feat: Migrate to SLF4J for logging and update dependencies (#150)

* feat: Migrate to SLF4J for logging and update dependencies

Replaced `java.util.logging` with SLF4J. Updated Gradle configurations to include `slf4j-api` and `slf4j-simple`. Adjusted tests and container logging to reflect new logging framework.

Fixes #128

Signed-off-by: Eric Deandrea <[email protected]>

* feat: Migrate to SLF4J for logging and update dependencies

Replaced `java.util.logging` with SLF4J. Updated Gradle configurations to include `slf4j-api` and `slf4j-simple`. Adjusted tests and container logging to reflect new logging framework.

Fixes #128

Signed-off-by: Eric Deandrea <[email protected]>

---------

Signed-off-by: Eric Deandrea <[email protected]>

Author: edeandrea

docling-serve/docling-serve-client/build.gradle.kts

@@ -7,11 +7,13 @@ description = "Docling Serve Client"
 
 dependencies {
   api(project(":docling-serve-api"))
+  api(libs.slf4j.api)
   implementation(platform(libs.jackson.bom))
   implementation(libs.jackson.databind)
   implementation(libs.jackson2.databind)
 
   testImplementation(platform(libs.testcontainers.bom))
   testImplementation(libs.testcontainers.junit.jupiter)
   testImplementation(project(":docling-testcontainers"))
+  testImplementation(libs.slf4j.simple)
 }

docling-serve/docling-serve-client/src/main/java/ai/docling/serve/client/DoclingServeClient.java

@@ -14,8 +14,9 @@
 import java.util.Objects;
 import java.util.Optional;
 import java.util.concurrent.Flow.Subscriber;
-import java.util.logging.Level;
-import java.util.logging.Logger;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import ai.docling.serve.api.DoclingServeApi;
 import ai.docling.serve.api.chunk.request.HierarchicalChunkDocumentRequest;
@@ -37,7 +38,7 @@
  * {@link #writeValueAsString(Object)} for serialization and deserialization behavior.
  */
 public abstract class DoclingServeClient implements DoclingServeApi {
-  private static final Logger LOG = Logger.getLogger(DoclingServeClient.class.getName());
+  private static final Logger LOG = LoggerFactory.getLogger(DoclingServeClient.class);
   protected static final URI DEFAULT_BASE_URL = URI.create("http://localhost:5001");
 
   private final URI baseUrl;
@@ -82,7 +83,7 @@ protected DoclingServeClient(DoclingServeClientBuilder builder) {
   protected abstract <T> String writeValueAsString(T value);
 
   protected void logRequest(HttpRequest request) {
-    if (LOG.isLoggable(Level.INFO)) {
+    if (LOG.isInfoEnabled()) {
       var stringBuilder = new StringBuilder();
       stringBuilder.append("\n→ REQUEST: %s %s\n".formatted(request.method(), request.uri()));
       stringBuilder.append("  HEADERS:\n");
@@ -96,7 +97,7 @@ protected void logRequest(HttpRequest request) {
   }
 
   protected void logResponse(HttpResponse<String> response, Optional<String> responseBody) {
-    if (LOG.isLoggable(Level.INFO)) {
+    if (LOG.isInfoEnabled()) {
       var stringBuilder = new StringBuilder();
       stringBuilder.append("\n← RESPONSE: %s\n".formatted(response.statusCode()));
       stringBuilder.append("  HEADERS:\n");
@@ -124,7 +125,7 @@ protected <T> T execute(HttpRequest request, Class<T> expectedValueType) {
     }
     finally {
       long duration = System.currentTimeMillis() - startTime;
-      LOG.info(() -> "Request [%s %s] took %d ms".formatted(request.method(), request.uri(), duration));
+      LOG.info("Request [{} {}] took {}ms", request.method(), request.uri(), duration);
     }
   }
 
@@ -198,7 +199,7 @@ public long contentLength() {
     @Override
     public void subscribe(Subscriber<? super ByteBuffer> subscriber) {
       if (logRequests) {
-        LOG.info(() -> "→ REQUEST BODY: %s".formatted(this.stringContent));
+        LOG.info("→ REQUEST BODY: {}", this.stringContent);
       }
 
       this.delegate.subscribe(subscriber);

docling-testcontainers/build.gradle.kts

@@ -8,7 +8,9 @@ description = "Testcontainers for Docling services"
 dependencies {
   api(platform(libs.testcontainers.bom))
   api("org.testcontainers:testcontainers")
+  api(libs.slf4j.api)
   testImplementation(platform(libs.jackson.bom))
   testImplementation(libs.jackson.databind)
   testImplementation(libs.testcontainers.junit.jupiter)
+  testImplementation(libs.slf4j.simple)
 }

docling-testcontainers/src/main/java/ai/docling/testcontainers/package-info.java

@@ -1,7 +1,9 @@
 package ai.docling.testcontainers.serve;
 
-import java.util.logging.Logger;
+import java.util.Optional;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.testcontainers.containers.GenericContainer;
 import org.testcontainers.containers.wait.strategy.Wait;
 import org.testcontainers.utility.DockerImageName;
@@ -18,7 +20,7 @@
  * health checks for the container.
  */
 public class DoclingServeContainer extends GenericContainer<DoclingServeContainer> {
-  private static final Logger LOG = Logger.getLogger(DoclingServeContainer.class.getName());
+  private static final Logger LOG = LoggerFactory.getLogger(DoclingServeContainer.class);
 
   /**
    * The default container port that docling runs on
@@ -66,21 +68,20 @@ public int getPort() {
    * The URL where to access the Docling Serve API.
    */
   public String getApiUrl() {
-    return "http://" + getHost() + ":" + getPort();
+    return "http://%s:%d".formatted(getHost(), getPort());
   }
 
   /**
    * The URL where to access the Docling Serve UI, if enabled.
    */
-  public String getUiUrl() {
-    return getApiUrl() + "/ui";
+  public Optional<String> getUiUrl() {
+    return this.config.enableUi() ?
+        Optional.of("%s/ui".formatted(getApiUrl())) :
+        Optional.empty();
   }
 
   @Override
   protected void containerIsStarted(InspectContainerResponse containerInfo) {
-    if (config.enableUi()) {
-      LOG.info(() -> "Docling Serve UI: %s".formatted(getUiUrl()));
-    }
+    getUiUrl().ifPresent(url -> LOG.info("Docling Serve UI: {}", url));
   }
-
 }

docling-testcontainers/src/main/java/ai/docling/testcontainers/serve/DoclingServeContainer.java

@@ -30,11 +30,17 @@ private record HealthResponse(String status) {}
         .build()
   );
 
+  @Container
+  private final DoclingServeContainer noUiDoclingContainer = new DoclingServeContainer(
+    DoclingServeContainerConfig.builder()
+        .image(DoclingServeContainerConfig.DOCLING_IMAGE)
+        .enableUi(false)
+        .build()
+  );
+
   @Test
-  void containerAvailable() throws IOException, InterruptedException {
-    var healthRequest = HttpRequest.newBuilder(
-        URI.create("%s/health".formatted(this.doclingContainer.getApiUrl()))
-    )
+  void containerNoUI() throws IOException, InterruptedException {
+    var healthRequest = HttpRequest.newBuilder(URI.create("%s/health".formatted(this.noUiDoclingContainer.getApiUrl())))
         .header("Accept", "application/json")
         .timeout(Duration.ofSeconds(10))
         .GET()
@@ -49,8 +55,31 @@ void containerAvailable() throws IOException, InterruptedException {
         .usingRecursiveComparison()
         .isEqualTo(new HealthResponse("ok"));
 
+    assertThat(this.noUiDoclingContainer.getUiUrl())
+        .isNotNull()
+        .isEmpty();
+  }
+
+  @Test
+  void containerAvailable() throws IOException, InterruptedException {
+    var healthRequest = HttpRequest.newBuilder(URI.create("%s/health".formatted(this.doclingContainer.getApiUrl())))
+        .header("Accept", "application/json")
+        .timeout(Duration.ofSeconds(10))
+        .GET()
+        .build();
+
+    var response = HttpClient.newHttpClient()
+        .send(healthRequest, jsonBodyHandler(DoclingServeContainerAvailableTests.HealthResponse.class))
+        .body();
+
+    assertThat(response)
+        .isNotNull()
+        .usingRecursiveComparison()
+        .isEqualTo(new HealthResponse("ok"));
+
     assertThat(this.doclingContainer.getUiUrl())
-        .isEqualTo(this.doclingContainer.getApiUrl() + "/ui");
+        .get()
+        .isEqualTo("%s/ui".formatted(this.doclingContainer.getApiUrl()));
   }
 
   private static <T> HttpResponse.BodyHandler<T> jsonBodyHandler(Class<T> type) {

docling-testcontainers/src/test/java/ai/docling/testcontainers/serve/DoclingServeContainerAvailableTests.java

@@ -8,6 +8,7 @@ junit = "6.0.1"
 lombok = "1.18.42"
 lombok-gradle = "9.1.0"
 semver4j = "6.0.0"
+slf4j = "2.0.17"
 testcontainers = "2.0.2"
 quarkus = "3.30.2"
 quarkus-github-api = "1.330.0"
@@ -35,6 +36,10 @@ junit-bom = { group = "org.junit", name = "junit-bom", version.ref = "junit" }
 junit-jupiter = { group = "org.junit.jupiter", name = "junit-jupiter" }
 junit-platform = { group = "org.junit.platform", name = "junit-platform-launcher" }
 
+# SLF4j
+slf4j-api = { group = "org.slf4j", name = "slf4j-api", version.ref = "slf4j" }
+slf4j-simple = { group = "org.slf4j", name = "slf4j-simple", version.ref = "slf4j" }
+
 # Testcontainers
 testcontainers-bom = { group = "org.testcontainers", name = "testcontainers-bom", version.ref = "testcontainers"}
 testcontainers-junit-jupiter = { group = "org.testcontainers", name = "testcontainers-junit-jupiter" }