apache/hadoop · error · IllegalArgumentException

{str} is not a valid GET operation.

Error message

{str} is not a valid GET operation.

What it means

GetOpParam parses the 'op' query parameter of WebHDFS/HttpFS GET requests against the Op enum in GetOpParam.java:25-73 (OPEN, GETFILESTATUS, LISTSTATUS, GETCONTENTSUMMARY, GETQUOTAUSAGE, GETFILECHECKSUM, GETHOMEDIRECTORY, GETDELEGATIONTOKEN, GET_BLOCK_LOCATIONS, GETFILEBLOCKLOCATIONS, GETACLSTATUS, GETXATTRS, GETTRASHROOT, LISTXATTRS, GETALLSTORAGEPOLICY, GETSTORAGEPOLICY, GETECPOLICY, CHECKACCESS, LISTSTATUS_BATCH, GETSERVERDEFAULTS, GETSNAPSHOTDIFF, GETSNAPSHOTDIFFLISTING, GETSNAPSHOTTABLEDIRECTORYLIST, GETLINKTARGET, GETFILELINKSTATUS, GETSTATUS, GETECPOLICIES, GETECCODECS, GETTRASHROOTS, GETSNAPSHOTLIST, NULL). Matching is case-insensitive (Enum.valueOf after toUpperCase); anything else throws this IllegalArgumentException, surfaced as HTTP 400.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/resources/GetOpParam.java:135

      return NAME + "=" + this;
    }
  }

  private static final Domain<Op> DOMAIN = new Domain<>(NAME, Op.class);

  /**
   * Constructor.
   * @param str a string representation of the parameter value.
   */
  public GetOpParam(final String str) {
    super(DOMAIN, getOp(str));
  }

  private static Op getOp(String str) {
    try {
      return DOMAIN.parse(str);
    } catch (IllegalArgumentException e) {
      throw new IllegalArgumentException(str + " is not a valid " + Type.GET
          + " operation.");
    }
  }

  @Override
  public String getName() {
    return NAME;
  }
}

View on GitHub (pinned to 2add963021)

Solutions

1. Correct the op value to one of the GET Op enum constants listed in GetOpParam.java:25-73 (e.g. GETFILESTATUS, LISTSTATUS, OPEN).
2. Verify the HTTP method: GET-only ops fail here if sent as PUT/POST and vice versa.
3. If the op looks valid, check NameNode version support — newer ops (GETQUOTAUSAGE, GETSNAPSHOTDIFFLISTING) need Hadoop 3.x; use the older equivalent (GETCONTENTSUMMARY) on 2.x.
4. Prefer the webhdfs:// Java FileSystem client, which only emits supported op values.

Example fix

# before
curl -i "http://nn:9870/webhdfs/v1/tmp/f?op=GETFILESTAT"
# after
curl -i "http://nn:9870/webhdfs/v1/tmp/f?op=GETFILESTATUS"

private static final Set<String> GET_OPS = Set.of("OPEN","GETFILESTATUS","LISTSTATUS","GETCONTENTSUMMARY","GETQUOTAUSAGE","GETFILECHECKSUM","GETHOMEDIRECTORY","GETDELEGATIONTOKEN","GETFILEBLOCKLOCATIONS","GETACLSTATUS","GETXATTRS","LISTXATTRS","GETTRASHROOT","GETALLSTORAGEPOLICY","GETSTORAGEPOLICY","GETECPOLICY","CHECKACCESS","LISTSTATUS_BATCH","GETSERVERDEFAULTS","GETSNAPSHOTDIFF","GETSNAPSHOTDIFFLISTING","GETSNAPSHOTTABLEDIRECTORYLIST","GETLINKTARGET","GETFILELINKSTATUS","GETSTATUS","GETECPOLICIES","GETTRASHROOTS","GETSNAPSHOTLIST");
static String checkedGetOp(String op) {
  String v = op.toUpperCase(Locale.ROOT);
  if (!GET_OPS.contains(v)) throw new IllegalArgumentException("unsupported GET op for this cluster: " + op);
  return v;
}

static boolean isSupportedGetOp(String op, Set<String> supported) {
  return op != null && supported.contains(op.toUpperCase(Locale.ROOT));
}

try { ... } catch (IOException e) {
  RemoteException re = (RemoteException) (e instanceof RemoteException ? e : null);
  if (re != null && re.getClassName().endsWith("IllegalArgumentException") && re.getMessage().contains("valid GET operation")) {
    // typo or version drift: cross-check op against the cluster's hadoop version
  }
}

When it happens

Trigger: GET ?op=getfilestat (missing 'us'), ?op=LIST (instead of LISTSTATUS), ?op=GETFILELOCATION (private op, not in this enum), or using a PUT/POST op with GET, e.g. ?op=SETPERMISSION or ?op=APPEND on a GET request.

Common situations: Version drift: ops added in newer Hadoop releases (GETQUOTAUSAGE, GETSNAPSHOTDIFFLISTING, GETECCODECS, GETSERVERDEFAULTS) fail with this exact error against older NameNodes; mixing op names between WebHDFS and HttpFS docs; shell scripts with case-agnostic typos that survive review because the value looks plausible.

Related errors

• {str} is not a valid DELETE operation.
• {str} is not a valid POST operation.
• {str} is not a valid PUT operation.
• Storage policy name is empty.
• {} is not supported

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/0c456f511ed5ec21. Report an issue: GitHub.