migrating to typescript

src/ConsistencyEnforcer.ts

@@ -47,12 +47,7 @@ async function getIsStarted(conversion: Conversion, dataPoolId: number): Promise
 
     const dbAccess: DBAccess = new DBAccess(conversion);
     const result: DBAccessQueryResult = await dbAccess.query(logTitle, sql, DBVendors.PG, false, false);
-
-    if ('rows' in result.data) {
-        return Array.isArray(result.data.rows) ? !!result.data.rows[0].is_started : false;
-    }
-
-    return false;
+    return result.error ? false : !!result.data.rows[0].is_started;
 }
 
 /**
@@ -68,12 +63,7 @@ async function hasCurrentChunkLoaded(conversion: Conversion, chunk: any): Promis
 
     const dbAccess: DBAccess = new DBAccess(conversion);
     const result: DBAccessQueryResult = await dbAccess.query(logTitle, sql, DBVendors.PG, false, false);
-
-    if ('rows' in result.data) {
-        return Array.isArray(result.data.rows) ? !!result.data.rows[0].exists : true;
-    }
-
-    return true;
+    return result.error ? true : !!result.data.rows[0].exists;
 }
 
 /**

src/DBAccess.ts

@@ -178,10 +178,10 @@ export default class DBAccess {
                 if (error) {
                     // An error occurred during DB querying.
                     generateError(this._conversion, `\t--[${ caller }] ${ error }`, sql);
-                    return processExitOnError ? process.exit() : reject({ client: client, data: error });
+                    return processExitOnError ? process.exit() : reject({ client: client, data: undefined, error: error });
                 }
 
-                return resolve({ client: client, data: data });
+                return resolve({ client: client, data: data, error: undefined });
             });
         });
     }
@@ -207,11 +207,11 @@ export default class DBAccess {
                 client = undefined;
             }
 
-            return { client: client, data: data };
+            return { client: client, data: data, error: undefined };
         } catch (error) {
             // An error occurred during DB querying.
             generateError(this._conversion, `\t--[${ caller }] ${ error }`, sql);
-            return processExitOnError ? process.exit() : { client: client, data: error };
+            return processExitOnError ? process.exit() : { client: client, data: undefined, error: error };
         }
     }
 }

src/DBAccessQueryResult.ts

@@ -30,6 +30,13 @@ export default interface DBAccessQueryResult {
 
     /**
      * Query result.
+     * The data may be undefined.
      */
-    data: any;
+    data?: any;
+
+    /**
+     * Query error.
+     * The data may be undefined.
+     */
+    error?: any;
 }

src/ViewGenerator.ts

@@ -18,40 +18,30 @@
  *
  * @author Anatoly Khaytovich <anatolyuss@gmail.com>
  */
-'use strict';
-
-const fs                    = require('fs');
-const path                  = require('path');
-const log                   = require('./Logger');
-const generateError         = require('./ErrorGenerator');
-const migrationStateManager = require('./MigrationStateManager');
+import * as fs from 'fs';
+import * as path from 'path';
+import log from './Logger';
+import Conversion from './Conversion';
+import DBAccess from './DBAccess';
+import DBVendors from './DBVendors';
+import * as extraConfigProcessor from './ExtraConfigProcessor';
 
 /**
  * Attempts to convert MySQL view to PostgreSQL view.
- *
- * @param {String} schema
- * @param {String} viewName
- * @param {String} mysqlViewCode
- *
- * @returns {String}
  */
-const generateView = (schema, viewName, mysqlViewCode) => {
-    mysqlViewCode          = mysqlViewCode.split('`').join('"');
-    const queryStart       = mysqlViewCode.indexOf('AS');
-    mysqlViewCode          = mysqlViewCode.slice(queryStart);
-    const arrMysqlViewCode = mysqlViewCode.split(' ');
+function generateView(schema: string, viewName: string, mysqlViewCode: string): string {
+    mysqlViewCode = mysqlViewCode.split('`').join('"');
+    const queryStart: number = mysqlViewCode.indexOf('AS');
+    mysqlViewCode = mysqlViewCode.slice(queryStart);
+    const arrMysqlViewCode: string[] = mysqlViewCode.split(' ');
 
-    for (let i = 0; i < arrMysqlViewCode.length; ++i) {
-        if (
-            arrMysqlViewCode[i].toLowerCase() === 'from'
-            || arrMysqlViewCode[i].toLowerCase() === 'join'
-            && i + 1 < arrMysqlViewCode.length
-        ) {
-            arrMysqlViewCode[i + 1] = '"' + schema + '".' + arrMysqlViewCode[i + 1];
+    arrMysqlViewCode.forEach((str: string, index: number) => {
+        if (str.toLowerCase() === 'from' || str.toLowerCase() === 'join' && index + 1 < arrMysqlViewCode.length) {
+            arrMysqlViewCode[index + 1] = `"${ schema }".${ arrMysqlViewCode[index + 1] }`;
         }
-    }
+    });
 
-    return 'CREATE OR REPLACE VIEW "' + schema + '"."' + viewName + '" ' + arrMysqlViewCode.join(' ') + ';';
+    return `CREATE OR REPLACE VIEW "${ schema }"."${ viewName }" ${ arrMysqlViewCode.join(' ') };`;
 }
 
 /**
@@ -61,9 +51,9 @@ const generateView = (schema, viewName, mysqlViewCode) => {
  * @param {String}     viewName
  * @param {String}     sql
  *
- * @returns {undefined}
+ * @returns {undefined} TODO: refactor to return Promise<void>!!!
  */
-const logNotCreatedView = (self, viewName, sql) => {
+const logNotCreatedView = (conversion: Conversion, viewName: string, sql: string) => {
     fs.stat(self._notCreatedViewsPath, (directoryDoesNotExist, stat) => {
         if (directoryDoesNotExist) {
             fs.mkdir(self._notCreatedViewsPath, self._0777, e => {
@@ -169,4 +159,4 @@ module.exports = self => {
             Promise.all(createViewPromises).then(() => resolve());
         });
     });
-};
+}