Add Flyway repair strategy for duplicate V14 migration checksum mismatch

FLYWAY_REPAIR_INSTRUCTIONS.md

@@ -0,0 +1,110 @@
+# Flyway Migration Repair Instructions
+
+## What This Fix Does
+
+This fix adds a temporary Flyway migration strategy to the `FitnessAppApplication` class that:
+
+1. **Repairs** the `flyway_schema_history` table to fix checksum mismatches
+2. **Migrates** the database schema to apply any pending migrations
+
+This is necessary because there are duplicate V14 migration files with different checksums:
+- `V14__create_usda_food_tables.sql`
+- `V14__seed_default_api_key.sql`
+
+## How to Use This Fix
+
+### Step 1: Start the Application
+
+Run the backend application using Gradle:
+
+```bash
+cd backend
+./gradlew bootRun
+```
+
+Or if you prefer the start script:
+
+```bash
+cd backend
+./start.sh
+```
+
+### Step 2: Verify Successful Startup
+
+Watch the console logs for:
+- `Successfully repaired schema history table` (from Flyway repair)
+- `Successfully applied X migrations` or `Schema is up to date` (from Flyway migrate)
+- `Started FitnessAppApplication` (indicating successful startup)
+
+### Step 3: **IMPORTANT** - Remove the Repair Bean
+
+Once the application starts successfully, **immediately** remove the temporary repair code:
+
+1. Open `backend/src/main/java/com/fitnessapp/backend/FitnessAppApplication.java`
+
+2. Delete the `repairStrategy()` method and its documentation:
+   ```java
+   // DELETE THESE LINES:
+   /**
+    * Temporary Flyway migration strategy to repair checksum mismatches.
+    * This bean performs a Flyway repair operation before running migrations,
+    * which fixes any checksum inconsistencies in the flyway_schema_history table.
+    * 
+    * IMPORTANT: This bean should be removed after the application starts successfully
+    * and the database schema history is repaired. It's only needed for one-time repair.
+    */
+   @Bean
+   public FlywayMigrationStrategy repairStrategy() {
+       return flyway -> {
+           // Repair the schema history table to fix checksum mismatches
+           flyway.repair();
+           // Then proceed with normal migration
+           flyway.migrate();
+       };
+   }
+   ```
+
+3. Also remove the import that's no longer needed:
+   ```java
+   // DELETE THIS LINE:
+   import org.springframework.boot.autoconfigure.flyway.FlywayMigrationStrategy;
+
+   // DELETE THIS LINE:
+   import org.springframework.context.annotation.Bean;
+   ```
+
+4. Save the file
+
+5. Restart the application to verify it still works without the repair strategy
+
+## Why Remove the Bean?
+
+The repair strategy should only run **once** to fix the checksum mismatch. Keeping it in the code means:
+- It will run on every application startup (unnecessary overhead)
+- It could mask future migration problems
+- It's not needed once the database schema history is corrected
+
+## What If It Doesn't Work?
+
+If the application fails to start with this fix:
+
+1. Check the error logs for specific Flyway errors
+2. Verify your database connection settings in `application.yml`
+3. Ensure PostgreSQL is running and accessible
+4. Check that you have the correct database credentials
+
+## Root Cause
+
+The issue occurred because two migration files were created with the same version number (V14):
+- One for creating USDA food tables
+- One for seeding default API keys
+
+Flyway expects each migration version to be unique and immutable. When the content of a migration changes, its checksum changes, causing validation failures.
+
+## Long-term Solution
+
+To prevent this in the future:
+1. Always use unique version numbers for migrations
+2. Never modify existing migration files after they've been applied
+3. Use incremental version numbers (V16, V17, V18, etc.)
+4. Consider renaming one of the V14 files to V16 or higher in a future clean migration

backend/src/main/java/com/fitnessapp/backend/FitnessAppApplication.java

@@ -2,8 +2,10 @@
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.autoconfigure.flyway.FlywayMigrationStrategy;
 import org.springframework.boot.context.properties.ConfigurationPropertiesScan;
 import org.springframework.cache.annotation.EnableCaching;
+import org.springframework.context.annotation.Bean;
 import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
 
 @SpringBootApplication
@@ -22,6 +24,24 @@ public class FitnessAppApplication {
     public static void main(String[] args) {
         SpringApplication.run(FitnessAppApplication.class, args);
     }
+
+    /**
+     * Temporary Flyway migration strategy to repair checksum mismatches.
+     * This bean performs a Flyway repair operation before running migrations,
+     * which fixes any checksum inconsistencies in the flyway_schema_history table.
+     * 
+     * IMPORTANT: This bean should be removed after the application starts successfully
+     * and the database schema history is repaired. It's only needed for one-time repair.
+     */
+    @Bean
+    public FlywayMigrationStrategy repairStrategy() {
+        return flyway -> {
+            // Repair the schema history table to fix checksum mismatches
+            flyway.repair();
+            // Then proceed with normal migration
+            flyway.migrate();
+        };
+    }
 }