add isolation level to oracle plugin

Author: jster1357

oracle-plugin/docs/Oracle-batchsink.md

@@ -30,6 +30,11 @@ You also can use the macro function ${conn(connection-name)}.
 
 **Role** Login role of the user when connecting to the database. For eg, NORMAL, SYSDBA, SYSOPER, etc.
 
+**Transaction Isolation Level** The transaction isolation level of the databse connection
+- TRANSACTION_READ_COMMITTED: No dirty reads. Non-repeatable reads and phantom reads are possible.
+- TRANSACTION_SERIALIZABLE (default): No dirty reads. Non-repeatable and phantom reads are prevented.
+- Note: If the user role selected is SYSDBA or SYSOPER, the plugin will default to TRANSACTION_READ_COMMITTED to prevent ORA-08178 errors
+
 **Connection Type** Whether to use an SID or Service Name when connecting to the database.
 
 **SID/Service Name/TNS Connect Descriptor:** Oracle connection point (Database name, Service name, or a TNS Connect Descriptor). When using TNS, place

oracle-plugin/docs/Oracle-batchsource.md

@@ -38,6 +38,11 @@ the full TNS Connect Descriptor in the text field. For example:
 
 **Role** Login role of the user when connecting to the database.
 
+**Transaction Isolation Level** The transaction isolation level of the databse connection
+- TRANSACTION_READ_COMMITTED: No dirty reads. Non-repeatable reads and phantom reads are possible.
+- TRANSACTION_SERIALIZABLE (default): No dirty reads. Non-repeatable and phantom reads are prevented.
+- Note: If the user role selected is SYSDBA or SYSOPER, the plugin will default to TRANSACTION_READ_COMMITTED to prevent ORA-08178 errors
+
 **Import Query:** The SELECT query to use to import data from the specified table.
 You can specify an arbitrary number of columns to import, or import all columns using \*. The Query should
 contain the '$CONDITIONS' string. For example, 'SELECT * FROM table WHERE $CONDITIONS'.

oracle-plugin/docs/Oracle-connector.md

@@ -31,6 +31,11 @@ the full TNS Connect Descriptor in the text field. For example:
 
 **Role:** Login role of the user when connecting to the database.
 
+**Transaction Isolation Level** The transaction isolation level of the databse connection
+- TRANSACTION_READ_COMMITTED: No dirty reads. Non-repeatable reads and phantom reads are possible.
+- TRANSACTION_SERIALIZABLE (default): No dirty reads. Non-repeatable and phantom reads are prevented.
+- Note: If the user role selected is SYSDBA or SYSOPER, the plugin will default to TRANSACTION_READ_COMMITTED to prevent ORA-08178 errors
+
 **Connection Arguments:** A list of arbitrary string tag/value pairs as connection arguments. These arguments
 will be passed to the JDBC driver, as connection arguments, for JDBC drivers that may need additional configurations.
 This is a semicolon-separated list of key-value pairs, where each pair is separated by a equals '=' and specifies

oracle-plugin/src/main/java/io/cdap/plugin/oracle/OracleConnectorConfig.java

@@ -79,6 +79,12 @@ public String getConnectionString() {
   @Macro
   private String database;
 
+  @Name(OracleConstants.TRANSACTION_ISOLATION_LEVEL)
+  @Description("The transaction isolation level for the database session.")
+  @Macro
+  @Nullable
+  private String transactionIsolationLevel;
+
   @Override
   protected int getDefaultPort() {
     return 1521;
@@ -105,10 +111,17 @@ public Properties getConnectionArgumentsProperties() {
     prop.put(INTERNAL_LOGON_PROPERTY, getRole());
     return prop;
   }
-  
+
   public String getTransactionIsolationLevel() {
-    return ROLE_NORMAL.equals(getRole()) ? null :
-      TransactionIsolationLevel.Level.TRANSACTION_READ_COMMITTED.name();
+    //if null default to the highest isolation level possible
+    if (transactionIsolationLevel == null) {
+      transactionIsolationLevel = TransactionIsolationLevel.Level.TRANSACTION_SERIALIZABLE.name();
+    }
+    //To solve the problem of ORA-08178: illegal SERIALIZABLE clause specified for user INTERNAL
+    //This ensures that the role is mapped to the right serialization level, even w/ incorrect user input
+    //if role is SYSDBA or SYSOP it will map to read_committed. else serialized
+    return (!getRole().equals(ROLE_NORMAL)) ? TransactionIsolationLevel.Level.TRANSACTION_READ_COMMITTED.name() :
+            TransactionIsolationLevel.Level.valueOf(transactionIsolationLevel).name();
   }
 
   @Override

oracle-plugin/src/main/java/io/cdap/plugin/oracle/OracleConstants.java

@@ -35,4 +35,5 @@ private OracleConstants() {
   public static final String ROLE = "role";
   public static final String NAME_DATABASE = "database";
   public static final String TNS_CONNECTION_TYPE = "TNS";
+  public static final String TRANSACTION_ISOLATION_LEVEL = "transactionIsolationLevel";
 }

oracle-plugin/src/main/java/io/cdap/plugin/oracle/OracleSource.java

@@ -78,6 +78,7 @@ public static class OracleSourceConfig extends AbstractDBSpecificSourceConfig {
     @Nullable
     @Description("Whether to use an existing connection.")
     private Boolean useConnection;
+
     @Name(NAME_CONNECTION)
     @Macro
     @Nullable
@@ -130,7 +131,7 @@ public void validate(FailureCollector collector) {
 
     @Override
     public String getTransactionIsolationLevel() {
-      return getConnection().getTransactionIsolationLevel();
+      return connection.getTransactionIsolationLevel();
     }
   }
 

oracle-plugin/widgets/Oracle-batchsink.json

@@ -88,6 +88,18 @@
             ]
           }
         },
+        {
+          "widget-type": "select",
+          "label": "Transaction Isolation Level",
+          "name": "transactionIsolationLevel",
+          "widget-attributes": {
+            "values": [
+              "TRANSACTION_READ_COMMITTED",
+              "TRANSACTION_SERIALIZABLE"
+            ],
+            "default": "TRANSACTION_SERIALIZABLE"
+          }
+        },
         {
           "name": "connectionType",
           "label": "Connection Type",
@@ -179,6 +191,18 @@
   ],
   "outputs": [],
   "filters": [
+    {
+      "name": "showIsolationLevels",
+      "condition": {
+        "expression": "role  == 'normal'"
+      },
+      "show": [
+        {
+          "type": "property",
+          "name": "transactionIsolationLevel"
+        }
+      ]
+    },
     {
       "name": "showConnectionProperties ",
       "condition": {
@@ -220,6 +244,10 @@
         {
           "type": "property",
           "name": "database"
+        },
+        {
+          "type": "property",
+          "name": "transactionIsolationLevel"
         }
       ]
     },

oracle-plugin/widgets/Oracle-batchsource.json

@@ -88,6 +88,18 @@
             ]
           }
         },
+        {
+          "widget-type": "select",
+          "label": "Transaction Isolation Level",
+          "name": "transactionIsolationLevel",
+          "widget-attributes": {
+            "values": [
+              "TRANSACTION_READ_COMMITTED",
+              "TRANSACTION_SERIALIZABLE"
+            ],
+            "default": "TRANSACTION_SERIALIZABLE"
+          }
+        },
         {
           "name": "connectionType",
           "label": "Connection Type",
@@ -237,6 +249,18 @@
     }
   ],
   "filters": [
+    {
+      "name": "showIsolationLevels",
+      "condition": {
+        "expression": "role == 'normal'"
+      },
+      "show": [
+        {
+          "type": "property",
+          "name": "transactionIsolationLevel"
+        }
+      ]
+    },
     {
       "name": "showConnectionProperties ",
       "condition": {
@@ -278,6 +302,10 @@
         {
           "type": "property",
           "name": "database"
+        },
+        {
+          "type": "property",
+          "name": "transactionIsolationLevel"
         }
       ]
     },

oracle-plugin/widgets/Oracle-connector.json

@@ -97,6 +97,18 @@
               }
             ]
           }
+        },
+        {
+          "widget-type": "select",
+          "label": "Transaction Isolation Level",
+          "name": "transactionIsolationLevel",
+          "widget-attributes": {
+            "values": [
+              "TRANSACTION_READ_COMMITTED",
+              "TRANSACTION_SERIALIZABLE"
+            ],
+            "default": "TRANSACTION_SERIALIZABLE"
+          }
         }
       ]
     },
@@ -118,5 +130,19 @@
       ]
     }
   ],
+  "filters" : [
+    {
+      "name": "showIsolationLevels",
+      "condition": {
+        "expression": "role  == 'normal'"
+      },
+      "show": [
+        {
+          "type": "property",
+          "name": "transactionIsolationLevel"
+        }
+      ]
+    }
+  ],
   "outputs": []
 }