feat: adds lesson_23 homework and lesson_24 pre-work (#729)

Signed-off-by: Anthony D. Mays <anthony@morganlatimer.com>

Author: anthonydmays

lesson_23/README.md

@@ -19,4 +19,49 @@ Please review the following resources before lecture:
 
 ## Homework
 
-- TODO(anthonydmays): Define requirements and stuff...
+- [ ] Complete the [Creating a Library API](#creating-a-library-api) assignment.
+- [ ] Do pre-work for [lesson 27](/lesson_27/).
+
+### Creating a Library API
+
+We are continuing to build atop the foundation of our library app. For this assignment, you will help implement the API that will be used by a yet-to-come front-end app.
+
+* You will implement the [MediaItemsController][controller-file] to enable the following API:
+   * `GET /items` - Retrieves a list of media items
+   * `POST /items` - Creates a new media item
+   * `GET /items/:id` - Retrieves a single media item with the given ID.
+   * `DELETE /items/:id` - Deletes a single media item with the given ID.
+* Study the tests in [MediaItemsControllerTest][controller-test-file] to understand what you should accept and return in the API.
+* You should not need to make any code changes outside of the `com.codedifferently.lesson23.web` package.
+
+#### Running the API
+
+You can run the server using the usual `./gradlew run --console=plain` command from the `api/java` directory. If you want to test that the server is running correctly, you can use `curl` like so:
+
+```bash
+curl http://localhost:3001/items | json_pp
+```
+
+The project also includes an OpenAPI user interface (Swagger) for navigating the API. Just visit http://localhost:3001/swagger-ui.html to access it.
+
+Alternatively, you can also test the API using the tool [Postman][postman-link]. I recommend installing this tool to make it easier to test things.
+
+#### Debugging the API
+
+Remember that you can debug the API by visiting the main function in [Lesson23.java][main-file] and clicking `Debug main`. You'll be able to set breakpoints in your code to see what's happening and fix issues.
+
+![Debugging the API](./debug.png)
+
+
+#### TypeScript API
+
+This project also includes a fully functioning TypeScript version of the Java project. You can visit `api/javascript/api_app` to execute it using `npm start` and view the OpenAPI documentation at http://localhost:3000/api (note that it runs on port 3000).
+
+## Additional resources
+
+* [gRPC vs REST: Comparing API Styles in Practice (Article)](https://dev.to/anthonydmays/grpc-vs-rest-comparing-api-styles-in-practice-4bl): This article explains why the stuff most people call REST isn't actually.
+
+[controller-file]: ./api/java/api_app/src/main/java/com/codedifferently/lesson23/web/MediaItemsController.java
+[controller-test-file]: ./api/java/api_app/src/test/java/com/codedifferently/lesson23/web/MediaItemsControllerTest.java
+[postman-link]: https://www.postman.com/downloads/
+[main-file]: ./api/java/api_app/src/main/java/com/codedifferently/lesson23/Lesson23.java

lesson_23/api/java/.gitattributes

@@ -0,0 +1,9 @@
+#
+# https://help.github.com/articles/dealing-with-line-endings/
+#
+# Linux start script should use lf
+/gradlew        text eol=lf
+
+# These are Windows script files and should use crlf
+*.bat           text eol=crlf
+

lesson_23/api/java/.gitignore

@@ -0,0 +1,5 @@
+# Ignore Gradle project-specific cache directory
+.gradle
+
+# Ignore Gradle build output directory
+build

lesson_23/api/java/api_app/build.gradle.kts

@@ -0,0 +1,82 @@
+plugins {
+    // Apply the application plugin to add support for building a CLI application in Java.
+    application
+    eclipse
+    id("com.diffplug.spotless") version "6.25.0"
+	  id("org.springframework.boot") version "3.4.0"
+    id("com.adarshr.test-logger") version "4.0.0"
+}
+
+apply(plugin = "io.spring.dependency-management")
+
+repositories {
+    // Use Maven Central for resolving dependencies.
+    mavenCentral()
+}
+
+dependencies {
+    // Use JUnit Jupiter for testing.
+    testImplementation("com.codedifferently.instructional:instructional-lib")
+    testImplementation("org.junit.jupiter:junit-jupiter:5.11.3")
+    testImplementation("org.springframework.boot:spring-boot-starter-test")
+    testImplementation("org.assertj:assertj-core:3.26.3")
+    testImplementation("at.favre.lib:bcrypt:0.10.2")
+    testImplementation("org.springframework.boot:spring-boot-starter-test")
+
+    // This dependency is used by the application.
+    implementation("com.codedifferently.instructional:instructional-lib")
+    implementation("com.google.guava:guava:33.3.1-jre")
+    implementation("com.google.code.gson:gson:2.11.0")
+    implementation("commons-cli:commons-cli:1.6.0")
+    implementation("org.springdoc:springdoc-openapi-starter-webmvc-ui:2.6.0")
+    implementation("org.springframework.boot:spring-boot-starter")
+    implementation("org.springframework.boot:spring-boot-starter-data-jpa")
+    implementation("org.springframework.boot:spring-boot-starter-validation")
+    implementation("org.springframework.boot:spring-boot-starter-web")
+    compileOnly("org.springframework.boot:spring-boot-devtools")
+    implementation("com.opencsv:opencsv:5.9")
+    implementation("org.apache.commons:commons-csv:1.10.0")
+    implementation("org.xerial:sqlite-jdbc:3.36.0")
+    implementation("org.hibernate.orm:hibernate-community-dialects:6.2.7.Final") 
+    compileOnly("org.projectlombok:lombok:1.18.38")
+    annotationProcessor("org.projectlombok:lombok:1.18.38")
+    testCompileOnly("org.projectlombok:lombok:1.18.38")
+    testAnnotationProcessor("org.projectlombok:lombok:1.18.38")
+}
+
+application {
+    // Define the main class for the application.
+    mainClass.set("com.codedifferently.lesson23.Lesson23")
+}
+
+tasks.named<JavaExec>("run") {
+    standardInput = System.`in`
+}
+
+tasks.named<Test>("test") {
+    // Use JUnit Platform for unit tests.
+    useJUnitPlatform()
+}
+
+
+configure<com.diffplug.gradle.spotless.SpotlessExtension> {
+
+  format("misc", {
+    // define the files to apply `misc` to
+    target("*.gradle", ".gitattributes", ".gitignore")
+
+    // define the steps to apply to those files
+    trimTrailingWhitespace()
+    indentWithTabs() // or spaces. Takes an integer argument if you don't like 4
+    endWithNewline()
+  })
+
+  java {
+    // don't need to set target, it is inferred from java
+
+    // apply a specific flavor of google-java-format
+    googleJavaFormat()
+    // fix formatting of type annotations
+    formatAnnotations()
+  }
+}

lesson_23/api/java/api_app/lombok.config

@@ -0,0 +1,2 @@
+# This file is generated by the 'io.freefair.lombok' Gradle plugin
+config.stopBubbling = true

lesson_23/api/java/api_app/src/main/java/com/codedifferently/lesson23/Lesson23.java

@@ -0,0 +1,39 @@
+package com.codedifferently.lesson23;
+
+import com.codedifferently.lesson23.cli.LibraryApp;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@SpringBootApplication(scanBasePackages = "com.codedifferently")
+public class Lesson23 implements CommandLineRunner {
+
+  @Autowired private LibraryApp libraryApp;
+
+  public static void main(String[] args) {
+    var application = new SpringApplication(Lesson23.class);
+    application.run(args);
+  }
+
+  @Override
+  public void run(String... args) throws Exception {
+    // Don't run as an app if we're running as a JUnit test.
+    if (isJUnitTest()) {
+      return;
+    }
+
+    libraryApp.run(args);
+  }
+
+  private static boolean isJUnitTest() {
+    for (StackTraceElement element : Thread.currentThread().getStackTrace()) {
+      if (element.getClassName().startsWith("org.junit.")) {
+        return true;
+      }
+    }
+    return false;
+  }
+}

lesson_23/api/java/api_app/src/main/java/com/codedifferently/lesson23/cli/LibraryApp.java

@@ -0,0 +1,191 @@
+package com.codedifferently.lesson23.cli;
+
+import com.codedifferently.lesson23.factory.LibraryDataLoader;
+import com.codedifferently.lesson23.library.Book;
+import com.codedifferently.lesson23.library.Library;
+import com.codedifferently.lesson23.library.LibraryInfo;
+import com.codedifferently.lesson23.library.MediaItem;
+import com.codedifferently.lesson23.library.search.SearchCriteria;
+import java.util.Map;
+import java.util.Scanner;
+import java.util.Set;
+import java.util.UUID;
+import org.apache.commons.cli.CommandLine;
+import org.apache.commons.cli.CommandLineParser;
+import org.apache.commons.cli.DefaultParser;
+import org.apache.commons.cli.HelpFormatter;
+import org.apache.commons.cli.Option;
+import org.apache.commons.cli.Options;
+import org.apache.commons.cli.ParseException;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+@Service
+public final class LibraryApp {
+
+  @Autowired private Library library;
+
+  public void run(String[] args) throws Exception {
+    // Show stats about the loaded library to the user.
+    printLibraryInfo(library);
+
+    try (var scanner = new Scanner(System.in)) {
+      LibraryCommand command;
+      // Main application loop.
+      while ((command = promptForCommand(scanner)) != LibraryCommand.EXIT) {
+        switch (command) {
+          case SEARCH -> doSearch(scanner, library);
+          default -> System.out.println("\nNot ready yet, coming soon!");
+        }
+      }
+    }
+  }
+
+  private void printLibraryInfo(Library library) {
+    LibraryInfo info = library.getInfo();
+    Map<UUID, Set<MediaItem>> checkedOutItemsByGuest = info.getCheckedOutItemsByGuest();
+    int numCheckedOutItems = checkedOutItemsByGuest.values().stream().mapToInt(Set::size).sum();
+    System.out.println();
+    System.out.println("========================================");
+    System.out.println("Library id: " + library.getId());
+    System.out.println("Number of items: " + info.getItems().size());
+    System.out.println("Number of guests: " + info.getGuests().size());
+    System.out.println("Number of checked out items: " + numCheckedOutItems);
+    System.out.println("========================================");
+    System.out.println();
+  }
+
+  private static LibraryDataLoader getLoaderOrDefault(
+      String[] args, LibraryDataLoader defaultLoader) throws Exception {
+    String loaderType = getLoaderFromCommandLine(args);
+    return loaderType == null
+        ? defaultLoader
+        : Class.forName(loaderType)
+            .asSubclass(LibraryDataLoader.class)
+            .getDeclaredConstructor()
+            .newInstance();
+  }
+
+  private static String getLoaderFromCommandLine(String[] args) throws IllegalArgumentException {
+    Options options = new Options();
+    Option input = new Option("l", "loader", true, "data loader type");
+    input.setRequired(false);
+    options.addOption(input);
+    CommandLineParser parser = new DefaultParser();
+    HelpFormatter formatter = new HelpFormatter();
+    try {
+      CommandLine cmd = parser.parse(options, args);
+      return cmd.getOptionValue("loader");
+    } catch (ParseException e) {
+      System.out.println();
+      System.out.println(e.getMessage());
+      formatter.printHelp("utility-name", options);
+
+      System.exit(1);
+    }
+    return null;
+  }
+
+  private static LibraryCommand promptForCommand(Scanner scanner) {
+    var command = LibraryCommand.UNKNOWN;
+    while (command == LibraryCommand.UNKNOWN) {
+      printMenu();
+      var input = scanner.nextLine();
+      try {
+        command = LibraryCommand.fromValue(Integer.parseInt(input.trim()));
+      } catch (IllegalArgumentException e) {
+        System.out.println("Invalid command: " + input);
+      }
+    }
+    return command;
+  }
+
+  private static void printMenu() {
+    System.out.println("\nEnter the number of the desired command:");
+    System.out.println("1) << EXIT");
+    System.out.println("2) SEARCH");
+    System.out.println("3) CHECKOUT");
+    System.out.println("4) RETURN");
+    System.out.print("command> ");
+  }
+
+  private void doSearch(Scanner scanner, Library library) {
+    LibrarySearchCommand command = promptForSearchCommand(scanner);
+    if (command == LibrarySearchCommand.RETURN) {
+      return;
+    }
+    SearchCriteria criteria = getSearchCriteria(scanner, command);
+    Set<MediaItem> results = library.search(criteria);
+    printSearchResults(results);
+  }
+
+  private LibrarySearchCommand promptForSearchCommand(Scanner scanner) {
+    var command = LibrarySearchCommand.UNKNOWN;
+    while (command == LibrarySearchCommand.UNKNOWN) {
+      printSearchMenu();
+      var input = scanner.nextLine();
+      try {
+        command = LibrarySearchCommand.fromValue(Integer.parseInt(input.trim()));
+      } catch (IllegalArgumentException e) {
+        System.out.println("Invalid command: " + input);
+      }
+    }
+    return command;
+  }
+
+  private void printSearchMenu() {
+    System.out.println("\nEnter the number of the desired search criteria:");
+    System.out.println("1) << RETURN");
+    System.out.println("2) TITLE");
+    System.out.println("3) AUTHOR");
+    System.out.println("4) TYPE");
+    System.out.print("search> ");
+  }
+
+  private SearchCriteria getSearchCriteria(Scanner scanner, LibrarySearchCommand command) {
+    System.out.println();
+    switch (command) {
+      case TITLE -> {
+        System.out.println("Enter the title to search for: ");
+        System.out.print("title> ");
+        var title = scanner.nextLine();
+        return SearchCriteria.builder().title(title).build();
+      }
+      case AUTHOR -> {
+        System.out.println("Enter the author to search for: ");
+        System.out.print("author> ");
+        var author = scanner.nextLine();
+        return SearchCriteria.builder().author(author).build();
+      }
+      case TYPE -> {
+        System.out.println("Enter the type to search for: ");
+        System.out.print("type> ");
+        var type = scanner.nextLine();
+        return SearchCriteria.builder().type(type).build();
+      }
+      default -> System.out.println("Invalid search command: " + command);
+    }
+    return null;
+  }
+
+  private void printSearchResults(Set<MediaItem> results) {
+    System.out.println();
+
+    if (results.isEmpty()) {
+      System.out.println("No results found.");
+      return;
+    }
+
+    System.out.println("Search results:\n");
+    for (MediaItem item : results) {
+      System.out.println("ID: " + item.getId());
+      System.out.println("TITLE: " + item.getTitle());
+      if (item instanceof Book book) {
+        System.out.println("AUTHOR(S): " + String.join(", ", book.getAuthors()));
+      }
+      System.out.println("TYPE: " + item.getType().toString().toUpperCase());
+      System.out.println();
+    }
+    System.out.println("Found " + results.size() + " result(s).\n");
+  }
+}