Updated Dropwizard sample to support Dropbox as file storage via it's API

Author: oleksii-unnamed

Demos/Dropwizard/configuration.yml

@@ -54,7 +54,7 @@ common:
 ################################################
 comparison:
   # Files provider, where to get files to show them in browse dialog
-  # Available values are `google` - using Google Drive API, `local` - using local directories
+  # Available values are `google` - using Google Drive API, `dropbox` - using Dropbox API, `local` - using local directories
   filesProviderType: ${FILES_PROVIDER_TYPE:-local}
   # Result pages preload
   # How many pages from a result document should be loaded, remaining pages will be loaded on page scrolling
@@ -101,4 +101,14 @@ google:
   # Default value is `8888`
   localServerReceiverPort: ${LOCAL_SERVER_RECEIVER_PORT:-8888}
   # user ID or null if not using a persisted credential store
-  authorizationUserId: user
+  authorizationUserId: user
+################################################
+# Dropbox API files provider Configuration
+################################################
+dropbox:
+  # The identifier that will be used as User-Agent in API requests
+  clientIdentifier: ${CLIENT_IDENTIFIER:groupdocs/comparison-java}
+  # Dropbox access token
+  accessToken: ${ACCESS_TOKEN:-}
+  # Directory in which result files will be uploaded via Dropbox API, default value is `ResultFiles`.
+  resultDirectory: ${RESULT_DIR:-ResultFiles}

Demos/Dropwizard/pom.xml

@@ -13,6 +13,9 @@
     <url>https://groupdocs.com</url>
 
     <properties>
+        <java.version>15</java.version>
+        <maven.compiler.source>${java.version}</maven.compiler.source>
+        <maven.compiler.target>${java.version}</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
 
@@ -21,7 +24,7 @@
             <groupId>io.dropwizard</groupId>
             <artifactId>dropwizard-core</artifactId>
             <version>2.0.28</version>
-        </dependency>        
+        </dependency>
         <dependency>
             <groupId>io.dropwizard</groupId>
             <artifactId>dropwizard-views-freemarker</artifactId>
@@ -85,6 +88,16 @@
             <artifactId>jaxb-api</artifactId>
             <version>2.3.0</version>
         </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>2.13.3</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-annotations</artifactId>
+            <version>2.13.3</version>
+        </dependency>
         <dependency>
             <groupId>javax.activation</groupId>
             <artifactId>activation</artifactId>
@@ -108,6 +121,13 @@
             <version>1.32.1</version>
         </dependency>
 
+        <!-- Dropbox API -->
+        <dependency>
+            <groupId>com.dropbox.core</groupId>
+            <artifactId>dropbox-core-sdk</artifactId>
+            <version>5.2.0</version>
+        </dependency>
+
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
@@ -122,10 +142,6 @@
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.0</version>
-                <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
-                </configuration>
             </plugin>
             <plugin>
                 <groupId>org.codehaus.mojo</groupId>

Demos/Dropwizard/src/main/java/com/groupdocs/ui/common/Defaults.java

@@ -8,7 +8,7 @@ interface Application {
 
     interface Comparison {
         enum FilesProviderType {
-            LOCAL, GOOGLE
+            LOCAL, GOOGLE, DROPBOX
         }
 
         int DEFAULT_PRELOAD_RESULT_PAGE_COUNT = 2;

Demos/Dropwizard/src/main/java/com/groupdocs/ui/common/MainService.java

@@ -5,6 +5,7 @@
 import com.groupdocs.ui.common.config.GlobalConfiguration;
 import com.groupdocs.ui.common.exception.TotalGroupDocsExceptionMapper;
 import com.groupdocs.ui.common.health.TemplateHealthCheck;
+import com.groupdocs.ui.common.util.TempFilesManager;
 import com.groupdocs.ui.comparison.resources.ComparisonResources;
 import io.dropwizard.Application;
 import io.dropwizard.assets.AssetsBundle;
@@ -125,6 +126,8 @@ public void run(GlobalConfiguration globalConfiguration, Environment environment
 
         final CommonConfiguration commonConfiguration = globalConfiguration.getCommon();
 
+        TempFilesManager.createInstance(globalConfiguration.getComparison().getTempDirectory());
+
         final SessionHandler sessionHandler = new SessionHandler();
         sessionHandler.setMaxInactiveInterval(commonConfiguration.getSessionTimeout());
         sessionHandler.addEventListener(comparisonResources);

Demos/Dropwizard/src/main/java/com/groupdocs/ui/common/config/GlobalConfiguration.java

@@ -2,6 +2,7 @@
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.groupdocs.ui.comparison.config.ComparisonConfiguration;
+import com.groupdocs.ui.comparison.config.DropboxProviderConfiguration;
 import com.groupdocs.ui.comparison.config.GoogleProviderConfiguration;
 import com.groupdocs.ui.comparison.config.LocalProviderConfiguration;
 import io.dropwizard.Configuration;
@@ -40,6 +41,10 @@ public class GlobalConfiguration extends Configuration {
     @JsonProperty
     private GoogleProviderConfiguration google;
 
+    @Valid
+    @JsonProperty
+    private DropboxProviderConfiguration dropbox;
+
     /**
      * Constructor
      */
@@ -50,6 +55,7 @@ public GlobalConfiguration() {
         comparison = new ComparisonConfiguration();
         local = new LocalProviderConfiguration();
         google = new GoogleProviderConfiguration();
+        dropbox = new DropboxProviderConfiguration();
     }
 
     /**
@@ -88,6 +94,15 @@ public ComparisonConfiguration getComparison() {
         return comparison;
     }
 
+    /**
+     * Get local provider configuration
+     *
+     * @return local provider configuration
+     */
+    public LocalProviderConfiguration getLocal() {
+        return local;
+    }
+
     /**
      * Get google provider configuration
      *
@@ -98,12 +113,12 @@ public GoogleProviderConfiguration getGoogle() {
     }
 
     /**
-     * Get local provider configuration
+     * Get dropbox provider configuration
      *
-     * @return local provider configuration
+     * @return dropbox provider configuration
      */
-    public LocalProviderConfiguration getLocal() {
-        return local;
+    public DropboxProviderConfiguration getDropbox() {
+        return dropbox;
     }
 }
 

Demos/Dropwizard/src/main/java/com/groupdocs/ui/common/exception/ApiException.java

@@ -0,0 +1,26 @@
+package com.groupdocs.ui.common.exception;
+
+/**
+ * The type Api exception.
+ */
+public class ApiException extends TotalGroupDocsException {
+
+    /**
+     * Instantiates a new Api exception.
+     *
+     * @param message the message
+     */
+    public ApiException(String message) {
+        super(message);
+    }
+
+    /**
+     * Instantiates a new Api exception.
+     *
+     * @param message the message
+     * @param cause   the cause
+     */
+    public ApiException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

Demos/Dropwizard/src/main/java/com/groupdocs/ui/common/exception/LocalDiskException.java

@@ -0,0 +1,26 @@
+package com.groupdocs.ui.common.exception;
+
+/**
+ * The type Api exception.
+ */
+public class LocalDiskException extends TotalGroupDocsException {
+
+    /**
+     * Instantiates a new Api exception.
+     *
+     * @param message the message
+     */
+    public LocalDiskException(String message) {
+        super(message);
+    }
+
+    /**
+     * Instantiates a new Api exception.
+     *
+     * @param message the message
+     * @param cause   the cause
+     */
+    public LocalDiskException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

Demos/Dropwizard/src/main/java/com/groupdocs/ui/common/util/TempFilesManager.java

@@ -0,0 +1,50 @@
+package com.groupdocs.ui.common.util;
+
+import com.groupdocs.ui.common.exception.TotalGroupDocsException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.nio.file.FileSystems;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+public final class TempFilesManager {
+    private static final Logger logger = LoggerFactory.getLogger(TempFilesManager.class);
+    private static TempFilesManager INSTANCE;
+    private final Path tempDirectoryAbsolutePath;
+
+    private TempFilesManager(Path tempDirectory) {
+        final boolean isRelative = !tempDirectory.isAbsolute();
+        if (isRelative) {
+            tempDirectory = FileSystems.getDefault().getPath(tempDirectory.toString()).toAbsolutePath();
+        }
+        logger.debug("Temp directory is going to be '" + tempDirectory + "', creating it...");
+        Path createdTempDirectory = tempDirectory;
+        try {
+            if (Files.notExists(tempDirectory)) {
+                createdTempDirectory = Files.createDirectories(tempDirectory);
+            }
+        } catch (IOException e) {
+            logger.error("Exception throws while creating temp directory: '" + tempDirectory + "'");
+            throw new TotalGroupDocsException("Can't access temp directory", e);
+        }
+        this.tempDirectoryAbsolutePath = createdTempDirectory.toAbsolutePath();
+    }
+
+    public static void createInstance(String tempDirectory) {
+        if (tempDirectory == null) {
+            throw new IllegalArgumentException("tempDirectory must not be null");
+        }
+        INSTANCE = new TempFilesManager(Path.of(tempDirectory));
+    }
+
+    public static TempFilesManager getInstance() {
+        return INSTANCE;
+    }
+
+    public java.nio.file.Path createTempPath(String fileName) {
+
+        return tempDirectoryAbsolutePath.resolve(fileName);
+    }
+}

Demos/Dropwizard/src/main/java/com/groupdocs/ui/comparison/config/DropboxProviderConfiguration.java

@@ -0,0 +1,88 @@
+package com.groupdocs.ui.comparison.config;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import io.dropwizard.Configuration;
+import org.apache.commons.lang3.StringUtils;
+
+import javax.validation.Valid;
+
+/**
+ * The type Dropbox provider configuration.
+ */
+public class DropboxProviderConfiguration extends Configuration {
+
+    @Valid
+    @JsonProperty
+    private String clientIdentifier;
+
+    @Valid
+    @JsonProperty
+    private String accessToken;
+
+    @Valid
+    @JsonProperty
+    private String resultDirectory;
+
+    /**
+     * The identifier that will be used as User-Agent in API requests
+     *
+     * @return The identifier
+     */
+    public String getClientIdentifier() {
+        return StringUtils.isBlank(clientIdentifier) ? "groupdocs/comparison-java" : clientIdentifier;
+    }
+
+    /**
+     * The identifier that will be used as User-Agent in API requests
+     *
+     * @param clientIdentifier The identifier
+     */
+    public void setClientIdentifier(String clientIdentifier) {
+        this.clientIdentifier = clientIdentifier;
+    }
+
+    /**
+     * Dropbox access token
+     *
+     * @return access token
+     */
+    public String getAccessToken() {
+        return accessToken;
+    }
+
+    /**
+     * Dropbox access token
+     *
+     * @param accessToken access token
+     */
+    public void setAccessToken(String accessToken) {
+        this.accessToken = accessToken;
+    }
+
+    /**
+     * Directory in which result files will be uploaded via Dropbox API, default value is `ResultFiles`.
+     *
+     * @return the result directory
+     */
+    public String getResultDirectory() {
+        return StringUtils.isBlank(resultDirectory) ? "ResultFiles" : resultDirectory;
+    }
+
+    /**
+     * Directory in which result files will be uploaded via Dropbox API, default value is `ResultFiles`.
+     *
+     * @param resultDirectory the result directory
+     */
+    public void setResultDirectory(String resultDirectory) {
+        this.resultDirectory = resultDirectory;
+    }
+
+    @Override
+    public String toString() {
+        return "DropboxProviderConfiguration{" +
+                "clientIdentifier='" + getClientIdentifier() + '\'' +
+                ", accessToken='" + getAccessToken() + '\'' +
+                ", resultDirectory='" + getResultDirectory() + '\'' +
+                '}';
+    }
+}