Motivation:
a416b79 introduced a check for null or empty host name to be compatible with the JDK resolution. However the doResolve(String, Promise) method, and if the doResolve(String, DnsRecord[], Promise, DnsCache) method was overridden the empty/null hostname would not be correctly resolved.
Modifications:
- Move the empty/null host name check into the lowest level doResolve method in DnsNameResolver
- Remove the duplicate logic in InetNameResolver.java which can be bypassed anyways
Result:
By default (unless behavior is overridden) DnsNameResolver resolves null/empty host names to local host just like the JDK.
Motivation:
When an empty hostname is used in DnsNameResolver.resolve*(...) it will never notify the future / promise. The root cause is that we not correctly guard against errors of IDN.toASCII(...) which will throw an IllegalArgumentException when it can not parse its input. That said we should also handle an empty hostname the same way as the JDK does and just use "localhost" when this happens.
Modifications:
- If the try to resolve an empty hostname we use localhost
- Correctly guard against errors raised by IDN.toASCII(...) so we will always noify the future / promise
- Add unit test.
Result:
DnsNameResolver.resolve*(...) will always notify the future.
Motivation:
Windows 7 hosts file is empty by default (at least on my machine? see
http://serverfault.com/questions/4689/windows-7-localhost-name-resolution-is-handled-within-dns-itself-why
for details and reasoning.
the test relies on the file containing an entry for localhost.
Modifications:
refactor class code to 1st normalize the input host name and then look it up, change the test to verify
that hostnames are normalized in a case-insensitive way before being looked up (which was the intent
of the original test)
Result:
test should pass on vanilla windows 7 (and any other machine with no
localhost in the hosts file). no effect anywhere else or on actual netty
code.
Signed-off-by: radai-rosenblatt <radai.rosenblatt@gmail.com>
Motivation:
InetSocketAddressResolver.close() must call close() on the wrapped NameResolver.
Modifications:
Correctly call close() on wrapped NameResolver and added test.
Result:
close() is correctly propergated to the wrapped resolver.
Motivation:
Resolving hosts via the /etc/hosts file should be case-insensitive, e.g. localhost and LOCALHOST refer to the same host, this is the same that is applied to dns queries.
Modifications:
Store hosts Map with lowercase keys, lookup the keys as lowercase
Add to unit test for the hosts file parser to use an UPPERCASE file entry
Add unit test for DefaultHostsFileEntriesResolver to resolve both localhost and LOCALHOST
Result:
host resolution for local hosts file should match the rules applied to "getent hosts" or "ping"
Motivation:
On contrary to `DefaultNameResolver`, `DnsNameResolver` doesn't currently honor hosts file.
Modifications:
* Introduce `HostsFileParser` that parses `/etc/hosts` or `C:\Windows\system32\drivers\etc\hosts` depending on the platform
* Introduce `HostsFileEntriesResolver` that uses the former to resolve host names
* Make `DnsNameResolver` check his `HostsFileEntriesResolver` prior to trying to resolve names against the DNS server
* Introduce `DnsNameResolverBuilder` so we now have a builder for `DnsNameResolver`s
* Additionally introduce a `CompositeNameResolver` that takes several `NameResolver`s and tries to resolve names by delegating sequentially
* Change `DnsNameResolver.asAddressResolver` to return a composite and honor hosts file
Result:
Hosts file support when using `DnsNameResolver`.
Consistent behavior with JDK implementation.
