feat: Ability to pass in odbc connection to transport

lib/Connection.js

@@ -23,6 +23,7 @@ const availableTransports = {
  * @property {string} [ipc=*NA] - The key name/security route to XMLSERVICE job. Default is ``*NA``.
  * @property {string} [ctl=*here] - The control options for XMLSERVICE jobs. Default is ``*here``.
  * @property {string} [xslib=QXMLSERV] - The XMLSERVICE library. Default is ``QXMLSERV``.
+ * @property {object} [odbcConnection] - An existing odbc connection already connected to the db.
  */
 
 /**

lib/transports/odbcTransport.js

@@ -13,6 +13,62 @@ try {
   }
 }
 
+/**
+ * Function to call xmlservice regardless if an existing connection was passed
+ * @private
+ * @param {Object} parameters - Arguments to call xml service procedure
+ */
+function callXmlService(parameters) {
+  const {
+    connection,
+    sql,
+    queryParameters,
+    done,
+    shouldCloseConnection,
+    verbose,
+  } = parameters;
+
+  if (verbose) {
+    console.log(`SQL to run is ${sql}`);
+  }
+
+  connection.query(sql, queryParameters, (queryError, results) => {
+    if (queryError) {
+      done(queryError, null);
+      return;
+    }
+    let xmlOutput = '';
+
+    if (!results) {
+      done('Empty result set was returned', null);
+      return;
+    }
+
+    results.forEach((chunk) => {
+      xmlOutput += chunk.OUT151;
+    });
+
+    if (shouldCloseConnection) {
+      connection.close((closeError) => {
+        if (closeError) {
+          done(closeError, null);
+          return;
+        }
+        done(null, xmlOutput);
+      });
+    } else {
+      done(null, xmlOutput);
+    }
+  });
+}
+
+/**
+ * @private
+ * @param {object} config - Configuration options for odbc transport
+ * @param {string} xmlIn - The xml input to run with xml service
+ * @param {function} done - User defined callback to invoke when completed
+ */
+
 function odbcCall(config, xmlInput, done) {
   // odbc transport is not available bail out
   if (odbc === null) {
@@ -28,59 +84,45 @@ function odbcCall(config, xmlInput, done) {
     xslib = 'QXMLSERV',
     verbose = false,
     dsn = null,
+    odbcConnection = null,
   } = config;
 
   const sql = `call ${xslib}.iPLUGR512K(?,?,?)`;
-  const driver = 'IBM i Access ODBC Driver';
-  let connectionString;
+  const queryParameters = [ipc, ctl, xmlInput];
+  const parameters = {
+    sql, queryParameters, done, verbose, shouldCloseConnection: !odbcConnection,
+  };
 
-  if (dsn && typeof dsn === 'string') {
-    connectionString = `DSN=${dsn}`;
-  } else {
-    connectionString = `DRIVER=${driver};SYSTEM=${host};`;
+  if (!odbcConnection) { // get a connection then call xml service
+    // generate connection string
+    let connectionString;
 
-    if (username && typeof username === 'string') {
-      connectionString += `UID=${username};`;
-    }
-    if (password && typeof password === 'string') {
-      connectionString += `PWD=${password};`;
-    }
-  }
-
-  if (verbose) {
-    console.log(`SQL to run is ${sql}`);
-  }
+    if (dsn && typeof dsn === 'string') {
+      connectionString = `DSN=${dsn}`;
+    } else {
+      connectionString = `DRIVER=IBM i Access ODBC Driver;SYSTEM=${host};`;
 
-  odbc.connect(connectionString, (connectError, connection) => {
-    if (connectError) {
-      done(connectError, null);
-      return;
+      if (username && typeof username === 'string') {
+        connectionString += `UID=${username};`;
+      }
+      if (password && typeof password === 'string') {
+        connectionString += `PWD=${password};`;
+      }
     }
-    connection.query(sql, [ipc, ctl, xmlInput], (queryError, results) => {
-      if (queryError) {
-        done(queryError, null);
+
+    // connect and call xmlservice
+    odbc.connect(connectionString, (connectError, connection) => {
+      if (connectError) {
+        done(connectError, null);
         return;
       }
-      connection.close((closeError) => {
-        if (closeError) {
-          done(closeError, null);
-          return;
-        }
-
-        if (!results) {
-          done('Empty result set was returned', null);
-          return;
-        }
-
-        let xmlOutput = '';
-
-        results.forEach((chunk) => {
-          xmlOutput += chunk.OUT151;
-        });
-        done(null, xmlOutput);
-      });
+      parameters.connection = connection;
+      callXmlService(parameters);
     });
-  });
+  } else { // passed in connection should already be connected
+    parameters.connection = odbcConnection;
+    callXmlService(parameters);
+  }
 }
 
 exports.odbcCall = odbcCall;