Hacktoberfest 2026: le issue che i maintainer hanno segnato per ottobre, aperte e adatte ai principianti. Sfoglia le issue Hacktoberfest

[Feature Request]: Implement JsonIO.read() / readRows() for the Java SDK

Aperta
  • Qualcosa non va?
#40,086 1 commento 0 reazioni 1 assegnatario Vedi su GitHub

I maintainer di solito rispondono entro 1 giorno

@nitinware ci sta già lavorando.

Dal 9/9/2026.

Valutazione

Questa issue non è ancora stata valutata.

Descrizione

io java new feature P2
What would you like to happen?

Motivation

The Java JsonIO connector (sdks/java/io/json/.../JsonIO.java) currently supports only writing withJsonIO.write() and JsonIO.writeRows(). There is no read path. The connector's own class Javadoc acknowledges this gap:

"Reading from JSON files is not yet implemented in Java. Please see
https://github.com/apache/beam/issues/24552."

That linked issue (#24552) is actually titled "Implement CsvIO.Read" and is closed as not planned, CsvIO.Read was subsequently implemented under a different path, so there is currently no live tracking issue for JSON reading, and the Javadoc reference is stale. This issue is intended to be that tracking issue.

Proposal

Add a read/parse surface to JsonIO symmetric to the existing write surface
and mirroring the pattern CsvIO already established:

JsonIO.parse(Class<T> klass)      // JSON records -> user type T
JsonIO.parseRows(Schema schema)   // JSON records -> Row

modeled on CsvIO.parse(Class, CSVFormat) (CsvIO.java:419) and CsvIO.parseRows(Schema, CSVFormat) (CsvIO.java:497), including their CsvIOParse result-and-error-handling pattern.

Why this is tractable

The core JSON→Row conversion already exists and is reusable:

  • JsonUtils.getJsonStringToRowFunction(Schema)
    (sdks/java/core/.../schemas/utils/JsonUtils.java:104)
  • JsonUtils.getJsonBytesToRowFunction(Schema) (line 93)
  • JsonUtils.beamSchemaFromJsonSchema(String) (line 201)

The work is primarily wiring these into a read PTransform over FileIO.match() + line reading, following the CsvIO parse structure not new parsing logic.

Testing plan

  • Unit tests mirroring CsvIO parse tests: schema validation, type conversion to both Row and custom user classes, error/failure routing.
  • Round-trip test: write JSON via JsonIO.write(), read it back via JsonIO.parseRows(), assert equality.
  • No new dependencies- JSON schema/parse machinery is already in sdks/java/core.
Issue Priority

Priority: 2 (default / most feature requests should be filed as P2)

Issue Components
  • Component: Python SDK
  • Component: Java SDK
  • Component: Go SDK
  • Component: Typescript SDK
  • Component: IO connector
  • Component: Beam YAML
  • Component: Beam examples
  • Component: Beam playground
  • Component: Beam katas
  • Component: Website
  • Component: Infrastructure
  • Component: Spark Runner
  • Component: Flink Runner
  • Component: Prism Runner
  • Component: Twister2 Runner
  • Component: Hazelcast Jet Runner
  • Component: Google Cloud Dataflow Runner
Lingua principale
Java
Stelle
8.7k
Fork
4.7k
Merge medio
2g 4h
PR unite (30g)
278

Preparare l'ambiente

Come iniziare

  1. Leggi tutta la issue e poi la guida ai contributi del progetto.
  2. Commenta sulla issue per dire che te ne occupi tu — evita che due persone facciano lo stesso lavoro.
  3. Fai un fork del repository e lavora su un branch.
  4. Apri una pull request che faccia riferimento al numero della issue.

Altre issue di apache/beam

Tutte le issue di apache/beam

Issue simili

Altre issue su Java

Ricevi le nuove issue nella tua casella

Un breve riepilogo di issue GitHub adatte ai principianti.