pentaho/pentaho-kettle · error · org.pentaho.di.core.exception.KettleFileException

: Unable to read row metadata from input stream

Error message

${toString()} : Unable to read row metadata from input stream

What it means

In the RowMeta(InputStream) constructor loop, any non-EOF exception while reading a field type, creating the value meta, or reading its metadata is wrapped in KettleFileException "<rowMeta.toString()> : Unable to read row metadata from input stream". This covers both I/O faults and value-meta creation failures (e.g. unknown value type id) during field deserialization.

Solutions

  1. Enable a debug log on the stream to dump raw bytes and confirm byte alignment/format of the metadata.
  2. Align PDI versions between sender and receiver so all value type ids are supported.
  3. Ensure all value-type plugins are installed so createValueMeta can resolve every type id.
  4. Re-transmit the metadata if the stream is corrupted.

Example fix

// before
RowMeta rowMeta = new RowMeta(inputStream);
// after
try {
  RowMeta rowMeta = new RowMeta(inputStream);
} catch (KettleFileException e) {
  log.error("Row metadata read failed: " + e.getMessage(), e);
  verifySenderVersionMatches();
  inputStream = reconnect();
  RowMeta rowMeta = new RowMeta(inputStream);
}
Defensive patterns

Strategy: validation

Validate before calling

byte[] raw = readAllBytes(inputStream);
// verify declared field count matches parseable content before constructing RowMeta
RowMeta rowMeta = new RowMeta(new ByteArrayInputStream(raw));

Try / catch

try {
  RowMeta rowMeta = new RowMeta(inputStream);
} catch (KettleFileException e) {
  log.error("Field-level metadata read failed: " + e.getMessage(), e);
  verifySenderPdiVersion();
  ensureValueMetaPluginsInstalled();
}

Prevention

When it happens

Trigger: new RowMeta(inputStream) where ValueMetaFactory.createValueMeta(type) fails on an unknown/unsupported type id, readMetaData throws, or a non-EOF IOException occurs while reading a field.

Common situations: Reading metadata serialized by a newer PDI version with value types the current version does not know; corrupted stream bytes shifting type ids; missing value-type plugin jars.

Related errors

AI-assisted analysis of pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/dfeb632a6a338f2f. Report an issue: GitHub.

Appendix: source

Thrown at core/src/main/java/org/pentaho/di/core/row/RowMeta.java:742

    } catch ( SocketTimeoutException e ) {
      throw e;
    } catch ( EOFException e ) {
      throw new KettleEOFException(
        "End of file while reading the number of metadata values in the row metadata", e );
    } catch ( IOException e ) {
      throw new KettleFileException( "Unable to read nr of metadata values: " + e.toString(), e );
    }

    for ( int i = 0; i < nr; i++ ) {
      try {
        int type = inputStream.readInt();
        ValueMetaInterface valueMeta = ValueMetaFactory.createValueMeta( type );
        valueMeta.readMetaData( inputStream );
        addValueMeta( valueMeta );
      } catch ( EOFException e ) {
        throw new KettleEOFException( e );
      } catch ( Exception e ) {
        throw new KettleFileException( toString() + " : Unable to read row metadata from input stream", e );
      }

    }
  }

  @Override
  public Object[] readData( DataInputStream inputStream ) throws KettleFileException, SocketTimeoutException {
    lock.readLock().lock();
    try {
      Object[] data = new Object[ size() ];
      for ( int i = 0; i < size(); i++ ) {
        data[ i ] = getValueMeta( i ).readData( inputStream );
      }
      if ( size() == 0 ) {
        try {
          inputStream.readBoolean();
        } catch ( EOFException e ) {
          throw new KettleEOFException( e );

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