microsoft/graphrag · error · ValueError

Either connection_string or account_url must be provided.

Error message

Either connection_string or account_url must be provided.

What it means

An internal consistency check in BlobWorkflowLogger.__init__: the code took the account_url branch (connection_string was falsy) but account_url is also None, meaning neither credential option is available. It is effectively unreachable if the earlier both-None check passed and a non-empty connection string exists; it fires when connection_string is empty string/whitespace (falsy but not None) and account_url is None.

Source

Thrown at packages/graphrag/graphrag/logger/blob_workflow_logger.py:52

        if container_name is None:
            msg = "No container name provided for blob storage."
            raise ValueError(msg)
        if connection_string is None and account_url is None:
            msg = "No storage account blob url provided for blob storage."
            raise ValueError(msg)

        self._connection_string = connection_string
        self.account_url = account_url
        self._base_dir = base_dir

        if self._connection_string:
            self._blob_service_client = BlobServiceClient.from_connection_string(
                self._connection_string
            )
        else:
            if account_url is None:
                msg = "Either connection_string or account_url must be provided."
                raise ValueError(msg)

            self._blob_service_client = BlobServiceClient(
                account_url,
                credential=DefaultAzureCredential(),
            )

        self._container_name = container_name
        self._rotate_blob(blob_name or None)

    def emit(self, record) -> None:
        """Emit a log record to blob storage."""
        try:
            # Create JSON structure based on record
            log_data = {
                "type": self._get_log_type(record.levelno),
                "data": record.getMessage(),
            }

View on GitHub (pinned to f40e9a26ce)

Solutions

1. Ensure connection_string is a non-empty value, not '' — check the env var isn't defined-but-empty
2. Pass a valid account_url when using DefaultAzureCredential instead of a connection string
3. Trim/validate credential strings in config loading before constructing the logger

Example fix

# before
BlobWorkflowLogger(container_name='c', connection_string=cfg.conn_str)  # conn_str == ''
# after
conn = (cfg.conn_str or '').strip()
BlobWorkflowLogger(container_name='c', connection_string=conn or None, account_url=cfg.account_url)

conn = (cfg.connection_string or '').strip()
url = (cfg.account_url or '').strip()
assert conn or url, 'need connection_string or account_url'
logger = BlobWorkflowLogger(container_name='c', connection_string=conn or None, account_url=url or None)

When it happens

Trigger: Passing connection_string='' (empty string) with account_url=None — the first check passes because connection_string is not None, but the falsy value routes to the else branch. Also any refactor that clears account_url between the two checks.

Common situations: Env var set but empty (AZURE_STORAGE_CONNECTION_STRING="" in .env); config templating that substitutes empty values; whitespace-only secrets in CI secrets.

Related errors

• No storage account blob url provided for blob storage.
• AzureBlobStorage requires only one of connection_string or a
• AzureBlobStorage requires either a connection_string or acco
• Blob storage does yet not support listing keys.
• Container name must be between 3 and 63 characters long and

AI-assisted analysis of microsoft/graphrag@f40e9a26ce (2026-08-27). Data as JSON: /api/errors/5c359be58f906947. Report an issue: GitHub.