update tests for generating expected results

Author: PramodKumarYadav

src/main/java/com/powertester/database/DBConnection.java

@@ -5,6 +5,8 @@
 
 import static org.junit.jupiter.api.Assertions.fail;
 
+import java.io.BufferedReader;
+import java.io.FileReader;
 import java.sql.CallableStatement;
 import java.sql.Connection;
 import java.sql.PreparedStatement;
@@ -18,7 +20,6 @@
 import java.util.Map;
 import lombok.extern.slf4j.Slf4j;
 import com.powertester.config.TestConfig;
-import com.powertester.utils.SqlUtils;
 
 @Slf4j
 public class DBConnection {
@@ -81,13 +82,6 @@ public Connection getConnection() throws SQLException {
     return connection;
   }
 
-  // Execute multiple update queries
-  public void update(List<String> sqlStatements) {
-    for (String sql : sqlStatements) {
-      update(sql);
-    }
-  }
-  
   // Execute update query
   public void update(String sql) {
     try (Connection connection = getConnection();
@@ -98,7 +92,39 @@ public void update(String sql) {
     }
   }
 
-  
+  public void updateFromFile(String filePath) {
+    List<String> statements = extractSqlStatements(filePath);
+    update(statements);
+  }
+
+  private static List<String> extractSqlStatements(String sqlFilePath) {
+      List<String> statements = new ArrayList<>();
+      try (BufferedReader reader = new BufferedReader(new FileReader(sqlFilePath))) {
+          StringBuilder queryBuilder = new StringBuilder();
+          String line;
+          while ((line = reader.readLine()) != null) {
+              line = line.trim();
+              if (line.isEmpty() || line.startsWith("--")) continue;
+              queryBuilder.append(line);
+              if (line.endsWith(";")) {
+                  statements.add(queryBuilder.toString().replace(";", ""));
+                  queryBuilder.setLength(0);
+              } else {
+                  queryBuilder.append(" ");
+              }
+          }
+      } catch (Exception e) {
+          throw new SqlFileReadException("Failed to read SQL file: " + sqlFilePath, e);
+      }
+      return statements;
+  }
+
+  // Execute multiple update queries
+  private void update(List<String> sqlStatements) {
+    for (String sql : sqlStatements) {
+      update(sql);
+    }
+  }
 
   // Preferred option 1: Execute a prepared statement and return the resultSet data as a list of map
   // of column name and value
@@ -122,7 +148,7 @@ public List<Map<String, String>> query(String sql, String... parameters) {
 
   // Create another method for executePreparedStatement which accepts file paths that contains SQLs to execute
   public List<Map<String, String>> queryFromFile(String filePath) {
-    String sql = SqlUtils.readSqlFromFile(filePath);
+    String sql = extractSqlStatements(filePath).get(0);
     return query(sql);
   }
 
@@ -183,3 +209,12 @@ public void closeConnectionPool() {
     dataSource.close();
   }
 }
+
+/**
+ * Custom exception for SQL file reading errors.
+ */
+class SqlFileReadException extends RuntimeException {
+    public SqlFileReadException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/com/powertester/utils/CsvUtils.java

@@ -17,7 +17,7 @@ public class CsvUtils {
     private CsvUtils() {}
 
     // Read CSV into List<Map<String, String>>
-    public static List<Map<String, String>> readCsvToMapList(String filePath) throws IOException {
+    public static List<Map<String, String>> convertCsvToListOfMap(String filePath) throws IOException {
         List<Map<String, String>> rows = new ArrayList<>();
 
         CSVFormat csvFormat = CSVFormat.Builder.create()
@@ -39,7 +39,7 @@ public static List<Map<String, String>> readCsvToMapList(String filePath) throws
     }
 
     // Write List<Map<String, String>> to CSV
-    public static void writeMapListToCsv(String filePath, List<Map<String, String>> data) throws IOException {
+    public static void saveDataToCsvFile(String filePath, List<Map<String, String>> data) throws IOException {
         if (data.isEmpty()) return;
 
         CSVFormat csvFormat = CSVFormat.Builder.create()

src/main/java/com/powertester/utils/SqlUtils.java

@@ -13,7 +13,6 @@
 
 import com.powertester.extensions.TableCompareExtension;
 import com.powertester.utils.CsvUtils;
-import com.powertester.utils.SqlUtils;
 
 @Slf4j
 class DBConnectionPassingTest {
@@ -23,12 +22,11 @@ class DBConnectionPassingTest {
     static void createTables() {
         // Read and execute each SQL statement from input.sql
         String sqlFilePath = "src/test/resources/data/tc03-inactive-customers/input.sql";
-        List<String> statements = SqlUtils.readSqlStatements(sqlFilePath);
-        db.update(statements);
+        db.updateFromFile(sqlFilePath);
     }
 
     @Test
-    void testCompareEmpAndCustomerTables() {
+    void compareOutputOfTwoSQLStatements() {
         // Arrange: input (could be done at a test, class or at project level)
 
         // Act: (run the application to process input data). If the app is real time like APIs, this can be done at the test level. 
@@ -46,15 +44,15 @@ void testCompareEmpAndCustomerTables() {
     }
 
     @Test
-    void testUsingExpectedCustomerCSVAndActualSQLOutput() throws java.io.IOException {
+    void compareOutputOfSQLStatementWithAExpectedCSVFile() throws java.io.IOException {
         // Arrange: input (could be done at a test, class or at project level)
 
         // Act: (run the application to process input data). If the app is real time like APIs, this can be done at the test level. 
         // But if the app works as a batch and takes significant time to process data, it might also make sense to do this at the project level.
 
         // Assert: Get input and output data to compare
         String expectedCSVFilePath = "src/test/resources/data/tc03-inactive-customers/expected.csv";
-        List<Map<String, String>> expectedCustomers = CsvUtils.readCsvToMapList(expectedCSVFilePath);
+        List<Map<String, String>> expectedCustomers = CsvUtils.convertCsvToListOfMap(expectedCSVFilePath);
 
         String outputSQLFilePath = "src/test/resources/data/tc03-inactive-customers/output.sql";
         List<Map<String, String>> actualCustomers = db.queryFromFile(outputSQLFilePath);

src/test/java/com/powertester/database/DBConnectionPassingTest.java

@@ -21,51 +21,23 @@ class CreateExpectedCSVFileTest {
 
     @BeforeAll
     static void createTables() {
-        // Create tables with more fields
-        db.update(
-                "CREATE TABLE student (id INT PRIMARY KEY, first_name VARCHAR(255), last_name VARCHAR(255), age INT, gender VARCHAR(10))");
-
-        // Clean tables before each test to avoid PK violation in repeated tests
-        db.update("DELETE FROM student");
-
-        // Insert 3 records directly
-        db.update(
-                "INSERT INTO student (id, first_name, last_name, age, gender) VALUES (1, 'John', 'Doe', 30, 'Male')");
-        db.update(
-                "INSERT INTO student (id, first_name, last_name, age, gender) VALUES (2, 'Jane', 'Smith', 25, 'Female')");
-        db.update(
-                "INSERT INTO student (id, first_name, last_name, age, gender) VALUES (3, 'Alex', 'Brown', 28, 'Male')");
+        // Read and execute each SQL statement from input.sql
+        String sqlFilePath = "src/test/resources/data/create-expected-csv-file-test/input.sql";
+        db.updateFromFile(sqlFilePath);
     }
 
     @Test
     void generateExpectedCSVFileFromActualSQLOutput() throws java.io.IOException {
         // Arrange: Create expected results CSV based on actual SQL output. Later adjust the values as per requirements.
-        List<Map<String, String>> actualRows = db.query("SELECT * FROM student");
-
-        // Generate expected csv file.
-        String expectedCSVFilePath = "src/test/resources/data/tc02-premium-customers/expected.csv";
-        CsvUtils.writeMapListToCsv(expectedCSVFilePath, actualRows);
-
-        // Get the generated CSV file
-        List<Map<String, String>> expectedRows = CsvUtils.readCsvToMapList(expectedCSVFilePath);
-        TableCompareExtension.captureRows(expectedRows, actualRows);
-
-        // Completeness check: Assert that both input and output are of same size.
-        assertEquals(expectedRows.size(), actualRows.size());
-    }
-
-    @Test
-    void generateExpectedCSVFileFromActualSQLOutputFile() throws java.io.IOException {
-        // Arrange: Create expected results CSV based on actual SQL output. Later adjust the values as per requirements.
-        String outputSQLFilePath = "src/test/resources/data/tc01-new-customers/output.sql";
+        String outputSQLFilePath = "src/test/resources/data/create-expected-csv-file-test/output.sql";
         List<Map<String, String>> actualRows = db.queryFromFile(outputSQLFilePath);
 
         // Generate expected csv file.
-        String expectedCSVFilePath = "src/test/resources/data/tc01-new-customers/expected.csv";
-        CsvUtils.writeMapListToCsv(expectedCSVFilePath, actualRows);
+        String expectedCSVFilePath = "src/test/resources/data/create-expected-csv-file-test/expected.csv";
+        CsvUtils.saveDataToCsvFile(expectedCSVFilePath, actualRows);
 
         // Get the generated CSV file
-        List<Map<String, String>> expectedRows = CsvUtils.readCsvToMapList(expectedCSVFilePath);
+        List<Map<String, String>> expectedRows = CsvUtils.convertCsvToListOfMap(expectedCSVFilePath);
         TableCompareExtension.captureRows(expectedRows, actualRows);
 
         // Completeness check: Assert that both input and output are of same size.

src/test/java/com/powertester/utils/CreateExpectedCSVFileTest.java

@@ -0,0 +1,4 @@
+ID,FIRST_NAME,LAST_NAME,AGE,GENDER
+1,John,Doe,30,Male
+2,Jane,Smith,25,Female
+3,Alex,Brown,28,Male

src/test/resources/data/create-expected-csv-file-test/expected.csv

@@ -0,0 +1,10 @@
+-- Create tables with more fields
+CREATE TABLE student (id INT PRIMARY KEY, first_name VARCHAR(255), last_name VARCHAR(255), age INT, gender VARCHAR(10));
+
+-- Clean tables before each test to avoid PK violation in repeated tests
+DELETE FROM student;
+
+-- Insert 3 records directly
+INSERT INTO student (id, first_name, last_name, age, gender) VALUES (1, 'John', 'Doe', 30, 'Male');
+INSERT INTO student (id, first_name, last_name, age, gender) VALUES (2, 'Jane', 'Smith', 25, 'Female');
+INSERT INTO student (id, first_name, last_name, age, gender) VALUES (3, 'Alex', 'Brown', 28, 'Male');

src/test/resources/data/create-expected-csv-file-test/input.sql

@@ -0,0 +1 @@
+SELECT * FROM student;

src/test/resources/data/create-expected-csv-file-test/output.sql

@@ -1 +1 @@
-SELECT * FROM student
+SELECT * FROM student;

src/test/resources/data/tc01-new-customers/output.sql

@@ -1 +1 @@
-SELECT * FROM customer
+SELECT * FROM customer;