feat: Dean Lesson 09 implement bulk sample file generation

lesson_09/types/types_app/DWREADME.md

@@ -0,0 +1,70 @@
+Bulk Sample Generator
+
+In addition to completing the above assignment, you are tasked with adding a flag to the app that will allow it to bulk generate sample files dynamically for each DataProvider implementation.
+
+## How to Run the Bulk Generator
+
+The app now supports a bulk generation mode that will automatically discover all DataProvider implementations and generate sample JSON files for each one.
+
+### Command Usage
+
+To run the bulk generator, use either of these command-line flags:
+
+```bash
+# Using the long flag
+./gradlew bootRun --args="--bulk"
+
+# Using the short flag
+./gradlew bootRun --args="-b"
+```
+
+### What It Does
+
+When you run the app with the `--bulk` or `-b` flag, it will:
+
+1. **Discover all DataProvider implementations** - The app automatically finds all classes that extend `DataProvider` and are annotated with `@Service`
+2. **Loop through each provider** - For each discovered provider (e.g., `AnthonyMaysProvider`, `DeanWalstonProvider`, etc.)
+3. **Generate sample data** - Creates 10 rows of sample data based on each provider's column type specifications
+4. **Save to JSON files** - Saves each provider's sample data to `{providerName}.json` in the `src/main/resources/data/` directory
+
+### Example Output
+
+If the app finds providers like `AnthonyMaysProvider` and `DeanWalstonProvider`, it will generate:
+- `anthonymays.json` - Sample data based on AnthonyMaysProvider's column specifications
+- `deanwalston.json` - Sample data based on DeanWalstonProvider's column specifications
+
+### Sample Console Output
+
+```
+Bulk generating sample files for all DataProvider implementations...
+Found 2 DataProvider implementations:
+- Generating sample file for: anthonymays
+  Column specifications for anthonymays:
+    - column1: Integer
+    - column2: String
+    - column3: Boolean
+    - column4: Float
+    - column5: Double
+    - column6: Long
+    - column7: Short
+  ✓ Generated: anthonymays.json
+- Generating sample file for: deanwalston
+  Column specifications for deanwalston:
+    - column1: Long
+    - column2: Short
+    - column3: Double
+    - column4: Integer
+    - column5: Boolean
+    - column6: String
+    - column7: Float
+  ✓ Generated: deanwalston.json
+Bulk generation completed! Files saved to: /path/to/src/main/resources/data
+```
+
+### Regular Usage (Single Provider)
+
+The app still supports generating files for individual providers:
+
+```bash
+./gradlew bootRun --args="deanwalston"
+``` 

lesson_09/types/types_app/src/main/java/com/codedifferently/lesson9/Lesson9.java

@@ -1,8 +1,12 @@
 package com.codedifferently.lesson9;
 
+import com.codedifferently.lesson9.dataprovider.DataProvider;
+import com.codedifferently.lesson9.generator.BulkSampleFileGenerator;
 import com.codedifferently.lesson9.generator.SampleFileGenerator;
 import java.io.File;
 import java.nio.file.Paths;
+import java.util.Collection;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.CommandLineRunner;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
@@ -12,22 +16,34 @@
 @SpringBootApplication(scanBasePackages = "com.codedifferently")
 public class Lesson9 implements CommandLineRunner {
 
+  @Autowired private Collection<DataProvider> dataProviders;
+
   public static void main(String[] args) {
     var application = new SpringApplication(Lesson9.class);
     application.run(args);
   }
 
+  @Override
   public void run(String... args) throws Exception {
     if (args.length == 0) {
       return;
     }
 
+    String path = getDataPath();
+
+    // Check for bulk generation flag
+    if (args[0].equals("--bulk") || args[0].equals("-b")) {
+      System.out.println("Bulk generating sample files for all DataProvider implementations...");
+      var bulkGenerator = new BulkSampleFileGenerator();
+      bulkGenerator.createBulkTestFiles(path, dataProviders);
+      return;
+    }
+
     var providerName = args[0];
     if (providerName == null) {
       throw new IllegalArgumentException("Provider name is required");
     }
 
-    String path = getDataPath();
     var fileGenerator = new SampleFileGenerator();
     fileGenerator.createTestFile(path, providerName);
   }

lesson_09/types/types_app/src/main/java/com/codedifferently/lesson9/dataprovider/DeanWalstonProvider.java

@@ -0,0 +1,23 @@
+package com.codedifferently.lesson9.dataprovider;
+
+import java.util.Map;
+import org.springframework.stereotype.Service;
+
+@Service
+public class DeanWalstonProvider extends DataProvider {
+
+  public String getProviderName() {
+    return "deanwalston";
+  }
+
+  public Map<String, Class> getColumnTypeByName() {
+    return Map.of(
+        "column1", Long.class,
+        "column2", Short.class,
+        "column3", Double.class,
+        "column4", Integer.class,
+        "column5", Boolean.class,
+        "column6", String.class,
+        "column7", Float.class);
+  }
+}

lesson_09/types/types_app/src/main/java/com/codedifferently/lesson9/generator/BulkSampleFileGenerator.java

@@ -0,0 +1,130 @@
+package com.codedifferently.lesson9.generator;
+
+import com.codedifferently.lesson9.dataprovider.DataProvider;
+import com.codedifferently.lesson9.generator.Generators.BooleanValueGenerator;
+import com.codedifferently.lesson9.generator.Generators.DoubleValueGenerator;
+import com.codedifferently.lesson9.generator.Generators.FloatValueGenerator;
+import com.codedifferently.lesson9.generator.Generators.IntValueGenerator;
+import com.codedifferently.lesson9.generator.Generators.LongValueGenerator;
+import com.codedifferently.lesson9.generator.Generators.ShortValueGenerator;
+import com.codedifferently.lesson9.generator.Generators.StringValueGenerator;
+import com.google.gson.GsonBuilder;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+/** A class to bulk generate sample files with random data for all DataProvider implementations. */
+public class BulkSampleFileGenerator {
+
+  private static final Map<Class<?>, ValueGenerator> GENERATOR_BY_TYPE =
+      Map.of(
+          Integer.class, new IntValueGenerator(),
+          String.class, new StringValueGenerator(),
+          Double.class, new DoubleValueGenerator(),
+          Short.class, new ShortValueGenerator(),
+          Long.class, new LongValueGenerator(),
+          Float.class, new FloatValueGenerator(),
+          Boolean.class, new BooleanValueGenerator());
+
+  /**
+   * Create test files with sample data for all provided DataProvider implementations.
+   *
+   * @param path the path to the directory where the files will be created
+   * @param dataProviders the collection of all DataProvider implementations
+   */
+  public void createBulkTestFiles(String path, Collection<DataProvider> dataProviders) {
+    System.out.println("Found " + dataProviders.size() + " DataProvider implementations:");
+
+    for (DataProvider provider : dataProviders) {
+      System.out.println("- Generating sample file for: " + provider.getProviderName());
+      createTestFileForProvider(path, provider);
+    }
+
+    System.out.println("Bulk generation completed! Files saved to: " + path);
+  }
+
+  /**
+   * Create a test file with sample data for a specific DataProvider.
+   *
+   * @param path the path to the directory where the file will be created
+   * @param provider the DataProvider implementation
+   */
+  private void createTestFileForProvider(String path, DataProvider provider) {
+    Map<String, Class> columnTypeByName = provider.getColumnTypeByName();
+
+    System.out.println("  Column specifications for " + provider.getProviderName() + ":");
+    columnTypeByName.forEach(
+        (column, type) -> System.out.println("    - " + column + ": " + type.getSimpleName()));
+
+    ArrayList<Map<String, String>> rows = createSampleDataForProvider(columnTypeByName);
+    saveToJsonFile(path, provider.getProviderName(), rows);
+  }
+
+  /**
+   * Create sample data rows based on the column type mapping from a DataProvider.
+   *
+   * @param columnTypeByName mapping of column names to their Java types
+   * @return list of sample data rows
+   */
+  private ArrayList<Map<String, String>> createSampleDataForProvider(
+      Map<String, Class> columnTypeByName) {
+    var rows = new ArrayList<Map<String, String>>();
+    for (var i = 0; i < 10; ++i) {
+      Map<String, String> row = createRowForProvider(columnTypeByName);
+      rows.add(row);
+    }
+    return rows;
+  }
+
+  /**
+   * Create a single row of sample data based on column type mapping.
+   *
+   * @param columnTypeByName mapping of column names to their Java types
+   * @return a single sample data row
+   */
+  private Map<String, String> createRowForProvider(Map<String, Class> columnTypeByName) {
+    var row = new LinkedHashMap<String, String>();
+    for (Map.Entry<String, Class> entry : columnTypeByName.entrySet()) {
+      String columnName = entry.getKey();
+      Class<?> columnType = entry.getValue();
+
+      ValueGenerator generator = GENERATOR_BY_TYPE.get(columnType);
+      if (generator != null) {
+        row.put(columnName, generator.generateValue());
+      } else {
+        System.err.println(
+            "Warning: No generator found for type "
+                + columnType.getName()
+                + " in column "
+                + columnName
+                + ". Using default string value.");
+        row.put(columnName, "unknown_type_" + columnType.getSimpleName());
+      }
+    }
+    return row;
+  }
+
+  /**
+   * Save the sample data to a JSON file.
+   *
+   * @param path the directory path
+   * @param providerName the name of the provider (used as filename)
+   * @param rows the sample data rows
+   */
+  private void saveToJsonFile(
+      String path, String providerName, ArrayList<Map<String, String>> rows) {
+    var file = new File(path + File.separator + providerName + ".json");
+    file.getParentFile().mkdirs();
+    var gson = new GsonBuilder().setPrettyPrinting().create();
+    try (var writer = new FileWriter(file, false)) {
+      writer.write(gson.toJson(rows));
+      System.out.println("  ✓ Generated: " + file.getName());
+    } catch (IOException e) {
+      System.err.println("  ✗ Failed to generate file for " + providerName + ": " + e.getMessage());
+    }
+  }
+}

lesson_09/types/types_app/src/main/resources/data/deanwalston.json

@@ -0,0 +1,92 @@
+[
+  {
+    "column4": "389971082",
+    "column5": "false",
+    "column6": "nshdc",
+    "column7": "6.135183E36",
+    "column1": "3383887488801300480",
+    "column2": "1566",
+    "column3": "2.815708965672392E307"
+  },
+  {
+    "column4": "375126042",
+    "column5": "true",
+    "column6": "yxpo0",
+    "column7": "3.3008857E38",
+    "column1": "4982624173995602944",
+    "column2": "27838",
+    "column3": "1.6758536573713958E308"
+  },
+  {
+    "column4": "574661113",
+    "column5": "false",
+    "column6": "atg4b7f",
+    "column7": "1.9907885E38",
+    "column1": "2889725125587536384",
+    "column2": "797",
+    "column3": "8.985254883099615E307"
+  },
+  {
+    "column4": "1983492216",
+    "column5": "false",
+    "column6": "gpchwf3skxmq",
+    "column7": "2.2199312E38",
+    "column1": "3642242784260707328",
+    "column2": "26373",
+    "column3": "4.832903782287359E307"
+  },
+  {
+    "column4": "683979250",
+    "column5": "false",
+    "column6": "3aw7tn",
+    "column7": "8.124872E37",
+    "column1": "2380753608752845312",
+    "column2": "20936",
+    "column3": "6.508463623033705E307"
+  },
+  {
+    "column4": "1029159949",
+    "column5": "false",
+    "column6": "tpul1yg",
+    "column7": "1.5425769E37",
+    "column1": "8093440394763274240",
+    "column2": "4228",
+    "column3": "3.5232401779434665E306"
+  },
+  {
+    "column4": "201841596",
+    "column5": "true",
+    "column6": "xhtopi2n9",
+    "column7": "2.654272E37",
+    "column1": "5247748052229204992",
+    "column2": "30751",
+    "column3": "8.465599922833556E307"
+  },
+  {
+    "column4": "941802560",
+    "column5": "false",
+    "column6": "ui6d7zhvl5",
+    "column7": "3.3986773E38",
+    "column1": "7733210581626198016",
+    "column2": "20785",
+    "column3": "1.6842403765767673E308"
+  },
+  {
+    "column4": "699391538",
+    "column5": "false",
+    "column6": "wtvdghcs23b",
+    "column7": "1.8785126E38",
+    "column1": "5024689015537510400",
+    "column2": "29837",
+    "column3": "1.5566962567613336E308"
+  },
+  {
+    "column4": "1585384699",
+    "column5": "false",
+    "column6": "nqbjfw9mdt0",
+    "column7": "1.855844E38",
+    "column1": "7907910887862272000",
+    "column2": "21227",
+    "column3": "1.3471632227822855E307"
+  }
+]