Add Connection module in Java/Scala API (#6)

java/pom.xml

@@ -110,9 +110,56 @@
             <scope>provided</scope>
         </dependency>
 
-    </dependencies>
+        <dependency>
+            <groupId>software.amazon.awssdk</groupId>
+            <artifactId>ssm</artifactId>
+            <version>2.10.40</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.apache.httpcomponents</groupId>
+                    <artifactId>*</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+
+        <dependency>
+            <groupId>software.amazon.awssdk</groupId>
+            <artifactId>sts</artifactId>
+            <version>2.10.40</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.apache.httpcomponents</groupId>
+                    <artifactId>*</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
 
+        <dependency>
+            <groupId>software.amazon.awssdk</groupId>
+            <artifactId>secretsmanager</artifactId>
+            <version>2.10.40</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.apache.httpcomponents</groupId>
+                    <artifactId>*</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
 
+        <dependency>
+            <groupId>io.specto</groupId>
+            <artifactId>hoverfly-java</artifactId>
+            <version>0.12.2</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
 
     <build>
         <plugins>

java/src/main/java/com/logicalclocks/featurestore/FeatureStore.java

@@ -1,5 +1,6 @@
 package com.logicalclocks.featurestore;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
 import com.google.common.base.Strings;
 import com.logicalclocks.featurestore.engine.SparkEngine;
 import com.logicalclocks.featurestore.metadata.FeatureGroupApi;
@@ -13,9 +14,11 @@
 public class FeatureStore {
 
   @Getter @Setter
+  @JsonProperty("featurestoreId")
   private Integer id;
 
   @Getter @Setter
+  @JsonProperty("featurestoreName")
   private String name;
 
   @Getter @Setter
@@ -45,4 +48,14 @@ public FeatureGroup getFeatureGroup(String name, Integer version)
   public Dataset<Row> sql(String query) {
     return SparkEngine.getInstance().sql(query);
   }
+
+  @Override
+  public String toString() {
+    return "FeatureStore{" +
+        "id=" + id +
+        ", name='" + name + '\'' +
+        ", projectId=" + projectId +
+        ", featureGroupApi=" + featureGroupApi +
+        '}';
+  }
 }

java/src/main/java/com/logicalclocks/featurestore/FsQuery.java

@@ -0,0 +1,15 @@
+package com.logicalclocks.featurestore;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@JsonIgnoreProperties(ignoreUnknown = true)
+@AllArgsConstructor
+@NoArgsConstructor
+public class FsQuery {
+  @Getter @Setter
+  private String query;
+}

java/src/main/java/com/logicalclocks/featurestore/HopsworksConnection.java

@@ -0,0 +1,112 @@
+package com.logicalclocks.featurestore;
+
+import com.google.common.base.Strings;
+import com.logicalclocks.featurestore.metadata.FeatureStoreApi;
+import com.logicalclocks.featurestore.metadata.HopsworksClient;
+import com.logicalclocks.featurestore.metadata.ProjectApi;
+import com.logicalclocks.featurestore.util.Constants;
+import lombok.Builder;
+import lombok.Getter;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import software.amazon.awssdk.regions.Region;
+
+import java.io.Closeable;
+import java.io.IOException;
+
+public class HopsworksConnection implements Closeable {
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(HopsworksConnection.class);
+
+  @Getter
+  private String host;
+
+  @Getter
+  private int port;
+
+  @Getter
+  private String project;
+
+  @Getter
+  private Region region;
+
+  @Getter
+  private SecretStore secretStore;
+
+  @Getter
+  private boolean hostnameVerification;
+
+  @Getter
+  private String trustStorePath;
+
+  @Getter
+  private String certPath;
+
+  @Getter
+  private String APIKeyFilePath;
+
+
+  private FeatureStoreApi featureStoreApi = new FeatureStoreApi();
+  private ProjectApi projectApi = new ProjectApi();
+
+  private Project projectObj;
+
+  @Builder
+  public HopsworksConnection(String host, int port, String project, Region region, SecretStore secretStore,
+                             boolean hostnameVerification, String trustStorePath,
+                             String certPath, String APIKeyFilePath) throws IOException, FeatureStoreException {
+    this.host = host;
+    this.port = port;
+    this.project = project;
+    this.region = region;
+    this.secretStore = secretStore;
+    this.hostnameVerification = hostnameVerification;
+    this.trustStorePath = trustStorePath;
+    this.certPath = certPath;
+    this.APIKeyFilePath = APIKeyFilePath;
+
+    HopsworksClient hopsworksClient = HopsworksClient.setupHopsworksClient(host, port, region, secretStore,
+        hostnameVerification, trustStorePath, APIKeyFilePath);
+    projectObj = getProject();
+    hopsworksClient.downloadCredentials(projectObj, certPath);
+  }
+
+  /**
+   * Retrieve the project feature store
+   * @return
+   * @throws IOException
+   * @throws FeatureStoreException
+   */
+  public FeatureStore getFeatureStore() throws IOException, FeatureStoreException{
+    return getFeatureStore(project + Constants.FEATURESTORE_SUFFIX);
+  }
+
+  /**
+   * Retrieve a feature store based on name. The feature store needs to be shared with
+   * the connection's project.
+   * @param name
+   * @return
+   * @throws IOException
+   * @throws FeatureStoreException
+   */
+  public FeatureStore getFeatureStore(String name) throws IOException, FeatureStoreException {
+    return featureStoreApi.get(projectObj.getProjectId(), name);
+  }
+
+  /**
+   * Close the connection and clean up the certificates.
+   */
+  public void close() {
+    // Close the client
+  }
+
+  private Project getProject() throws IOException, FeatureStoreException {
+    if (Strings.isNullOrEmpty(project)) {
+      // User didn't specify a project in the connection construction. Assume they are running
+      // from within Hopsworks and the project name is available a system property
+      project = System.getProperty(Constants.PROJECTNAME_ENV);
+    }
+    LOGGER.info("Getting information for project name: " + project);
+    return projectApi.get(project);
+  }
+}

java/src/main/java/com/logicalclocks/featurestore/MainClass.java

@@ -9,11 +9,14 @@ public class MainClass {
   private final static Logger LOGGER = LoggerFactory.getLogger(MainClass.class);
 
   public static void main(String[] args) throws Exception {
-    FeatureStore fs = new FeatureStore();
-    fs.setProjectId(120);
-    fs.setId(67);
+
+    HopsworksConnection connection = HopsworksConnection.builder().build();
+
+    FeatureStore fs = connection.getFeatureStore();
+    LOGGER.info("Feature Store " + fs);
 
     FeatureGroup fg = fs.getFeatureGroup("attendances_features", 1);
+
     LOGGER.info("Name " + fg.getName());
 
     LOGGER.info("Brace yourself, I'm running the query");

java/src/main/java/com/logicalclocks/featurestore/Project.java

@@ -0,0 +1,20 @@
+package com.logicalclocks.featurestore;
+
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@NoArgsConstructor
+public class Project {
+
+  @Getter @Setter
+  private Integer projectId;
+  @Getter @Setter
+  private String projectName;
+  @Getter @Setter
+  private String owner;
+
+  public Project(Integer projectId) {
+    this.projectId = projectId;
+  }
+}

java/src/main/java/com/logicalclocks/featurestore/SecretStore.java

@@ -0,0 +1,6 @@
+package com.logicalclocks.featurestore;
+
+public enum SecretStore {
+  PARAMETER_STORE,
+  SECRET_MANAGER
+}

java/src/main/java/com/logicalclocks/featurestore/metadata/AuthorizationHandler.java

@@ -0,0 +1,34 @@
+package com.logicalclocks.featurestore.metadata;
+
+import org.apache.http.HttpResponse;
+import org.apache.http.HttpStatus;
+import org.apache.http.client.ClientProtocolException;
+import org.apache.http.client.ResponseHandler;
+import org.apache.http.util.EntityUtils;
+
+import java.io.IOException;
+import java.nio.charset.Charset;
+
+public class AuthorizationHandler<T> implements ResponseHandler<T> {
+
+  private ResponseHandler<T> originalResponseHandler;
+
+  AuthorizationHandler(ResponseHandler<T> originalResponseHandler) {
+    this.originalResponseHandler = originalResponseHandler;
+  }
+
+  @Override
+  public T handleResponse(HttpResponse response) throws ClientProtocolException, IOException {
+    if (response.getStatusLine().getStatusCode() == HttpStatus.SC_UNAUTHORIZED) {
+      throw new UnauthorizedException();
+    } else if (response.getStatusLine().getStatusCode() / 100 == 4) {
+      throw new IOException("Error: " + response.getStatusLine().getStatusCode() +
+          EntityUtils.toString(response.getEntity(), Charset.defaultCharset()));
+    } else if (response.getStatusLine().getStatusCode() / 100 == 5) {
+      // TODO(fabio): Propagate http error upstream
+      throw new InternalException();
+    }
+
+    return originalResponseHandler.handleResponse(response);
+  }
+}

java/src/main/java/com/logicalclocks/featurestore/metadata/Credentials.java

@@ -0,0 +1,18 @@
+package com.logicalclocks.featurestore.metadata;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@NoArgsConstructor
+@AllArgsConstructor
+public class Credentials {
+
+  @Getter @Setter
+  private String kStore;
+  @Getter @Setter
+  private String tStore;
+  @Getter @Setter
+  private String password;
+}

java/src/main/java/com/logicalclocks/featurestore/metadata/FeatureGroupApi.java

@@ -18,15 +18,12 @@ public class FeatureGroupApi {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(FeatureGroupApi.class);
 
-  private HopsworksClient hopsworksClient;
-
-  public FeatureGroupApi() throws FeatureStoreException {
-    hopsworksClient = HopsworksClient.getInstance();
-  }
+  public FeatureGroupApi() throws FeatureStoreException { }
 
   public FeatureGroup get(FeatureStore featureStore, String fgName, Integer fgVersion)
       throws IOException, FeatureStoreException {
-   String pathTemplate = HopsworksClient.PROJECT_PATH
+    HopsworksClient hopsworksClient = HopsworksClient.getInstance();
+    String pathTemplate = HopsworksClient.PROJECT_PATH
         + FeatureStoreApi.FEATURE_STORE_PATH
         + FEATURE_GROUP_PATH;
 

java/src/main/java/com/logicalclocks/featurestore/metadata/FeatureStoreApi.java

@@ -1,8 +1,33 @@
 package com.logicalclocks.featurestore.metadata;
 
+import com.damnhandy.uri.template.UriTemplate;
+import com.logicalclocks.featurestore.FeatureStore;
+import com.logicalclocks.featurestore.FeatureStoreException;
+import org.apache.http.client.methods.HttpGet;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+
 public class FeatureStoreApi {
 
   public static final String FEATURE_STORE_SERVICE_PATH = "/featurestores";
   public static final String FEATURE_STORE_PATH =  FEATURE_STORE_SERVICE_PATH + "{/fsId}";
+  public static final String FEATURE_STORE_NAME_PATH =  FEATURE_STORE_SERVICE_PATH + "{/fsName}";
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(FeatureStoreApi.class);
+
+  public FeatureStore get(int projectId, String name) throws IOException, FeatureStoreException {
+    HopsworksClient hopsworksClient = HopsworksClient.getInstance();
+    String pathTemplate = HopsworksClient.PROJECT_PATH
+        + FEATURE_STORE_NAME_PATH;
+
+    String uri = UriTemplate.fromTemplate(pathTemplate)
+        .set("projectId", projectId)
+        .set("fsName", name)
+        .expand();
 
+    LOGGER.info("Sending metadata request: " + uri);
+    return hopsworksClient.handleRequest(new HttpGet(uri), FeatureStore.class);
+  }
 }