Commit Graph

4 Commits

Author SHA1 Message Date
Trustin Lee
c0079840be Improve DnsNameResolverTest.testResolveA()
Motivation:

DnsNameResolver.testResolveA() tests if the cache works as well as the usual DNS protocol test.  To ensure the result from the cache is identical to the result without cache, it compares the two Maps which contain the result of cached/uncached resolution.  The comparison of two Maps yields an expected behavior, but the output of the comparison on failure is often unreadable due to its long length.

Modifications:

Compare entry-by-entry for more comprehensible test failure output

Result:

When failure occurs, it's easier to see which domain was the cause of the problem.
2014-10-25 17:29:06 +09:00
Trustin Lee
e1787e6876 Fix another resource leak in DnsNameResolver
- Fix a bug in cache expiration task; wrong object was being released
- Added more sanity checks when caching an entry
2014-10-17 11:40:06 +09:00
Trustin Lee
c811d50d61 Fix resource leak in DnsNameResolver 2014-10-16 17:57:32 +09:00
Trustin Lee
e848066cab Name resolver API and DNS-based name resolver
Motivation:

So far, we relied on the domain name resolution mechanism provided by
JDK.  It served its purpose very well, but had the following
shortcomings:

- Domain name resolution is performed in a blocking manner.
  This becomes a problem when a user has to connect to thousands of
  different hosts. e.g. web crawlers
- It is impossible to employ an alternative cache/retry policy.
  e.g. lower/upper bound in TTL, round-robin
- It is impossible to employ an alternative name resolution mechanism.
  e.g. Zookeeper-based name resolver

Modification:

- Add the resolver API in the new module: netty-resolver
- Implement the DNS-based resolver: netty-resolver-dns
  .. which uses netty-codec-dns
- Make ChannelFactory reusable because it's now used by
  io.netty.bootstrap, io.netty.resolver.dns, and potentially by other
  modules in the future
  - Move ChannelFactory from io.netty.bootstrap to io.netty.channel
  - Deprecate the old ChannelFactory
  - Add ReflectiveChannelFactory

Result:

It is trivial to resolve a large number of domain names asynchronously.
2014-10-16 17:05:20 +09:00