java/com/google/gitiles/Renderer.java - gitiles - Git at Google

 // Copyright 2012 Google Inc. 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 com.google.gitiles;

 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
 import static java.nio.charset.StandardCharsets.UTF_8;

 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Maps;
 import com.google.common.hash.Funnels;
 import com.google.common.hash.HashCode;
 import com.google.common.hash.Hasher;
 import com.google.common.hash.Hashing;
 import com.google.common.html.types.LegacyConversions;
 import com.google.common.io.ByteStreams;
 import com.google.common.net.HttpHeaders;
 import com.google.template.soy.jbcsrc.api.SoySauce;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.function.Function;
 import java.util.zip.GZIPOutputStream;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 /**
  * Renderer for Soy templates used by Gitiles.
  *
  * <p>Most callers should not use the methods in this class directly, and instead use one of the
  * HTML methods in {@link BaseServlet}.
  */
 public abstract class Renderer {
   // Must match .streamingPlaceholder.
   private static final String PLACEHOLDER = "id=\"STREAMED-OUTPUT-BLOCK\"";

   private static final ImmutableList<String> SOY_FILENAMES =
       ImmutableList.of(
           "BlameDetail.soy",
           "Common.soy",
           "DiffDetail.soy",
           "Doc.soy",
           "Error.soy",
           "HostIndex.soy",
           "LogDetail.soy",
           "ObjectDetail.soy",
           "PathDetail.soy",
           "RefList.soy",
           "RevisionDetail.soy",
           "RepositoryIndex.soy");

   public static final ImmutableMap<String, String> STATIC_URL_GLOBALS =
       ImmutableMap.of(
           "gitiles.BASE_CSS_URL", "base.css",
           "gitiles.DOC_CSS_URL", "doc.css",
           "gitiles.PRETTIFY_CSS_URL", "prettify/prettify.css");

   protected static Function<String, URL> fileUrlMapper() {
     return fileUrlMapper("");
   }

   protected static Function<String, URL> fileUrlMapper(String prefix) {
     checkNotNull(prefix);
     return filename -> {
       if (filename == null) {
         return null;
       }
       try {
         return new File(prefix + filename).toURI().toURL();
       } catch (MalformedURLException e) {
         throw new IllegalArgumentException(e);
       }
     };
   }

   protected ImmutableMap<String, URL> templates;
   protected ImmutableMap<String, String> globals;
   protected final String siteTitle;
   private final ConcurrentMap<String, HashCode> hashes =
       new ConcurrentHashMap<>(SOY_FILENAMES.size());

   protected Renderer(
       Function<String, URL> resourceMapper,
       Map<String, String> globals,
       String staticPrefix,
       Iterable<URL> customTemplates,
       String siteTitle) {
     checkNotNull(staticPrefix, "staticPrefix");

     ImmutableMap.Builder<String, URL> b = ImmutableMap.builder();
     for (String name : SOY_FILENAMES) {
       b.put(name, resourceMapper.apply(name));
     }
     for (URL u : customTemplates) {
       b.put(u.toString(), u);
     }
     templates = b.build();

     Map<String, String> allGlobals = Maps.newHashMap();
     for (Map.Entry<String, String> e : STATIC_URL_GLOBALS.entrySet()) {
       allGlobals.put(e.getKey(), staticPrefix + e.getValue());
     }
     allGlobals.putAll(globals);
     this.globals = ImmutableMap.copyOf(allGlobals);
     this.siteTitle = siteTitle;
   }

   public HashCode getTemplateHash(String soyFile) {
     HashCode h = hashes.get(soyFile);
     if (h == null) {
       h = computeTemplateHash(soyFile);
       hashes.put(soyFile, h);
     }
     return h;
   }

   HashCode computeTemplateHash(String soyFile) {
     URL u = templates.get(soyFile);
     checkState(u != null, "Missing Soy template %s", soyFile);

     Hasher h = Hashing.murmur3_128().newHasher();
     try (InputStream is = u.openStream();
         OutputStream os = Funnels.asOutputStream(h)) {
       ByteStreams.copy(is, os);
     } catch (IOException e) {
       throw new IllegalStateException("Missing Soy template " + soyFile, e);
     }
     return h.hash();
   }

   void renderHtml(
       HttpServletRequest req, HttpServletResponse res, String templateName, Map<String, ?> soyData)
       throws IOException {
     res.setContentType("text/html");
     res.setCharacterEncoding("UTF-8");
     byte[] data =
         newRenderer(templateName, Optional.of(req))
             .setData(soyData)
             .renderHtml()
             .get()
             .toString()
             .getBytes(UTF_8);
     if (BaseServlet.acceptsGzipEncoding(req)) {
       res.addHeader(HttpHeaders.VARY, HttpHeaders.ACCEPT_ENCODING);
       res.setHeader(HttpHeaders.CONTENT_ENCODING, "gzip");
       data = BaseServlet.gzip(data);
     }
     res.setContentLength(data.length);
     res.getOutputStream().write(data);
   }

   OutputStream renderHtmlStreaming(
       HttpServletRequest req, HttpServletResponse res, String templateName, Map<String, ?> soyData)
       throws IOException {
     return renderHtmlStreaming(req, res, false, templateName, soyData);
   }

   OutputStream renderHtmlStreaming(
       HttpServletRequest req,
       HttpServletResponse res,
       boolean gzip,
       String templateName,
       Map<String, ?> soyData)
       throws IOException {
     String html =
         newRenderer(templateName, Optional.of(req)).setData(soyData).renderHtml().get().toString();
     int id = html.indexOf(PLACEHOLDER);
     checkArgument(id >= 0, "Template must contain %s", PLACEHOLDER);

     int lt = html.lastIndexOf('<', id);
     int gt = html.indexOf('>', id + PLACEHOLDER.length());

     OutputStream out = gzip ? new GZIPOutputStream(res.getOutputStream()) : res.getOutputStream();
     out.write(html.substring(0, lt).getBytes(UTF_8));
     out.flush();

     byte[] tail = html.substring(gt + 1).getBytes(UTF_8);
     return new OutputStream() {
       @Override
       public void write(byte[] b, int off, int len) throws IOException {
         out.write(b, off, len);
       }

       @Override
       public void write(int b) throws IOException {
         out.write(b);
       }

       @Override
       public void flush() throws IOException {
         out.flush();
       }

       @Override
       public void close() throws IOException {
         try (OutputStream o = out) {
           o.write(tail);
         }
       }
     };
   }

   SoySauce.Renderer newRenderer(String templateName) {
     return newRenderer(templateName, Optional.empty());
   }

   SoySauce.Renderer newRenderer(String templateName, Optional<HttpServletRequest> req) {
     ImmutableMap.Builder<String, Object> staticUrls = ImmutableMap.builder();
     for (String key : STATIC_URL_GLOBALS.keySet()) {
       staticUrls.put(
           key.replaceFirst("^gitiles\\.", ""),
           LegacyConversions.riskilyAssumeTrustedResourceUrl(globals.get(key)));
     }
     ImmutableMap.Builder<String, Object> ij =
         ImmutableMap.<String, Object>builder()
             .put("staticUrls", staticUrls.build())
             .put("SITE_TITLE", siteTitle);
     Optional<String> nonce = req.map((r) -> (String) r.getAttribute("nonce"));
     if (nonce.isPresent()) {
       ij.put("csp_nonce", nonce.get());
     }
     return getSauce().renderTemplate(templateName).setIj(ij.build());
   }

   protected abstract SoySauce getSauce();

   /**
    * Give a resource URL of a soy template file, returns the import path for use in a Soy import
    * statement.
    */
   protected String toSoySrcPath(URL templateUrl) {
     String filePath = templateUrl.getPath();
     String fileName = filePath.substring(filePath.lastIndexOf('/') + 1);
     return "com/google/gitiles/templates/" + fileName;
   }
 }
	// Copyright 2012 Google Inc. 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 com.google.gitiles;

	import static com.google.common.base.Preconditions.checkArgument;
	import static com.google.common.base.Preconditions.checkNotNull;
	import static com.google.common.base.Preconditions.checkState;
	import static java.nio.charset.StandardCharsets.UTF_8;

	import com.google.common.collect.ImmutableList;
	import com.google.common.collect.ImmutableMap;
	import com.google.common.collect.Maps;
	import com.google.common.hash.Funnels;
	import com.google.common.hash.HashCode;
	import com.google.common.hash.Hasher;
	import com.google.common.hash.Hashing;
	import com.google.common.html.types.LegacyConversions;
	import com.google.common.io.ByteStreams;
	import com.google.common.net.HttpHeaders;
	import com.google.template.soy.jbcsrc.api.SoySauce;
	import java.io.File;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.OutputStream;
	import java.net.MalformedURLException;
	import java.net.URL;
	import java.util.Map;
	import java.util.Optional;
	import java.util.concurrent.ConcurrentHashMap;
	import java.util.concurrent.ConcurrentMap;
	import java.util.function.Function;
	import java.util.zip.GZIPOutputStream;
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;

	/**
	* Renderer for Soy templates used by Gitiles.
	*
	* <p>Most callers should not use the methods in this class directly, and instead use one of the
	* HTML methods in {@link BaseServlet}.
	*/
	public abstract class Renderer {
	// Must match .streamingPlaceholder.
	private static final String PLACEHOLDER = "id=\"STREAMED-OUTPUT-BLOCK\"";

	private static final ImmutableList<String> SOY_FILENAMES =
	ImmutableList.of(
	"BlameDetail.soy",
	"Common.soy",
	"DiffDetail.soy",
	"Doc.soy",
	"Error.soy",
	"HostIndex.soy",
	"LogDetail.soy",
	"ObjectDetail.soy",
	"PathDetail.soy",
	"RefList.soy",
	"RevisionDetail.soy",
	"RepositoryIndex.soy");

	public static final ImmutableMap<String, String> STATIC_URL_GLOBALS =
	ImmutableMap.of(
	"gitiles.BASE_CSS_URL", "base.css",
	"gitiles.DOC_CSS_URL", "doc.css",
	"gitiles.PRETTIFY_CSS_URL", "prettify/prettify.css");

	protected static Function<String, URL> fileUrlMapper() {
	return fileUrlMapper("");
	}

	protected static Function<String, URL> fileUrlMapper(String prefix) {
	checkNotNull(prefix);
	return filename -> {
	if (filename == null) {
	return null;
	}
	try {
	return new File(prefix + filename).toURI().toURL();
	} catch (MalformedURLException e) {
	throw new IllegalArgumentException(e);
	}
	};
	}

	protected ImmutableMap<String, URL> templates;
	protected ImmutableMap<String, String> globals;
	protected final String siteTitle;
	private final ConcurrentMap<String, HashCode> hashes =
	new ConcurrentHashMap<>(SOY_FILENAMES.size());

	protected Renderer(
	Function<String, URL> resourceMapper,
	Map<String, String> globals,
	String staticPrefix,
	Iterable<URL> customTemplates,
	String siteTitle) {
	checkNotNull(staticPrefix, "staticPrefix");

	ImmutableMap.Builder<String, URL> b = ImmutableMap.builder();
	for (String name : SOY_FILENAMES) {
	b.put(name, resourceMapper.apply(name));
	}
	for (URL u : customTemplates) {
	b.put(u.toString(), u);
	}
	templates = b.build();

	Map<String, String> allGlobals = Maps.newHashMap();
	for (Map.Entry<String, String> e : STATIC_URL_GLOBALS.entrySet()) {
	allGlobals.put(e.getKey(), staticPrefix + e.getValue());
	}
	allGlobals.putAll(globals);
	this.globals = ImmutableMap.copyOf(allGlobals);
	this.siteTitle = siteTitle;
	}

	public HashCode getTemplateHash(String soyFile) {
	HashCode h = hashes.get(soyFile);
	if (h == null) {
	h = computeTemplateHash(soyFile);
	hashes.put(soyFile, h);
	}
	return h;
	}

	HashCode computeTemplateHash(String soyFile) {
	URL u = templates.get(soyFile);
	checkState(u != null, "Missing Soy template %s", soyFile);

	Hasher h = Hashing.murmur3_128().newHasher();
	try (InputStream is = u.openStream();
	OutputStream os = Funnels.asOutputStream(h)) {
	ByteStreams.copy(is, os);
	} catch (IOException e) {
	throw new IllegalStateException("Missing Soy template " + soyFile, e);
	}
	return h.hash();
	}

	void renderHtml(
	HttpServletRequest req, HttpServletResponse res, String templateName, Map<String, ?> soyData)
	throws IOException {
	res.setContentType("text/html");
	res.setCharacterEncoding("UTF-8");
	byte[] data =
	newRenderer(templateName, Optional.of(req))
	.setData(soyData)
	.renderHtml()
	.get()
	.toString()
	.getBytes(UTF_8);
	if (BaseServlet.acceptsGzipEncoding(req)) {
	res.addHeader(HttpHeaders.VARY, HttpHeaders.ACCEPT_ENCODING);
	res.setHeader(HttpHeaders.CONTENT_ENCODING, "gzip");
	data = BaseServlet.gzip(data);
	}
	res.setContentLength(data.length);
	res.getOutputStream().write(data);
	}

	OutputStream renderHtmlStreaming(
	HttpServletRequest req, HttpServletResponse res, String templateName, Map<String, ?> soyData)
	throws IOException {
	return renderHtmlStreaming(req, res, false, templateName, soyData);
	}

	OutputStream renderHtmlStreaming(
	HttpServletRequest req,
	HttpServletResponse res,
	boolean gzip,
	String templateName,
	Map<String, ?> soyData)
	throws IOException {
	String html =
	newRenderer(templateName, Optional.of(req)).setData(soyData).renderHtml().get().toString();
	int id = html.indexOf(PLACEHOLDER);
	checkArgument(id >= 0, "Template must contain %s", PLACEHOLDER);

	int lt = html.lastIndexOf('<', id);
	int gt = html.indexOf('>', id + PLACEHOLDER.length());

	OutputStream out = gzip ? new GZIPOutputStream(res.getOutputStream()) : res.getOutputStream();
	out.write(html.substring(0, lt).getBytes(UTF_8));
	out.flush();

	byte[] tail = html.substring(gt + 1).getBytes(UTF_8);
	return new OutputStream() {
	@Override
	public void write(byte[] b, int off, int len) throws IOException {
	out.write(b, off, len);
	}

	@Override
	public void write(int b) throws IOException {
	out.write(b);
	}

	@Override
	public void flush() throws IOException {
	out.flush();
	}

	@Override
	public void close() throws IOException {
	try (OutputStream o = out) {
	o.write(tail);
	}
	}
	};
	}

	SoySauce.Renderer newRenderer(String templateName) {
	return newRenderer(templateName, Optional.empty());
	}

	SoySauce.Renderer newRenderer(String templateName, Optional<HttpServletRequest> req) {
	ImmutableMap.Builder<String, Object> staticUrls = ImmutableMap.builder();
	for (String key : STATIC_URL_GLOBALS.keySet()) {
	staticUrls.put(
	key.replaceFirst("^gitiles\\.", ""),
	LegacyConversions.riskilyAssumeTrustedResourceUrl(globals.get(key)));
	}
	ImmutableMap.Builder<String, Object> ij =
	ImmutableMap.<String, Object>builder()
	.put("staticUrls", staticUrls.build())
	.put("SITE_TITLE", siteTitle);
	Optional<String> nonce = req.map((r) -> (String) r.getAttribute("nonce"));
	if (nonce.isPresent()) {
	ij.put("csp_nonce", nonce.get());
	}
	return getSauce().renderTemplate(templateName).setIj(ij.build());
	}

	protected abstract SoySauce getSauce();

	/**
	* Give a resource URL of a soy template file, returns the import path for use in a Soy import
	* statement.
	*/
	protected String toSoySrcPath(URL templateUrl) {
	String filePath = templateUrl.getPath();
	String fileName = filePath.substring(filePath.lastIndexOf('/') + 1);
	return "com/google/gitiles/templates/" + fileName;
	}
	}