feat(config): Resolve configfiles using a custom PropertySource (spin…

…naker#370)

kork-config/kork-config.gradle

@@ -7,6 +7,8 @@ dependencies {
   implementation "commons-io:commons-io"
   implementation "org.apache.commons:commons-lang3"
 
+  api project(':kork-secrets')
+
   api "org.springframework.cloud:spring-cloud-context"
   api "org.springframework.cloud:spring-cloud-config-server"
 

kork-config/src/main/java/com/netflix/spinnaker/kork/configserver/CloudConfigApplicationListener.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2019 Pivotal, Inc.
+ *
+ * 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 com.netflix.spinnaker.kork.configserver;
+
+import com.netflix.spinnaker.kork.secrets.SecretAwarePropertySource;
+import org.springframework.boot.context.event.ApplicationPreparedEvent;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.env.PropertySource;
+
+public class CloudConfigApplicationListener
+    implements ApplicationListener<ApplicationPreparedEvent> {
+  private static final String APPLICATION_CONFIG_PROPERTY_SOURCE_PREFIX = "applicationConfig:";
+  private static final String CONFIG_SERVER_PROPERTY_SOURCE_NAME = "bootstrapProperties";
+
+  @Override
+  public void onApplicationEvent(ApplicationPreparedEvent event) {
+    ConfigurableApplicationContext context = event.getApplicationContext();
+    ConfigurableEnvironment environment = context.getEnvironment();
+
+    for (PropertySource propertySource : environment.getPropertySources()) {
+      if (shouldWrap(propertySource)) {
+        CloudConfigAwarePropertySource wrapper =
+            new CloudConfigAwarePropertySource(propertySource, context);
+        environment.getPropertySources().replace(propertySource.getName(), wrapper);
+      }
+    }
+  }
+
+  private boolean shouldWrap(PropertySource propertySource) {
+    return (propertySource.getName().startsWith(APPLICATION_CONFIG_PROPERTY_SOURCE_PREFIX)
+            || propertySource.getName().equals(CONFIG_SERVER_PROPERTY_SOURCE_NAME))
+        && !((propertySource instanceof CloudConfigAwarePropertySource)
+            || (propertySource instanceof SecretAwarePropertySource));
+  }
+}

kork-config/src/main/java/com/netflix/spinnaker/kork/configserver/CloudConfigAwarePropertySource.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2019 Pivotal, Inc.
+ *
+ * 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 com.netflix.spinnaker.kork.configserver;
+
+import org.springframework.beans.BeansException;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.env.EnumerablePropertySource;
+import org.springframework.core.env.PropertySource;
+
+public class CloudConfigAwarePropertySource extends EnumerablePropertySource<PropertySource> {
+  private final ConfigurableApplicationContext context;
+  private CloudConfigResourceService resourceService;
+
+  CloudConfigAwarePropertySource(PropertySource source, ConfigurableApplicationContext context) {
+    super(source.getName(), source);
+    this.context = context;
+  }
+
+  @Override
+  public Object getProperty(String name) {
+    Object value = source.getProperty(name);
+    if (value instanceof String) {
+      String stringValue = (String) value;
+      if (CloudConfigResourceService.isCloudConfigResource(stringValue)) {
+        resolveResourceService(stringValue);
+        value = resourceService.getLocalPath(stringValue);
+      }
+    }
+    return value;
+  }
+
+  private void resolveResourceService(String path) {
+    if (resourceService == null) {
+      try {
+        resourceService = context.getBean(CloudConfigResourceService.class);
+      } catch (BeansException e) {
+        throw new ConfigFileLoadingException(
+            "Config Server repository not configured for resource \"" + path + "\"");
+      }
+    }
+  }
+
+  @Override
+  public String[] getPropertyNames() {
+    if (source instanceof EnumerablePropertySource) {
+      return ((EnumerablePropertySource) source).getPropertyNames();
+    } else {
+      return new String[0];
+    }
+  }
+}

kork-config/src/main/java/com/netflix/spinnaker/kork/configserver/CloudConfigResourceService.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright 2019 Pivotal, Inc.
+ *
+ * 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 com.netflix.spinnaker.kork.configserver;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import org.apache.commons.io.IOUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.cloud.config.environment.Environment;
+import org.springframework.cloud.config.server.environment.EnvironmentRepository;
+import org.springframework.cloud.config.server.resource.NoSuchResourceException;
+import org.springframework.cloud.config.server.resource.ResourceRepository;
+import org.springframework.cloud.config.server.support.EnvironmentPropertySource;
+import org.springframework.context.EnvironmentAware;
+import org.springframework.core.env.StandardEnvironment;
+import org.springframework.core.io.Resource;
+
+public class CloudConfigResourceService implements EnvironmentAware {
+  private static final String CONFIG_SERVER_RESOURCE_PREFIX = "configserver:";
+
+  private final ResourceRepository resourceRepository;
+  private final EnvironmentRepository environmentRepository;
+
+  @Value("${spring.application.name:application}")
+  private String applicationName = "application";
+
+  private String profiles;
+
+  public CloudConfigResourceService() {
+    this.resourceRepository = null;
+    this.environmentRepository = null;
+  }
+
+  public CloudConfigResourceService(
+      ResourceRepository resourceRepository, EnvironmentRepository environmentRepository) {
+    this.resourceRepository = resourceRepository;
+    this.environmentRepository = environmentRepository;
+  }
+
+  public String getLocalPath(String path) {
+    String contents = retrieveFromConfigServer(path);
+    return ConfigFileUtils.writeToTempFile(contents, getResourceName(path));
+  }
+
+  private String retrieveFromConfigServer(String path) {
+    if (resourceRepository == null || environmentRepository == null) {
+      throw new ConfigFileLoadingException(
+          "Config Server repository not configured for resource \"" + path + "\"");
+    }
+
+    try {
+      String fileName = getResourceName(path);
+      Resource resource =
+          this.resourceRepository.findOne(applicationName, profiles, null, fileName);
+      try (InputStream inputStream = resource.getInputStream()) {
+        Environment environment =
+            this.environmentRepository.findOne(applicationName, profiles, null);
+
+        String text = IOUtils.toString(inputStream, StandardCharsets.UTF_8);
+        StandardEnvironment preparedEnvironment =
+            EnvironmentPropertySource.prepareEnvironment(environment);
+        return EnvironmentPropertySource.resolvePlaceholders(preparedEnvironment, text);
+      }
+    } catch (NoSuchResourceException e) {
+      throw new ConfigFileLoadingException(
+          "The resource \"" + path + "\" was not found in config server", e);
+    } catch (IOException e) {
+      throw new ConfigFileLoadingException(
+          "Exception reading config server resource \"" + path + "\"", e);
+    }
+  }
+
+  private String getResourceName(String path) {
+    return path.substring(CONFIG_SERVER_RESOURCE_PREFIX.length());
+  }
+
+  @Override
+  public void setEnvironment(org.springframework.core.env.Environment environment) {
+    profiles = StringUtils.join(environment.getActiveProfiles(), ",");
+  }
+
+  public static boolean isCloudConfigResource(String path) {
+    return path.startsWith(CONFIG_SERVER_RESOURCE_PREFIX);
+  }
+}

kork-config/src/main/java/com/netflix/spinnaker/kork/configserver/ConfigFileLoadingException.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2019 Pivotal, Inc.
+ *
+ * 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 com.netflix.spinnaker.kork.configserver;
+
+public class ConfigFileLoadingException extends RuntimeException {
+  public ConfigFileLoadingException(String message) {
+    super(message);
+  }
+
+  public ConfigFileLoadingException(String message, Throwable cause) {
+    super(message, cause);
+  }
+
+  public ConfigFileLoadingException(Throwable cause) {
+    super(cause);
+  }
+}