Add dialog UI to get Cassandra's connection info (vmware-archive#643)

Data loading from Cassandra SS tables

data/sstable/cassdb.cql

@@ -71,6 +71,50 @@ INSERT INTO users (id, name, address,
 INSERT INTO users (id, name, address,
    salary, phone) VALUES(now(),'', '',0, '');
 
+CREATE TABLE test(
+   id UUID PRIMARY KEY,
+   name text,
+   salary int,
+   text text,
+   int int,
+   boolean boolean,
+   ascii ascii,
+   inet inet,
+   timeuuid timeuuid,
+   smallint smallint,
+   tinyint tinyint,
+   varint varint,
+   bigint bigint,
+   decimal decimal,
+   double double,
+   float float,
+   time time,
+   timestamp timestamp,
+   date date,
+   duration duration,
+   blob blob
+   );
+
+INSERT INTO test (id, name, salary, text, int, boolean, ascii, inet, timeuuid, smallint,
+   tinyint, varint, bigint, decimal, double, float, time, timestamp, date, duration, blob)
+   VALUES(now(),'Mr. NULL',null, null, null, null, null, null, null, null, null, null, null, null, null,
+   null, null, null, null, null, null
+);
+
+INSERT INTO test (id, name, salary, text, int, boolean, ascii, inet, timeuuid, smallint,
+   tinyint, varint, bigint, decimal, double, float, time, timestamp, date, duration, blob)
+   VALUES(now(),'Mr. Test', 45000, null, null, true, '35', '127.0.0.1', 50554d6e-29bb-11e5-b345-feff819cdc9f,
+    1, 2, 10, toTimestamp(now()), 3.7875, 6714592679.3400884579357, 3.14753, '13:30:23.123',
+    '2017-05-05 15:00:00.000', '2020-07-14', P1DT12H30M5S, textAsBlob('adb14fbe076f6b94444c660e36a400151f26fc6f')
+);
+
+
+CREATE TABLE counter(
+   id int PRIMARY KEY,
+   counter counter
+   );
+
+UPDATE counter SET counter = counter + 1 WHERE id = 2;
 
 CREATE TABLE flights(
    ID int PRIMARY KEY,

data/sstable/loadCassandraDB.sh

@@ -15,4 +15,5 @@ ${CASSANDRA_INSTALLATION_DIR}/bin/cqlsh --file ${SAVEDIR}/cassdb.cql
 # Force Compaction to put the data into sstable
 ${CASSANDRA_INSTALLATION_DIR}/bin/nodetool flush
 ${CASSANDRA_INSTALLATION_DIR}/bin/nodetool compact cassdb
+${CASSANDRA_INSTALLATION_DIR}/bin/nodetool -h localhost -p 7199 clearsnapshot
 rm -f flights_data.csv

docs/userManual.md

@@ -26,7 +26,7 @@ one row for an airline flight.  Columns in this dataset include: the date of the
 the origin and destination cities, the origin and destination states,
 the origin airport code, the distance flown, the departure and arrival delay.
 
-Updated on 2020 Jul 30.
+Updated on 2020 Aug 05.
 
 # Contents
 |Section|Reference|
@@ -50,7 +50,8 @@ Updated on 2020 Jul 30.
 |2.3.6.|[Reading JSON files](#236-reading-json-files)|
 |2.3.7.|[Reading ORC files](#237-reading-orc-files)|
 |2.3.8.|[Reading data from SQL databases](#238-reading-data-from-sql-databases)|
-|2.3.9.|[Reading Parquet files](#239-reading-parquet-files)|
+|2.3.9.|[Reading data from Cassandra databases](#239-reading-data-from-cassandra-databases)|
+|2.3.10.|[Reading Parquet files](#2310-reading-parquet-files)|
 |2.4.|[Navigating multiple datasets](#24-navigating-multiple-datasets)|
 |3.|[Data views](#3-data-views)|
 |3.1.|[The heading of a view](#31-the-heading-of-a-view)|
@@ -214,7 +215,7 @@ storage.
   files](#236-reading-json-files).
 
 * Parquet files: allows the user to [read the data from a set of
-  Parquet files](#239-reading-parquet-files).
+  Parquet files](#2310-reading-parquet-files).
 
 * ORC files: allows the user to [read the data from a set of ORC
   files](#237-reading-orc-files).
@@ -425,7 +426,7 @@ on the local user machine.
 
 The following menu allows the user to specify the data to load.
 
-![Specifying database connections](db-menu.png)
+![Specifying database connections](db-menu-mysql.png)
 
 * database kind: A drop-down menu indicating the kind of database to
   load data from.  Currently we support 'mysql' and 'impala'.
@@ -448,7 +449,41 @@ Numeric values are converted either to integers (if they fit into
 32-bits) or to doubles.  Boolean values are read as strings
 containing two values, "true" and "false".
 
-#### 2.3.9. Reading Parquet files
+#### 2.3.9. Reading data from Cassandra databases
+
+Hillview instance is required to be running on each Cassandra node.
+Thus, Hillview must be deployed in a cluster mode with all Cassandra
+nodes listed as the workers in the config.json. Moreover, Hillview
+must have access to Cassandra's directories because each Hillview
+workers will directly read local Cassandra's SSTables. 
+
+The following menu allows the user to specify the data to load.
+
+![Specifying Cassandra database connections](db-menu-cassandra.png)
+
+* database kind: Indicating the kind of database that we will connect 
+  to, which is Cassandra. We also support another DB, 'mysql' and 
+  'impala'.
+
+* host: One of the network name/IP address of the machines hosting 
+  Cassandra cluster. Every node in Cassandra cluster are the same 
+  (no master-slave concept), thus Hillview can connect to any node.
+
+* db directory: The directory where Cassandra is located/installed.
+
+* port: The network port where Cassandra service is listening.
+
+* jmx port: The JMX port where Cassandra does inter-node communication.
+
+* database: The database/keyspace to load data from.
+
+* table: The table to load data from.
+
+* user: The name of the user connecting to the database.
+
+* password: Credentials of the user connecting to the database.
+
+#### 2.3.10. Reading Parquet files
 
 Hillview can read data from [Apache Parquet
 files](http://parquet.apache.org), a columnar storage format.  The

docs/userManual.src

@@ -357,7 +357,7 @@ on the local user machine.
 
 The following menu allows the user to specify the data to load.
 
-![Specifying database connections](db-menu.png)
+![Specifying database connections](db-menu-mysql.png)
 
 * database kind: A drop-down menu indicating the kind of database to
   load data from.  Currently we support 'mysql' and 'impala'.
@@ -380,6 +380,40 @@ Numeric values are converted either to integers (if they fit into
 32-bits) or to doubles.  Boolean values are read as strings
 containing two values, "true" and "false".
 
+#### Reading data from Cassandra databases
+
+Hillview instance is required to be running on each Cassandra node.
+Thus, Hillview must be deployed in a cluster mode with all Cassandra
+nodes listed as the workers in the config.json. Moreover, Hillview
+must have access to Cassandra's directories because each Hillview
+workers will directly read local Cassandra's SSTables. 
+
+The following menu allows the user to specify the data to load.
+
+![Specifying Cassandra database connections](db-menu-cassandra.png)
+
+* database kind: Indicating the kind of database that we will connect 
+  to, which is Cassandra. We also support another DB, 'mysql' and 
+  'impala'.
+
+* host: One of the network name/IP address of the machines hosting 
+  Cassandra cluster. Every node in Cassandra cluster are the same 
+  (no master-slave concept), thus Hillview can connect to any node.
+
+* db directory: The directory where Cassandra is located/installed.
+
+* port: The network port where Cassandra service is listening.
+
+* jmx port: The JMX port where Cassandra does inter-node communication.
+
+* database: The database/keyspace to load data from.
+
+* table: The table to load data from.
+
+* user: The name of the user connecting to the database.
+
+* password: Credentials of the user connecting to the database.
+
 #### Reading Parquet files
 
 Hillview can read data from [Apache Parquet

platform/src/main/java/org/hillview/maps/FindCassandraFilesMap.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2020 VMware Inc. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed 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.hillview.maps;
+
+import org.hillview.dataset.api.Empty;
+import org.hillview.dataset.api.IMap;
+import org.hillview.storage.CassandraConnectionInfo;
+import org.hillview.storage.CassandraDatabase;
+import org.hillview.storage.CassandraFileReference;
+import org.hillview.storage.IFileReference;
+import org.hillview.storage.CassandraDatabase.CassandraTokenRange;
+
+import javax.annotation.Nullable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class FindCassandraFilesMap implements IMap<Empty, List<IFileReference>> {
+    static final long serialVersionUID = 1;
+    private final CassandraConnectionInfo conn;
+
+    public FindCassandraFilesMap(CassandraConnectionInfo conn) {
+        this.conn = conn;
+    }
+
+    @Override
+    public List<IFileReference> apply(@Nullable Empty empty) {
+        List<IFileReference> result = new ArrayList<IFileReference>();
+        CassandraDatabase db = new CassandraDatabase(this.conn);
+        List<String> ssTables = db.getSSTablePath();
+        List<CassandraTokenRange> tokenRanges = db.getTokenRanges();
+        String localEndpoint = db.getLocalEndpoint();
+        db.closeClusterConnection();
+        for (String ssTable : ssTables)
+            result.add(new CassandraFileReference(ssTable, tokenRanges, localEndpoint));
+        return result;
+    }
+}

platform/src/main/java/org/hillview/storage/CassandraConnectionInfo.java

@@ -17,16 +17,25 @@
 
 package org.hillview.storage;
 
+/**
+ * This information is required to open a Cassandra database connection.
+ */
 public class CassandraConnectionInfo extends JdbcConnectionInformation {
     static final long serialVersionUID = 1;
 
     /** Port for establishing probe connection */
     public int jmxPort;
-    /** Local Cassandra installation directory (can be found at bin/install-cassandra.sh) */
+    /**
+     * Local Cassandra installation directory (can be found at
+     * bin/install-cassandra.sh)
+     */
     public String cassandraRootDir;
 
     @Override
     public String toString() {
-        return this.cassandraRootDir + "/" + this.port;
+        StringBuilder sb = new StringBuilder(super.toString());
+        sb.append("  jmxPort : " + this.jmxPort + "\n");
+        sb.append("  cassandraRootDir : " + this.cassandraRootDir + "\n");
+        return sb.toString();
     }
 }