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Diffstat (limited to 'javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CheckerEngine.java')
| -rw-r--r-- | javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CheckerEngine.java | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CheckerEngine.java b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CheckerEngine.java new file mode 100644 index 0000000..24c168b --- /dev/null +++ b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CheckerEngine.java @@ -0,0 +1,89 @@ +/* + * Copyright (c) 2017 <AT&T>. All rights reserved. + * =================================================================== + * 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 org.onap.tosca.checker.service; + +import org.springframework.boot.SpringApplication; +import org.springframework.boot.autoconfigure.SpringBootApplication; +import org.springframework.context.annotation.ImportResource; +//import org.springframework.context.ApplicationContext; +import org.springframework.context.support.ClassPathXmlApplicationContext; +import org.springframework.scheduling.annotation.EnableScheduling; +import org.springframework.core.env.ConfigurableEnvironment; +import org.springframework.context.ConfigurableApplicationContext; +import org.springframework.beans.factory.support.DefaultListableBeanFactory; + +/** + * This is the entry point of the validation engine. + * The maven build script packages the application as a 'all-in-one' jar. As such, there are 2 ways to start + * the application: + * java -jar ASC-Validator-some_version.jar + * or + * java -cp some_path/ASC-Validator-some_version.jar org.springframework.boot.loader.JarLauncher + * + * The second version is important because it gets around the known java issue/bug of not being able to specify + * additional classpath elements when using the '-jar' option (additional '-cp' options are being ignored). This + * version allows to add to the classpath the location of additional configuration. + * + * The approach in packaging the application was to include in the (all-in-one) package the known configurations + * (such that it is as easy as possible to install/setup/start the applications) while still having the possibility + * of re-specifying (some of) the configuration. + * + * All out beans are specified within 'checker.xml'; use spring profiles to distinguish between the + * configurations for each environment. + * <beans profile="dev"> .. </beans> + * <beans profile="ist"> .. </beans> + * + * The default configuration is for the development environment. In order to run a particular configuration we use the + * spring.profiles.active environment variable, as in: + * java -Dspring.profiles.active=ist -jar some_path/ASC-Validator-Service-some_version.jar + * or + * java -Dspring.profiles.active=ist -cp some_path/ASC-Validator-some_version.jar org.springframework.boot.loader.JarLauncher + * + * Note: we can have a 'common' profile to be always activated that includes those bean specifications least likely to + * change. + * + * Resource reference syntax: + * classpath*:validator.xml + * vs + * classpath:validator.xml + * + * In the first case we direct the bean loader to find *ALL* validator.xml files in the classpath and merge them + * (merge the parts for the active profile(s)) + * In the second case we instruct the bean loader to locate the *FIRST* validator.xml file and process it. All others + * (validator.xml) files will be ignored. + * + * Overwriting pre-packaged bean configuration: + * The first version would theoretically allow us to specify beans configuration deltas (with respect to the + * pre-packaged version). In practice I did not manage to have this approach working reliably: it relies on a + * deterministic order of classpath processing and on overriding some of the spring framework defaults (in not so + * obvious ways, bean indexing for example). + * Currently we enable the second option, i.e. one has to provide a FULL alternative bean configuration. This + * alternative configuration can be specified as overwriting an existing profile or as an entirely new profile. + * (when using alternative profiles the resourcec reference syntax is irrelevant ..) + */ + +@SpringBootApplication(scanBasePackages={"org.onap.tosca.checker.service"}) +@ImportResource({"classpath:${beans.config?:checker}.xml"}) +@EnableScheduling +public class CheckerEngine +{ + + public CheckerEngine() { + } + + public static void main(String theArgs[]) { + SpringApplication sapp = new SpringApplication(CheckerEngine.class); + ConfigurableApplicationContext ctx = sapp.run(theArgs); + } + +} |