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https://issues.apache.org/jira/browse/BEAM-9008?focusedWorklogId=374650&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-374650
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ASF GitHub Bot logged work on BEAM-9008:
----------------------------------------

                Author: ASF GitHub Bot
            Created on: 20/Jan/20 16:36
            Start Date: 20/Jan/20 16:36
    Worklog Time Spent: 10m 
      Work Description: iemejia commented on pull request #10546: [BEAM-9008] 
add CassandraIO readAll method
URL: https://github.com/apache/beam/pull/10546#discussion_r365717276
 
 

 ##########
 File path: 
sdks/java/io/cassandra/src/main/java/org/apache/beam/sdk/io/cassandra/CassandraConfig.java
 ##########
 @@ -0,0 +1,60 @@
+package org.apache.beam.sdk.io.cassandra;
+
+import com.datastax.driver.core.Session;
+import com.google.auto.value.AutoValue;
+import java.io.Serializable;
+import java.util.List;
+import javax.annotation.Nullable;
+import org.apache.beam.sdk.options.ValueProvider;
+import org.apache.beam.sdk.transforms.SerializableFunction;
+
+@AutoValue
+abstract class CassandraConfig<T> implements Serializable {
+  @Nullable
+  abstract ValueProvider<List<String>> hosts();
+
+  @Nullable
+  abstract ValueProvider<String> query();
+
+  @Nullable
+  abstract ValueProvider<Integer> port();
+
+  @Nullable
+  abstract ValueProvider<String> keyspace();
+
+  @Nullable
+  abstract ValueProvider<String> table();
+
+  @Nullable
+  abstract ValueProvider<String> username();
+
+  @Nullable
+  abstract ValueProvider<String> password();
+
+  @Nullable
+  abstract ValueProvider<String> localDc();
+
+  @Nullable
+  abstract ValueProvider<String> consistencyLevel();
+
+  @Nullable
+  abstract SerializableFunction<Session, Mapper> mapperFactoryFn();
+
+  @Nullable
+  abstract Class<T> entity();
+
+  public static <T> CassandraConfig<T> Create(ValueProvider<List<String>> 
hosts,
 
 Review comment:
   lowercase c
 
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Issue Time Tracking
-------------------

    Worklog Id:     (was: 374650)
    Time Spent: 1.5h  (was: 1h 20m)

> add readAll() method to CassandraIO
> -----------------------------------
>
>                 Key: BEAM-9008
>                 URL: https://issues.apache.org/jira/browse/BEAM-9008
>             Project: Beam
>          Issue Type: New Feature
>          Components: io-java-cassandra
>    Affects Versions: 2.16.0
>            Reporter: vincent marquez
>            Assignee: vincent marquez
>            Priority: Minor
>          Time Spent: 1.5h
>  Remaining Estimate: 0h
>
> When querying a large cassandra database, it's often *much* more useful to 
> programatically generate the queries needed to to be run rather than reading 
> all partitions and attempting some filtering.  
> As an example:
> {code:java}
> public class Event { 
>    @PartitionKey(0) public UUID accountId;
>    @PartitionKey(1)public String yearMonthDay; 
>    @ClusteringKey public UUID eventId;  
>    //other data...
> }{code}
> If there is ten years worth of data, you may want to only query one year's 
> worth.  Here each token range would represent one 'token' but all events for 
> the day. 
> {code:java}
> Set<UUID> accounts = getRelevantAccounts();
> Set<String> dateRange = generateDateRange("2018-01-01", "2019-01-01");
> PCollection<TokenRange> tokens = generateTokens(accounts, dateRange); 
> {code}
>  
>  I propose an additional _readAll()_ PTransform that can take a PCollection 
> of token ranges and can return a PCollection<T> of what the query would 
> return. 
> *Question: How much code should be in common between both methods?* 
> Currently the read connector already groups all partitions into a List of 
> Token Ranges, so it would be simple to refactor the current read() based 
> method to a 'ParDo' based one and have them both share the same function.  
> Reasons against sharing code between read and readAll
>  * Not having the read based method return a BoundedSource connector would 
> mean losing the ability to know the size of the data returned
>  * Currently the CassandraReader executes all the grouped TokenRange queries 
> *asynchronously* which is (maybe?) fine when all that's happening is 
> splitting up all the partition ranges but terrible for executing potentially 
> millions of queries. 
>  Reasons _for_ sharing code would be simplified code base and that both of 
> the above issues would most likely have a negligable performance impact. 
>  
>  
>  



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