This could be a good fit, I'll try to dig into it and see if it can be
adapted to a REST service.
The only strange thing I see is that the key of the local cache is per
block of keys..am I wrong?
Shouldn't it cycle over the list of passed keys?
Right now it's the following:
Cache<Row, List<Row>> cache;
public void eval(Object... keys) {
Row keyRow = Row.of(keys);
if (cache != null) {
List<Row> cachedRows = cache.getIfPresent(keyRow);
if (cachedRows != null) {
for (Row cachedRow : cachedRows) {
collect(cachedRow);
}
return;
}
}
...
while I'd use the following (also for JDBC):
Cache<Row, List<Row>> cache;
public void eval(Object... keys) {
Row keyRow = Row.of(keys);
if (cache != null) {
List<Row> cachedRows = cache.getIfPresent(keyRow);
if (cachedRows != null) {
for (Row cachedRow : cachedRows) {
collect(cachedRow);
}
return;
}
}
...
public void eval(Object... keys) {
for (Object kkk : keys) {
Row keyRow = Row.of(kkk);
if (cache != null) {
List<Row> cachedRows = cache.getIfPresent(keyRow);
if (cachedRows != null) {
for (Row cachedRow : cachedRows) {
collect(cachedRow);
}
return;
}
}
}
...
Am I missing something?
On Fri, Jun 28, 2019 at 4:18 PM JingsongLee <lzljs3620...@aliyun.com> wrote:
> Hi Flavio:
>
> I just implement a JDBCLookupFunction[1]. You can use it as table
> function[2]. Or use
> blink temporal table join[3] (Need blink planner support).
> I add a google guava cache in JDBCLookupFunction with configurable
> cacheMaxSize
> (avoid memory OOM) and cacheExpireMs(For the fresh of lookup table).
> Is that you want?
>
> [1]
> https://github.com/JingsongLi/flink/blob/cc80999279b38627b37fa7550fb6610eee450d86/flink-connectors/flink-jdbc/src/main/java/org/apache/flink/api/java/io/jdbc/JDBCLookupFunction.java
> [2]
> https://github.com/JingsongLi/flink/blob/cc80999279b38627b37fa7550fb6610eee450d86/flink-connectors/flink-jdbc/src/test/java/org/apache/flink/api/java/io/jdbc/JDBCLookupFunctionITCase.java#L143
> [3]
> https://github.com/apache/flink/blob/master/flink-table/flink-table-planner-blink/src/test/scala/org/apache/flink/table/runtime/stream/sql/LookupJoinITCase.scala#L75
>
> Best, JingsongLee
>
> ------------------------------------------------------------------
> From:Flavio Pompermaier <pomperma...@okkam.it>
> Send Time:2019年6月28日(星期五) 21:04
> To:user <user@flink.apache.org>
> Subject:LookupableTableSource question
>
> Hi to all,
> I have a use case where I'd like to enrich a stream using a rarely updated
> lookup table.
> Basically, I'd like to be able to set a refresh policy that is triggered
> either when a key was not found (a new key has probably been added in the
> mean time) or a configurable refresh-period has elapsed.
>
> Is there any suggested solution to this? The LookupableTableSource looks
> very similar to what I'd like to achieve but I can't find a real-world
> example using it and it lacks of such 2 requirements (key-values are not
> refreshed after a configurable timeout and a KeyNotFound callback cannot be
> handled).
>
> Any help is appreciated,
> Flavio
>
>
>
