From c53b821c85ba5ba115d8e6848c7ad881f64b0666 Mon Sep 17 00:00:00 2001 From: Kenji Nagahashi Date: Tue, 28 May 2013 13:28:37 -0700 Subject: [PATCH 1/3] FIX: 73f58dc56a broke XML variant of scripting console response, and will produce incompatible structure (extra nesting with scriptExec element). moved ScriptExecution code to ScriptModel, which is now a bean, not Map. XmlMarshaller is extended to support simple JavaBeans to XML marshalling, borrowing annotation classes from javax.xml. --- .../crawler/restlet/ScriptResource.java | 117 ++------------- .../crawler/restlet/XmlMarshaller.java | 97 +++++++++++++ .../crawler/restlet/models/ScriptModel.java | 135 +++++++++++++++--- .../org/archive/crawler/restlet/Script.ftl | 21 +-- 4 files changed, 236 insertions(+), 134 deletions(-) diff --git a/engine/src/main/java/org/archive/crawler/restlet/ScriptResource.java b/engine/src/main/java/org/archive/crawler/restlet/ScriptResource.java index 6d53f434..5f3da976 100644 --- a/engine/src/main/java/org/archive/crawler/restlet/ScriptResource.java +++ b/engine/src/main/java/org/archive/crawler/restlet/ScriptResource.java @@ -20,8 +20,6 @@ package org.archive.crawler.restlet; import java.io.IOException; -import java.io.PrintWriter; -import java.io.StringWriter; import java.io.Writer; import java.util.Collection; import java.util.Collections; @@ -31,14 +29,11 @@ import java.util.LinkedList; import java.util.List; import java.util.Map; -import javax.script.Bindings; import javax.script.ScriptEngine; import javax.script.ScriptEngineFactory; import javax.script.ScriptEngineManager; -import javax.script.ScriptException; import org.apache.commons.lang.StringUtils; -import org.archive.crawler.framework.BeanLookupBindings; import org.archive.crawler.restlet.models.ScriptModel; import org.archive.crawler.restlet.models.ViewModel; import org.restlet.Context; @@ -52,7 +47,6 @@ import org.restlet.resource.Representation; import org.restlet.resource.ResourceException; import org.restlet.resource.Variant; import org.restlet.resource.WriterRepresentation; -import org.springframework.context.ApplicationContext; import freemarker.template.Configuration; import freemarker.template.ObjectWrapper; @@ -84,7 +78,6 @@ public class ScriptResource extends JobRelatedResource { } }); } - ScriptExecution scriptExec = null; protected String chosenEngine = FACTORIES.isEmpty() ? "" : FACTORIES.getFirst().getNames().get(0); private Configuration _templateConfiguration; @@ -106,92 +99,8 @@ public class ScriptResource extends JobRelatedResource { public Configuration getTemplateConfiguration(){ return _templateConfiguration; } - - /** - * JavaBean that packages script, its execution and the result. - * - * TODO: the script could create an object that persists and retains a - * reference to the Bindings. by encapsulating this way, I've made it - * a bit more difficult? we could {@code eng} and {@code script} arguments - * to execute() method. - */ - public static class ScriptExecution { - private ScriptEngine eng; - private ApplicationContext appCtx; - private Bindings bindings; - private String script; - - private StringWriter rawString; - private StringWriter htmlString; - private Throwable exception; - private int linesExecuted; - - public ScriptExecution(ScriptEngine eng, ApplicationContext appCtx, String script) { - this.eng = eng; - this.appCtx = appCtx; - this.bindings = new BeanLookupBindings(appCtx); - this.script = script; - if (StringUtils.isBlank(this.script)) { - this.script = ""; - } - this.rawString = new StringWriter(); - this.htmlString = new StringWriter(); - } - public void bind(String name, Object obj) { - bindings.put(name, obj); - } - public Object unbind(String name) { - return bindings.remove(name); - } - public void execute() { - PrintWriter rawOut = new PrintWriter(rawString); - PrintWriter htmlOut = new PrintWriter(htmlString); - bind("rawOut", rawOut); - bind("htmlOut", htmlOut); - bind("appCtx", appCtx); - try { - eng.eval(script, bindings); - // TODO: should count with RE rather than creating String[]? - linesExecuted = script.split("\r?\n").length; - } catch (ScriptException ex) { - Throwable cause = ex.getCause(); - exception = cause != null ? cause : ex; - } catch (RuntimeException ex) { - exception = ex; - } finally { - rawOut.flush(); - htmlOut.flush(); - // TODO: are these really necessary? - unbind("rawOut"); - unbind("htmlOut"); - unbind("appCtx"); - } - } - public boolean isFailure() { - return exception != null; - } - public String getStackTrace() { - if (exception == null) return ""; - StringWriter s = new StringWriter(); - exception.printStackTrace(new PrintWriter(s)); - return s.toString(); - } - public Throwable getException() { - return exception; - } - public int getLinesExecuted() { - return linesExecuted; - } - public String getRawOutput() { - return rawString.toString(); - } - public String getHtmlOutput() { - return htmlString.toString(); - } - public String getScript() { - return script; - } - } + + private ScriptModel scriptModel; @Override public void acceptRepresentation(Representation entity) throws ResourceException { @@ -204,12 +113,10 @@ public class ScriptResource extends JobRelatedResource { ScriptEngine eng = MANAGER.getEngineByName(chosenEngine); - scriptExec = new ScriptExecution(eng, cj.getJobContext(), script); - scriptExec.bind("job", cj); - scriptExec.bind("scriptResource", this); - scriptExec.execute(); - scriptExec.unbind("job"); - scriptExec.unbind("scriptResource"); + scriptModel = makeDataModel(); + scriptModel.bind("scriptResource", this); + scriptModel.execute(eng, script); + scriptModel.unbind("scriptResource"); //TODO: log script, results somewhere; job log INFO? @@ -217,11 +124,14 @@ public class ScriptResource extends JobRelatedResource { } public Representation represent(Variant variant) throws ResourceException { + if (scriptModel == null) { + scriptModel = makeDataModel(); + } Representation representation; if (variant.getMediaType() == MediaType.APPLICATION_XML) { representation = new WriterRepresentation(MediaType.APPLICATION_XML) { public void write(Writer writer) throws IOException { - XmlMarshaller.marshalDocument(writer,"script", makeDataModel()); + XmlMarshaller.marshalDocument(writer,"script", scriptModel); } }; } else { @@ -262,10 +172,9 @@ public class ScriptResource extends JobRelatedResource { } Reference baseRefRef = new Reference(baseRef); - ScriptModel model = new ScriptModel(cj.getShortName(), + ScriptModel model = new ScriptModel(cj, new Reference(baseRefRef, "..").getTargetRef().toString(), - getAvailableScriptEngines(), - scriptExec); + getAvailableScriptEngines()); return model; } @@ -284,7 +193,7 @@ public class ScriptResource extends JobRelatedResource { viewModel.put("cssRef", getStylesheetRef()); viewModel.put("staticRef", getStaticRef("")); viewModel.put("baseResourceRef",getRequest().getRootRef().toString()+"/engine/static/"); - viewModel.put("model",makeDataModel()); + viewModel.put("model", scriptModel); viewModel.put("selectedEngine", chosenEngine); try { diff --git a/engine/src/main/java/org/archive/crawler/restlet/XmlMarshaller.java b/engine/src/main/java/org/archive/crawler/restlet/XmlMarshaller.java index 88f94218..e933ec7a 100644 --- a/engine/src/main/java/org/archive/crawler/restlet/XmlMarshaller.java +++ b/engine/src/main/java/org/archive/crawler/restlet/XmlMarshaller.java @@ -19,10 +19,23 @@ package org.archive.crawler.restlet; +import java.beans.BeanInfo; +import java.beans.IntrospectionException; +import java.beans.Introspector; +import java.beans.PropertyDescriptor; import java.io.IOException; import java.io.Writer; +import java.lang.reflect.Method; +import java.util.Arrays; +import java.util.Comparator; +import java.util.HashMap; import java.util.Map; +import javax.xml.bind.annotation.XmlRootElement; +import javax.xml.bind.annotation.XmlTransient; +import javax.xml.bind.annotation.XmlType; + +import org.apache.commons.lang.StringUtils; import org.restlet.util.XmlWriter; import org.xml.sax.SAXException; @@ -90,6 +103,88 @@ public class XmlMarshaller { } } } + /** + * sort PropertyDescriptors according to propOrder. + * properties listed in propOrder come first, in the order they are listed, and + * then come remaining unlisted properties, in arbitrary order (likely alphabetical). + * this semantics is rather relaxed compared to original JAXB semantics, where props + * and propOrder must be the same set (except for those marked XmlTransient). + * @param props PropertyDescriptor array to be sorted in-place. + * @param propOrder list of property names in order of desired appearance. + */ + protected static void orderProperties(PropertyDescriptor[] props, final String[] propOrder) { + if (propOrder == null || propOrder.length == 0) return; + final Map order = new HashMap(); + for (int i = 0; i < propOrder.length; i++) { + order.put(propOrder[i], i); + } + final Integer LAST = Integer.valueOf(propOrder.length); + Arrays.sort(props, new Comparator() { + @Override + public int compare(PropertyDescriptor o1, PropertyDescriptor o2) { + Integer c1 = order.get(o1.getName()); + Integer c2 = order.get(o2.getName()); + return (c1 != null ? c1 : LAST).compareTo(c2 != null ? c2 : LAST); + } + }); + } + /** + * test if {@code obj} has {@link XmlRootElement} annotation. + * to avoid unexpected side effects, objects are mapped to nested XML structure + * only when its class has {@link XmlRootElement} annotation. + * note semantics is slightly different from JAXB - just borrowing XmlRootElement + * as substitute of XmlElement, because Map entry cannot be annotated. + * @param obj object to test + * @return true if obj's class has XmlRootElement annotation. + */ + protected static boolean marshalAsElement(Object obj) { + XmlRootElement ann = obj.getClass().getAnnotation(XmlRootElement.class); + return ann != null; + } + /** + * generate nested XML structure for a bean {@code obj}. enclosing element + * will not be generated if {@code key} is empty. each readable JavaBeans property + * is mapped to an nested element named after its name. Those properties + * annotated with {@link XmlTransient} are ignored. + * @param xmlWriter XmlWriter + * @param key name of enclosing element + * @param obj bean + * @throws SAXException + */ + protected static void marshalBean(XmlWriter xmlWriter, String key, Object obj) throws SAXException { + if (!StringUtils.isEmpty(key)) + xmlWriter.startElement(key); + try { + BeanInfo beanInfo = Introspector.getBeanInfo(obj.getClass(), Object.class); + PropertyDescriptor[] props = beanInfo.getPropertyDescriptors(); + XmlType xmlType = obj.getClass().getAnnotation(XmlType.class); + if (xmlType != null) { + String[] propOrder = xmlType.propOrder(); + if (propOrder != null) { + // TODO: should cache this sorted version? + orderProperties(props, propOrder); + } + } + for (PropertyDescriptor prop : props) { + Method m = prop.getReadMethod(); + if (m == null || m.getAnnotation(XmlTransient.class) != null) + continue; + try { + Object propValue = m.invoke(obj); + if (propValue != null && !"".equals(propValue)) { + marshal(xmlWriter, prop.getName(), propValue); + } + } catch (Exception ex) { + // generate empty element, for now. generate comment? + xmlWriter.emptyElement(prop.getName()); + } + } + } catch (IntrospectionException ex) { + // ignored, for now. + } + if (!StringUtils.isEmpty(key)) + xmlWriter.endElement(key); + } protected static void marshal(XmlWriter xmlWriter, String key, Object value) throws SAXException { if (value == null) { @@ -98,6 +193,8 @@ public class XmlMarshaller { marshal(xmlWriter, key, (Map) value); } else if (value instanceof Iterable) { marshal(xmlWriter, key, (Iterable) value); + } else if (marshalAsElement(value)) { + marshalBean(xmlWriter, key, value); } else { xmlWriter.dataElement(key, value.toString()); } diff --git a/engine/src/main/java/org/archive/crawler/restlet/models/ScriptModel.java b/engine/src/main/java/org/archive/crawler/restlet/models/ScriptModel.java index f7ef1c9c..e748ed76 100644 --- a/engine/src/main/java/org/archive/crawler/restlet/models/ScriptModel.java +++ b/engine/src/main/java/org/archive/crawler/restlet/models/ScriptModel.java @@ -1,28 +1,51 @@ package org.archive.crawler.restlet.models; +import java.io.PrintWriter; +import java.io.StringWriter; import java.util.Collection; import java.util.LinkedHashMap; import java.util.LinkedList; import java.util.List; import java.util.Map; -import org.archive.crawler.restlet.ScriptResource.ScriptExecution; +import javax.script.Bindings; +import javax.script.ScriptEngine; +import javax.script.ScriptException; +import javax.xml.bind.annotation.XmlRootElement; +import javax.xml.bind.annotation.XmlType; -@SuppressWarnings("serial") -public class ScriptModel extends LinkedHashMap { +import org.archive.crawler.framework.BeanLookupBindings; +import org.archive.crawler.framework.CrawlJob; - public ScriptModel(String crawlJobShortName, String crawlJobUrl, - Collection> scriptEngines, - ScriptExecution scriptExec) {// int linesExecuted, Exception - // exception, String rawOutput, - // String htmlOutput){ - super(); - this.put("crawlJobUrl",crawlJobUrl); - this.put("crawlJobShortName", crawlJobShortName); - this.put("availableScriptEngines", scriptEngines); - - if (scriptExec != null) - this.put("scriptExec", scriptExec); +@XmlRootElement(name="script") +@XmlType(propOrder={ + "crawlJobUrl", "crawlJobShortName", "availableScriptEngines", + "script", "linesExecuted", "exception", "rawOutput", "htmlOutput", + "availableGlobalVariables" +}) +public class ScriptModel { + private CrawlJob cj; + private String crawlJobUrl; + private Collection> availableScriptEngines; + + //private ApplicationContext appCtx; + private ScriptEngine eng; + private String script; + private Bindings bindings; + + private StringWriter rawString; + private StringWriter htmlString; + private Throwable exception; + private int linesExecuted; + + private List> availableGlobalVariables; + + public ScriptModel(CrawlJob cj, + String crawlJobUrl, + Collection> scriptEngines) { + this.crawlJobUrl = crawlJobUrl; + this.cj = cj; + this.availableScriptEngines = scriptEngines; List> vars = new LinkedList>(); Map var; @@ -51,6 +74,86 @@ public class ScriptModel extends LinkedHashMap { var.put("variable", "scriptResource"); var.put("description", "the ScriptResource implementing this page, which offers utility methods"); vars.add(var); - this.put("availableGlobalVariables", vars); + + this.availableGlobalVariables = vars; + + this.bindings = new BeanLookupBindings(this.cj.getJobContext()); + this.script = ""; + } + + public void bind(String name, Object obj) { + bindings.put(name, obj); + } + public Object unbind(String name) { + return bindings.remove(name); + } + public void execute(ScriptEngine eng, String script) { + // TODO: update through setter rather than passing as method arguments? + this.eng = eng; + this.script = script; + + bind("job", cj); + rawString = new StringWriter(); + htmlString = new StringWriter(); + PrintWriter rawOut = new PrintWriter(rawString); + PrintWriter htmlOut = new PrintWriter(htmlString); + bind("rawOut", rawOut); + bind("htmlOut", htmlOut); + bind("appCtx", cj.getJobContext()); + try { + this.eng.eval(this.script, bindings); + // TODO: should count with RE rather than creating String[]? + linesExecuted = script.split("\r?\n").length; + } catch (ScriptException ex) { + Throwable cause = ex.getCause(); + exception = cause != null ? cause : ex; + } catch (RuntimeException ex) { + exception = ex; + } finally { + rawOut.flush(); + htmlOut.flush(); + // TODO: are these really necessary? + unbind("rawOut"); + unbind("htmlOut"); + unbind("appCtx"); + unbind("job"); + } + } + public boolean isFailure() { + return exception != null; + } + public String getStackTrace() { + if (exception == null) return ""; + StringWriter s = new StringWriter(); + exception.printStackTrace(new PrintWriter(s)); + return s.toString(); + } + public Throwable getException() { + return exception; + } + public int getLinesExecuted() { + return linesExecuted; + } + public String getRawOutput() { + return rawString != null ? rawString.toString() : ""; + } + public String getHtmlOutput() { + return htmlString != null ? htmlString.toString() : ""; + } + public String getScript() { + return script; + } + + public String getCrawlJobShortName() { + return cj.getShortName(); + } + public Collection> getAvailableScriptEngines() { + return availableScriptEngines; + } + public List> getAvailableGlobalVariables() { + return availableGlobalVariables; + } + public String getCrawlJobUrl() { + return crawlJobUrl; } } diff --git a/engine/src/main/resources/org/archive/crawler/restlet/Script.ftl b/engine/src/main/resources/org/archive/crawler/restlet/Script.ftl index 3ccbb385..9201c258 100644 --- a/engine/src/main/resources/org/archive/crawler/restlet/Script.ftl +++ b/engine/src/main/resources/org/archive/crawler/restlet/Script.ftl @@ -15,29 +15,26 @@

Execute script for job ${model.crawlJobShortName}

- - <#if model.scriptExec??> - <#if (model.scriptExec.linesExecuted > 0)> - ${model.scriptExec.linesExecuted} ${(model.scriptExec.linesExecuted>1)?string("lines","line")} executed + <#if (model.linesExecuted > 0)> + ${model.linesExecuted} ${(model.linesExecuted>1)?string("lines","line")} executed - <#if model.scriptExec.failure> - 
${model.scriptExec.stackTrace}
+	<#if model.failure>
+	
${model.stackTrace}
 	

 	
-	<#assign htmlOutput=model.scriptExec.htmlOutput>
+	<#assign htmlOutput=model.htmlOutput>
 	<#if (htmlOutput?length > 0)>
 	
htmlOut
 	${htmlOutput}
 	

 	
-	<#assign rawOutput=model.scriptExec.rawOutput>
+	<#assign rawOutput=model.rawOutput>
 	<#if (rawOutput?length > 0)>
 	
rawOutput
 		
${rawOutput}
 		

 	

 	
-	
 
 	

 		
@@ -46,7 +43,7 @@
 			 selected="selected" value="${scriptEngine.engine}">${scriptEngine.language}
 			
 		
-		
+		
 		
 	
 	The script will be executed in an engine preloaded
@@ -69,7 +66,3 @@
 	
 
 
-
-
-
-

From 3a54600a79a95eb09479d88ef57e51a4c32dce76 Mon Sep 17 00:00:00 2001
From: Kenji Nagahashi 
Date: Wed, 29 May 2013 12:03:49 -0700
Subject: [PATCH 2/3] ADD unit test for XmlMarshaller

---
 .../crawler/restlet/XmlMarshallerTest.java    | 112 ++++++++++++++++++
 1 file changed, 112 insertions(+)
 create mode 100644 engine/src/test/java/org/archive/crawler/restlet/XmlMarshallerTest.java

diff --git a/engine/src/test/java/org/archive/crawler/restlet/XmlMarshallerTest.java b/engine/src/test/java/org/archive/crawler/restlet/XmlMarshallerTest.java
new file mode 100644
index 00000000..ac44ac2a
--- /dev/null
+++ b/engine/src/test/java/org/archive/crawler/restlet/XmlMarshallerTest.java
@@ -0,0 +1,112 @@
+/**
+ * 
+ */
+package org.archive.crawler.restlet;
+
+import java.io.StringWriter;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import javax.xml.bind.annotation.XmlRootElement;
+import javax.xml.bind.annotation.XmlType;
+
+import junit.framework.TestCase;
+
+/**
+ * @author kenji
+ *
+ */
+public class XmlMarshallerTest extends TestCase {
+
+    /* (non-Javadoc)
+     * @see junit.framework.TestCase#setUp()
+     */
+    protected void setUp() throws Exception {
+        super.setUp();
+    }
+    
+    /**
+     * Map with nested Map
+     * @throws Exception
+     */
+    public void testMarshalMap() throws Exception {
+        Map map = new LinkedHashMap();
+        map.put("c", 1);
+        map.put("a", "a-value");
+        Map nestedMap = new LinkedHashMap();
+        nestedMap.put("x", 10);
+        nestedMap.put("y", "y-value");
+        map.put("m", nestedMap);
+        
+        StringWriter w = new StringWriter();
+        XmlMarshaller.marshalDocument(w, "doc", map);
+        
+        String expected = "(?s:)" +
+                "^<\\?xml version=\"1\\.0\" standalone='yes'\\?>\\s*" +
+                "\\s*1\\s*a-value\\s*" +
+                "\\s*10\\s*y-value\\s*\\s*" +
+                "\\s*$";
+        String xml = w.toString();
+        System.out.println(xml);
+        assertTrue("xml matches expected RE", xml.matches(expected));
+    }
+    
+    @XmlRootElement
+    @XmlType(propOrder={"c", "a", "m"})
+    public static class Model {
+        public int getC() { return 1; }
+        public String getA() { return "a-value"; }
+        public Object getM() {
+            return new NestedModel();
+        }
+    }
+    @XmlRootElement
+    @XmlType(propOrder={"x", "y"})
+    public static class NestedModel {
+        public int getX() { return 10; }
+        public String getY() { return "y-value"; }
+    }
+    
+    /**
+     * Bean with nested Bean
+     * @throws Exception
+     */
+    public void testMashalBean() throws Exception {
+        Object bean = new Model();
+        StringWriter w = new StringWriter();
+        XmlMarshaller.marshalDocument(w, "doc", bean);
+        
+        String expected = "(?s:)" +
+                "^<\\?xml version=\"1\\.0\" standalone='yes'\\?>\\s*" +
+                "\\s*1\\s*a-value\\s*" +
+                "\\s*10\\s*y-value\\s*\\s*" +
+                "\\s*$";
+        String xml = w.toString();
+        System.out.println(xml);
+        assertTrue("xml matches expected RE", xml.matches(expected));
+    }
+
+    /**
+     * Map with nested Bean
+     * @throws Exception
+     */
+    public void testMarshalBeanInMap() throws Exception {
+        Map map = new LinkedHashMap();
+        map.put("c", 1);
+        map.put("a", "a-value");
+        Object m = new NestedModel();
+        map.put("m", m);
+        
+        StringWriter w = new StringWriter();
+        XmlMarshaller.marshalDocument(w, "doc", map);
+        
+        String expected = "(?s:)" +
+                "^<\\?xml version=\"1\\.0\" standalone='yes'\\?>\\s*" +
+                "\\s*1\\s*a-value\\s*" +
+                "\\s*10\\s*y-value\\s*\\s*" +
+                "\\s*$";
+        String xml = w.toString();
+        System.out.println(xml);
+        assertTrue("xml matches expected RE", xml.matches(expected));
+    }
+}

From 358afd448673798ea22d99d616b776e8bea2bffa Mon Sep 17 00:00:00 2001
From: Kenji Nagahashi 
Date: Mon, 10 Jun 2013 14:17:27 -0700
Subject: [PATCH 3/3] revised scripting console xml response fix based on
 comments. removed scripting console actions from ScriptModel into
 ScriptingConsole class (resurrection of ScriptExec). added basic
 ScriptingConsoleTest.

---
 .../crawler/restlet/ScriptResource.java       |  20 ++-
 .../crawler/restlet/ScriptingConsole.java     | 129 ++++++++++++++++++
 .../crawler/restlet/models/ScriptModel.java   | 114 ++--------------
 .../crawler/restlet/ScriptingConsoleTest.java |  64 +++++++++
 4 files changed, 215 insertions(+), 112 deletions(-)
 create mode 100644 engine/src/main/java/org/archive/crawler/restlet/ScriptingConsole.java
 create mode 100644 engine/src/test/java/org/archive/crawler/restlet/ScriptingConsoleTest.java

diff --git a/engine/src/main/java/org/archive/crawler/restlet/ScriptResource.java b/engine/src/main/java/org/archive/crawler/restlet/ScriptResource.java
index 5f3da976..dd0fa55c 100644
--- a/engine/src/main/java/org/archive/crawler/restlet/ScriptResource.java
+++ b/engine/src/main/java/org/archive/crawler/restlet/ScriptResource.java
@@ -92,6 +92,8 @@ public class ScriptResource extends JobRelatedResource {
         tmpltCfg.setClassForTemplateLoading(this.getClass(),"");
         tmpltCfg.setObjectWrapper(ObjectWrapper.BEANS_WRAPPER);
         setTemplateConfiguration(tmpltCfg);
+        
+        scriptingConsole = new ScriptingConsole(cj);
     }
     public void setTemplateConfiguration(Configuration tmpltCfg) {
         _templateConfiguration=tmpltCfg;
@@ -100,7 +102,7 @@ public class ScriptResource extends JobRelatedResource {
         return _templateConfiguration;
     }
         
-    private ScriptModel scriptModel;
+    private ScriptingConsole scriptingConsole;
     
     @Override
     public void acceptRepresentation(Representation entity) throws ResourceException {
@@ -113,10 +115,9 @@ public class ScriptResource extends JobRelatedResource {
 
         ScriptEngine eng = MANAGER.getEngineByName(chosenEngine);
         
-        scriptModel = makeDataModel();
-        scriptModel.bind("scriptResource", this);
-        scriptModel.execute(eng, script);
-        scriptModel.unbind("scriptResource");
+        scriptingConsole.bind("scriptResource",  this);
+        scriptingConsole.execute(eng, script);
+        scriptingConsole.unbind("scriptResource");
         
         //TODO: log script, results somewhere; job log INFO? 
         
@@ -124,14 +125,11 @@ public class ScriptResource extends JobRelatedResource {
     }
     
     public Representation represent(Variant variant) throws ResourceException {
-        if (scriptModel == null) {
-            scriptModel = makeDataModel();
-        }
         Representation representation;
         if (variant.getMediaType() == MediaType.APPLICATION_XML) {
             representation = new WriterRepresentation(MediaType.APPLICATION_XML) {
                 public void write(Writer writer) throws IOException {
-                    XmlMarshaller.marshalDocument(writer,"script", scriptModel);
+                    XmlMarshaller.marshalDocument(writer,"script", makeDataModel());
                 }
             };
         } else {
@@ -172,7 +170,7 @@ public class ScriptResource extends JobRelatedResource {
         }
         Reference baseRefRef = new Reference(baseRef);
         
-        ScriptModel model = new ScriptModel(cj,
+        ScriptModel model = new ScriptModel(scriptingConsole,
                 new Reference(baseRefRef, "..").getTargetRef().toString(),
                 getAvailableScriptEngines());
 
@@ -193,7 +191,7 @@ public class ScriptResource extends JobRelatedResource {
         viewModel.put("cssRef", getStylesheetRef());
         viewModel.put("staticRef", getStaticRef(""));
         viewModel.put("baseResourceRef",getRequest().getRootRef().toString()+"/engine/static/");
-        viewModel.put("model", scriptModel);
+        viewModel.put("model", makeDataModel());
         viewModel.put("selectedEngine", chosenEngine);
 
         try {
diff --git a/engine/src/main/java/org/archive/crawler/restlet/ScriptingConsole.java b/engine/src/main/java/org/archive/crawler/restlet/ScriptingConsole.java
new file mode 100644
index 00000000..e18629b9
--- /dev/null
+++ b/engine/src/main/java/org/archive/crawler/restlet/ScriptingConsole.java
@@ -0,0 +1,129 @@
+/**
+ * 
+ */
+package org.archive.crawler.restlet;
+
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.util.LinkedHashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+import javax.script.Bindings;
+import javax.script.ScriptEngine;
+import javax.script.ScriptException;
+
+import org.archive.crawler.framework.BeanLookupBindings;
+import org.archive.crawler.framework.CrawlJob;
+
+/**
+ * ScriptingConsole implements view-independent logic of scripting console.
+ * 
+ * Currently it is short-lived; it is created by ScriptResource for each request and
+ * destroyed after rendering the view.
+ * 
+ * @contributor kenji
+ *
+ */
+public class ScriptingConsole {
+    private final CrawlJob cj;
+
+    private ScriptEngine eng;
+    private String script;
+    private Bindings bindings;
+    
+    private StringWriter rawString;
+    private StringWriter htmlString;
+    private Throwable exception;
+    private int linesExecuted;
+
+    private List> availableGlobalVariables;
+    
+    public ScriptingConsole(CrawlJob job) {
+        this.cj = job;
+        this.bindings = new BeanLookupBindings(this.cj.getJobContext());
+        this.script = "";
+        
+        setupAvailableGlobalVariables();
+    }
+    protected void addGlobalVariable(String name, String desc) {
+        Map var = new LinkedHashMap();
+        var.put("variable", name);
+        var.put("description", desc);
+        availableGlobalVariables.add(var);
+    }
+    private void setupAvailableGlobalVariables() {     
+        availableGlobalVariables = new LinkedList>();
+        addGlobalVariable("rawOut", "a PrintWriter for arbitrary text output to this page");
+        addGlobalVariable("htmlOut", "a PrintWriter for HTML output to this page");
+        addGlobalVariable("job", "the current CrawlJob instance");
+        addGlobalVariable("appCtx", "current job ApplicationContext, if any");
+        // TODO: a bit awkward to have this here, because ScriptingConsole has no ref to
+        // ScriptResource. better to have ScriptResource call #addGlobalVariable(String, String)?
+        addGlobalVariable("scriptResource",
+                "the ScriptResource implementing this page, which offers utility methods");
+    }
+    
+    public void bind(String name, Object obj) {
+        bindings.put(name, obj);
+    }
+    public Object unbind(String name) {
+        return bindings.remove(name);
+    }
+    public void execute(ScriptEngine eng, String script) {
+        // TODO: update through setter rather than passing as method arguments?
+        this.eng = eng;
+        this.script = script;
+        
+        bind("job", cj);
+        rawString = new StringWriter();
+        htmlString = new StringWriter();
+        PrintWriter rawOut = new PrintWriter(rawString);
+        PrintWriter htmlOut = new PrintWriter(htmlString);
+        bind("rawOut", rawOut);
+        bind("htmlOut", htmlOut);
+        bind("appCtx", cj.getJobContext());
+        exception = null;
+        try {
+            this.eng.eval(this.script, bindings);
+            // TODO: should count with RE rather than creating String[]?
+            linesExecuted = script.split("\r?\n").length;
+        } catch (ScriptException ex) {
+            Throwable cause = ex.getCause();
+            exception = cause != null ? cause : ex;
+        } catch (RuntimeException ex) {
+            exception = ex;
+        } finally {
+            rawOut.flush();
+            htmlOut.flush();
+            // TODO: are these really necessary? 
+            unbind("rawOut");
+            unbind("htmlOut");
+            unbind("appCtx");
+            unbind("job");
+        }
+    }
+    public CrawlJob getCrawlJob( ) {
+        return cj;
+    }
+    public Throwable getException() {
+        return exception;
+    }
+    public int getLinesExecuted() {
+        return linesExecuted;
+    }
+    public String getRawOutput() {
+        return rawString != null ? rawString.toString() : "";
+    }
+    public String getHtmlOutput() {
+        return htmlString != null ? htmlString.toString() : "";
+    }
+    public String getScript() {
+        return script;
+    }
+    
+    public List> getAvailableGlobalVariables() {
+        return availableGlobalVariables;
+    }
+}
diff --git a/engine/src/main/java/org/archive/crawler/restlet/models/ScriptModel.java b/engine/src/main/java/org/archive/crawler/restlet/models/ScriptModel.java
index e748ed76..0fa5a970 100644
--- a/engine/src/main/java/org/archive/crawler/restlet/models/ScriptModel.java
+++ b/engine/src/main/java/org/archive/crawler/restlet/models/ScriptModel.java
@@ -3,19 +3,13 @@ package org.archive.crawler.restlet.models;
 import java.io.PrintWriter;
 import java.io.StringWriter;
 import java.util.Collection;
-import java.util.LinkedHashMap;
-import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 
-import javax.script.Bindings;
-import javax.script.ScriptEngine;
-import javax.script.ScriptException;
 import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.bind.annotation.XmlType;
 
-import org.archive.crawler.framework.BeanLookupBindings;
-import org.archive.crawler.framework.CrawlJob;
+import org.archive.crawler.restlet.ScriptingConsole;
 
 @XmlRootElement(name="script")
 @XmlType(propOrder={
@@ -24,134 +18,52 @@ import org.archive.crawler.framework.CrawlJob;
         "availableGlobalVariables"
 })
 public class ScriptModel {
-    private CrawlJob cj;
     private String crawlJobUrl;
     private Collection> availableScriptEngines;
-    
-    //private ApplicationContext appCtx;
-    private ScriptEngine eng;
-    private String script;
-    private Bindings bindings;
-    
-    private StringWriter rawString;
-    private StringWriter htmlString;
-    private Throwable exception;
-    private int linesExecuted;
-    
-    private List> availableGlobalVariables;
+    private ScriptingConsole scriptingConsole;
 
-	public ScriptModel(CrawlJob cj,
+	public ScriptModel(ScriptingConsole cc,
 	        String crawlJobUrl,
 			Collection> scriptEngines) {
+	    scriptingConsole = cc;
 	    this.crawlJobUrl = crawlJobUrl;
-	    this.cj = cj;
 	    this.availableScriptEngines = scriptEngines;
-        
-        List> vars = new LinkedList>();
-        Map var;
-        
-        var = new LinkedHashMap();
-        var.put("variable", "rawOut");
-        var.put("description", "a PrintWriter for arbitrary text output to this page");
-        vars.add(var);
-        
-        var = new LinkedHashMap();
-        var.put("variable", "htmlOut");
-        var.put("description", "a PrintWriter for HTML output to this page");
-        vars.add(var);
-        
-        var = new LinkedHashMap();
-        var.put("variable", "job");
-        var.put("description", "the current CrawlJob instance");
-        vars.add(var);
-        
-        var = new LinkedHashMap();
-        var.put("variable", "appCtx");
-        var.put("description", "current job ApplicationContext, if any");
-        vars.add(var);
-        
-        var = new LinkedHashMap();
-        var.put("variable", "scriptResource");
-        var.put("description", "the ScriptResource implementing this page, which offers utility methods");
-        vars.add(var);
-        
-        this.availableGlobalVariables = vars;
-        
-        this.bindings = new BeanLookupBindings(this.cj.getJobContext());
-        this.script = "";
     }
 	
-    public void bind(String name, Object obj) {
-        bindings.put(name, obj);
-    }
-    public Object unbind(String name) {
-        return bindings.remove(name);
-    }
-    public void execute(ScriptEngine eng, String script) {
-        // TODO: update through setter rather than passing as method arguments?
-        this.eng = eng;
-        this.script = script;
-        
-        bind("job", cj);
-        rawString = new StringWriter();
-        htmlString = new StringWriter();
-        PrintWriter rawOut = new PrintWriter(rawString);
-        PrintWriter htmlOut = new PrintWriter(htmlString);
-        bind("rawOut", rawOut);
-        bind("htmlOut", htmlOut);
-        bind("appCtx", cj.getJobContext());
-        try {
-            this.eng.eval(this.script, bindings);
-            // TODO: should count with RE rather than creating String[]?
-            linesExecuted = script.split("\r?\n").length;
-        } catch (ScriptException ex) {
-            Throwable cause = ex.getCause();
-            exception = cause != null ? cause : ex;
-        } catch (RuntimeException ex) {
-            exception = ex;
-        } finally {
-            rawOut.flush();
-            htmlOut.flush();
-            // TODO: are these really necessary? 
-            unbind("rawOut");
-            unbind("htmlOut");
-            unbind("appCtx");
-            unbind("job");
-        }
-    }
     public boolean isFailure() {
-        return exception != null;
+        return scriptingConsole.getException() != null;
     }
     public String getStackTrace() {
+        Throwable exception = scriptingConsole.getException();
         if (exception == null) return "";
         StringWriter s = new StringWriter();
         exception.printStackTrace(new PrintWriter(s));
         return s.toString();
     }
     public Throwable getException() {
-        return exception;
+        return scriptingConsole.getException();
     }
     public int getLinesExecuted() {
-        return linesExecuted;
+        return scriptingConsole.getLinesExecuted();
     }
     public String getRawOutput() {
-        return rawString != null ? rawString.toString() : "";
+        return scriptingConsole.getRawOutput();
     }
     public String getHtmlOutput() {
-        return htmlString != null ? htmlString.toString() : "";
+        return scriptingConsole.getHtmlOutput();
     }
     public String getScript() {
-        return script;
+        return scriptingConsole.getScript();
     }
     
     public String getCrawlJobShortName() {
-        return cj.getShortName();
+        return scriptingConsole.getCrawlJob().getShortName();
     }
     public Collection> getAvailableScriptEngines() {
         return availableScriptEngines;
     }
     public List> getAvailableGlobalVariables() {
-        return availableGlobalVariables;
+        return scriptingConsole.getAvailableGlobalVariables();
     }
     public String getCrawlJobUrl() {
         return crawlJobUrl;
diff --git a/engine/src/test/java/org/archive/crawler/restlet/ScriptingConsoleTest.java b/engine/src/test/java/org/archive/crawler/restlet/ScriptingConsoleTest.java
new file mode 100644
index 00000000..34c096b3
--- /dev/null
+++ b/engine/src/test/java/org/archive/crawler/restlet/ScriptingConsoleTest.java
@@ -0,0 +1,64 @@
+package org.archive.crawler.restlet;
+
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineManager;
+
+import junit.framework.TestCase;
+
+import org.archive.crawler.framework.CrawlJob;
+import org.archive.spring.PathSharingContext;
+
+public class ScriptingConsoleTest extends TestCase {
+    // barebone CrawlJob object.
+    public static class TestCrawlJob extends CrawlJob {
+        public TestCrawlJob() {
+            super(null);
+            this.ac = new PathSharingContext(new String[0]);
+        }
+        @Override
+        protected void scanJobLog() {
+        }
+    }
+    CrawlJob cj;
+    ScriptingConsole sc;
+    
+    protected void setUp() throws Exception {
+        super.setUp();
+        cj = new TestCrawlJob();
+        sc = new ScriptingConsole(cj);
+    }
+
+    public void testInitialState() {
+        assertEquals("script is empty", "", sc.getScript());
+        assertNull("exception is null", sc.getException());
+    }
+    
+    public void testExecute() {
+        final String script = "rawOut.println 'elk'";
+        final ScriptEngineManager manager = new ScriptEngineManager();
+        final ScriptEngine eng = manager.getEngineByName("groovy");
+        sc.execute(eng, script);
+        
+        assertNull("exception is null", sc.getException());
+        assertEquals("has the same script", sc.getScript(), script);
+        assertEquals("linesExecuted", 1, sc.getLinesExecuted());
+        assertEquals("rawOut", "elk\n", sc.getRawOutput());
+        
+    }
+    
+    public void testExecuteError() {
+        final String script = "rawOut.println undef";
+        final ScriptEngineManager manager = new ScriptEngineManager();
+        final ScriptEngine eng = manager.getEngineByName("groovy");
+        sc.execute(eng, script);
+        
+        assertNotNull("exception is non-null", sc.getException());
+        assertEquals("rawOut", "", sc.getRawOutput());
+        assertEquals("linesExecuted", 0, sc.getLinesExecuted());
+        
+        // extra test - it is okay to fail this test is okay because
+        // ScriptingConsole is single-use now.
+        sc.execute(eng, "rawOut.println 1");
+        assertNull("exception is cleared", sc.getException());
+    }
+}