@Test
public void testZeroCrawlDelay() {
FetcherPolicy policy =
new FetcherPolicy(
FetcherPolicy.NO_MIN_RESPONSE_RATE,
FetcherPolicy.DEFAULT_MAX_CONTENT_SIZE,
FetcherPolicy.NO_CRAWL_END_TIME,
0,
FetcherPolicy.DEFAULT_MAX_REDIRECTS);
try {
FetchRequest request = policy.getFetchRequest(100);
Assert.assertEquals(100, request.getNumUrls());
Assert.assertTrue(request.getNextRequestTime() <= System.currentTimeMillis());
} catch (Exception e) {
Assert.fail("Exception: " + e.getMessage());
}
}
public static void main(String[] args) throws IOException {
DemoWebMiningOptions options = new DemoWebMiningOptions();
CmdLineParser parser = new CmdLineParser(options);
try {
parser.parseArgument(args);
} catch (CmdLineException e) {
System.err.println(e.getMessage());
printUsageAndExit(parser);
}
// Build and run the flow.
try {
Path workingDirPath = new Path(options.getWorkingDir());
JobConf conf = new JobConf();
FileSystem fs = workingDirPath.getFileSystem(conf);
setupWorkingDir(fs, workingDirPath, CrawlConfig.SEED_URLS_FILENAME);
Path latestDirPath = CrawlDirUtils.findLatestLoopDir(fs, workingDirPath);
if (latestDirPath == null) {
error("No previous cycle output dirs exist in " + workingDirPath, parser);
}
Path crawlDbPath = new Path(latestDirPath, CrawlConfig.CRAWLDB_SUBDIR_NAME);
UserAgent userAgent =
new UserAgent(options.getAgentName(), CrawlConfig.EMAIL_ADDRESS, CrawlConfig.WEB_ADDRESS);
FetcherPolicy fetcherPolicy = new FetcherPolicy();
fetcherPolicy.setCrawlDelay(CrawlConfig.DEFAULT_CRAWL_DELAY);
fetcherPolicy.setMaxContentSize(CrawlConfig.MAX_CONTENT_SIZE);
fetcherPolicy.setFetcherMode(FetcherMode.EFFICIENT);
// We only care about mime types that the Tika HTML parser can handle,
// so restrict it to the same.
Set<String> validMimeTypes = new HashSet<String>();
Set<MediaType> supportedTypes = new HtmlParser().getSupportedTypes(new ParseContext());
for (MediaType supportedType : supportedTypes) {
validMimeTypes.add(
String.format("%s/%s", supportedType.getType(), supportedType.getSubtype()));
}
fetcherPolicy.setValidMimeTypes(validMimeTypes);
// Let's limit our crawl to two loops
for (int curLoop = 1; curLoop <= 2; curLoop++) {
Path curLoopDirPath = CrawlDirUtils.makeLoopDir(fs, workingDirPath, curLoop);
Flow flow =
DemoWebMiningWorkflow.createWebMiningWorkflow(
crawlDbPath, curLoopDirPath, fetcherPolicy, userAgent, options, curLoop == 1);
flow.complete();
// Update crawlDbPath to point to the latest crawl db
crawlDbPath = new Path(curLoopDirPath, CrawlConfig.CRAWLDB_SUBDIR_NAME);
}
} catch (Exception e) {
System.err.println("Exception running job: " + e.getMessage());
e.printStackTrace(System.err);
System.exit(-1);
}
}
@Override
public void operate(FlowProcess process, BufferCall<NullContext> buffCall) {
QueuedValues values = new QueuedValues(buffCall.getArgumentsIterator());
_collector = buffCall.getOutputCollector();
FetcherPolicy fetcherPolicy = _fetcher.getFetcherPolicy();
// Each value is a PreFetchedDatum that contains a set of URLs to fetch in one request from
// a single server, plus other values needed to set state properly.
while (!Thread.interrupted() && !fetcherPolicy.isTerminateFetch() && !values.isEmpty()) {
FetchSetDatum datum = values.nextOrNull(_fetcherMode);
try {
if (datum == null) {
trace("Nothing ready to fetch, sleeping...");
process.keepAlive();
Thread.sleep(NOTHING_TO_FETCH_SLEEP_TIME);
} else {
List<ScoredUrlDatum> urls = datum.getUrls();
String ref = datum.getGroupingRef();
trace("Processing %d URLs for %s", urls.size(), ref);
Runnable doFetch = new FetchTask(this, _fetcher, urls, ref);
if (datum.isLastList()) {
makeActive(ref, 0L);
trace("Executing fetch of %d URLs from %s (last batch)", urls.size(), ref);
} else {
Long nextFetchTime = System.currentTimeMillis() + datum.getFetchDelay();
makeActive(ref, nextFetchTime);
trace(
"Executing fetch of %d URLs from %s (next fetch time %d)",
urls.size(), ref, nextFetchTime);
}
long startTime = System.currentTimeMillis();
try {
_executor.execute(doFetch);
} catch (RejectedExecutionException e) {
// should never happen.
LOGGER.error("Fetch pool rejected our fetch list for " + ref);
finished(ref);
skipUrls(
urls,
UrlStatus.SKIPPED_DEFERRED,
String.format("Execution rejection skipped %d URLs", urls.size()));
}
// Adjust for how long it took to get the request queued.
adjustActive(ref, System.currentTimeMillis() - startTime);
}
} catch (InterruptedException e) {
LOGGER.warn("FetchBuffer interrupted!");
Thread.currentThread().interrupt();
}
}
// Skip all URLs that we've got left.
if (!values.isEmpty()) {
trace("Found unprocessed URLs");
UrlStatus status =
Thread.interrupted() ? UrlStatus.SKIPPED_INTERRUPTED : UrlStatus.SKIPPED_TIME_LIMIT;
while (!values.isEmpty()) {
FetchSetDatum datum = values.drain();
List<ScoredUrlDatum> urls = datum.getUrls();
trace(
"Skipping %d urls from %s (e.g. %s) ",
urls.size(), datum.getGroupingRef(), urls.get(0).getUrl());
skipUrls(urls, status, null);
}
}
}
