[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-06-10 Thread Everett Rush (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17132743#comment-17132743
 ] 

Everett Rush commented on SPARK-27249:
--

I checked out the code and the design. Thanks for the great effort, but this 
doesn't quite meet the need. The transformer contract can still be met with a 
transform function that returns a Dataframe. 

I would like something more like this.

 

{{@DeveloperApi}}
{{abstract class MultiColumnTransformer[T<: MultiColumnTransformer[T]]}}
{{ extends Transformer with HasOutputCol with Logging {}}


{{ def setOutputCol(value: String): T = set(outputCol, value).asInstanceOf[T]}}

{{ /** Returns the data type of the output column. */}}
{{ protected def outputDataType: DataType}}

{{ protected def *transformFunc*: Iterator[Row] => Iterator[Row]}}


{{ override def *transformSchema*(schema: StructType): StructType = {}}
{{ }}}

{{ def *transform*(dataset: DataFrame, targetSchema: StructType): DataFrame = 
{}}

{{ val targetEncoder = RowEncoder(targetSchema)}}
{{ dataset.mapPartitions(transformFunc)(targetEncoder)}}
{{ }}}

{{ override def *transform*(dataset: Dataset[_]): DataFrame = {}}
{{ val dataframe = dataset.toDF()}}
{{ val targetSchema = transformSchema(dataframe.schema, logging = true)}}
{{ transform(dataframe, targetSchema)}}
{{ }}}

{{ override def copy(extra: ParamMap): T = defaultCopy(extra)}}
{{}}}

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.1.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-06-09 Thread Everett Rush (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17129814#comment-17129814
 ] 

Everett Rush commented on SPARK-27249:
--

[~nafshartous] Hi Nick, thanks for looping me in. I just got time to look at 
this.

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.1.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-05-11 Thread Nick Afshartous (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17104661#comment-17104661
 ] 

Nick Afshartous commented on SPARK-27249:
-

[~enrush] Hi Everett, can you please chime in on the thread in the PR.  There's 
a question about whether or not the need is covered by existing API's.  

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.1.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-05-10 Thread Apache Spark (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17103917#comment-17103917
 ] 

Apache Spark commented on SPARK-27249:
--

User 'nafshartous' has created a pull request for this issue:
https://github.com/apache/spark/pull/28492

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.1.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-05-10 Thread Apache Spark (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17103915#comment-17103915
 ] 

Apache Spark commented on SPARK-27249:
--

User 'nafshartous' has created a pull request for this issue:
https://github.com/apache/spark/pull/28492

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.1.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-04-17 Thread Nick Afshartous (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17086029#comment-17086029
 ] 

Nick Afshartous commented on SPARK-27249:
-

[~enrush] Hi Everett,

Using the {{Iterator}} approach would seem to deviate from the existing 
{{Transformer}} contract.  More specifically, the {{transform}} function should 
output a new {{DataFrame}} object.  What I would propose is adding a new 
function {{Transformer.compose}} to allow the composition of {{Transformers}}.  

{code}
  def compose(other: Transformer): Transformer = {
new Transformer {
  override def transform(dataset: Dataset[_]): DataFrame = {
other.transform(this.transform(dataset));
  }
...
{code}

Then one could {{compose}} {{Transformers}} which effectively would enable 
multi-column transformations.  

{code}
 val dataFrame = ...
 val transformers = List(transformer1, transformer2, transformer3)
 val multiColumnTransformer = transformers.reduce((x, y) => x.compose(y))

multiColumnTransformer.transform(dataFrame)
{code}

I'd be happy to submit a PR if this meets your requirments.

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.1.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-04-09 Thread Everett Rush (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17079337#comment-17079337
 ] 

Everett Rush commented on SPARK-27249:
--

Hi Nick,

 

I think the solution could make use of the mapPartitions method, but still 
there should be a multicolumn transformer class. The unary transformer is very 
limiting.

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.1.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-04-08 Thread Nick Afshartous (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17078751#comment-17078751
 ] 

Nick Afshartous commented on SPARK-27249:
-

[~enrush] Hi Everett, checking back on my question in the last comment.  

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.1.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-01-17 Thread Nick Afshartous (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17018329#comment-17018329
 ] 

Nick Afshartous commented on SPARK-27249:
-

[~enrush] Hi Everett, 
The {{Dataset}} API has an experimental function {{mapPartitions}} for 
transforming {{Dataset}} .  Does this satisfy your requirements ?  

https://spark.apache.org/docs/latest/api/scala/index.html#org.apache.spark.sql.Dataset

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.0.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
> Attachments: Screen Shot 2020-01-17 at 4.20.57 PM.png
>
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-01-17 Thread Nick Afshartous (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17018105#comment-17018105
 ] 

Nick Afshartous commented on SPARK-27249:
-

Thanks Everett, and can someone with permission assign this ticket to me.

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.0.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-01-09 Thread Everett Rush (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17012229#comment-17012229
 ] 

Everett Rush commented on SPARK-27249:
--

[~nafshartous] 

Hi Nick,

 

I would like to have a "MultiColumnTransformer class" in Spark. I should be 
able to subclass this transformer. I would like the api to be similar to 
UnaryTranformer. So I provide a transformation function and a new schema. Then 
Spark handles the encoding back to a DataFrame and optimizes the computation 
however it can. 

 

class ExampleMulticolumn(override val uid: String, envVars: Map[String, String])
 extends MultiColumnTransformer[ExampleMulticolumn]
 with HasInputCol with DefaultParamsWritable {

 def this() = this(Identifiable.randomUID("exampleMulticolumn"), Map())

 // developer provides the new schema for dataframe
 val newSchema: StructType
 
 override protected def transformFunc: Iterator[Row] => Iterator[Row] = {
 iter => {
 // connect to database
 // iterate over rows in partition
 val new_iter = iter.map{
 row =>
 // do some computation
 row
 }
 new_iter
 }
 }
 override def copy(extra: ParamMap): ExampleMulticolumn = defaultCopy(extra)

}

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.0.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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[jira] [Commented] (SPARK-27249) Developers API for Transformers beyond UnaryTransformer

2020-01-08 Thread Nick Afshartous (Jira)


[ 
https://issues.apache.org/jira/browse/SPARK-27249?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17010756#comment-17010756
 ] 

Nick Afshartous commented on SPARK-27249:
-

I could try and look into this.  Could someone validate that this feature is 
still needed ?  

> Developers API for Transformers beyond UnaryTransformer
> ---
>
> Key: SPARK-27249
> URL: https://issues.apache.org/jira/browse/SPARK-27249
> Project: Spark
>  Issue Type: New Feature
>  Components: ML
>Affects Versions: 3.0.0
>Reporter: Everett Rush
>Priority: Minor
>  Labels: starter
>   Original Estimate: 96h
>  Remaining Estimate: 96h
>
> It would be nice to have a developers' API for dataset transformations that 
> need more than one column from a row (ie UnaryTransformer inputs one column 
> and outputs one column) or that contain objects too expensive to initialize 
> repeatedly in a UDF such as a database connection. 
>  
> Design:
> Abstract class PartitionTransformer extends Transformer and defines the 
> partition transformation function as Iterator[Row] => Iterator[Row]
> NB: This parallels the UnaryTransformer createTransformFunc method
>  
> When developers subclass this transformer, they can provide their own schema 
> for the output Row in which case the PartitionTransformer creates a row 
> encoder and executes the transformation. Alternatively the developer can set 
> output Datatype and output col name. Then the PartitionTransformer class will 
> create a new schema, a row encoder, and execute the transformation.



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