add PhantomJSDownloader

webmagic-core/src/main/java/us/codecraft/webmagic/downloader/PhantomJSDownloader.java

+package us.codecraft.webmagic.downloader;
+
+import org.apache.http.annotation.ThreadSafe;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import us.codecraft.webmagic.Page;
+import us.codecraft.webmagic.Request;
+import us.codecraft.webmagic.Task;
+import us.codecraft.webmagic.selector.PlainText;
+
+import java.io.*;
+
+/**
+ * this downloader is used to download pages which need to render the javascript
+ *
+ * @author dolphineor@gmail.com
+ * @version 0.5.3
+ */
+@ThreadSafe
+public class PhantomJSDownloader extends AbstractDownloader {
+
+    private static Logger logger = LoggerFactory.getLogger(PhantomJSDownloader.class);
+    private static String phantomJSPath;
+
+    private int retryNum;
+    private int threadNum;
+
+    public PhantomJSDownloader() {
+        PhantomJSDownloader.phantomJSPath = new File(this.getClass().getResource("/").getPath()).getPath() + System.getProperty("file.separator") + "crawl.js ";
+    }
+
+    @Override
+    public Page download(Request request, Task task) {
+        if (logger.isInfoEnabled()) {
+            logger.info("downloading page: " + request.getUrl());
+        }
+        String content = getPage(request);
+        if (content.contains("HTTP request failed")) {
+            for (int i = 1; i <= getRetryNum(); i++) {
+                content = getPage(request);
+                if (!content.contains("HTTP request failed")) {
+                    break;
+                }
+            }
+            if (content.contains("HTTP request failed")) {
+                //when failed
+                Page page = new Page();
+                page.setRequest(request);
+                return page;
+            }
+        }
+
+        Page page = new Page();
+        page.setRawText(content);
+        page.setUrl(new PlainText(request.getUrl()));
+        page.setRequest(request);
+        page.setStatusCode(200);
+        return page;
+    }
+
+    @Override
+    public void setThread(int threadNum) {
+        this.threadNum = threadNum;
+    }
+
+    protected String getPage(Request request) {
+        try {
+            String url = request.getUrl();
+            Runtime runtime = Runtime.getRuntime();
+            Process process = runtime.exec("phantomjs " + phantomJSPath + url);
+            InputStream is = process.getInputStream();
+            BufferedReader br = new BufferedReader(new InputStreamReader(is));
+            StringBuffer stringBuffer = new StringBuffer();
+            String line;
+            while ((line = br.readLine()) != null) {
+                stringBuffer.append(line).append("\n");
+            }
+            return stringBuffer.toString();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+        return null;
+    }
+
+    public int getRetryNum() {
+        return retryNum;
+    }
+
+    public PhantomJSDownloader setRetryNum(int retryNum) {
+        this.retryNum = retryNum;
+        return this;
+    }
+}

webmagic-core/src/main/resources/crawl.js

+var system = require('system');
+var url = system.args[1];
+
+var page = require('webpage').create();
+page.settings.loadImages = false;
+page.settings.resourceTimeout = 5000;
+
+page.open(url, function (status) {
+    if (status != 'success') {
+        console.log("HTTP request failed!");
+    } else {
+        console.log(page.content);
+    }
+
+    page.close();
+    phantom.exit();
+});
\ No newline at end of file

webmagic-samples/src/main/java/us/codecraft/webmagic/samples/PhantomJSPageProcessor.java

+package us.codecraft.webmagic.samples;
+
+import us.codecraft.webmagic.Page;
+import us.codecraft.webmagic.ResultItems;
+import us.codecraft.webmagic.Site;
+import us.codecraft.webmagic.Spider;
+import us.codecraft.webmagic.downloader.PhantomJSDownloader;
+import us.codecraft.webmagic.pipeline.CollectorPipeline;
+import us.codecraft.webmagic.pipeline.ResultItemsCollectorPipeline;
+import us.codecraft.webmagic.processor.PageProcessor;
+
+import java.util.List;
+
+/**
+ * Created by dolphineor on 2014-11-21.
+ * <p/>
+ * 以淘宝为例, 搜索冬装的相关结果
+ */
+public class PhantomJSPageProcessor implements PageProcessor {
+
+    private Site site = Site.me()
+            .setDomain("s.taobao.com")
+            .setCharset("GBK")
+            .addHeader("Referer", "http://www.taobao.com/")
+            .setRetryTimes(3).setSleepTime(1000);
+
+    @Override
+    public void process(Page page) {
+        if (page.getRawText() != null)
+            page.putField("html", page.getRawText());
+    }
+
+    @Override
+    public Site getSite() {
+        return site;
+    }
+
+    public static void main(String[] args) throws Exception {
+        PhantomJSDownloader phantomDownloader = new PhantomJSDownloader().setRetryNum(3);
+
+        CollectorPipeline<ResultItems> collectorPipeline = new ResultItemsCollectorPipeline();
+
+        Spider.create(new PhantomJSPageProcessor())
+                .addUrl("http://s.taobao.com/search?q=%B6%AC%D7%B0&sort=sale-desc") //%B6%AC%D7%B0为冬装的GBK编码
+                .setDownloader(phantomDownloader)
+                .addPipeline(collectorPipeline)
+                .thread((Runtime.getRuntime().availableProcessors() - 1) << 1)
+                .run();
+
+        List<ResultItems> resultItemsList = collectorPipeline.getCollected();
+        System.out.println(resultItemsList.get(0).get("html").toString());
+    }
+
+}

webmagic-samples/src/main/resources/crawl.js

+var system = require('system');
+var url = system.args[1];
+
+var page = require('webpage').create();
+page.settings.loadImages = false;
+page.settings.resourceTimeout = 5000;
+
+page.open(url, function (status) {
+    if (status != 'success') {
+        console.log("HTTP request failed!");
+    } else {
+        console.log(page.content);
+    }
+
+    page.close();
+    phantom.exit();
+});
\ No newline at end of file