional<byte[]> readFromCurrentResult, BlobId blodId) {
+        return readFromCurrentResult
+            .filter(this::hasContent)
+            .map(CompletableFuture::completedFuture)
+            .orElseGet(() -> legacyBlobStore.readBytes(blodId));
+    }
+
+    private boolean hasContent(byte [] bytes) {
+        return bytes.length > 0;
+    }
+}

http://git-wip-us.apache.org/repos/asf/james-project/blob/12a26f95/server/blob/blob-union/src/test/java/org/apache/james/blob/union/UnionBlobStoreTest.java
----------------------------------------------------------------------
diff --git a/server/blob/blob-union/src/test/java/org/apache/james/blob/union/UnionBlobStoreTest.java b/server/blob/blob-union/src/test/java/org/apache/james/blob/union/UnionBlobStoreTest.java
new file mode 100644
index 0000000..9afa0f9
--- /dev/null
+++ b/server/blob/blob-union/src/test/java/org/apache/james/blob/union/UnionBlobStoreTest.java
@@ -0,0 +1,333 @@
+/****************************************************************
+ * Licensed to the Apache Software Foundation (ASF) under one   *
+ * or more contributor license agreements.  See the NOTICE file *
+ * distributed with this work for additional information        *
+ * regarding copyright ownership.  The ASF licenses this file   *
+ * to you under the Apache License, Version 2.0 (the            *
+ * "License"); you may not use this file except in compliance   *
+ * with the License.  You may obtain a copy of the License at   *
+ *                                                              *
+ *   http://www.apache.org/licenses/LICENSE-2.0                 *
+ *                                                              *
+ * Unless required by applicable law or agreed to in writing,   *
+ * software distributed under the License is distributed on an  *
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
+ * KIND, either express or implied.  See the License for the    *
+ * specific language governing permissions and limitations      *
+ * under the License.                                           *
+ ****************************************************************/
+
+package org.apache.james.blob.union;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatCode;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.io.PushbackInputStream;
+import java.util.concurrent.CompletableFuture;
+
+import org.apache.james.blob.api.BlobId;
+import org.apache.james.blob.api.BlobStore;
+import org.apache.james.blob.api.BlobStoreContract;
+import org.apache.james.blob.api.HashBlobId;
+import org.apache.james.blob.memory.MemoryBlobStore;
+import org.apache.james.util.CompletableFutureUtil;
+import org.assertj.core.api.SoftAssertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+class UnionBlobStoreTest implements BlobStoreContract {
+
+    private static class FutureThrowingBlobStore implements BlobStore {
+
+        @Override
+        public CompletableFuture<BlobId> save(byte[] data) {
+            return CompletableFutureUtil.exceptionallyFuture(new RuntimeException("broken everywhere"));
+        }
+
+        @Override
+        public CompletableFuture<BlobId> save(InputStream data) {
+            return CompletableFutureUtil.exceptionallyFuture(new RuntimeException("broken everywhere"));
+        }
+
+        @Override
+        public CompletableFuture<byte[]> readBytes(BlobId blobId) {
+            return CompletableFutureUtil.exceptionallyFuture(new RuntimeException("broken everywhere"));
+        }
+
+        @Override
+        public InputStream read(BlobId blobId) {
+            throw new RuntimeException("broken everywhere");
+        }
+    }
+
+    private static class ThrowingBlobStore implements BlobStore {
+
+        @Override
+        public CompletableFuture<BlobId> save(byte[] data) {
+            throw new RuntimeException("broken everywhere");
+        }
+
+        @Override
+        public CompletableFuture<BlobId> save(InputStream data) {
+            throw new RuntimeException("broken everywhere");
+        }
+
+        @Override
+        public CompletableFuture<byte[]> readBytes(BlobId blobId) {
+            throw new RuntimeException("broken everywhere");
+        }
+
+        @Override
+        public InputStream read(BlobId blobId) {
+            throw new RuntimeException("broken everywhere");
+        }
+    }
+
+    private static final HashBlobId.Factory BLOB_ID_FACTORY = new HashBlobId.Factory();
+    private static final byte [] BLOB_CONTENT = "blob content".getBytes();
+
+    private MemoryBlobStore currentBlobStore;
+    private MemoryBlobStore legacyBlobStore;
+    private UnionBlobStore unionBlobStore;
+
+    @BeforeEach
+    void setup() {
+        currentBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+        legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+        unionBlobStore = new UnionBlobStore(currentBlobStore, legacyBlobStore);
+    }
+
+    @Override
+    public BlobStore testee() {
+        return unionBlobStore;
+    }
+
+    @Override
+    public BlobId.Factory blobIdFactory() {
+        return BLOB_ID_FACTORY;
+    }
+
+    @Nested
+    class CurrentSaveThrowsExceptionDirectly {
+
+        @Test
+        void saveShouldFallBackToLegacyWhenCurrentGotException() throws Exception {
+            MemoryBlobStore legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+            UnionBlobStore unionBlobStore = new UnionBlobStore(new ThrowingBlobStore(), legacyBlobStore);
+            BlobId blobId = unionBlobStore.save(BLOB_CONTENT).get();
+
+            SoftAssertions.assertSoftly(softly -> {
+                softly.assertThat(unionBlobStore.read(blobId))
+                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+                softly.assertThat(legacyBlobStore.read(blobId))
+                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+            });
+        }
+
+        @Test
+        void saveInputStreamShouldFallBackToLegacyWhenCurrentGotException() throws Exception {
+            MemoryBlobStore legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+            UnionBlobStore unionBlobStore = new UnionBlobStore(new ThrowingBlobStore(), legacyBlobStore);
+            BlobId blobId = unionBlobStore.save(new ByteArrayInputStream(BLOB_CONTENT)).get();
+
+            SoftAssertions.assertSoftly(softly -> {
+                softly.assertThat(unionBlobStore.read(blobId))
+                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+                softly.assertThat(legacyBlobStore.read(blobId))
+                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+            });
+        }
+    }
+
+    @Nested
+    class CurrentSaveCompletesExceptionally {
+
+        @Test
+        void saveShouldFallBackToLegacyWhenCurrentCompletedExceptionally() throws Exception {
+            MemoryBlobStore legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+            UnionBlobStore unionBlobStore = new UnionBlobStore(new FutureThrowingBlobStore(), legacyBlobStore);
+            BlobId blobId = unionBlobStore.save(BLOB_CONTENT).get();
+
+            SoftAssertions.assertSoftly(softly -> {
+                softly.assertThat(unionBlobStore.read(blobId))
+                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+                softly.assertThat(legacyBlobStore.read(blobId))
+                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+            });
+        }
+
+        @Test
+        void saveInputStreamShouldFallBackToLegacyWhenCurrentCompletedExceptionally() throws Exception {
+            MemoryBlobStore legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+            UnionBlobStore unionBlobStore = new UnionBlobStore(new FutureThrowingBlobStore(), legacyBlobStore);
+            BlobId blobId = unionBlobStore.save(new ByteArrayInputStream(BLOB_CONTENT)).get();
+
+            SoftAssertions.assertSoftly(softly -> {
+                softly.assertThat(unionBlobStore.read(blobId))
+                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+                softly.assertThat(legacyBlobStore.read(blobId))
+                    .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+            });
+        }
+
+    }
+
+    @Nested
+    class CurrentReadThrowsExceptionDirectly {
+
+        @Test
+        void readShouldReturnFallbackToLegacyWhenCurrentGotException() throws Exception {
+            MemoryBlobStore legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+            UnionBlobStore unionBlobStore = new UnionBlobStore(new ThrowingBlobStore(), legacyBlobStore);
+            BlobId blobId = legacyBlobStore.save(BLOB_CONTENT).get();
+
+            assertThat(unionBlobStore.read(blobId))
+                .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+        }
+
+        @Test
+        void readBytesShouldReturnFallbackToLegacyWhenCurrentGotException() throws Exception {
+            MemoryBlobStore legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+            UnionBlobStore unionBlobStore = new UnionBlobStore(new ThrowingBlobStore(), legacyBlobStore);
+            BlobId blobId = legacyBlobStore.save(BLOB_CONTENT).get();
+
+            assertThat(unionBlobStore.readBytes(blobId).get())
+                .isEqualTo(BLOB_CONTENT);
+        }
+
+    }
+
+    @Nested
+    class CurrentReadCompletesExceptionally {
+
+        @Test
+        void readShouldReturnFallbackToLegacyWhenCurrentCompletedExceptionally() throws Exception {
+            MemoryBlobStore legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+            UnionBlobStore unionBlobStore = new UnionBlobStore(new FutureThrowingBlobStore(), legacyBlobStore);
+            BlobId blobId = legacyBlobStore.save(BLOB_CONTENT).get();
+
+            assertThat(unionBlobStore.read(blobId))
+                .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+        }
+
+        @Test
+        void readBytesShouldReturnFallbackToLegacyWhenCurrentCompletedExceptionally() throws Exception {
+            MemoryBlobStore legacyBlobStore = new MemoryBlobStore(BLOB_ID_FACTORY);
+            UnionBlobStore unionBlobStore = new UnionBlobStore(new FutureThrowingBlobStore(), legacyBlobStore);
+            BlobId blobId = legacyBlobStore.save(BLOB_CONTENT).get();
+
+            assertThat(unionBlobStore.readBytes(blobId).get())
+                .isEqualTo(BLOB_CONTENT);
+        }
+    }
+
+
+    @Test
+    void readShouldReturnFromCurrentWhenAvailable() throws Exception {
+        BlobId blobId = currentBlobStore.save(BLOB_CONTENT).get();
+
+        assertThat(unionBlobStore.read(blobId))
+            .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+    }
+
+    @Test
+    void readShouldReturnFromLegacyWhenCurrentNotAvailable() throws Exception {
+        BlobId blobId = legacyBlobStore.save(BLOB_CONTENT).get();
+
+        assertThat(unionBlobStore.read(blobId))
+            .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+    }
+
+    @Test
+    void readBytesShouldReturnFromCurrentWhenAvailable() throws Exception {
+        BlobId blobId = currentBlobStore.save(BLOB_CONTENT).get();
+
+        assertThat(unionBlobStore.readBytes(blobId).get())
+            .isEqualTo(BLOB_CONTENT);
+    }
+
+    @Test
+    void readBytesShouldReturnFromLegacyWhenCurrentNotAvailable() throws Exception {
+        BlobId blobId = legacyBlobStore.save(BLOB_CONTENT).get();
+
+        assertThat(unionBlobStore.readBytes(blobId).get())
+            .isEqualTo(BLOB_CONTENT);
+    }
+
+    @Test
+    void saveShouldWriteToCurrent() throws Exception {
+        BlobId blobId = unionBlobStore.save(BLOB_CONTENT).get();
+
+        assertThat(currentBlobStore.readBytes(blobId).get())
+            .isEqualTo(BLOB_CONTENT);
+    }
+
+    @Test
+    void saveShouldNotWriteToLegacy() throws Exception {
+        BlobId blobId = unionBlobStore.save(BLOB_CONTENT).get();
+
+        assertThat(legacyBlobStore.readBytes(blobId).get())
+            .isEmpty();
+    }
+
+    @Test
+    void saveInputStreamShouldWriteToCurrent() throws Exception {
+        BlobId blobId = unionBlobStore.save(new ByteArrayInputStream(BLOB_CONTENT)).get();
+
+        assertThat(currentBlobStore.readBytes(blobId).get())
+            .isEqualTo(BLOB_CONTENT);
+    }
+
+    @Test
+    void saveInputStreamShouldNotWriteToLegacy() throws Exception {
+        BlobId blobId = unionBlobStore.save(new ByteArrayInputStream(BLOB_CONTENT)).get();
+
+        assertThat(legacyBlobStore.readBytes(blobId).get())
+            .isEmpty();
+    }
+
+    @Test
+    void streamHasContentShouldReturnTrueWhenStreamHasContent() throws Exception {
+        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(BLOB_CONTENT));
+
+        assertThat(unionBlobStore.streamHasContent(pushBackIS))
+            .isTrue();
+    }
+
+    @Test
+    void streamHasContentShouldReturnFalseWhenStreamHasNoContent() throws Exception {
+        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(new byte[0]));
+
+        assertThat(unionBlobStore.streamHasContent(pushBackIS))
+            .isFalse();
+    }
+
+    @Test
+    void streamHasContentShouldNotThrowWhenStreamHasNoContent() {
+        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(new byte[0]));
+
+        assertThatCode(() -> unionBlobStore.streamHasContent(pushBackIS))
+            .doesNotThrowAnyException();
+    }
+
+    @Test
+    void streamHasContentShouldNotDrainPushBackStreamContent() throws Exception {
+        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(BLOB_CONTENT));
+        unionBlobStore.streamHasContent(pushBackIS);
+
+        assertThat(pushBackIS)
+            .hasSameContentAs(new ByteArrayInputStream(BLOB_CONTENT));
+    }
+
+    @Test
+    void streamHasContentShouldKeepStreamEmptyWhenStreamIsEmpty() throws Exception {
+        PushbackInputStream pushBackIS = new PushbackInputStream(new ByteArrayInputStream(new byte[0]));
+        unionBlobStore.streamHasContent(pushBackIS);
+
+        assertThat(pushBackIS)
+            .hasSameContentAs(new ByteArrayInputStream(new byte[0]));
+    }
+}
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/james-project/blob/12a26f95/server/blob/pom.xml
----------------------------------------------------------------------
diff --git a/server/blob/pom.xml b/server/blob/pom.xml
index 131baa2..852d054 100644
--- a/server/blob/pom.xml
+++ b/server/blob/pom.xml
@@ -35,9 +35,9 @@
     <modules>
         <module>blob-api</module>
         <module>blob-cassandra</module>
-        <module>blob-joining</module>
         <module>blob-memory</module>
         <module>blob-objectstorage</module>
+        <module>blob-union</module>
 
         <module>mail-store</module>
     </modules>


---------------------------------------------------------------------
To unsubscribe, e-mail: server-dev-unsubscribe@james.apache.org
For additional commands, e-mail: server-dev-help@james.apache.org


Mime
View raw message