[ZEPPELIN-2277] Env variable to configure maven central repo

conf/zeppelin-env.cmd.template

@@ -38,6 +38,7 @@ REM set ZEPPELIN_NOTEBOOK_S3_SSE               REM Server-side encryption enable
 REM set ZEPPELIN_IDENT_STRING   		REM A string representing this instance of zeppelin. $USER by default.
 REM set ZEPPELIN_NICENESS       		REM The scheduling priority for daemons. Defaults to 0.
 REM set ZEPPELIN_INTERPRETER_LOCALREPO         REM Local repository for interpreter's additional dependency loading
+REM set ZEPPELIN_INTERPRETER_DEP_MVNREPO       REM Maven principal repository for interpreter's additional dependency loading
 REM set ZEPPELIN_NOTEBOOK_STORAGE		REM Refers to pluggable notebook storage class, can have two classes simultaneously with a sync between them (e.g. local and remote).
 REM set ZEPPELIN_NOTEBOOK_ONE_WAY_SYNC		REM If there are multiple notebook storages, should we treat the first one as the only source of truth?
 

conf/zeppelin-env.sh.template

@@ -43,6 +43,7 @@
 # export ZEPPELIN_IDENT_STRING   		# A string representing this instance of zeppelin. $USER by default.
 # export ZEPPELIN_NICENESS       		# The scheduling priority for daemons. Defaults to 0.
 # export ZEPPELIN_INTERPRETER_LOCALREPO         # Local repository for interpreter's additional dependency loading
+# export ZEPPELIN_INTERPRETER_DEP_MVNREPO       # Remote principal repository for interpreter's additional dependency loading
 # export ZEPPELIN_NOTEBOOK_STORAGE 		# Refers to pluggable notebook storage class, can have two classes simultaneously with a sync between them (e.g. local and remote).
 # export ZEPPELIN_NOTEBOOK_ONE_WAY_SYNC	# If there are multiple notebook storages, should we treat the first one as the only source of truth?
 # export ZEPPELIN_NOTEBOOK_PUBLIC   # Make notebook public by default when created, private otherwise

conf/zeppelin-site.xml.template

@@ -239,6 +239,12 @@
   <description>Local repository for interpreter's additional dependency loading</description>
 </property>
 
+<property>
+  <name>zeppelin.interpreter.dep.mvnRepo</name>
+  <value>http://repo1.maven.org/maven2/</value>
+  <description>Remote principal repository for interpreter's additional dependency loading</description>
+</property>
+
 <property>
   <name>zeppelin.dep.localrepo</name>
   <value>local-repo</value>

docs/install/configuration.md

@@ -26,7 +26,7 @@ limitations under the License.
 ## Zeppelin Properties
 There are two locations you can configure Apache Zeppelin.
 
-* **Environment variables** can be defined `conf/zeppelin-env.sh`(`conf\zeppelin-env.cmd` for Windows). 
+* **Environment variables** can be defined `conf/zeppelin-env.sh`(`conf\zeppelin-env.cmd` for Windows).
 * **Java properties** can ba defined in `conf/zeppelin-site.xml`.
 
 If both are defined, then the **environment variables** will take priority.
@@ -255,6 +255,12 @@ If both are defined, then the **environment variables** will take priority.
     <td>interpreter</td>
     <td>Interpreter directory</td>
   </tr>
+  <tr>
+    <td><h6 class="properties">ZEPPELIN_INTERPRETER_DEP_MVNREPO</h6></td>
+    <td><h6 class="properties">zeppelin.interpreter.dep.mvnRepo</h6></td>
+    <td>http://repo1.maven.org/maven2/</td>
+    <td>Remote principal repository for interpreter's additional dependency loading</td>
+  </tr>
   <tr>
     <td><h6 class="properties">ZEPPELIN_INTERPRETER_OUTPUT_LIMIT</h6></td>
     <td><h6 class="properties">zeppelin.interpreter.output.limit</h6></td>
@@ -389,7 +395,7 @@ The following properties needs to be updated in the `zeppelin-site.xml` in order
 ### Obfuscating Passwords using the Jetty Password Tool
 
 Security best practices advise to not use plain text passwords and Jetty provides a password tool to help obfuscating the passwords used to access the KeyStore and TrustStore.
- 
+
 The Password tool documentation can be found [here](http://www.eclipse.org/jetty/documentation/current/configuring-security-secure-passwords.html).
 
 After using the tool:

zeppelin-interpreter/src/main/java/org/apache/zeppelin/dep/Booter.java

@@ -67,7 +67,15 @@ public class Booter {
   }
 
   public static RemoteRepository newCentralRepository() {
-    return new RemoteRepository("central", "default", "http://repo1.maven.org/maven2/");
+    String mvnRepo = System.getenv("ZEPPELIN_INTERPRETER_DEP_MVNREPO");
+    if (mvnRepo == null) {
+      mvnRepo = System.getProperty("zeppelin.interpreter.dep.mvnRepo");
+    }
+    if (mvnRepo == null) {
+      mvnRepo = "http://repo1.maven.org/maven2/";
+    }
+
+    return new RemoteRepository("central", "default", mvnRepo);
   }
 
   public static RemoteRepository newLocalRepository() {

zeppelin-zengine/src/main/java/org/apache/zeppelin/conf/ZeppelinConfiguration.java

@@ -108,7 +108,7 @@ public class ZeppelinConfiguration extends XMLConfiguration {
         conf = new ZeppelinConfiguration();
       }
     }
-    
+
     LOG.info("Server Host: " + conf.getServerAddress());
     if (conf.useSsl() == false) {
       LOG.info("Server Port: " + conf.getServerPort());
@@ -355,7 +355,7 @@ public class ZeppelinConfiguration extends XMLConfiguration {
   public String getNotebookDir() {
     return getString(ConfVars.ZEPPELIN_NOTEBOOK_DIR);
   }
-  
+
   public String getUser() {
     return getString(ConfVars.ZEPPELIN_NOTEBOOK_S3_USER);
   }
@@ -363,7 +363,7 @@ public class ZeppelinConfiguration extends XMLConfiguration {
   public String getBucketName() {
     return getString(ConfVars.ZEPPELIN_NOTEBOOK_S3_BUCKET);
   }
-  
+
   public String getEndpoint() {
     return getString(ConfVars.ZEPPELIN_NOTEBOOK_S3_ENDPOINT);
   }
@@ -375,7 +375,7 @@ public class ZeppelinConfiguration extends XMLConfiguration {
   public String getS3KMSKeyRegion() {
     return getString(ConfVars.ZEPPELIN_NOTEBOOK_S3_KMS_KEY_REGION);
   }
-  
+
   public String getS3EncryptionMaterialsProviderClass() {
     return getString(ConfVars.ZEPPELIN_NOTEBOOK_S3_EMP);
   }
@@ -449,6 +449,10 @@ public class ZeppelinConfiguration extends XMLConfiguration {
     return getRelativeDir(ConfVars.ZEPPELIN_INTERPRETER_LOCALREPO);
   }
 
+  public String getInterpreterMvnRepoPath() {
+    return getString(ConfVars.ZEPPELIN_INTERPRETER_DEP_MVNREPO);
+  }
+
   public String getRelativeDir(ConfVars c) {
     return getRelativeDir(getString(c));
   }
@@ -464,7 +468,7 @@ public class ZeppelinConfiguration extends XMLConfiguration {
   public boolean isWindowsPath(String path){
     return path.matches("^[A-Za-z]:\\\\.*");
   }
-  
+
   public boolean isAnonymousAllowed() {
     return getBoolean(ConfVars.ZEPPELIN_ANONYMOUS_ALLOWED);
   }
@@ -472,7 +476,7 @@ public class ZeppelinConfiguration extends XMLConfiguration {
   public boolean isNotebokPublic() {
     return getBoolean(ConfVars.ZEPPELIN_NOTEBOOK_PUBLIC);
   }
-  
+
   public String getConfDir() {
     return getString(ConfVars.ZEPPELIN_CONF_DIR);
   }
@@ -589,6 +593,8 @@ public class ZeppelinConfiguration extends XMLConfiguration {
     ZEPPELIN_INTERPRETER_JSON("zeppelin.interpreter.setting", "interpreter-setting.json"),
     ZEPPELIN_INTERPRETER_DIR("zeppelin.interpreter.dir", "interpreter"),
     ZEPPELIN_INTERPRETER_LOCALREPO("zeppelin.interpreter.localRepo", "local-repo"),
+    ZEPPELIN_INTERPRETER_DEP_MVNREPO("zeppelin.interpreter.dep.mvnRepo",
+        "http://repo1.maven.org/maven2/"),
     ZEPPELIN_INTERPRETER_CONNECT_TIMEOUT("zeppelin.interpreter.connect.timeout", 30000),
     ZEPPELIN_INTERPRETER_MAX_POOL_SIZE("zeppelin.interpreter.max.poolsize", 10),
     ZEPPELIN_INTERPRETER_GROUP_ORDER("zeppelin.interpreter.group.order", "spark,md,angular,sh,"