apache/beam · error · ValueError

URI must be provided for Milvus connection

Error message

URI must be provided for Milvus connection

What it means

MilvusConnectionParameters.__post_init__ requires a non-empty uri (e.g. 'https://localhost:19530' or 'milvus-demo.db.zillizcloud.com:19530'); without a URI there is no endpoint to attach the Milvus client to.

Solutions

1. Pass a uri, e.g. MilvusConnectionParameters(uri='http://localhost:19530')
2. For Zilliz Cloud / Milvus Lite use the appropriate https URI or local file path
3. Verify the env var/config feeding uri is set and non-empty before constructing
4. Ensure uri is a string, not None passed explicitly

Example fix

// before
params = MilvusConnectionParameters(token=token)
// after
params = MilvusConnectionParameters(uri="http://localhost:19530", token=token)

uri = os.environ.get("MILVUS_URI")
if not uri:
    raise ValueError("MILVUS_URI must be set before creating Milvus connection params")

def has_uri(params) -> bool:
    return isinstance(params.uri, str) and params.uri != ""

When it happens

Trigger: Constructing MilvusConnectionParameters() with uri=None or empty string '' — e.g. omitting the uri kwarg or passing Milvus uri via a variable that is unset/empty.

Common situations: Missing MILVUS_URI environment variable; building connection params from a config dict where the uri key is absent; local Milvus setups forgetting the 'http://localhost:19530' endpoint.

Understand the failure class

Background: "is required", "must be set", "missing required field": configuration validation errors across open-source libraries — this error's family across 36 libraries.

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AI-assisted analysis of apache/beam@12126d8942 (2026-09-13). Data as JSON: /api/errors/8dcfab2f8c2b9766. Report an issue: GitHub.

Appendix: source

Thrown at sdks/python/apache_beam/ml/rag/utils.py:68

      and not using token authentication.
    db_name: Database Name to connect to. Specifies which Milvus database to
      use. Defaults to 'default'.
    token: Authentication token as an alternative to username/password.
    timeout: Connection timeout in seconds. Uses client default if None.
    kwargs: Optional keyword arguments for additional connection parameters.
      Enables forward compatibility.
  """
  uri: str
  user: str = field(default_factory=str)
  password: str = field(default_factory=str)
  db_name: str = "default"
  token: str = field(default_factory=str)
  timeout: Optional[float] = None
  kwargs: dict[str, Any] = field(default_factory=dict)

  def __post_init__(self):
    if not self.uri:
      raise ValueError("URI must be provided for Milvus connection")

    # Generate unique alias if not provided. One-to-one mapping between alias
    # and connection - each alias represents exactly one Milvus connection.
    if "alias" not in self.kwargs:
      alias = f"milvus_conn_{uuid.uuid4().hex[:8]}"
      self.kwargs["alias"] = alias


class MilvusHelpers:
  """Utility class providing helper methods for Milvus vector db operations."""
  @staticmethod
  def sparse_embedding(
      sparse_vector: Optional[tuple[list[int], list[float]]]
  ) -> Optional[dict[int, float]]:
    if not sparse_vector:
      return None
    # Converts sparse embedding from (indices, values) tuple format to
    # Milvus-compatible values dict format {dimension_index: value, ...}.

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