pentaho/pentaho-kettle · error · KettleFileException

Row.ErrorWritingRow

Error message

Row.ErrorWritingRow

What it means

setEnvironmentVar requires exactly 2 arguments (property name and value). This is an argument-count guard in ScriptValuesAddedFunctions.java: when ArgList.length != 2, the function throws a Rhino runtime error instead of silently proceeding. It exists because the underlying System.setProperty call needs both a key and a value.

Solutions

1. Supply both arguments: setEnvironmentVar('MY_KEY', 'value').
2. If the value may be absent, default it explicitly before calling: var v = x === undefined ? '' : x.
3. Count arguments before calling to confirm exactly two are passed.

Example fix

// before
setEnvironmentVar("MY_KEY");
// after
setEnvironmentVar("MY_KEY", "myValue");

var args = [key, value];
if (args.length !== 2) throw new Error("setEnvironmentVar needs name and value");

null

try {
  setEnvironmentVar(key, value === undefined ? "" : value);
} catch (e) {
  // log and continue with a safe default
}

When it happens

Trigger: Calling setEnvironmentVar() with 0, 1, or 3+ arguments from JavaScript code in the Script Values / Modified Java Script Value step, e.g. setEnvironmentVar('MY_KEY') forgetting the value.

Common situations: Copy-pasted snippets where the second argument was dropped; dynamic argument construction where an optional value was undefined and removed; migrating scripts from other engines that tolerate one-argument calls.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• Row.EndOfFileReached
• Please provide a valid date to the function call date2str.
• Row.EndOfFileReadingRow
• Row.RowError
• The function call copyFile is not valid.

AI-assisted analysis of pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/328b0eeaf0f692ce. Report an issue: GitHub.

Appendix: source

Thrown at core/src/main/java/org/pentaho/di/compatibility/Row.java:461

    // Write all values in the row
    for ( int i = 0; i < size(); i++ ) {
      getValue( i ).writeObj( dos );
    }
  }

  /**
   * Write the content of the row to a DataOutputStream.
   *
   * @param dos
   *          The DataOutputStream to write to
   * @throws KettleFileException
   *           if an error occurs.
   */
  public void write( DataOutputStream dos ) throws KettleFileException {
    try {
      writeObj( dos );
    } catch ( Exception e ) {
      throw new KettleFileException( BaseMessages.getString( PKG, "Row.ErrorWritingRow" ), e );
    }
  }

  private void readObj( DataInputStream dis ) throws IOException {
    // First handle the number of fields in a row
    int size = dis.readInt();

    // get all values in the row
    for ( int i = 0; i < size; i++ ) {
      Value v = new Value();
      v.readObj( dis );
      addValue( v );
    }
  }

  /**
   * Read a row of Values from an input-stream.
   *

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