apache / apache/parquet-java

parquet-cli unable to read UUID values

Ouverte
#1,641 13 commentaires 0 réactions 0 personnes assignées Voir sur GitHub
Component: CLI Component: Parquet Priority: Minor Type: bug
Langage dominant
Java
Étoiles
3.1k
Forks
1.6k
Merge moyen
3 j 12 h
PR mergées (30 j)
33

Description

I am finding that parquet-cli throws when trying to read UUID values. 

Attached to this bug report is a parquet file with 2 columns, message encoded as byte-array and number encoded as fixed length byte array (UUID). This file was written by my .net implementation of parquet specification. The file has one row worth of data and is readable by parquet-cpp.

Schema as read by parquet-cli:

message root

{   required binary Message (STRING);   required fixed_len_byte_array(16) Number (UUID); }

Values as read by parquet-cpp:

— Values —
Message                       |Number                        |
First record                  |215 48 212 219 218 57 169 67 166 116 7 79 44 227 50 17 |

 

Here is the exception stack from parquet-cli when trying to read uuid values:
```java

Caused by: org.apache.parquet.io.ParquetDecodingException: The requested schema is not compatible with the file schema. incompatible types: required binary Number (STRING) != required fixed_len_byte_array(16) Number (UUID)
        at org.apache.parquet.io.ColumnIOFactory$ColumnIOCreatorVisitor.incompatibleSchema(ColumnIOFactory.java:101)
        at org.apache.parquet.io.ColumnIOFactory$ColumnIOCreatorVisitor.visit(ColumnIOFactory.java:93)
        at org.apache.parquet.schema.PrimitiveType.accept(PrimitiveType.java:602)
        at org.apache.parquet.io.ColumnIOFactory$ColumnIOCreatorVisitor.visitChildren(ColumnIOFactory.java:83)
        at org.apache.parquet.io.ColumnIOFactory$ColumnIOCreatorVisitor.visit(ColumnIOFactory.java:57)
        at org.apache.parquet.schema.MessageType.accept(MessageType.java:55)
        at org.apache.parquet.io.ColumnIOFactory.getColumnIO(ColumnIOFactory.java:162)
        at org.apache.parquet.hadoop.InternalParquetRecordReader.checkRead(InternalParquetRecordReader.java:135)
        at org.apache.parquet.hadoop.InternalParquetRecordReader.nextKeyValue(InternalParquetRecordReader.java:225)

```
 I debugged parquet-cli code and found that parquet-cli is trying to project the UUID as a string and later on that throws as these types are not compatible? 

 

Source code references:

At AvroReadSupport.java, line 97

~~~~~~~~~~~~

    String requestedProjectionString = configuration.get(AVRO_REQUESTED_PROJECTION);

    if (requestedProjectionString != null)

{       Schema avroRequestedProjection = new Schema.Parser().parse(requestedProjectionString);       projection = new AvroSchemaConverter(configuration).convert(avroRequestedProjection);     }

~~~~~~~~~~~~

 

Debugger values for

requestedProjectionString=

{"type":"record","name":"root","fields":[
{"name":"Message","type":"string"}

,\{"name":"Number","type":{"type":"string","logicalType":"uuid"}}]}

[Note that `Number` now has a type of `string` and a logicalType of `uuid`]

 

At ColumnIOFactory.java line 93

~~~~~~~~~~~~

incompatibleSchema(primitiveType, currentRequestedType);

~~~~~~~~~~~~

Debugger values for 

primitiveType = required fixed_len_byte_array(16) Number (UUID)

currentRequestedType = required binary Number (STRING)

 

and this will throw.

 

If I skip over the projection code in AvroReadSupport, parquet-cli is able to read my file.

I am not sure if the bug is in parquet-cli or parquet-mr or in the library I used to encode this file. The fact that parquet-cpp is able to read it gives me some confidence to say that the problem is either in parquet-cli or parquet-mr.

Please point me in the right direction if I could verify this UUID roundtripping purely from parquet-mr itself in form of an unit-test. Happy to contribute tests or fix if needed.

**Reporter**: [Balaji K](https://issues.apache.org/jira/secure/ViewProfile.jspa?name=gamaken)
#### Original Issue Attachments:
- [guid.parquet](https://issues.apache.org/jira/secure/attachment/13042816/guid.parquet)

**Note**: *This issue was originally created as [PARQUET-2140](https://issues.apache.org/jira/browse/PARQUET-2140). Please see the [migration documentation](https://issues.apache.org/jira/browse/PARQUET-2502) for further details.*

Guide de contribution

Aucun guide de contribution indexé pour ce dépôt

Piste de recherche

Commencez par AvroReadSupport.java autour de la conversion de projection demandée et par ColumnIOFactory.java autour de la vérification des schémas incompatibles. Reproduisez l’échec avec le fichier guid.parquet joint ou avec un test unitaire parquet-mr utilisant le schéma UUID présenté dans le rapport. C’est terminé lorsque parquet-cli ou le chemin de lecture parquet-mr pertinent peut lire l’UUID fixed_len_byte_array sans l’exception d’incompatibilité de schéma.

Rédigé par le modèle d'indexation à partir du texte de l'issue.

Évaluation

Stack technique
java
Domaine
data-engineering
Type d'issue
Bug
Difficulté
4/5
Temps estimé
3-5 jours
Activité
Calme
Clarté
Plutôt claire
Accessibilité débutants
45/100

Recevez les nouvelles issues par e-mail

Un résumé court des issues GitHub adaptées aux débutants.