Add initial ATT tosca checker tool

Addressed license headers and copyright owner issues
Addressed project folder name

Issue-ID: MODELING-7
Change-Id: I150784c5871bb6093ff0a6615639088bc2e0c496
Signed-off-by: Serban Jora <jora@research.att.com>

7 files changed, 734 insertions, 0 deletions

diff --git a/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CachedTarget.java b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CachedTarget.java
new file mode 100644
index 0000000..943891f
--- /dev/null
+++ b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CachedTarget.java
@@ -0,0 +1,99 @@
+/*
+ * 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 java.io.FilterReader;
+import java.io.Reader;
+import java.io.StringReader;
+import java.io.IOException;
+
+import java.net.URI;
+
+import org.springframework.core.io.Resource;
+
+import org.apache.commons.io.input.CharSequenceReader;
+
+import org.onap.tosca.checker.Target;
+
+
+/**
+ * Cache of the target content until invalidation ..
+ */
+public class CachedTarget extends Target {
+
+	private StringBuilder	content;
+
+	public CachedTarget(String theName, URI theResource) {
+		super(theName, theResource);
+	}
+
+	public CachedTarget(Resource theResource) throws IOException {
+		super(theResource.getFilename(), theResource.getURI());
+	}
+
+	protected CachedTarget(CachedTarget theSource) {
+		super(theSource.getName(), theSource.getLocation());
+		if (theSource.hasContent()) {
+			setContent(theSource.getContent());
+		}
+	}
+
+	protected boolean hasContent() {
+		return this.content != null;
+	}
+
+	protected CharSequence getContent() {
+		return this.content == null ? null : this.content;
+	}
+
+	protected void setContent(CharSequence theContent) {
+		this.content = new StringBuilder(theContent);
+	}
+
+	/*
+   */
+	public void invalidate() {
+		this.content = null;
+		setTarget(null);
+	}
+
+	@Override
+	public Reader open() throws IOException {
+		return this.content != null ? 
+						new CharSequenceReader(this.content) : 
+						new FilterReader(super.open()) {
+							{
+								content = new StringBuilder();
+							}
+
+							public int read(char[] cbuf, int off, int len) throws IOException {
+								int res = super.read(cbuf, off, len);
+								if (res > 0)
+									content.append(cbuf, off, res);
+								return res;
+							}
+
+							public int read() throws IOException {
+								int res = super.read();
+								if (res > 0)
+									/* the cast here is troublesome: the original stream had an encoding and this cast has to
+									done with respect to that. */
+									content.append((char)res);
+								return res;
+							}
+	
+						};
+	}
+
+}
+
diff --git a/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/Catalogs.java b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/Catalogs.java
new file mode 100644
index 0000000..e792286
--- /dev/null
+++ b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/Catalogs.java
@@ -0,0 +1,117 @@
+/*
+ * 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 java.net.URI;
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.util.Arrays;
+import java.util.Set;
+import java.util.Map;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Collection;
+import java.util.Collections;
+
+import java.util.stream.Collectors;
+
+import java.util.logging.Logger;
+import java.util.logging.Level;
+
+import javax.annotation.PostConstruct;
+import javax.annotation.PreDestroy;
+
+import org.onap.tosca.checker.Checker;
+import org.onap.tosca.checker.Catalog;
+import org.onap.tosca.checker.Target;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.FatalBeanException;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.support.ResourcePatternResolver;
+import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
+
+import org.springframework.stereotype.Component;
+import org.springframework.context.annotation.Scope;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+@Component("catalogs")
+@Scope("singleton")
+@ConfigurationProperties(prefix="catalogs")
+public class Catalogs implements ApplicationContextAware {
+
+	private static Logger logger = Logger.getLogger(Catalogs.class.getName());
+
+	private ApplicationContext			appCtx;
+	private ResourcePatternResolver	resolver;
+	private Map<String, Catalog> 		catalogs = new HashMap<String, Catalog>();
+
+	public Catalogs() {
+		resolver = new PathMatchingResourcePatternResolver();
+	}
+
+	public void setApplicationContext(ApplicationContext theCtx) throws BeansException {
+    this.appCtx = theCtx;
+	}
+
+	@PostConstruct
+	public void initCatalogs() {
+		logger.entering(getClass().getName(), "initCatalogs");
+		
+		// Done
+		logger.log(Level.INFO, "Catalogs available");
+	}
+
+	@PreDestroy
+	public void cleanupCatalogs() {
+		logger.entering(getClass().getName(), "destroyCatalogs");
+	}
+
+	public Catalog getCatalog(String theName) {
+
+System.out.println("getCatalog: " + theName + ". Known catalogs: " + this.catalogs.keySet());
+
+		return this.catalogs.get(theName);
+	}
+
+	public void setCatalog(String theName, Catalog theCatalog) {
+		this.catalogs.put(theName, theCatalog);
+	}
+
+	public Catalog removeCatalog(String theName) {
+		return this.catalogs.remove(theName);
+	}
+
+	/* configuration interface */
+	public void setCatalogs(Map<String, ?> theCatalogs) {
+			//just look here at the pain of creating a checker ever time ..
+		for (Map.Entry<String, ?> catalogEntry: theCatalogs.entrySet()) {
+			try {
+				Checker checker = new Checker();
+				checker.check((String)catalogEntry.getValue()); 
+				setCatalog(catalogEntry.getKey(), checker.catalog());
+			}
+			catch (Exception x) {
+				throw new FatalBeanException("Failed to add catalog " + catalogEntry.getKey() + " from " + catalogEntry.getValue(), x);
+			}
+		}
+	}
+
+	public Map<String, ?> getCatalogs() {
+		return this.catalogs;
+	}
+
+}
diff --git a/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CheckerController.java b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CheckerController.java
new file mode 100644
index 0000000..cde0323
--- /dev/null
+++ b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/CheckerController.java
@@ -0,0 +1,260 @@
+/*
+ * 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 java.util.logging.Logger;
+import java.util.logging.Level;
+
+import java.util.concurrent.Callable;
+
+import java.net.URI;
+import java.net.URISyntaxException;
+
+import javax.servlet.http.HttpServletRequest; 
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanInitializationException;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+
+import javax.annotation.PostConstruct;
+import javax.annotation.PreDestroy;
+
+import org.onap.tosca.checker.Checker;
+import org.onap.tosca.checker.CheckerException;
+import org.onap.tosca.checker.Report;
+import org.onap.tosca.checker.Catalog;
+import org.onap.tosca.checker.Target;
+import org.onap.tosca.checker.TargetLocator;
+import org.onap.tosca.checker.CommonLocator;
+
+
+
+@RestController
+public class CheckerController implements ApplicationContextAware {
+
+	private static Logger log = Logger.getLogger(CheckerController.class.getName());
+
+	private ApplicationContext			appCtx;
+	@Autowired
+	private Catalogs					catalogs;
+	private Checker						checker;
+	
+	public void setApplicationContext(ApplicationContext theCtx) throws BeansException {
+    this.appCtx = theCtx;
+	}
+
+	/**
+	 * standalone checking, everything will be forgotten
+	 */
+	@RequestMapping(value={"/check_template/"}, method={RequestMethod.POST}, produces={"application/json"})
+	public Report validate(@RequestBody String theTemplate,
+												 HttpServletRequest theRequest) {
+
+System.out.println("Posting unnamed template");
+		CachedTarget target = new CachedTarget("", requestURI(theRequest));
+		target.setContent(theTemplate);
+		((InCatalogLocator)this.checker.getTargetLocator()).setCatalog(null);
+
+		try {
+			this.checker.check(target);
+		}
+		catch (CheckerException cx) {
+			log.log(Level.WARNING, "Failed to check tosca template", cx);
+			target.getReport().add(cx);
+		}
+
+		return target.getReport();
+	}
+
+	/**
+	 * checking with respect to a namespace/catalog but the outcome is forgotten (not added to the catalog)
+	 */
+	@RequestMapping(value={"/check_template/{catalog}"}, method={RequestMethod.POST}, produces={"application/json"})
+	public Report validate(@RequestBody String theTemplate,
+												 @PathVariable(value="catalog") String theCatalog,
+												 HttpServletRequest theRequest) 
+																										throws NoSuchCatalogException {
+
+System.out.println("Posting unnamed template to catalog " + theCatalog);
+		Catalog catalog = this.catalogs.getCatalog(theCatalog);
+		if (catalog == null)
+			throw new NoSuchCatalogException(theCatalog);
+		else
+			((InCatalogLocator)this.checker.getTargetLocator()).setCatalog(catalog);
+
+		CachedTarget target = new CachedTarget("", requestURI(theRequest));
+		target.setContent(theTemplate);
+
+		try {
+			this.checker.check(target, new Catalog(catalog));
+		}
+		catch (CheckerException cx) {
+			log.log(Level.WARNING, "Failed to check tosca template", cx);
+			target.getReport().add(cx);
+		}
+
+		return target.getReport();
+	}
+
+	/**
+	 * checking with respect to a namespace/catalog, the outcome is registered within the catalog 
+	 */	
+	@RequestMapping(value={"/check_template/{catalog}/{name}"}, method={RequestMethod.POST}, produces={"application/json"})
+	public Report validate(@RequestBody String theTemplate,
+												 @PathVariable(value="catalog") String theCatalog,
+												 @PathVariable(value="name") String theName,
+												 HttpServletRequest theRequest)
+																								throws TargetConflictException {
+System.out.println("Posting template named " + theName + " to catalog " + theCatalog);
+		
+		Catalog catalog = this.catalogs.getCatalog(theCatalog);
+		((InCatalogLocator)this.checker.getTargetLocator()).setCatalog(catalog);
+
+		URI targetURI = requestURI(theRequest);
+		if (catalog != null) {
+			if (catalog.getTarget(targetURI) != null)
+				throw new TargetConflictException(theName, theCatalog);
+		}
+
+		CachedTarget target = new CachedTarget("", targetURI);
+		target.setContent(theTemplate);
+
+		try {
+			if (catalog == null)
+				this.checker.check(target);
+			else
+				this.checker.check(target, catalog);
+		}
+		catch (CheckerException cx) {
+			log.log(Level.WARNING, "Failed to check tosca template", cx);
+			target.getReport().add(cx);
+		}
+
+		if (target.getReport().isEmpty() && catalog == null)
+			this.catalogs.setCatalog(theCatalog, checker.catalog());
+
+		return target.getReport();
+	}
+	
+	@RequestMapping(value={"/check_template/{catalog}"}, method={RequestMethod.GET})
+	public ResponseEntity<Void> validate(@PathVariable(value="catalog") String theCatalog) {
+
+		Catalog cat = catalogs.getCatalog(theCatalog);
+		if (cat == null) {
+			return new ResponseEntity(HttpStatus.NOT_FOUND);
+		}
+		
+		return new ResponseEntity(HttpStatus.OK);
+	}
+	
+	@RequestMapping(value={"/check_template/{catalog}"}, method={RequestMethod.DELETE})
+	public ResponseEntity<Void> deleteCatalog(@PathVariable(value="catalog") String theCatalog) {
+
+		Catalog cat = catalogs.removeCatalog(theCatalog);
+		if (cat == null) {
+			return new ResponseEntity(HttpStatus.NOT_FOUND);
+		}
+		
+		return new ResponseEntity(HttpStatus.OK);
+	}
+	
+	@RequestMapping(value={"/check_template/{catalog}/{name}"}, method={RequestMethod.GET})
+	public ResponseEntity<String> retrieve(@PathVariable(value="catalog") String theCatalog,
+												 								 @PathVariable(value="name") String theTemplateName,
+																		 		 HttpServletRequest theRequest) {
+
+		Catalog cat = catalogs.getCatalog(theCatalog);
+		if (cat == null) {
+			return new ResponseEntity(HttpStatus.NOT_FOUND);
+		}
+
+		Target t = cat.getTarget(requestURI(theRequest));
+		if (t == null) {
+			return new ResponseEntity(HttpStatus.NOT_FOUND);
+		}
+
+		return new ResponseEntity("{}", HttpStatus.OK);
+	}
+	
+
+	@PostConstruct
+	public void initController() {
+		log.entering(getClass().getName(), "initCheckerController");
+
+		try {
+			this.checker = new Checker();
+			this.checker.setTargetLocator(new InCatalogLocator());
+		}
+		catch (CheckerException cx) {
+			log.log(Level.WARNING, "CheckerController setup failed", cx);
+			throw new BeanInitializationException("Failed to create a checker", cx);
+		}
+
+		log.log(Level.INFO, "CheckerController started");
+	}
+
+	@PreDestroy
+	public void cleanupController() {
+		log.entering(getClass().getName(), "cleanupCheckerController");
+	}
+
+	private URI requestURI(HttpServletRequest theRequest) {
+		try {
+			return new URI(String.format("%s://%s:%d%s", theRequest.getScheme(),
+																									 theRequest.getServerName(),
+																									 theRequest.getServerPort(),
+																									 theRequest.getRequestURI().toString()));
+		}
+		catch(URISyntaxException urisx) {
+			throw new RuntimeException(urisx);
+		}		
+	}
+
+	/**
+	 */
+	public static class InCatalogLocator extends CommonLocator {
+		
+		private ThreadLocal<Catalog> catalog = new ThreadLocal();
+
+		public InCatalogLocator() {
+		}
+
+		protected void setCatalog(Catalog theCatalog) {
+			this.catalog.set(theCatalog);
+		}
+
+		/** */
+		@Override
+		public Target resolve(String theName) {
+			Target target = null;
+			if (this.catalog.get() != null)
+				target = this.catalog.get()
+															.targets()
+															.stream()
+															.filter(t -> t.getName().equals(theName))
+															.findFirst()
+															.orElse(null);
+			return target == null ?	super.resolve(theName) :	target;
+		}
+	}
+
+}
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);
+    }
+
+}
diff --git a/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/NoSuchCatalogException.java b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/NoSuchCatalogException.java
new file mode 100644
index 0000000..5f0d29d
--- /dev/null
+++ b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/NoSuchCatalogException.java
@@ -0,0 +1,24 @@
+/*
+ * 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.web.bind.annotation.ResponseStatus;
+import org.springframework.http.HttpStatus;
+
+@ResponseStatus(value=HttpStatus.PRECONDITION_FAILED, reason="No such catalog exists in the service")
+public class NoSuchCatalogException extends Exception {
+
+	public NoSuchCatalogException(String theCatalog) {
+  	super("This service instance has not catalog with the name " + theCatalog);
+	}
+}
diff --git a/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/TargetConflictException.java b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/TargetConflictException.java
new file mode 100644
index 0000000..928412f
--- /dev/null
+++ b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/TargetConflictException.java
@@ -0,0 +1,24 @@
+/*
+ * 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.web.bind.annotation.ResponseStatus;
+import org.springframework.http.HttpStatus;
+
+@ResponseStatus(value=HttpStatus.PRECONDITION_FAILED, reason="Same target exists in given catalog")
+public class TargetConflictException extends Exception {
+
+	public TargetConflictException(String theTarget, String theCatalog) {
+  	super("A target with name " + theTarget + " already exists in " + theCatalog);
+	}
+}
diff --git a/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/TemplateChecker.java b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/TemplateChecker.java
new file mode 100644
index 0000000..6227236
--- /dev/null
+++ b/javatoscachecker/service/src/main/java/org/onap/tosca/checker/service/TemplateChecker.java
@@ -0,0 +1,121 @@
+/*
+ * 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 java.net.URI;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.Collections;
+import java.util.logging.Logger;
+import java.util.logging.Level;
+import java.util.concurrent.Callable;
+
+import org.onap.tosca.checker.Target;
+import org.onap.tosca.checker.CommonLocator;
+import org.onap.tosca.checker.Checker;
+import org.onap.tosca.checker.Catalog;
+import org.onap.tosca.checker.Report;
+import org.onap.tosca.checker.CheckerException;
+
+import org.springframework.stereotype.Component;
+import org.springframework.context.annotation.Scope;
+import org.springframework.beans.factory.annotation.Autowired;
+
+/**
+ */
+@Component("templateChecker")
+@Scope("prototype")
+public class TemplateChecker implements Callable<Report> {
+
+	private static Logger log = Logger.getLogger(TemplateChecker.class.getName());
+
+	private	String						template,
+														name,
+														catalog;
+	private URI								uri;
+
+	@Autowired
+	private	Catalogs					catalogs;
+
+	/* */
+	public TemplateChecker(String theTemplate, String theName, String theCatalog, URI theRef) {
+		this.template = theTemplate;
+		this.name = theName;
+		this.catalog = theCatalog;
+		this.uri = theRef;
+	}
+
+	/*
+	 */
+	@Override
+	public Report call() throws Exception {
+
+		if (log.isLoggable(Level.FINEST))
+			log.log(Level.FINEST, "Processing template " + this.template);
+
+		Catalog cat = catalogs.getCatalog(this.catalog);
+		
+		log.log(Level.FINER, "validating template " + this.name + " at " + this.uri + ". Active catalog: " + cat);
+	
+		//because this is a new checker we do not care about the top target name ..	
+		CachedTarget target = new CachedTarget(this.name == null ? "" : this.name, this.uri);
+		target.setContent(this.template);
+		Checker checker = new Checker();
+		checker.setTargetLocator(new InCatalogLocator(cat));
+		try {
+			if (cat != null) {
+				checker.check(target, cat);
+			}
+			else {
+				checker.check(target);
+			}
+		}
+		catch (CheckerException cx) {
+			log.log(Level.WARNING, "Failed to check tosca template", cx);
+			target.getReport().add(cx);
+		}
+
+		//if named template is succesfull and this is a new catalog, register it
+		if (this.name != null && target.getReport().isEmpty() && cat == null) {
+			this.catalogs.setCatalog(this.catalog, checker.catalog());
+		}	
+			
+		return target.getReport().isEmpty() ? null : target.getReport();
+
+	}
+
+
+	public static class InCatalogLocator extends CommonLocator {
+		
+		private Catalog catalog;
+
+		public InCatalogLocator(Catalog theCatalog) {
+			this.catalog = theCatalog;
+		}
+
+		/** */
+		@Override
+		public Target resolve(String theName) {
+			Target target = null;
+			if (this.catalog != null)
+				target = this.catalog.targets()
+															.stream()
+															.filter(t -> t.getName().equals(theName))
+															.findFirst()
+															.orElse(null);
+			return target == null ?	super.resolve(theName) :	target;
+		}
+	}
+}