3 import org.ibex.util.*;
8 import javax.servlet.*;
9 import javax.servlet.http.*;
10 import com.thoughtworks.xstream.*;
11 import org.prevayler.*;
12 import org.prevayler.implementation.snapshot.*;
15 public class Servlet extends HttpServlet {
17 private ServletResolver resolver = new ServletResolver();
18 private class ServletResolver implements XML.Node.Stream.Resolver {
19 public XML.Node.Stream.Functor resolve(String uri) {
20 if (uri.indexOf(':') == -1) throw new RuntimeException("uri does not contain an method: " + uri);
21 String method = uri.substring(0, uri.indexOf(':'));
22 String rest = uri.substring(uri.indexOf(':'))+1;
23 //case "xtree": return XTree.tag(rest);
25 case "webinf": return new Template(cx.getRealPath(rest));
26 case "java": try { return (XML.Node.Stream.Functor)Class.forName(rest).newInstance(); }
27 catch (Exception e) { throw new RuntimeException(e); }
29 throw new RuntimeException("unknown method " + method);
33 public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
34 JSScope scope = new ServletScope(request, response);
35 String path = cx.getRealPath(((HttpServletRequest)request).getServletPath());
36 Reader xmlreader = new InputStreamReader(new FileInputStream(path));
37 XML.Node.Stream s = new JSRewriter(XML.Node.Stream.in(xmlreader), scope);
38 s.out(response.getWriter());
41 public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException { doGet(request, response); }
43 public class ServletScope extends JSScope {
44 HttpServletRequest request;
45 HttpServletResponse response;
46 public ServletScope(ServletRequest request, ServletResponse response) {
48 this.request = (HttpServletRequest)request;
49 this.response = (HttpServletResponse)response;
51 private JS params = new JS() {
52 public Object get(Object key) { return request.getParameter(JS.toString(key)); }
53 public Enumeration keys() { return request.getParameterNames(); }
55 private JS cookies = new JS() {
57 public Object get(Object key) { return request.getCookie(JS.toString(key)); }
58 public Enumeration keys() { return request.getCookieNames(); }
61 private JS sessionAttributes = new JS() {
62 public Object get(Object key) { return request.getSession(true).getAttribute(JS.toString(key)); }
63 public void put(Object key, Object val) {
64 if (val == null) request.getSession(true).removeAttribute(JS.toString(key));
65 else request.setAttribute(JS.toString(key), val); }
66 public Enumeration keys() { return request.getSession(true).getAttributeNames(); }
68 private JS requestHeader = new JS() {
69 public Object get(Object key) { return request.getHeader(JS.toString(key)); }
70 public Enumeration keys() { return request.getHeaderNames(); }
72 private JS responseHeader = new JS() {
73 public void put(Object key, Object val) { response.setHeader(JS.toString(key), JS.toString(val)); }
77 /** lets us put multi-level get/put/call keys all in the same method */
78 private class Sub extends JS {
80 Sub(Object key) { this.key = key; }
81 public void put(Object key, Object val) throws JSExn {
82 ServletScope.this.put(JS.toString(this.key) + "." + JS.toString(key), val); }
83 public Object get(Object key) throws JSExn {
84 return ServletScope.this.get(JS.toString(this.key) + "." + JS.toString(key)); }
85 public Object call(Object a0, Object a1, Object a2, Object[] rest, int nargs) throws JSExn {
86 return ServletScope.this.callMethod(this.key, a0, a1, a2, rest, nargs);
88 public Object callMethod(Object method, Object a0, Object a1, Object a2, Object[] rest, int nargs) throws JSExn {
89 return ServletScope.this.callMethod(JS.toString(this.key) + "."
90 + JS.toString(method), a0, a1, a2, rest, nargs);
93 private Sub getSub(String key) { return new Sub(key); }
95 public Object callMethod(Object method, final Object a, final Object b, Object c, Object[] rest, int nargs) throws JSExn {
97 case "prevalent.query":
99 return prevayler.execute(new JSQuery(JS.cloneWithNewParentScope((JS)a, null)));
100 } catch (Exception e) {
102 throw new RuntimeException(e); }
104 case "prevalent.execute":
106 prevayler.execute(new JSTransaction(JS.cloneWithNewParentScope((JS)a, null)));
107 } catch (Exception e) {
109 throw new RuntimeException(e); }
111 case "session.invalidate": request.getSession(true).invalidate(); return null;
115 public Object get(Object key) throws JSExn {
118 case "arg": return null;
119 case "prevalent": return getSub("prevalent");
120 case "prevalent.query": return METHOD;
121 case "prevalent.execute": return METHOD;
122 case "request": return getSub("request");
123 case "request.user": return request.getRemoteUser();
124 case "request.header": return requestHeader;
125 case "request.method": return request.getMethod();
126 case "request.remote": return getSub("request.remote");
127 case "request.remote.ip": return request.getRemoteAddr();
128 case "request.remote.host": return request.getRemoteHost();
129 case "request.ssl": return request.isSecure();
130 case "request.path": return request.getPathInfo();
131 case "response": return getSub("response");
132 case "response.header": return responseHeader;
133 case "session": return getSub("session");
134 case "session.attr": return sessionAttributes;
135 case "session.created": return new JSDate(request.getSession(true).getCreationTime());
136 case "session.accessed": return new JSDate(request.getSession(true).getLastAccessedTime());
137 case "session.invalidate": return METHOD;
138 case "params": return params;
139 case "cookie": return cookies;
143 public void put(Object key, Object val) throws JSExn {
145 //#switch(JS.toString(key))
146 case "response.code": response.setStatus(JS.toInt(val));
147 case "response.redirect": response.sendRedirect(JS.toString(val));
148 case "response.contentType": response.setContentType(JS.toString(val));
150 } catch (IOException e) {
156 // Prevalence //////////////////////////////////////////////////////////////////////////////
158 static final Hashtable prevaylers = new Hashtable();
159 private Prevayler prevayler;
160 private JS prevalent;
161 private ServletContext cx = null;
162 public void destroy() {
164 synchronized(this.getClass()) {
165 Prevayler privatePrevayler = prevayler;
166 if (prevayler == null) return;
168 prevaylers.remove(cx);
169 prevayler.takeSnapshot();
172 } catch (Exception e) {
177 private static class SnapshotThread extends Thread {
179 public SnapshotThread(ServletContext cx) { this.cx = cx; }
183 Prevayler privatePrevayler = (Prevayler)prevaylers.get(cx);
184 if (privatePrevayler == null) return;
185 privatePrevayler.takeSnapshot();
186 } catch (Exception e) {
192 public void init(ServletConfig sc) throws ServletException {
194 cx = sc.getServletContext();
196 prevayler = (Prevayler)prevaylers.get(cx);
197 if (prevalent == null) {
198 PrevaylerFactory pf = new PrevaylerFactory();
199 String base = cx.getRealPath("/") + "WEB-INF" + File.separatorChar + "prevalent";
200 System.err.println("prevayling to " + base);
201 pf.configurePrevalenceBase(base);
202 XStreamSnapshotManager manager = new XStreamSnapshotManager(new JS(), base, null) {
203 protected XStream createXStream() {
204 XStream xstream = new XStream();
205 xstream.alias("js", JS.class);
206 xstream.alias("jsdate", JSDate.class);
210 System.err.println("configuring with " + manager);
211 pf.configureSnapshotManager(manager);
212 //pf.configureClassLoader(JSTransaction.class.getClassLoader());
213 prevayler = pf.create();
214 prevaylers.put(cx, prevayler);
215 new SnapshotThread(cx).start();
218 prevalent = (JS)prevayler.prevalentSystem();
219 } catch (Exception e) {
220 throw new ServletException(e);
224 public static class JSTransaction implements Transaction {
226 public JSTransaction(JS js) { this.js = js; }
227 public void executeOn(Object o, Date now) {
229 js.call(o, new JSDate(now.getTime()), null, null, 2);
230 } catch (Exception e) { throw new RuntimeException(e); }
234 public static class JSQuery implements Query {
236 public JSQuery(JS js) { this.js = js; }
237 public Object query(Object o, Date now) {
239 return js.call(o, new JSDate(now.getTime()), null, null, 2);
240 } catch (Exception e) { throw new RuntimeException(e); }