Merge pull request #18 from zapr-oss/develop

Releasing Druid Client and version bumped to 2.0

README.md

@@ -1,7 +1,7 @@
 Welcome to project Druidry!
 =======================================
 
-![build_status](https://api.travis-ci.org/zapr-oss/druidry.svg?branch=master)
+![build_status](https://api.travis-ci.org/zapr-oss/druidry.svg?branch=master) [![License: GPL v3](https://img.shields.io/badge/License-GPL%20v3-blue.svg)](https://www.gnu.org/licenses/gpl-3.0)
 
 Druid is an extremely popular tool to perform OLAP queries on event data. Druid drives real-time dashboards in most of the organisations right now. We@Zapr love Druid! Therefore we want to contribute towards making Druid, even more, friendlier to the ever expanding community. 
 
@@ -27,6 +27,12 @@ This library is still growing and does not support each and every constructs, ho
 Getting Started
 ---------------
 
+Prerequisite
+-----------
+
+* Maven
+* Java 8
+
 Usage
 -----
 
@@ -154,6 +160,19 @@ ObjectMapper mapper = new ObjectMapper();
 String requiredJson = mapper.writeValueAsString(query);
 ```
 
+``` java
+DruidConfiguration config =  DruidConfiguration
+               .builder()
+               .host("druid.io")
+               .endpoint("druid/v2/")
+               .build();
+
+DruidClient client = new DruidJerseyClient(druidConfiguration);
+client.connect();
+List<DruidResponse> responses = client.query(query, DruidResponse.class);
+client.close();
+```
+
 Supported Features
 ------------------
 

pom.xml

@@ -6,11 +6,11 @@
 
     <groupId>in.zapr.druid</groupId>
     <artifactId>druidry</artifactId>
-    <version>1.5</version>
+    <version>2.0</version>
 
-    <name>Druidry - Druid Query Generator</name>
+    <name>Druidry - Druid Java Client</name>
     <description>Druidry is an open-source Java based utility library which supports creating
-        query to Druid
+        query to Druid and connection handling with Druid
     </description>
     <url>https://github.com/zapr-oss/druidry</url>
 
@@ -23,6 +23,7 @@
         <logback.version>1.2.1</logback.version>
         <jsonassert.version>1.4.0</jsonassert.version>
         <commons.version>3.5</commons.version>
+        <jersey.version>2.26</jersey.version>
     </properties>
 
     <dependencies>
@@ -83,6 +84,30 @@
             <version>${commons.version}</version>
         </dependency>
 
+        <dependency>
+            <groupId>org.glassfish.jersey.core</groupId>
+            <artifactId>jersey-client</artifactId>
+            <version>${jersey.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.glassfish.jersey.media</groupId>
+            <artifactId>jersey-media-json-jackson</artifactId>
+            <version>${jersey.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.glassfish.jersey.inject</groupId>
+            <artifactId>jersey-hk2</artifactId>
+            <version>${jersey.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.glassfish.jersey.connectors</groupId>
+            <artifactId>jersey-apache-connector</artifactId>
+            <version>${jersey.version}</version>
+        </dependency>
+
     </dependencies>
 
     <profiles>
@@ -231,4 +256,4 @@
         </repository>
     </distributionManagement>
 
-</project>
+</project>

src/main/java/in/zapr/druid/druidry/client/DruidClient.java

@@ -0,0 +1,43 @@
+package in.zapr.druid.druidry.client;
+
+import java.util.List;
+
+import in.zapr.druid.druidry.client.exception.ConnectionException;
+import in.zapr.druid.druidry.client.exception.QueryException;
+import in.zapr.druid.druidry.query.DruidQuery;
+
+public interface DruidClient {
+
+    /**
+     * Connects with Druid
+     *
+     * @throws ConnectionException When connection is not formed
+     */
+    void connect() throws ConnectionException;
+
+    /**
+     * Closes connection with Druid
+     * @throws ConnectionException When connection is not closed
+     */
+    void close() throws ConnectionException;
+
+    /**
+     * Queries druid
+     *
+     * @param druidQuery Druid Query object
+     * @return Result from Druid
+     * @throws QueryException Error while querying
+     */
+    String query(DruidQuery druidQuery) throws QueryException;
+
+    /**
+     * Queries druid
+     *
+     * @param druidQuery Druid Query Object
+     * @param className Class according to which DruidResult should be converted to
+     * @param <T> Class according to which DruidResult should be converted to
+     * @return Druid Result in the form of class T object
+     * @throws QueryException Error while querying
+     */
+    <T> List<T> query(DruidQuery druidQuery, Class<T> className) throws QueryException;
+}

src/main/java/in/zapr/druid/druidry/client/DruidConfiguration.java

@@ -0,0 +1,104 @@
+package in.zapr.druid.druidry.client;
+
+import org.apache.commons.lang3.StringUtils;
+
+import lombok.Builder;
+import lombok.Getter;
+import lombok.Setter;
+
+@Getter
+@Setter
+public class DruidConfiguration {
+
+    private static final int DEFAULT_HTTP_PORT = 8082;
+    private static final int DEFAULT_HTTPS_PORT = 8282;
+
+    /**
+     * Protocol by which Druid Broker is accessible
+     * Defaults to HTTP
+     */
+    private DruidQueryProtocol protocol;
+
+    /**
+     * Address of Druid Broker Instance
+     */
+    private String host;
+
+    /**
+     * Port at which Druid Broker is listening.
+     * {@value DEFAULT_HTTP_PORT} if protocol is 8082
+     * {@value DEFAULT_HTTPS_PORT} if protocol is 8282
+     */
+    private Integer port;
+
+    /**
+     * Endpoint (without host address) at which query needs to be fired
+     */
+    private String endpoint;
+
+    /**
+     * Number of connections to be maintained in connection pool
+     * Is Ignored when custom JerseyConfig is passed.
+     */
+    private Integer concurrentConnectionsRequired;
+
+    @Builder
+    private DruidConfiguration(DruidQueryProtocol protocol,
+                               String host,
+                               Integer port,
+                               String endpoint,
+                               Integer concurrentConnectionsRequired) {
+
+        if (StringUtils.isEmpty(host)) {
+            throw new IllegalArgumentException("Host cannot be null or empty");
+        }
+
+        if (port != null && port < 0) {
+            throw new IllegalArgumentException("Port cannot be negative");
+        }
+
+        if (concurrentConnectionsRequired != null && concurrentConnectionsRequired < 1) {
+            throw new IllegalArgumentException("Connections required cannot be less than 1");
+        }
+
+        if (protocol == null) {
+            protocol = DruidQueryProtocol.HTTP;
+        }
+
+        if (port == null) {
+            port = getDefaultPortOnBasisOfProtocol(protocol);
+        }
+
+        this.protocol = protocol;
+        this.host = host;
+        this.port = port;
+        this.endpoint = endpoint;
+        this.concurrentConnectionsRequired = concurrentConnectionsRequired;
+    }
+
+    protected String getUrl() {
+
+        String endpoint = this.getEndpoint();
+        if (endpoint == null) {
+            endpoint = "";
+        }
+
+        return String.format("%s://%s:%d/%s",
+                this.getProtocol(),
+                this.getHost(),
+                this.getPort(),
+                endpoint);
+    }
+
+    private Integer getDefaultPortOnBasisOfProtocol(DruidQueryProtocol protocol) {
+
+        switch (protocol) {
+            case HTTP:
+                return DEFAULT_HTTP_PORT;
+            case HTTPS:
+                return DEFAULT_HTTPS_PORT;
+            default:
+                throw new IllegalArgumentException("Druid Query Protocol not handled");
+        }
+    }
+}

src/main/java/in/zapr/druid/druidry/client/DruidError.java

@@ -0,0 +1,12 @@
+package in.zapr.druid.druidry.client;
+
+import lombok.Getter;
+
+@Getter
+public class DruidError {
+
+    private String error;
+    private String errorMessage;
+    private String errorClass;
+    private String host;
+}