Hi Samrat, Thanks a lot for driving the new catalog, and sorry for jumping into the discussion late.
As Flink SQL is becoming the first-class citizen of the Flink API, we are planning to push Catalog to become the first-class citizen of the connector instead of Source & Sink. For Flink SQL users, using Catalog is as natural and user-friendly as working with databases, rather than having to define DDL and schemas over and over again. This is also how Trino/Presto does. Regarding the repo for the Glue catalog, I think we can add it to flink-connector-aws. We don't need separate repos for Catalogs because Catalog is a kind of connector (others are sources & sinks). For example, MySqlCatalog[1] and PostgresCatalog[2] are in flink-connector-jdbc, and HiveCatalog is in flink-connector-hive. This can reduce repository maintenance, and I think maybe some common AWS utils can be shared there. cc @Danny Cranmer <dannycran...@apache.org> what do you think about this? Besides, I have a question about Glue Namespace. Could you share the documentation of the Glue Namespaces? (Sorry, I didn't find it.) According to the "Flink Glue Metaspace Mapping" section, if there is a database "mydb" under namespace "ns1", is that mean the database name in Flink is "ns1.mydb"? Best, Jark [1]: https://github.com/apache/flink/blob/master/flink-connectors/flink-connector-jdbc/src/main/java/org/apache/flink/connector/jdbc/catalog/MySqlCatalog.java [2]: https://github.com/apache/flink/blob/master/flink-connectors/flink-connector-jdbc/src/main/java/org/apache/flink/connector/jdbc/catalog/PostgresCatalog.java On Fri, 9 Dec 2022 at 08:51, Dong Lin <lindon...@gmail.com> wrote: > Hi Samrat, > > Sorry for the late reply. Yeah I am referring to creating a similar > external repo such as flink-catalog-glue. flink-connector-aws is already > named with `connector` so it seems a bit weird to put a catalog there. > > Thanks! > Dong > > On Wed, Dec 7, 2022 at 1:04 PM Samrat Deb <decordea...@gmail.com> wrote: > > > Hi Dong Lin, > > > > Since this is the first proposal for adding a vendor-specific catalog > > > library in Flink, I think maybe we should also externalize those > catalog > > > libraries similar to how we are externalizing connector libraries. It > is > > > likely that we might want to add catalogs for other vectors in the > > future. > > > Externalizing those catalogs can make Flink development more scalable > in > > > the long term. > > > > Initially i mis-interpretted externalising the catalogs, There already > > exists an externalised connector for aws [1]. > > Are you referring to creating a similar external repo for catalogs or > will > > it be better to add it in flink-connector-aws[1] ? > > > > [1] https://github.com/apache/flink-connector-aws > > > > Samrat > > > > On Tue, Dec 6, 2022 at 6:52 PM Samrat Deb <decordea...@gmail.com> wrote: > > > > > Hi Dong Lin, > > > > > > Aws Glue Data catalog is vendor specific and in future we will get such > > > type of implementation from different providers. We should > > > definitely externalize these catalog libraries similar to flink > > connectors. > > > I am thinking of creating > > > flink-catalog similar to flink-connector under the root (flink). glue > > > catalog can be one of modules under the flink-catalog . Please suggest > if > > > there is a better structure we can create for catalogs. > > > > > > > > > It is mentioned in the FLIP that there will be two types of > SdkHttpClient > > >> supported based on the catalog option http-client.type. Is > > >> http-client.type > > >> a public config for the GlueCatalog? If yes, can we add this config to > > the > > >> "Configurations" section and explain how users should choose the > client > > >> type? > > > > > > > > > yes http-client.type is public config for the GlueCatalog. By default > > > client-type will be `urlconnection` , if user don't specify any > > connection > > > type. > > > I have updated the FLIP-277[1] #configuration section with all the > > configs > > > . Please review it again . > > > > > > [1] > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-277%3A+Native+GlueCatalog+Support+in+Flink > > > > > > Samrat > > > > > > On Tue, Dec 6, 2022 at 5:50 PM Samrat Deb <decordea...@gmail.com> > wrote: > > > > > >> Hi Yuxia, > > >> > > >> Thank you for reviewing the flip and putting forward your observations > > >> and comments. > > >> > > >> 1: I noticed there's a YAML part in the section of "Using the > Catalog", > > >>> what do you mean by that? Do you mean how to use glue catalog in sql > > >>> client? If so, just for your information, it's not supported to use > > yaml > > >>> envrioment file in sql client[2]. > > >> > > >> > > >> Thank you for attaching the jira ticket [1] . I missed the changes. > > >> There is a provision to register catalog directly through factory > > resources > > >> . > > >> - GenericInMemoryCatalog is defined through > > >> > > > `flink/flink-table/flink-table-api-java/src/main/resources/META-INF/services/org.apache.flink.table.factories.Factory` > > >> - HiveCatalog is defined through > > >> path > > > `flink-connectors/flink-connector-hive/src/main/resources/META-INF/services/org.apache.flink.table.factories.Factory` > > >> Similarly on the vendor specific module for Aws Glue we can define it. > > >> > > >> 2: Seems there's a typo in "Design#views" part, it contains > "listTables" > > >>> which I think shouldn't be contained. > > >> > > >> > > >> oh yes 😅 ! fixed it now thanks for pointing it out. > > >> > > >> > > >> Also, I'm curious about how to list views using Glue API. Is there an > > >>> on-hand api to list views directly or we need to list the tables and > > then > > >>> filter the views using the table-kind? > > >> > > >> > > >> yes there is no in-hand api for list views directly , we need to list > > all > > >> tables and then filter the views based on attribute tableKind which > is a > > >> part of table object in api response. > > >> > > >> > > >> 3: In "Flink Glue DataType Mapping" part, CharType is mapped to > String. > > >>> It seems the char's size will lose, is it possible to have a better > > mapping > > >>> which won't loss the size of char type? > > >> > > >> > > >> Thanks for pointing this out ! I have updated the flip with the > correct > > >> type. Initilially i mapped chartype , varchar type to string but > > updated it > > >> to directly map to the same type . > > >> > > >> > > >> > > >>> 4: About the "Flink CatalogFunction mapping with Glue Function" part, > > >>> how do we map the function language in Flink's CatalogFunction. > > >> > > >> > > >> Glue Api (UserDefinedFunctionInput) doesn't support specific attribute > > >> for function language. Here is how aws hive compatible metastore is > > mapping > > >> hive function to glue function[2]. We will append a prefix of Language > > in > > >> the function name itself indicating the language. I see this has been > > >> already done for the Hive Catalog [3]. We are thinking of implementing > > it > > >> in the same way. > > >> > > >> [1] https://issues.apache.org/jira/browse/FLINK-22540 > > >> [2] > > >> > > > https://github.com/awslabs/aws-glue-data-catalog-client-for-apache-hive-metastore/blob/master/aws-glue-datacatalog-client-common/src/main/java/com/amazonaws/glue/catalog/converters/GlueInputConverter.java#L83 > > >> [3] > > >> > > > https://github.com/apache/flink/blob/master/flink-connectors/flink-connector-hive/src/main/java/org/apache/flink/table/catalog/hive/HiveCatalog.java#L1415 > > >> > > >> Samrat > > >> > > >> On Mon, Dec 5, 2022 at 4:33 PM Dong Lin <lindon...@gmail.com> wrote: > > >> > > >>> Hi Samrat, > > >>> > > >>> Thanks for the FLIP! > > >>> > > >>> Since this is the first proposal for adding a vendor-specific catalog > > >>> library in Flink, I think maybe we should also externalize those > > catalog > > >>> libraries similar to how we are externalizing connector libraries. It > > is > > >>> likely that we might want to add catalogs for other vectors in the > > >>> future. > > >>> Externalizing those catalogs can make Flink development more scalable > > in > > >>> the long term. > > >>> > > >>> It is mentioned in the FLIP that there will be two types of > > SdkHttpClient > > >>> supported based on the catalog option http-client.type. Is > > >>> http-client.type > > >>> a public config for the GlueCatalog? If yes, can we add this config > to > > >>> the > > >>> "Configurations" section and explain how users should choose the > client > > >>> type? > > >>> > > >>> Regards, > > >>> Dong > > >>> > > >>> > > >>> On Sat, Dec 3, 2022 at 12:31 PM Samrat Deb <decordea...@gmail.com> > > >>> wrote: > > >>> > > >>> > Hi everyone, > > >>> > > > >>> > I would like to open a discussion[1] on providing GlueCatalog > support > > >>> > in Flink. > > >>> > Currently, Flink offers 3 major types of catalog[2]. Out of which > > only > > >>> > HiveCatalog is a persistent catalog backed by Hive Metastore. We > > would > > >>> like > > >>> > to introduce GlueCatalog in Flink offering another option for users > > >>> which > > >>> > will be persistent in nature. Aws Glue data catalog is a > centralized > > >>> data > > >>> > catalog in AWS cloud that provides integrations with many different > > >>> > connectors[3]. Flink GlueCatalog can use the features provided by > > glue > > >>> and > > >>> > create strong integration with other services in the cloud. > > >>> > > > >>> > [1] > > >>> > > > >>> > > > >>> > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-277%3A+Native+GlueCatalog+Support+in+Flink > > >>> > > > >>> > [2] > > >>> > > > >>> > > > >>> > > > https://nightlies.apache.org/flink/flink-docs-master/docs/dev/table/catalogs/ > > >>> > > > >>> > [3] > > >>> > > > >>> > > > >>> > > > https://docs.aws.amazon.com/glue/latest/dg/components-overview.html#data-catalog-intro > > >>> > > > >>> > [4] https://issues.apache.org/jira/browse/FLINK-29549 > > >>> > > > >>> > Bests > > >>> > Samrat > > >>> > > > >>> > > >> > > >
