下面列出了 io.netty.handler.codec.dns.DnsSection #io.netty.handler.codec.dns.DnsResponse 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
DnsQueryContext(DnsNameResolver parent,
InetSocketAddress nameServerAddr,
DnsQuestion question,
DnsRecord[] additionals,
Promise<AddressedEnvelope<DnsResponse, InetSocketAddress>> promise) {
this.parent = checkNotNull(parent, "parent");
this.nameServerAddr = checkNotNull(nameServerAddr, "nameServerAddr");
this.question = checkNotNull(question, "question");
this.additionals = checkNotNull(additionals, "additionals");
this.promise = checkNotNull(promise, "promise");
recursionDesired = parent.isRecursionDesired();
id = parent.queryContextManager.add(this);
if (parent.isOptResourceEnabled()) {
optResource = new AbstractDnsOptPseudoRrRecord(parent.maxPayloadSize(), 0, 0) {
// We may want to remove this in the future and let the user just specify the opt record in the query.
};
} else {
optResource = null;
}
}
private void setSuccess(AddressedEnvelope<? extends DnsResponse, InetSocketAddress> envelope) {
parent.queryContextManager.remove(nameServerAddr(), id);
// Cancel the timeout task.
final ScheduledFuture<?> timeoutFuture = this.timeoutFuture;
if (timeoutFuture != null) {
timeoutFuture.cancel(false);
}
Promise<AddressedEnvelope<DnsResponse, InetSocketAddress>> promise = this.promise;
if (promise.setUncancellable()) {
@SuppressWarnings("unchecked")
AddressedEnvelope<DnsResponse, InetSocketAddress> castResponse =
(AddressedEnvelope<DnsResponse, InetSocketAddress>) envelope.retain();
if (!promise.trySuccess(castResponse)) {
// We failed to notify the promise as it was failed before, thus we need to release the envelope
envelope.release();
}
}
}
private static Map<String, String> buildAliasMap(DnsResponse response) {
final int answerCount = response.count(DnsSection.ANSWER);
Map<String, String> cnames = null;
for (int i = 0; i < answerCount; i ++) {
final DnsRecord r = response.recordAt(DnsSection.ANSWER, i);
final DnsRecordType type = r.type();
if (type != DnsRecordType.CNAME) {
continue;
}
if (!(r instanceof DnsRawRecord)) {
continue;
}
final ByteBuf recordContent = ((ByteBufHolder) r).content();
final String domainName = decodeDomainName(recordContent);
if (domainName == null) {
continue;
}
if (cnames == null) {
cnames = new HashMap<String, String>(min(8, answerCount));
}
cnames.put(r.name().toLowerCase(Locale.US), domainName.toLowerCase(Locale.US));
}
return cnames != null? cnames : Collections.<String, String>emptyMap();
}
final Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query0(
InetSocketAddress nameServerAddr, DnsQuestion question,
DnsRecord[] additionals,
ChannelPromise writePromise,
Promise<AddressedEnvelope<? extends DnsResponse, InetSocketAddress>> promise) {
assert !writePromise.isVoid();
final Promise<AddressedEnvelope<DnsResponse, InetSocketAddress>> castPromise = cast(
checkNotNull(promise, "promise"));
try {
new DnsQueryContext(this, nameServerAddr, question, additionals, castPromise).query(writePromise);
return castPromise;
} catch (Exception e) {
return castPromise.setFailure(e);
}
}
public TestDnsServer(Map<DnsQuestion, DnsResponse> responses,
@Nullable ChannelInboundHandlerAdapter beforeDnsServerHandler) {
this.responses = ImmutableMap.copyOf(responses);
final Bootstrap b = new Bootstrap();
b.channel(TransportType.datagramChannelType(CommonPools.workerGroup()));
b.group(CommonPools.workerGroup());
b.handler(new ChannelInitializer() {
@Override
protected void initChannel(Channel ch) throws Exception {
final ChannelPipeline p = ch.pipeline();
p.addLast(new DatagramDnsQueryDecoder());
p.addLast(new DatagramDnsResponseEncoder());
if (beforeDnsServerHandler != null) {
p.addLast(beforeDnsServerHandler);
}
p.addLast(new DnsServerHandler());
}
});
channel = b.bind(NetUtil.LOCALHOST, 0).syncUninterruptibly().channel();
}
void finish(AddressedEnvelope<? extends DnsResponse, InetSocketAddress> envelope) {
final DnsResponse res = envelope.content();
if (res.count(DnsSection.QUESTION) != 1) {
logger.warn("Received a DNS response with invalid number of questions: {}", envelope);
return;
}
if (!question().equals(res.recordAt(DnsSection.QUESTION))) {
logger.warn("Received a mismatching DNS response: {}", envelope);
return;
}
setSuccess(envelope);
}
void onResponse(final DnsServerAddressStream nameServerAddrStream, final int nameServerAddrStreamIndex,
final DnsQuestion question, AddressedEnvelope<DnsResponse, InetSocketAddress> envelope,
final DnsQueryLifecycleObserver queryLifecycleObserver,
Promise<T> promise) {
try {
final DnsResponse res = envelope.content();
final DnsResponseCode code = res.code();
if (code == DnsResponseCode.NOERROR) {
if (handleRedirect(question, envelope, queryLifecycleObserver, promise)) {
// Was a redirect so return here as everything else is handled in handleRedirect(...)
return;
}
final DnsRecordType type = question.type();
if (type == DnsRecordType.A || type == DnsRecordType.AAAA) {
onResponseAorAAAA(type, question, envelope, queryLifecycleObserver, promise);
} else if (type == DnsRecordType.CNAME) {
onResponseCNAME(question, envelope, queryLifecycleObserver, promise);
} else {
queryLifecycleObserver.queryFailed(UNRECOGNIZED_TYPE_QUERY_FAILED_EXCEPTION);
}
return;
}
// Retry with the next server if the server did not tell us that the domain does not exist.
if (code != DnsResponseCode.NXDOMAIN) {
query(nameServerAddrStream, nameServerAddrStreamIndex + 1, question,
queryLifecycleObserver.queryNoAnswer(code), promise, null);
} else {
queryLifecycleObserver.queryFailed(NXDOMAIN_QUERY_FAILED_EXCEPTION);
}
} finally {
ReferenceCountUtil.safeRelease(envelope);
}
}
/**
* Returns the {@code {@link AuthoritativeNameServerList} which were included in {@link DnsSection#AUTHORITY}
* or {@code null} if non are found.
*/
private static AuthoritativeNameServerList extractAuthoritativeNameServers(String questionName, DnsResponse res) {
int authorityCount = res.count(DnsSection.AUTHORITY);
if (authorityCount == 0) {
return null;
}
AuthoritativeNameServerList serverNames = new AuthoritativeNameServerList(questionName);
for (int i = 0; i < authorityCount; i++) {
serverNames.add(res.recordAt(DnsSection.AUTHORITY, i));
}
return serverNames;
}
private void onResponseCNAME(
DnsQuestion question, AddressedEnvelope<DnsResponse, InetSocketAddress> response,
Map<String, String> cnames, final DnsQueryLifecycleObserver queryLifecycleObserver,
Promise<T> promise) {
// Resolve the host name in the question into the real host name.
final String name = question.name().toLowerCase(Locale.US);
String resolved = name;
boolean found = false;
while (!cnames.isEmpty()) { // Do not attempt to call Map.remove() when the Map is empty
// because it can be Collections.emptyMap()
// whose remove() throws a UnsupportedOperationException.
final String next = cnames.remove(resolved);
if (next != null) {
found = true;
resolved = next;
} else {
break;
}
}
if (found) {
followCname(question, resolved, queryLifecycleObserver, promise);
} else {
queryLifecycleObserver.queryFailed(CNAME_NOT_FOUND_QUERY_FAILED_EXCEPTION);
}
}
/**
* Sends a DNS query with the specified question using the specified name server list.
*/
public Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query(
InetSocketAddress nameServerAddr, DnsQuestion question) {
return query0(nameServerAddr, question, EMPTY_ADDITIONALS,
ch.eventLoop().<AddressedEnvelope<? extends DnsResponse, InetSocketAddress>>newPromise());
}
/**
* Sends a DNS query with the specified question with additional records using the specified name server list.
*/
public Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query(
InetSocketAddress nameServerAddr, DnsQuestion question, Iterable<DnsRecord> additionals) {
return query0(nameServerAddr, question, toArray(additionals, false),
ch.eventLoop().<AddressedEnvelope<? extends DnsResponse, InetSocketAddress>>newPromise());
}
/**
* Sends a DNS query with the specified question using the specified name server list.
*/
public Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query(
InetSocketAddress nameServerAddr, DnsQuestion question,
Promise<AddressedEnvelope<? extends DnsResponse, InetSocketAddress>> promise) {
return query0(nameServerAddr, question, EMPTY_ADDITIONALS, promise);
}
/**
* Sends a DNS query with the specified question with additional records using the specified name server list.
*/
public Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query(
InetSocketAddress nameServerAddr, DnsQuestion question,
Iterable<DnsRecord> additionals,
Promise<AddressedEnvelope<? extends DnsResponse, InetSocketAddress>> promise) {
return query0(nameServerAddr, question, toArray(additionals, false), promise);
}
@Override
public void close() {
if (!channel.isOpen()) {
return;
}
channel.close().syncUninterruptibly();
responses.values().forEach(DnsResponse::release);
}
@Override
public void operationComplete(Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> future) {
if (future.isSuccess()) {
future.getNow().release();
}
}
private void query(final DnsServerAddressStream nameServerAddrStream,
final int nameServerAddrStreamIndex,
final DnsQuestion question,
final DnsQueryLifecycleObserver queryLifecycleObserver,
final Promise<T> promise,
final Throwable cause) {
if (nameServerAddrStreamIndex >= nameServerAddrStream.size() || allowedQueries == 0 || promise.isCancelled()) {
tryToFinishResolve(nameServerAddrStream, nameServerAddrStreamIndex, question, queryLifecycleObserver,
promise, cause);
return;
}
--allowedQueries;
final InetSocketAddress nameServerAddr = nameServerAddrStream.next();
final ChannelPromise writePromise = parent.ch.newPromise();
final Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> f = parent.query0(
nameServerAddr, question, additionals, writePromise,
parent.ch.eventLoop().<AddressedEnvelope<? extends DnsResponse, InetSocketAddress>>newPromise());
queriesInProgress.add(f);
queryLifecycleObserver.queryWritten(nameServerAddr, writePromise);
f.addListener(new FutureListener<AddressedEnvelope<DnsResponse, InetSocketAddress>>() {
@Override
public void operationComplete(Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> future) {
queriesInProgress.remove(future);
if (promise.isDone() || future.isCancelled()) {
queryLifecycleObserver.queryCancelled(allowedQueries);
// Check if we need to release the envelope itself. If the query was cancelled the getNow() will
// return null as well as the Future will be failed with a CancellationException.
AddressedEnvelope<DnsResponse, InetSocketAddress> result = future.getNow();
if (result != null) {
result.release();
}
return;
}
final Throwable queryCause = future.cause();
try {
if (queryCause == null) {
onResponse(nameServerAddrStream, nameServerAddrStreamIndex, question, future.getNow(),
queryLifecycleObserver, promise);
} else {
// Server did not respond or I/O error occurred; try again.
queryLifecycleObserver.queryFailed(queryCause);
query(nameServerAddrStream, nameServerAddrStreamIndex + 1, question, promise, queryCause);
}
} finally {
tryToFinishResolve(nameServerAddrStream, nameServerAddrStreamIndex, question,
// queryLifecycleObserver has already been terminated at this point so we must
// not allow it to be terminated again by tryToFinishResolve.
NoopDnsQueryLifecycleObserver.INSTANCE,
promise, queryCause);
}
}
});
}
/**
* Handles a redirect answer if needed and returns {@code true} if a redirect query has been made.
*/
private boolean handleRedirect(
DnsQuestion question, AddressedEnvelope<DnsResponse, InetSocketAddress> envelope,
final DnsQueryLifecycleObserver queryLifecycleObserver, Promise<T> promise) {
final DnsResponse res = envelope.content();
// Check if we have answers, if not this may be an non authority NS and so redirects must be handled.
if (res.count(DnsSection.ANSWER) == 0) {
AuthoritativeNameServerList serverNames = extractAuthoritativeNameServers(question.name(), res);
if (serverNames != null) {
List<InetSocketAddress> nameServers = new ArrayList<InetSocketAddress>(serverNames.size());
int additionalCount = res.count(DnsSection.ADDITIONAL);
for (int i = 0; i < additionalCount; i++) {
final DnsRecord r = res.recordAt(DnsSection.ADDITIONAL, i);
if (r.type() == DnsRecordType.A && !parent.supportsARecords() ||
r.type() == DnsRecordType.AAAA && !parent.supportsAAAARecords()) {
continue;
}
final String recordName = r.name();
AuthoritativeNameServer authoritativeNameServer =
serverNames.remove(recordName);
if (authoritativeNameServer == null) {
// Not a server we are interested in.
continue;
}
InetAddress resolved = parseAddress(r, recordName);
if (resolved == null) {
// Could not parse it, move to the next.
continue;
}
nameServers.add(new InetSocketAddress(resolved, parent.dnsRedirectPort(resolved)));
addNameServerToCache(authoritativeNameServer, resolved, r.timeToLive());
}
if (!nameServers.isEmpty()) {
query(parent.uncachedRedirectDnsServerStream(nameServers), 0, question,
queryLifecycleObserver.queryRedirected(unmodifiableList(nameServers)), promise, null);
return true;
}
}
}
return false;
}
private void onResponseCNAME(DnsQuestion question, AddressedEnvelope<DnsResponse, InetSocketAddress> envelope,
final DnsQueryLifecycleObserver queryLifecycleObserver,
Promise<T> promise) {
onResponseCNAME(question, envelope, buildAliasMap(envelope.content()), queryLifecycleObserver, promise);
}
/**
* Sends a DNS query with the specified question.
*/
public Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query(DnsQuestion question) {
return query(nextNameServerAddress(), question);
}
/**
* Sends a DNS query with the specified question with additional records.
*/
public Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query(
DnsQuestion question, Iterable<DnsRecord> additionals) {
return query(nextNameServerAddress(), question, additionals);
}
/**
* Sends a DNS query with the specified question.
*/
public Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query(
DnsQuestion question, Promise<AddressedEnvelope<? extends DnsResponse, InetSocketAddress>> promise) {
return query(nextNameServerAddress(), question, Collections.<DnsRecord>emptyList(), promise);
}
final Future<AddressedEnvelope<DnsResponse, InetSocketAddress>> query0(
InetSocketAddress nameServerAddr, DnsQuestion question,
DnsRecord[] additionals,
Promise<AddressedEnvelope<? extends DnsResponse, InetSocketAddress>> promise) {
return query0(nameServerAddr, question, additionals, ch.newPromise(), promise);
}
@SuppressWarnings("unchecked")
private static Promise<AddressedEnvelope<DnsResponse, InetSocketAddress>> cast(Promise<?> promise) {
return (Promise<AddressedEnvelope<DnsResponse, InetSocketAddress>>) promise;
}
private static void queryMx(
DnsNameResolver resolver,
Map<String, Future<AddressedEnvelope<DnsResponse, InetSocketAddress>>> futures,
String hostname) throws Exception {
futures.put(hostname, resolver.query(new DefaultDnsQuestion(hostname, DnsRecordType.MX)));
}
public TestDnsServer(Map<DnsQuestion, DnsResponse> responses) {
this(responses, null);
}
public void setResponses(Map<DnsQuestion, DnsResponse> responses) {
this.responses.values().forEach(DnsResponse::release);
this.responses = ImmutableMap.copyOf(responses);
}
private void resolveAddress() {
boolean debug = getFlag(BuiltinFlags.PRINT_DEBUG, false);
String name = this.getPacketProtocol().getSRVRecordPrefix() + "._tcp." + this.getHost();
if(debug) {
System.out.println("[PacketLib] Attempting SRV lookup for \"" + name + "\".");
}
AddressedEnvelope<DnsResponse, InetSocketAddress> envelope = null;
try(DnsNameResolver resolver = new DnsNameResolverBuilder(this.group.next())
.channelType(NioDatagramChannel.class)
.build()) {
envelope = resolver.query(new DefaultDnsQuestion(name, DnsRecordType.SRV)).get();
DnsResponse response = envelope.content();
if(response.count(DnsSection.ANSWER) > 0) {
DefaultDnsRawRecord record = response.recordAt(DnsSection.ANSWER, 0);
if(record.type() == DnsRecordType.SRV) {
ByteBuf buf = record.content();
buf.skipBytes(4); // Skip priority and weight.
int port = buf.readUnsignedShort();
String host = DefaultDnsRecordDecoder.decodeName(buf);
if(host.endsWith(".")) {
host = host.substring(0, host.length() - 1);
}
if(debug) {
System.out.println("[PacketLib] Found SRV record containing \"" + host + ":" + port + "\".");
}
this.host = host;
this.port = port;
} else if(debug) {
System.out.println("[PacketLib] Received non-SRV record in response.");
}
} else if(debug) {
System.out.println("[PacketLib] No SRV record found.");
}
} catch(Exception e) {
if(debug) {
System.out.println("[PacketLib] Failed to resolve SRV record.");
e.printStackTrace();
}
} finally {
if(envelope != null) {
envelope.release();
}
}
}