On Thu, Jan 24, 2019, at 11:25, TEJAL ADSUL wrote: > > > On 2019/01/24 17:26:02, Andy Coates <a...@confluent.io> wrote: > > I'm wondering why we're rejected changing AbstractConfig to automatically > > resolve the variables? > > > > > 1. Change AbstractConfig to *automatically* resolve variables of the form > > specified in KIP-297. This was rejected because it would change the > > behavior of existing code and might cause unexpected effects. > > > > Doing so seems to me to have two very large benefits: > > > > 1. It allows the config providers to be defined within the same file as the > > config that uses the providers, e.g. > > > > config.providers=file,vault > > <https://cwiki.apache.org/confluence/display/KAFKA/config.providers=file,vault> > > config.providers.file. > > <https://cwiki.apache.org/confluence/display/KAFKA/config.providers.file.> > > class=org.apache.kafka.connect.configs.FileConfigProvider > > <https://cwiki.apache.org/confluence/display/KAFKA/org.apache.kafka.connect.configs.FileConfigProvider> > > config.providers.file.param.path= > > <https://cwiki.apache.org/confluence/display/KAFKA/config.providers.file.other.prop=another> > > /mnt/secrets/passwords > > > > foo.baz=/usr/temp/ > > <https://cwiki.apache.org/confluence/display/KAFKA/foo.baz=/usr/temp/> > > foo.bar=$ <https://cwiki.apache.org/confluence/display/KAFKA/foo.bar=$> > > {file:/path/to/variables.properties:foo.bar} > > > > Is this possible with what's currently being proposed? i.e could you load > > the file and pass the map first to `loadConfigProviders` and then again to > > the constructor? > > > > 2. It allows _all_ existing clients of the class, e.g. those in Apache > > Kafka or in applications written by other people that use the class, to get > > this functionality for free, i.e. without any code changes. (I realize > > this is probably where the 'unexpected effects' comes from). > > > > I'm assuming the unexpected side effects come about if an existing > > properties file already contains compatible config.providers > > <https://cwiki.apache.org/confluence/display/KAFKA/config.providers=file,vault> > > entries _and_ has other properties in the form ${xx:yy} or ${xx:yy:zz}. > > While possible, these seems fairly unlikely unless for random client > > property files. So I'm assuming there's a specific instance where we think > > this is likely? Something to do with Connect config maybe? > > > > Personally, I think we should do our best to make this work seamlessly / > > transparently, because we're likely going to have this functionality for a > > long time. > > > > Andy > > > > > > > > > > On Tue, 22 Jan 2019 at 17:38, te...@confluent.io <te...@confluent.io> wrote: > > > > > Hi all, > > > > > > We would like to start vote on KIP-421 to to enhance the AbstractConfig > > > base class to support replacing variables in configurations just prior to > > > parsing and validation. > > > > > > Link for the KIP: > > > > > > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-421%3A+Support+resolving+externalized+secrets+in+AbstractConfig > > > > > > > > > Thanks, > > > Tejal > > >
Hi, I think Andy and Rajini bring up a good point. If this change is limited to just Connect, then it's not completely clear why it needs to be in AbstractConfig. On the other hand, if it applies to brokers and clients (and other things), then we should figure out how that integration will look. > > Hi Andy, > > So wanted to make sure that we come up with a simple approach with no > side effects or additional changes to any components. The rejected > approach would require a change in Connect's behavior and we dint want > to make that for this approach. It seems like it should be possible to keep Connect's behavior the same as it is now, but add automatic external configuration lookup to the Kafka broker. In order to do this, we could have an additional parameter that was set by the broker but not by Connect. One candidate is we could have a Java parameter which describes which config key to look at to find the config providers. Then the broker could set this, but connect could leave it unset. Then people using the broker could describe their config providers in the configuration file itself, and connect users could do something different if desired. best, Colin > > also regarding Point 1. yes thats exactly the expected behavior of > loadConfigProviders, we will send a file to it and it will create the > instances of the configProvider which will be consumed by the > constructor. > > Thanks, > Tejal >
