/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/PluginEnvironment.java |
---|
0,0 → 1,200 |
package net.outlyer.plugins.sandboxing; |
import net.outlyer.plugins.PluginException; |
import java.io.IOException; |
import java.io.LineNumberReader; |
import java.lang.reflect.Field; |
import java.net.URI; |
import java.util.Arrays; |
import java.util.HashMap; |
import java.util.List; |
import java.util.Map; |
import javax.script.Bindings; |
import javax.script.ScriptEngine; |
import javax.script.ScriptEngineManager; |
import javax.script.ScriptException; |
import net.outlyer.plugins.API; |
import net.outlyer.plugins.BasePluginObject; |
import net.outlyer.plugins.PluginObject; |
import net.outlyer.plugins.PluginProperties; |
/** |
* Provides the environment for {@link net.outlyer.plugins.sandboxing.Sandbox}es. |
*/ |
public class PluginEnvironment { |
static class UnsupportedAPIException extends PluginException { |
public UnsupportedAPIException(int providedApi) { |
super("Plugin has unsupported API ("+providedApi+")"); |
} |
} |
static class UnsupportedTypeException extends PluginException { |
public UnsupportedTypeException(String pluginType) { |
super("Plugin has unsupported type ("+pluginType+")"); |
} |
} |
private final Map<String, Object> exportedObjects; |
private BasePluginObject pluginObject; |
private StringBuilder boilerPlate; |
private List<String> acceptedTypes = null; |
private int maxApi=API.REVISION; |
int linesToCheckForSupport = 5; |
static final String EXPORTED_SANDBOX_VARIABLE = "$net.outlyer.runtime.sandbox"; |
{ |
exportedObjects = new HashMap(); |
pluginObject = null; |
boilerPlate = new StringBuilder(); |
} |
private void enableSandboxAccess(final String name, final SandboxAccessor sa) { |
try { |
Field f = sa.getClass().getField("_getSandbox"); |
} |
catch (final NoSuchFieldException e) { |
throw new IllegalArgumentException("object " + name + " must comply " + |
"with the contract of SandboxAccessor"); |
} |
final String callback = name + "._getSandbox"; |
boilerPlate.append(callback).append("=function() {") |
.append(" return ") |
.append(EXPORTED_SANDBOX_VARIABLE).append(";\n};"); |
} |
public void exportGlobalObject(String name, Object object) { |
exportedObjects.put(name, object); |
if (object instanceof SandboxAccessor) { |
enableSandboxAccess(name, (SandboxAccessor)object); |
} |
} |
public void setPluginObject(BasePluginObject pObject) { |
pluginObject = pObject; |
} |
public PluginProperties checkForSupport(final URI uri) throws PluginException { |
final ScriptEngine rhino = new ScriptEngineManager().getEngineByName("rhino"); |
try { |
// Define a Plugin object with a field named type |
rhino.eval("var plugin={ type: null, apiVersion: null };"); |
} |
catch (ScriptException e) { |
assert false; |
throw new IllegalStateException("Unknown error encountered"); |
} |
// First of all check the script for support |
Object type = null; |
Object apiVersion = null; |
// Try to eval each line, since it executes in a sandbox this is |
// *relatively* safe |
String line; |
try { |
final LineNumberReader script = new LineNumberReader(new PluginReader(uri)); |
try { |
while ((null == type || null == apiVersion) && |
(null != (line = script.readLine())) && |
script.getLineNumber() < linesToCheckForSupport) { |
try { |
rhino.eval(line); |
if (null == type) { |
rhino.eval("$_1_$ = plugin.type;"); |
type = rhino.get("$_1_$"); |
} |
if (null == apiVersion) { |
rhino.eval("$_1_$ = plugin.apiVersion;"); |
apiVersion = rhino.get("$_1_$"); |
} |
} |
catch (ScriptException e) { |
// Exceptions are to be expected since none of the guaranteed |
// plugin tools are provided in this context they'll try to |
// access unexisting objects |
} |
} |
} |
finally { |
script.close(); |
} |
} |
catch (final IOException e) { |
throw new PluginExecutionException("Failed while reading plugin: " + e.getMessage(), e); |
} |
if (null == type) { |
type = ""; |
} |
if (null == apiVersion) { |
apiVersion = 0; |
} |
final PluginProperties pp = new PluginProperties(); |
try { |
pp.apiVersion = Double.valueOf(apiVersion.toString()).intValue(); |
pp.type = type.toString(); |
} |
catch (final NumberFormatException e) { |
throw new PluginException("Incorrect value for apiVersion provided, must be integer"); |
} |
if (null != acceptedTypes) { |
if (!acceptedTypes.contains(pp.type)) { |
throw new UnsupportedTypeException(pp.type); |
} |
} |
if (pp.apiVersion > maxApi) { |
throw new UnsupportedAPIException(pp.apiVersion); |
} |
return pp; |
} |
public Sandbox createSandbox(final URI forUri) throws PluginException { |
final ScriptEngine rhino = new ScriptEngineManager().getEngineByName("rhino"); |
final PluginProperties pp = checkForSupport(forUri); |
if (null == pluginObject) { |
pluginObject = new PluginObject(); |
} |
try { |
final PluginObject po = (PluginObject) pluginObject.clone(); |
final Bindings bindings = rhino.createBindings(); |
for (final String objectName : exportedObjects.keySet()) { |
bindings.put(objectName, exportedObjects.get(objectName)); |
} |
bindings.put("plugin", po); |
enableSandboxAccess("plugin", po); |
return new SandboxImpl(forUri, bindings, boilerPlate.toString()); |
} |
catch (final CloneNotSupportedException e) { |
assert false; |
throw new IllegalStateException("Incorrect implementation"); |
} |
} |
public void setAcceptedTypes(final String ... pluginTypes) { |
if (null != pluginTypes) { |
for (final String type : pluginTypes) { |
if (null == type) { |
throw new IllegalArgumentException("The set of plugin types" + |
" must be either null, or a set of non-null values"); |
} |
} |
} |
acceptedTypes = Arrays.asList(pluginTypes); |
} |
} |
/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/SandboxAccessorImpl.java |
---|
0,0 → 1,23 |
package net.outlyer.plugins.sandboxing; |
import java.util.concurrent.Callable; |
/** |
* {@see SandboxAccessor} |
*/ |
public abstract class SandboxAccessorImpl implements SandboxAccessor { |
public Callable<Sandbox> _getSandbox; |
protected final Sandbox getSandbox() { |
if (null == _getSandbox) { |
throw new IllegalStateException(getClass()+" hasn't been correctly initialised"); |
} |
try { |
return _getSandbox.call(); |
} |
catch (final Exception e) { |
throw new IllegalStateException("getSandbox produced an exception, which is not expected!"); |
} |
} |
} |
/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/RuntimeHooks.java |
---|
0,0 → 1,11 |
package net.outlyer.plugins.sandboxing; |
/** |
* Provides hooks to the execution |
*/ |
public interface RuntimeHooks { |
/** |
* Adds a callback to be executed after the script is finished |
*/ |
void addEndHook(final Runnable r); |
} |
/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/SandboxProperties.java |
---|
0,0 → 1,9 |
package net.outlyer.plugins.sandboxing; |
/** |
* Provides access to some properties of a sandbox |
* @see Sandbox |
*/ |
public interface SandboxProperties { |
public int getExecution(); |
} |
/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/Sandbox.java |
---|
0,0 → 1,46 |
package net.outlyer.plugins.sandboxing; |
import net.outlyer.plugins.BasePluginObject; |
/** |
* Public methods provided by the sandbox. |
* Note that all methods in this interface imply a call to {@link #execute}. |
*/ |
public interface Sandbox extends RuntimeHooks, SandboxProperties { |
/** |
* @see #createDelayedImplementation(Class, boolean) |
*/ |
<T> T createDelayedImplementation(final Class<T> interfaceClass) throws PluginExecutionException; |
/** |
* Creates an implementation of an interface from JS code |
* @param interfaceClass Class of the interface to implement |
* @param allowPartialImplementation If true, the implementation would be used |
* even if incomplete (note that calling an unimplemented method will produce |
* an exception) |
* @return The implementation |
* @throws net.outlyer.plugins.sandboxing.PluginExecutionException |
*/ |
<T> T createDelayedImplementation(final Class<T> interfaceClass, boolean allowPartialImplementation) throws PluginExecutionException; |
/** |
* @see #createDelayedImplementation(Class, boolean) |
* @param fallbackObject If not null incomplete implementations are allowed and |
* calls to undefined methods will be passed to this object |
*/ |
<T> T createDelayedImplementation(final Class<T> interfaceClass, final T fallbackObject) throws PluginExecutionException; |
<T> T createDelayedImplementation(final Class<T> interfaceClass, final String objectName) throws PluginExecutionException; |
/** |
* Run the script |
*/ |
void execute() throws PluginExecutionException; |
/** |
* Obtains object contauning the plugin object |
* @return |
*/ |
BasePluginObject getPluginObject() throws PluginExecutionException; |
} |
/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/SandboxImpl.java |
---|
0,0 → 1,253 |
package net.outlyer.plugins.sandboxing; |
import java.io.IOException; |
import java.lang.reflect.Method; |
import java.net.URI; |
import java.util.Collection; |
import java.util.HashMap; |
import java.util.LinkedList; |
import java.util.Map; |
import javax.script.Bindings; |
import javax.script.ScriptContext; |
import javax.script.ScriptEngine; |
import javax.script.ScriptEngineManager; |
import javax.script.ScriptException; |
import net.outlyer.plugins.BasePluginObject; |
/** |
* Implementation of the Sandbox interface |
*/ |
class SandboxImpl implements Sandbox { |
private final Bindings bindings; |
private final URI pluginUri; |
private static int nextUniqueVarNum; |
private Map<String, Collection<Runnable>> hooks; |
private final String boilerPlate; |
private int execution = 0; |
private static final String END_KEY = "e"; |
static { |
nextUniqueVarNum = (int) (1193 * (1+Math.random())); |
} |
{ |
hooks = new HashMap<String, Collection<Runnable>>(); |
hooks.put(END_KEY, new LinkedList<Runnable>()); |
} |
protected SandboxImpl(final URI plugin, final Bindings bs) { |
this(plugin, bs, null); |
} |
protected SandboxImpl(final URI plugin, final Bindings bs, final String boilerPlate) { |
bindings = bs; |
pluginUri = plugin; |
this.boilerPlate = boilerPlate; |
} |
public void addEndHook(Runnable r) { |
hooks.get(END_KEY).add(r); |
} |
/** |
* Namespace for variables used by the enviroment |
*/ |
private static String namespace() { |
return "$net.outlyer.runtime"; |
} |
/** |
* Creates a unique variable name. |
*/ |
private static String uniqueVarName() { |
return new StringBuilder("$_").append(nextUniqueVarNum+=1193).append("_$").toString(); |
} |
/** |
* Creates a unique variable name including namespace |
* @see #namespace |
* @see #uniqueVarName |
*/ |
private static String uniqueFQVarName() { |
return new StringBuilder(namespace()).append(".") |
.append(uniqueVarName()).toString(); |
} |
private static ScriptEngine getEngine() { |
return new ScriptEngineManager().getEngineByName("rhino"); |
} |
private ScriptEngine execute(boolean appendText, String text, final Map<String,Object> extraBindings) |
throws PluginExecutionException { |
final ScriptEngine rhino = getEngine(); |
// First, export in the global namespace the reference to this |
// sandbox. This variable isn't meant to be used directly, it's only |
// set to refer to it from the boilerplate code (AFAIK there's no |
// way to add a binding with a FQ name). |
// TODO: Can a fully qualified name be bound directly? |
final String globalSanboxVarName = uniqueVarName(); |
bindings.put(globalSanboxVarName, this); |
if (null != extraBindings) { |
for (final String key : extraBindings.keySet()) { |
bindings.put(key, extraBindings.get(key)); |
} |
} |
// Will contain some biolerplate code used to provide access |
// to the runtime wrapped-environment |
final StringBuilder runtime = new StringBuilder(); |
// $net.outlyer.runtime.sandbox Contains a reference to this object |
// Implementation note: PluginEnvironment.EXPORTED_SANDBOX_VARIABLE should have the same name |
// TODO: ? $net.outlyer.runtime.pluginEnvironment |
runtime.append("var $net = {\n") |
.append(" outlyer : {\n") |
.append(" runtime : {\n") |
.append(" sandbox : ").append(globalSanboxVarName).append("\n") |
.append(" }\n") |
.append(" }\n") |
.append("};\n"); |
try { |
rhino.setBindings(bindings, ScriptContext.ENGINE_SCOPE); |
execution++; |
if (null != boilerPlate) { |
rhino.eval(boilerPlate); |
} |
// Create the $net.outlyer.runtime pseudo-namespace... |
rhino.eval(runtime.toString()); |
rhino.eval(new PluginReader(pluginUri)); |
if (appendText) { |
rhino.eval(text); |
} |
// Execute any end hooks |
for (final Runnable hook : hooks.get(END_KEY)) { |
hook.run(); |
} |
} |
catch (final IOException e) { |
throw new PluginExecutionException("I/O Error: " + e.getMessage(), e); |
} |
catch (final ScriptException e) { |
throw new PluginExecutionException("Script exception: " + e.getMessage(), e); |
} |
return rhino; |
} |
public void execute() throws PluginExecutionException { |
execute(false, null, null); |
} |
public <T> T createDelayedImplementation(Class<T> c, String objectName) |
throws PluginExecutionException { |
final String varImpl = uniqueVarName(); |
final StringBuilder code = new StringBuilder(); |
code.append(varImpl).append(" = new ") |
.append(c.getCanonicalName()).append("(").append(objectName).append(");"); |
//System.err.println(code.toString()); |
final ScriptEngine rhino = execute(true, code.toString(), null); |
assert (c.isInstance(rhino.get(varImpl))); |
return (T) rhino.get(varImpl); |
} |
public <T> T createDelayedImplementation(Class<T> c) throws PluginExecutionException { |
return createDelayedImplementation(c, false); |
} |
public <T> T createDelayedImplementation(Class<T> c, boolean allowPartial) throws PluginExecutionException { |
return createDelayedImplementation(c, null, allowPartial); |
} |
public <T> T createDelayedImplementation(Class<T> interfaceClass, final T fallbackObject) throws PluginExecutionException { |
if (null == fallbackObject) { |
throw new IllegalArgumentException("Can't use a null fallback object"); |
} |
return createDelayedImplementation(interfaceClass, fallbackObject, true); |
} |
private <T> T createDelayedImplementation(Class<T> c, T fallback, boolean allowPartial) throws PluginExecutionException { |
final StringBuilder hack = new StringBuilder(); |
final String var = uniqueFQVarName(); |
// Apparently only global namespace objects can be retrieved with get() |
// so to simplify retrieval a global variable is used |
final String varImpl = uniqueVarName(); |
hack.append(var).append("={\n"); |
final StringBuilder script = new StringBuilder(); |
final String varFallback = uniqueVarName(); |
for (final Method m : c.getMethods()) { |
if (m.getDeclaringClass() != c) { |
continue; |
} |
final String implFuncName = c.getSimpleName()+"_"+m.getName(); |
if (allowPartial) { |
// This makes undefined functions to be mapped to undefined |
// variables (otherwise the interface instantation would fail) |
// Apparently defining a var with the same name as a function |
// produces no error, while checking for an undefined |
// variable/method does fail. |
script.append("var ").append(implFuncName).append(";\n"); |
if (null != fallback) { |
script.append("if (!").append(implFuncName).append(")\n\t") |
.append(implFuncName).append("=") |
.append(varFallback).append(".").append(m.getName()) |
.append("\n"); |
} |
// script.append("if (!").append(implFuncName).append(") ") |
// .append(implFuncName).append("=null;\n"); |
} |
hack.append("\t").append(m.getName()).append(" : ").append(implFuncName).append(",\n"); |
} |
hack.append("};\nvar ") |
.append(varImpl).append("=new ") |
.append(c.getCanonicalName()).append("(").append(var).append(");"); |
script.append(hack.toString()); |
final HashMap<String, Object> bn = new HashMap(); |
bn.put(varFallback, fallback); |
if (null != fallback) { |
script.append("\n// " + bn.get(varFallback).getClass()); |
} |
//System.err.println(script.toString()); |
final ScriptEngine rhino = execute(true, script.toString(), bn); |
assert (c.isInstance(rhino.get(varImpl))); |
return (T) rhino.get(varImpl); |
} |
public BasePluginObject getPluginObject() throws PluginExecutionException { |
execute(); |
assert bindings.get("plugin") instanceof BasePluginObject; |
return (BasePluginObject) bindings.get("plugin"); |
} |
public int getExecution() { |
return execution; |
} |
} |
/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/PluginExecutionException.java |
---|
0,0 → 1,25 |
package net.outlyer.plugins.sandboxing; |
import net.outlyer.plugins.PluginException; |
/** |
* |
*/ |
public class PluginExecutionException extends PluginException { |
public PluginExecutionException(Throwable cause) { |
super(cause); |
} |
public PluginExecutionException(String message, Throwable cause) { |
super(message, cause); |
} |
public PluginExecutionException(String message) { |
super(message); |
} |
public PluginExecutionException() { |
} |
} |
/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/PluginReader.java |
---|
0,0 → 1,51 |
package net.outlyer.plugins.sandboxing; |
import java.io.File; |
import java.io.FileNotFoundException; |
import java.io.FileReader; |
import java.io.IOException; |
import java.io.InputStream; |
import java.io.InputStreamReader; |
import java.io.Reader; |
import java.net.URI; |
/** |
* java.io.Reader for plugins, tries to abstract the plugin location (file or jar) |
*/ |
class PluginReader extends Reader { |
private final Reader readerImpl; |
PluginReader(final URI uri) throws IOException { |
super(); |
assert null != uri; |
try { |
if (uri.getScheme().equals("file")) { |
readerImpl = new FileReader(new File(uri)); |
} |
else { |
final String path = uri.getSchemeSpecificPart().split("!")[1]; |
final InputStream is = getClass().getResourceAsStream(path); |
if (null == is) { |
throw new IOException("Failed to get resource for " + uri); |
} |
readerImpl = new InputStreamReader(is); |
} |
} |
catch (final FileNotFoundException e) { |
throw new IOException("Can\'t read input " + uri); |
} |
} |
@Override |
public int read(char[] cbuf, int off, int len) throws IOException { |
return readerImpl.read(cbuf, off, len); |
} |
@Override |
public void close() throws IOException { |
readerImpl.close(); |
} |
} |
/pluggablejs/trunk/src/net/outlyer/plugins/sandboxing/SandboxAccessor.java |
---|
0,0 → 1,17 |
package net.outlyer.plugins.sandboxing; |
/** |
* Optional interface for exported objects (see |
* {@link net.outlyer.plugins.sandboxing.PluginEnvironment#exportGlobalObject}), |
* it enables exported objects to retrieve the sandbox object in which they're |
* being executed. |
* |
* Implementors must contain a field exactly: |
* |
* public Callable<Sandbox> _getSandbox = null; |
* |
* The convenience default implementation, {@link SandboxAccessorImpl} can |
* be used as a base class if that's possible, to hide such requirement. |
*/ |
public interface SandboxAccessor { |
} |