Merge pull request #543 from harti2006/check-class-presence

Check if Tracer is on classpath
zalando · Jan 14, 2019 · 24c8502 · 24c8502
2 parents c509487 + 0e22f59
commit 24c8502
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Showing 2 changed files with 27 additions and 10 deletions.
diff --git a/...spring-boot-starter/src/main/java/org/zalando/riptide/spring/DefaultRiptideRegistrar.java b/...spring-boot-starter/src/main/java/org/zalando/riptide/spring/DefaultRiptideRegistrar.java
@@ -394,15 +394,20 @@ private Optional<String> getHost(final Client client) {
     }
 
     private BeanMetadataElement trace(final String executor) {
-        if (registry.isRegistered("tracer")) {
-            return genericBeanDefinition(TracingExecutors.class)
-                    .setFactoryMethod("preserve")
-                    .addConstructorArgReference(executor)
-                    .addConstructorArgReference("tracer")
-                    .getBeanDefinition();
-        } else {
-            return ref(executor);
-        }
+        final Optional<BeanMetadataElement> result = ifPresent("org.zalando.tracer.concurrent.TracingExecutors",
+                () -> {
+                    if (registry.isRegistered("tracer")) {
+                        return genericBeanDefinition(TracingExecutors.class)
+                                .setFactoryMethod("preserve")
+                                .addConstructorArgReference(executor)
+                                .addConstructorArgReference("tracer")
+                                .getBeanDefinition();
+                    } else {
+                        return null;
+                    }
+                });
+
+        return result.orElseGet(() -> ref(executor));
     }
 
     private String registerHttpClient(final String id, final Client client) {

diff --git a/riptide-spring-boot-starter/src/main/java/org/zalando/riptide/spring/Dependencies.java b/riptide-spring-boot-starter/src/main/java/org/zalando/riptide/spring/Dependencies.java
@@ -1,5 +1,8 @@
 package org.zalando.riptide.spring;
 
+import java.util.Optional;
+import java.util.function.Supplier;
+
 import static org.springframework.util.ClassUtils.getDefaultClassLoader;
 import static org.springframework.util.ClassUtils.isPresent;
 
@@ -10,8 +13,17 @@ private Dependencies() {
     }
 
     static void ifPresent(final String name, final Runnable runnable) {
-        if (isPresent(name, getDefaultClassLoader())) {
+        ifPresent(name, () -> {
             runnable.run();
+            return null;
+        });
+    }
+
+    static <T> Optional<T> ifPresent(final String name, final Supplier<T> supplier) {
+        if (isPresent(name, getDefaultClassLoader())) {
+            return Optional.ofNullable(supplier.get());
+        } else {
+            return Optional.empty();
         }
     }