flink-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "ASF GitHub Bot (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (FLINK-8240) Create unified interfaces to configure and instatiate TableSources
Date Thu, 25 Jan 2018 15:00:00 GMT

    [ https://issues.apache.org/jira/browse/FLINK-8240?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16339331#comment-16339331

ASF GitHub Bot commented on FLINK-8240:

Github user twalthr commented on a diff in the pull request:

    --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/table/sources/TableSourceFactory.scala
    @@ -0,0 +1,53 @@
    + * Licensed to the Apache Software Foundation (ASF) under one
    + * or more contributor license agreements.  See the NOTICE file
    + * distributed with this work for additional information
    + * regarding copyright ownership.  The ASF licenses this file
    + * to you under the Apache License, Version 2.0 (the
    + * "License"); you may not use this file except in compliance
    + * with the License.  You may obtain a copy of the License at
    + *
    + *     http://www.apache.org/licenses/LICENSE-2.0
    + *
    + * Unless required by applicable law or agreed to in writing, software
    + * distributed under the License is distributed on an "AS IS" BASIS,
    + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    + * See the License for the specific language governing permissions and
    + * limitations under the License.
    + */
    +package org.apache.flink.table.sources
    +import java.util
    +  * A factory to create a [[TableSource]]. This factory is used with Java's Service Provider
    +  * Interfaces (SPI) for discovering. A factory is called with a set of normalized properties
    +  * describe the desired table source. The factory allows for matching to the given set
    +  * properties and creating a configured [[TableSource]] accordingly.
    +  *
    +  * Classes that implement this interface need to be added to the
    +  * "META_INF/services/org.apache.flink.table.sources.TableSourceFactory' file of a JAR
file in
    --- End diff --
    No, any JAR file can be used. We use similar functionality for the Flink file systems.
For example, we simply need to add a file to 
     `META_INF/services/org.apache.flink.table.sources.TableSourceFactory` into the Kafka
connector jar. The Java Service Provider Interfaces do the rest for us.

> Create unified interfaces to configure and instatiate TableSources
> ------------------------------------------------------------------
>                 Key: FLINK-8240
>                 URL: https://issues.apache.org/jira/browse/FLINK-8240
>             Project: Flink
>          Issue Type: New Feature
>          Components: Table API &amp; SQL
>            Reporter: Timo Walther
>            Assignee: Timo Walther
>            Priority: Major
> At the moment every table source has different ways for configuration and instantiation.
Some table source are tailored to a specific encoding (e.g., {{KafkaAvroTableSource}}, {{KafkaJsonTableSource}})
or only support one encoding for reading (e.g., {{CsvTableSource}}). Each of them might implement
a builder or support table source converters for external catalogs.
> The table sources should have a unified interface for discovery, defining common properties,
and instantiation. The {{TableSourceConverters}} provide a similar functionality but use an
external catalog. We might generialize this interface.
> In general a table source declaration depends on the following parts:
> {code}
> - Source
>   - Type (e.g. Kafka, Custom)
>   - Properties (e.g. topic, connection info)
> - Encoding
>   - Type (e.g. Avro, JSON, CSV)
>   - Schema (e.g. Avro class, JSON field names/types)
> - Rowtime descriptor/Proctime
>   - Watermark strategy and Watermark properties
>   - Time attribute info
> - Bucketization
> {code}
> This issue needs a design document before implementation. Any discussion is very welcome.

This message was sent by Atlassian JIRA

View raw message