Netty5/Resolver/DNS 5.0.0.Alpha5 · io.netty5.resolver.dns.DnsQueryLifecycleObserver

This interface provides visibility into individual DNS queries. The lifecycle of an objects is as follows:

Object creation
queryCancelled(int)

Object creation
queryWritten(InetSocketAddress, Future)
queryRedirected(List) or queryCNAMEd(DnsQuestion) or queryNoAnswer(DnsResponseCode) or queryCancelled(int) or queryFailed(Throwable) or querySucceed()

This interface can be used to track metrics for individual DNS servers. Methods which may lead to another DNS query return an object of type DnsQueryLifecycleObserver. Implementations may use this to build a query tree to understand the "sub queries" generated by a single query.

Method Summary

Modifier and Type	Method and Description
public void	queryCancelled(int The number of queries remaining. queriesRemaining) The query may have been written but it was cancelled at some point.
public DnsQueryLifecycleObserver	Returns: An observer for the new query which we may issue. queryCNAMEd(DnsQuestion the question we would use if we issue a new query. cnameQuestion) The query returned a CNAME which we may attempt to follow with a new query.
public void	queryFailed(Throwable The cause which for the failure. cause) The following criteria are possible: IO Error Server responded with an invalid DNS response Server responded with a valid DNS response, but it didn't progress the resolution
public DnsQueryLifecycleObserver	Returns: An observer for the new query which we may issue. queryNoAnswer(DnsResponseCode the unexpected response code. code) The response to the query didn't provide the expected response code, but it didn't return `DnsResponseCode#NXDOMAIN` so we may try to query again.
public DnsQueryLifecycleObserver	Returns: An observer for the new query which we may issue. queryRedirected(List<InetSocketAddress> The name servers the query has been redirected to. nameServers) The query has been redirected to another list of DNS servers.
public void	querySucceed() The query received the expected results.
public void	queryWritten(InetSocketAddress The DNS server address which the query was sent to. dnsServerAddress, Future<Void> The future which represents the status of the write operation for the DNS query. future) The query has been written.

Method Detail

queryCancelled	back to summary
public void queryCancelled(int queriesRemaining) The query may have been written but it was cancelled at some point. Parameters queriesRemaining:int The number of queries remaining.

queryCancelled

back to summary

public void queryCancelled(int queriesRemaining)

The query may have been written but it was cancelled at some point.

Parameters

queriesRemaining:int: The number of queries remaining.

queryCNAMEd back to summary

queryCNAMEd	back to summary
public DnsQueryLifecycleObserver queryCNAMEd(DnsQuestion cnameQuestion) The query returned a CNAME which we may attempt to follow with a new query. Note that multiple queries may be encountering a CNAME. For example a if both `DnsRecordType#AAAA` and `DnsRecordType#A` are supported we may query for both. Parameters cnameQuestion:DnsQuestion the question we would use if we issue a new query. Returns:DnsQueryLifecycleObserver An observer for the new query which we may issue.

public DnsQueryLifecycleObserver queryCNAMEd(DnsQuestion cnameQuestion)

The query returned a CNAME which we may attempt to follow with a new query.

Note that multiple queries may be encountering a CNAME. For example a if both DnsRecordType#AAAA and DnsRecordType#A are supported we may query for both.

Parameters

cnameQuestion:DnsQuestion: the question we would use if we issue a new query.

Returns:DnsQueryLifecycleObserver

An observer for the new query which we may issue.

queryFailed	back to summary
public void queryFailed(Throwable cause) The following criteria are possible: IO Error Server responded with an invalid DNS response Server responded with a valid DNS response, but it didn't progress the resolution Parameters cause:Throwable The cause which for the failure.

queryFailed

back to summary

public void queryFailed(Throwable cause)

The following criteria are possible:

IO Error
Server responded with an invalid DNS response
Server responded with a valid DNS response, but it didn't progress the resolution

Parameters

cause:Throwable: The cause which for the failure.

queryNoAnswer back to summary

queryNoAnswer	back to summary
public DnsQueryLifecycleObserver queryNoAnswer(DnsResponseCode code) The response to the query didn't provide the expected response code, but it didn't return `DnsResponseCode#NXDOMAIN` so we may try to query again. Parameters code:DnsResponseCode the unexpected response code. Returns:DnsQueryLifecycleObserver An observer for the new query which we may issue.

public DnsQueryLifecycleObserver queryNoAnswer(DnsResponseCode code)

The response to the query didn't provide the expected response code, but it didn't return DnsResponseCode#NXDOMAIN so we may try to query again.

Parameters

code:DnsResponseCode: the unexpected response code.

Returns:DnsQueryLifecycleObserver

An observer for the new query which we may issue.

queryRedirected	back to summary
public DnsQueryLifecycleObserver queryRedirected(List<InetSocketAddress> nameServers) The query has been redirected to another list of DNS servers. Parameters nameServers:List<InetSocketAddress> The name servers the query has been redirected to. Returns:DnsQueryLifecycleObserver An observer for the new query which we may issue.

queryRedirected

back to summary

public DnsQueryLifecycleObserver queryRedirected(List<InetSocketAddress> nameServers)

The query has been redirected to another list of DNS servers.

Parameters

nameServers:List<InetSocketAddress>: The name servers the query has been redirected to.

Returns:DnsQueryLifecycleObserver

An observer for the new query which we may issue.

querySucceed	back to summary
public void querySucceed() The query received the expected results.

queryWritten	back to summary
public void queryWritten(InetSocketAddress dnsServerAddress, Future<Void> future) The query has been written. Parameters dnsServerAddress:InetSocketAddress The DNS server address which the query was sent to. future:Future<Void> The future which represents the status of the write operation for the DNS query.

queryWritten

back to summary

public void queryWritten(InetSocketAddress dnsServerAddress, Future<Void> future)

The query has been written.

Parameters

dnsServerAddress:InetSocketAddress: The DNS server address which the query was sent to.
future:Future<Void>: The future which represents the status of the write operation for the DNS query.

public Interface DnsQueryLifecycleObserver

Method Summary

Method Detail