Thanks Robert, this looks great
+1 (non-binding)
On Thu, May 17, 2018 at 5:35 PM, Colin McCabe <cmcc...@apache.org> wrote:
> Thanks, Robert!
>
> +1 (non-binding)
>
> Colin
>
>
> On Thu, May 17, 2018, at 14:15, Robert Yokota wrote:
> > Hi Colin,
> >
> > I've changed the KIP to have a composite object returned from get().
> It's
> > probably the most straightforward option. Please let me know if you have
> > any other concerns.
> >
> > Thanks,
> > Robert
> >
> > On Thu, May 17, 2018 at 11:44 AM, Robert Yokota <rayok...@gmail.com>
> wrote:
> >
> > >
> > >
> > > Hi Colin,
> > >
> > > My last response was not that clear, so let me back up and explain a
> bit
> > > more.
> > >
> > > Some secret managers, such as Vault (and maybe Keywhiz) have the
> notion of
> > > a lease duration or a TTL for a path. Every path can have a different
> > > TTL. This is period after which the value of the keys at the given
> path
> > > may be invalid. It can be used to indicate a rotation will be done.
> In
> > > the cause of the Vault integration with AWS, Vault will actually
> delete the
> > > secrets from AWS at the moment the TTL expires. A TTL could be used by
> > > other ConfigProviders, such as a FileConfigProvider, to indicate that
> all
> > > the secrets at a given path (file), will be rotated on a regular basis.
> > >
> > > I would like to expose the TTL in the APIs somewhere. The TTL can be
> made
> > > available at the time get() is called. Connect already has a built in
> > > ScheduledExecutor, so Connect can just use the TTL to schedule a
> Connector
> > > restart. Originally, I had exposed the TTL in a ConfigContext
> interface
> > > passed to the get() method. To reduce the number of APIs, I placed it
> on
> > > the onChange() method. This means at the time of get(), onChange()
> would
> > > be called with a TTL. The Connector's implementation of the callback
> would
> > > use onChange() with the TTL to schedule a restart.
> > >
> > > If you think this is overloading onChange() too much, I could add the
> > > ConfigContext back to get():
> > >
> > >
> > > Map<String, String> get(ConfigContext ctx, String path);
> > >
> > > public interface ConfigContext {
> > >
> > > void willExpire(String path, long ttl);
> > >
> > > }
> > >
> > >
> > >
> > > or I could separate out the TTL method in the callback:
> > >
> > >
> > > public interface ConfigChangeCallback {
> > >
> > > void willExpire(String path, long ttl);
> > >
> > > void onChange(String path, Map<String, String> values);
> > > }
> > >
> > >
> > >
> > > Or we could return a composite object from get():
> > >
> > > ConfigData get(String path);
> > >
> > > public class ConfigData {
> > >
> > > Map<String, String> data;
> > > long ttl;
> > >
> > > }
> > >
> > >
> > > Do you have a preference Colin?
> > >
> > > Thanks,
> > > Robert
> > >
> > >
> > > On Thu, May 17, 2018 at 9:27 AM, Colin McCabe <cmcc...@apache.org>
> wrote:
> > >
> > >> Hi Robert,
> > >>
> > >> Hmm. I thought that if you're using ConfigChangeCallback, you are
> > >> relying on the ConfigProvider to make a callback to you when the
> > >> configuration has changed. So isn't that always the "push model"
> (where
> > >> the ConfigProvider pushes changes to Connect). If you want the "pull
> > >> model" where you initiate updates, you can simply call
> ConfigProvider#get
> > >> directly, right?
> > >>
> > >> The actual implementation of ConfigProvider subclasses will depend on
> the
> > >> type of configuration storage mechanism on the backend. In the case
> of
> > >> Vault, it sounds like we need to have something like a
> ScheduledExecutor
> > >> which re-fetches keys after a certain amount of time.
> > >>
> > >> As an aside, what does a "lease duration" mean for a configuration
> key?
> > >> Does that mean Vault will reject changes to the configuration key if
> I try
> > >> to make them within the lease duration? Or is this like a period
> after
> > >> which a password is automatically rotated?
> > >>
> > >> On Wed, May 16, 2018, at 22:25, Robert Yokota wrote:
> > >> > Hi Colin,
> > >> >
> > >> > > With regard to delayMs, can’t we just restart the
> > >> > > Connector when the keys are actually changed?
> > >> >
> > >> > Currently the VaultConfigProvider does not find out when values for
> keys
> > >> > have changed. You could do this with a poll model (with a
> > >> > background thread in the ConfigProvider), but since for each
> key-value
> > >> > pair, Vault provides a lease duration stating exactly when a value
> for a
> > >> > key will change in the future, this is an alternative model of just
> > >> passing
> > >> > the lease duration to the client (in this case the Connector), to
> allow
> > >> it
> > >> > to determine what to do (such as schedule a restart). This may
> allow
> > >> one
> > >> > to avoid the complexity of figuring out a proper poll interval (with
> > >> lease
> > >> > durations of varying periods), or worrying about putting too much
> load
> > >> on
> > >> > the secrets manager by polling too often.
> > >>
> > >> Those things are still concerns if the Connector is polling, right?
> > >> Perhaps the connector poll too often and puts too much load on
> Vault. And
> > >> so forth. It seems like this problem needs to be solved either way
> (and
> > >> probably can be solved with reasonable default minimum fetch
> intervals).
> > >>
> > >> best,
> > >> Colin
> > >>
> > >>
> > >> > In other words, by adding this
> > >> > one additional parameter, a ConfigProvider can provide both push and
> > >> pull
> > >> > models to clients, perhaps with an additional configuration
> parameter to
> > >> > the ConfigProvider to determine which model (push or poll) to use.
> > >> >
> > >> > Thanks,
> > >> > Robert
> > >> >
> > >> > On Wed, May 16, 2018 at 9:56 PM, Colin McCabe <cmcc...@apache.org>
> > >> wrote:
> > >> >
> > >> > > Thanks, Robert. With regard to delayMs, can’t we just restart the
> > >> > > Connector when the keys are actually changed? Or is the concern
> that
> > >> > > this would lengthen the effective key rotation time? Can’t the
> user
> > >> > > just configure a slightly shorter key rotation time to counteract
> > >> > > this concern?
> > >> > > Regards,
> > >> > > Colin
> > >> > >
> > >> > > On Wed, May 16, 2018, at 19:13, Robert Yokota wrote:
> > >> > > > Hi Colin,
> > >> > > >
> > >> > > > Good questions.
> > >> > > >
> > >> > > >
> > >> > > > > As a clarification about the indirections, what if I have the
> > >> > > > > connect> configuration key foo set up as ${vault:bar}, and in
> > >> Vault,
> > >> > > > have the bar> key set to ${file:baz}?
> > >> > > > > Does connect get foo as the contents of the baz file? I would
> > >> > > > > argue that> it should not (and in general, we shouldn't allow
> > >> > > ConfigProviders to
> > >> > > > indirect to other
> > >> > > > > ConfigProviders) but I don't think it's spelled out right now.
> > >> > > >
> > >> > > > I've added a clarification to the KIP that further indirections
> are
> > >> > > > not> performed even if the values returned from ConfigProviders
> > >> have the
> > >> > > > variable syntax.
> > >> > > >
> > >> > > >
> > >> > > > > What's the behavior when a config key is not found in Vault
> > >> > > > > (or other> ConfigProvider)? Does the variable get replaced
> with
> > >> the
> > >> > > empty
> > >> > > > string, or> with the literal ${vault:whatever} string?
> > >> > > >
> > >> > > > It would remain unresolved and still be of the form
> > >> > > > ${provider:key}. I've> added a clarification to the KIP.
> > >> > > >
> > >> > > >
> > >> > > > > Do we really need "${provider:[path:]key}", or can it just be
> > >> > > > ${provider:key}?
> > >> > > >
> > >> > > > The path is a separate parameter in the APIs, so I think it's
> > >> > > > important to> explicitly delineate it in the variable syntax.
> For
> > >> > > example, I
> > >> > > > currently> have a working VaultConfigProvider prototype and the
> > >> syntax
> > >> > > for a
> > >> > > > Vault key> reference looks like
> > >> > > >
> > >> > > > db_password=${vault:secret/staging:mysql_password}
> > >> > > >
> > >> > > > I think it's important to standardize how to separate the path
> > >> > > > from the key> rather than leave it to each ConfigProvider to
> > >> determine a
> > >> > > possibly
> > >> > > > different way. This will also make it easier to move secrets
> from
> > >> one>
> > >> > > ConfigProvider to another should one choose to do so.
> > >> > > >
> > >> > > >
> > >> > > > > Do we really need delayMs?
> > >> > > >
> > >> > > > One of the goals of this KIP is to allow for secrets rotation
> > >> without>
> > >> > > having to modify existing connectors. In the case of the
> > >> > > > VaultConfigProvider, it knows the lease durations and will be
> able
> > >> to>
> > >> > > schedule a restart of the Connector using an API in the Herder.
> The
> > >> > > > delayMs will simply be passed to the
> Herder.restartConnector(long
> > >> > > > delayMs,> String connName, Callback cb) method here:
> > >> > > >
> > >> > > > https://github.com/rayokota/kafka/blob/secrets-in-connect-
> > >> > > configs/connect/runtime/src/main/java/org/apache/kafka/
> > >> > > connect/runtime/Herder.java#L170>
> > >> > > >
> > >> > > > Best,
> > >> > > > Robert
> > >> > > >
> > >> > > >
> > >> > > >
> > >> > > > On Wed, May 16, 2018 at 6:16 PM, Colin McCabe
> > >> > > > <cmcc...@apache.org> wrote:>
> > >> > > > > Thanks, Robert. Looks good overall.
> > >> > > > >
> > >> > > > > As a clarification about the indirections, what if I have the
> > >> > > > > connect> > configuration key foo set up as ${vault:bar}, and
> in
> > >> Vault,
> > >> > > have
> > >> > > > > the bar> > key set to ${file:baz}? Does connect get foo as
> the
> > >> > > contents of
> > >> > > > > the baz> > file? I would argue that it should not (and in
> > >> general, we
> > >> > > > > shouldn't allow> > ConfigProviders to indirect to other
> > >> > > ConfigProviders) but I
> > >> > > > > don't think> > it's spelled out right now.
> > >> > > > >
> > >> > > > > What's the behavior when a config key is not found in Vault
> > >> > > > > (or other> > ConfigProvider)? Does the variable get replaced
> > >> with the
> > >> > > empty
> > >> > > > > string, or> > with the literal ${vault:whatever} string?
> > >> > > > >
> > >> > > > > Do we really need "${provider:[path:]key}", or can it just be
> > >> > > > > ${provider:key}? It seems like the path can be rolled up
> into the
> > >> > > > > key. So> > if you want to put your connect keys under
> > >> > > my.connect.path, you
> > >> > > > > ask for> > ${vault:my.connect.path.jdbc.config}, etc.
> > >> > > > >
> > >> > > > > > // A delayMs of 0 indicates an immediate change; a
> positive
> > >> > > > > > delayMs> > indicates
> > >> > > > > > // that a future change is anticipated (such as a lease
> > >> > > > > > duration)> > > void onChange(String path, Map<String,
> > >> String>
> > >> > > values, int
> > >> > > > > > delayMs);> >
> > >> > > > > Do we really need delayMs? It seems like if you get a
> callback
> > >> with>
> > >> > > > delayMs set, you don't know what the new values will be, only
> > >> > > > > that an> > update is coming, but not yet here.
> > >> > > > >
> > >> > > > > best,
> > >> > > > > Colin
> > >> > > > >
> > >> > > > >
> > >> > > > > On Wed, May 16, 2018, at 17:05, Robert Yokota wrote:
> > >> > > > > > Hello everyone,
> > >> > > > > >
> > >> > > > > > After a good round of discussions with excellent feedback
> and no
> > >> > > > > > major> > > objections, I would like to start a vote on
> KIP-297
> > >> to
> > >> > > externalize> > secrets
> > >> > > > > > from Kafka Connect configurations. My thanks in advance!
> > >> > > > > >
> > >> > > > > > KIP: <
> > >> > > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> > >> > > > > 297%3A+Externalizing+Secrets+for+Connect+Configurations
> > >> > > > > > >
> > >> > > > > >
> > >> > > > > > JIRA: <https://issues.apache.org/jira/browse/KAFKA-6886>
> > >> > > > > >
> > >> > > > > > Discussion thread: <
> > >> > > > > > https://www.mail-archive.com/dev@kafka.apache.org/msg87638.
> html
> > >> >
> > >> > > > > >
> > >> > > > > > Best,
> > >> > > > > > Robert
> > >> > > > >
> > >> > >
> > >> > >
> > >>
> > >
> > >
>
