Commonize framework configs (ReactiveX#460)

Author: Dan Maas

libraries.gradle

@@ -27,6 +27,7 @@ ext {
     micrometerVersion = '1.1.4'
     hibernateValidatorVersion = '6.0.16.Final'
     wiremockVersion = '2.22.0'
+    validationApiVersion = '2.0.1.Final'
     kotlinCoroutinesVersion = '1.2.0'
 
     libraries = [
@@ -114,6 +115,9 @@ ext {
 
             // Groovy
             groovy: "org.codehaus.groovy:groovy-all:2.5.6",
+            
+            // validation
+            validationApi: "javax.validation:validation-api:${validationApiVersion}",
 
             // Kotlin addon
             kotlin_stdlib: "org.jetbrains.kotlin:kotlin-stdlib-jdk8",

resilience4j-core/src/main/java/io/github/resilience4j/core/ClassUtils.java

@@ -0,0 +1,24 @@
+package io.github.resilience4j.core;
+
+import io.github.resilience4j.core.lang.Nullable;
+
+import java.lang.reflect.Constructor;
+import java.util.function.Predicate;
+
+public class ClassUtils {
+
+    @Nullable
+    @SuppressWarnings("unchecked")
+    public static <T> Predicate<T> instantiatePredicateClass(Class<? extends Predicate<T>> clazz) {
+        try {
+            Constructor<? extends Predicate> c = clazz.getConstructor();
+            if (c != null) {
+                return c.newInstance();
+            } else {
+                return null;
+            }
+        } catch (Exception e) {
+            throw new InstantiationException("Unable to create instance of class: " + clazz.getName(), e);
+        }
+    }
+}

resilience4j-core/src/main/java/io/github/resilience4j/core/InstantiationException.java

@@ -0,0 +1,23 @@
+package io.github.resilience4j.core;
+
+public class InstantiationException extends RuntimeException {
+
+    public InstantiationException() {
+    }
+
+    public InstantiationException(String message) {
+        super(message);
+    }
+
+    public InstantiationException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public InstantiationException(Throwable cause) {
+        super(cause);
+    }
+
+    public InstantiationException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
+        super(message, cause, enableSuppression, writableStackTrace);
+    }
+}

resilience4j-core/src/main/java/io/github/resilience4j/core/StringUtils.java

@@ -0,0 +1,11 @@
+package io.github.resilience4j.core;
+
+import io.github.resilience4j.core.lang.Nullable;
+
+public class StringUtils {
+
+    public static boolean isNotEmpty(@Nullable String string) {
+        return string != null && !string.isEmpty();
+    }
+
+}

resilience4j-framework-common/build.gradle

@@ -4,6 +4,9 @@ dependencies {
     compile project(':resilience4j-ratelimiter')
     compile project(':resilience4j-retry')
     compile project(':resilience4j-bulkhead')
+    
+    compile libraries.validationApi
+    compile libraries.hibernate_validator
 }
 
 ext.moduleName='io.github.resilience4j.framework-common'

resilience4j-framework-common/src/main/java/io/github/resilience4j/common/bulkhead/configuration/BulkheadConfigurationProperties.java

@@ -0,0 +1,130 @@
+/*
+ * Copyright 2019 Dan Maas
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.github.resilience4j.common.bulkhead.configuration;
+
+import io.github.resilience4j.core.ConfigurationNotFoundException;
+import io.github.resilience4j.core.StringUtils;
+import io.github.resilience4j.core.lang.Nullable;
+
+import javax.validation.constraints.Min;
+import java.util.HashMap;
+import java.util.Map;
+
+public class BulkheadConfigurationProperties {
+
+    private Map<String, InstanceProperties> instances = new HashMap<>();
+    private Map<String, InstanceProperties> configs = new HashMap<>();
+
+    public io.github.resilience4j.bulkhead.BulkheadConfig createBulkheadConfig(InstanceProperties instanceProperties) {
+        if (StringUtils.isNotEmpty(instanceProperties.getBaseConfig())) {
+            InstanceProperties baseProperties = configs.get(instanceProperties.getBaseConfig());
+            if (baseProperties == null) {
+                throw new ConfigurationNotFoundException(instanceProperties.getBaseConfig());
+            }
+            return buildConfigFromBaseConfig(baseProperties, instanceProperties);
+        }
+        return buildBulkheadConfig(io.github.resilience4j.bulkhead.BulkheadConfig.custom(), instanceProperties);
+    }
+
+    private io.github.resilience4j.bulkhead.BulkheadConfig buildConfigFromBaseConfig(InstanceProperties baseProperties, InstanceProperties instanceProperties) {
+        io.github.resilience4j.bulkhead.BulkheadConfig baseConfig = buildBulkheadConfig(io.github.resilience4j.bulkhead.BulkheadConfig.custom(), baseProperties);
+        return buildBulkheadConfig(io.github.resilience4j.bulkhead.BulkheadConfig.from(baseConfig), instanceProperties);
+    }
+
+    private io.github.resilience4j.bulkhead.BulkheadConfig buildBulkheadConfig(io.github.resilience4j.bulkhead.BulkheadConfig.Builder builder, InstanceProperties instanceProperties) {
+        if (instanceProperties.getMaxConcurrentCalls() != null) {
+            builder.maxConcurrentCalls(instanceProperties.getMaxConcurrentCalls());
+        }
+        if (instanceProperties.getMaxWaitTime() != null) {
+            builder.maxWaitTime(instanceProperties.getMaxWaitTime());
+        }
+        return builder.build();
+    }
+
+    @Nullable
+    public InstanceProperties getBackendProperties(String backend) {
+        return instances.get(backend);
+    }
+
+    public Map<String, InstanceProperties> getInstances() {
+        return instances;
+    }
+
+    /**
+     * For backwards compatibility when setting backends in configuration properties.
+     */
+    public Map<String, InstanceProperties> getBackends() {
+        return instances;
+    }
+
+    public Map<String, InstanceProperties> getConfigs() {
+        return configs;
+    }
+
+    /**
+     * Bulkhead config adapter for integration with Ratpack. {@link #maxWaitTime} should
+     * almost always be set to 0, so the compute threads would not be blocked upon execution.
+     */
+    public static class InstanceProperties {
+
+        @Min(1)
+        private Integer maxConcurrentCalls;
+        @Min(0)
+        private Long maxWaitTime;
+        @Nullable
+        private String baseConfig;
+        @Min(1)
+        private Integer eventConsumerBufferSize = 100;
+
+        public InstanceProperties setMaxConcurrentCalls(Integer maxConcurrentCalls) {
+            this.maxConcurrentCalls = maxConcurrentCalls;
+            return this;
+        }
+
+        public InstanceProperties setMaxWaitTime(Long maxWaitTime) {
+            this.maxWaitTime = maxWaitTime;
+            return this;
+        }
+
+        public InstanceProperties setBaseConfig(String baseConfig) {
+            this.baseConfig = baseConfig;
+            return this;
+        }
+
+        public InstanceProperties eventConsumerBufferSize(Integer eventConsumerBufferSize) {
+            this.eventConsumerBufferSize = eventConsumerBufferSize;
+            return this;
+        }
+
+        public Integer getMaxConcurrentCalls() {
+            return maxConcurrentCalls;
+        }
+
+        public Long getMaxWaitTime() {
+            return maxWaitTime;
+        }
+
+        public String getBaseConfig() {
+            return baseConfig;
+        }
+
+        public Integer getEventConsumerBufferSize() {
+            return eventConsumerBufferSize;
+        }
+
+    }
+
+}

resilience4j-framework-common/src/main/java/io/github/resilience4j/bulkhead/monitoring/endpoint/BulkheadEndpointResponse.java renamed to resilience4j-framework-common/src/main/java/io/github/resilience4j/common/bulkhead/monitoring/endpoint/BulkheadEndpointResponse.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package io.github.resilience4j.bulkhead.monitoring.endpoint;
+package io.github.resilience4j.common.bulkhead.monitoring.endpoint;
 
 import java.util.List;
 

resilience4j-framework-common/src/main/java/io/github/resilience4j/bulkhead/monitoring/endpoint/BulkheadEventDTO.java renamed to resilience4j-framework-common/src/main/java/io/github/resilience4j/common/bulkhead/monitoring/endpoint/BulkheadEventDTO.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package io.github.resilience4j.bulkhead.monitoring.endpoint;
+package io.github.resilience4j.common.bulkhead.monitoring.endpoint;
 
 import io.github.resilience4j.bulkhead.event.BulkheadEvent;
 

resilience4j-framework-common/src/main/java/io/github/resilience4j/bulkhead/monitoring/endpoint/BulkheadEventDTOFactory.java renamed to resilience4j-framework-common/src/main/java/io/github/resilience4j/common/bulkhead/monitoring/endpoint/BulkheadEventDTOFactory.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package io.github.resilience4j.bulkhead.monitoring.endpoint;
+package io.github.resilience4j.common.bulkhead.monitoring.endpoint;
 
 import io.github.resilience4j.bulkhead.event.BulkheadEvent;
 

resilience4j-framework-common/src/main/java/io/github/resilience4j/bulkhead/monitoring/endpoint/BulkheadEventsEndpointResponse.java renamed to resilience4j-framework-common/src/main/java/io/github/resilience4j/common/bulkhead/monitoring/endpoint/BulkheadEventsEndpointResponse.java

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package io.github.resilience4j.bulkhead.monitoring.endpoint;
+package io.github.resilience4j.common.bulkhead.monitoring.endpoint;
 
 import java.util.List;
 

resilience4j-framework-common/src/main/java/io/github/resilience4j/circuitbreaker/monitoring/endpoint/package-info.java renamed to resilience4j-framework-common/src/main/java/io/github/resilience4j/common/bulkhead/monitoring/endpoint/package-info.java

@@ -18,7 +18,7 @@
  */
 @NonNullApi
 @NonNullFields
-package io.github.resilience4j.circuitbreaker.monitoring.endpoint;
+package io.github.resilience4j.common.bulkhead.monitoring.endpoint;
 
 import io.github.resilience4j.core.lang.NonNullApi;
 import io.github.resilience4j.core.lang.NonNullFields;