Source: https://dev-docs.nebula-graph.io/v5.3.2/clients/spark-connector/config/reader-options/
Documentation version: v5.3.2

# Reader options

The following table lists the options that you can use to configure the reader.

 | Option | Description | Required | Default value | Introduced in
 | `type` | The type of the reader. Valid values: `node`, `edge`, and `gql`. | Yes | N/A | 5.0
 | `operate_type` | The operation type of the reader. Valid value: `read`. | Yes | N/A | 5.0
 | `graph_address` | The IP address and port of the Graph service. Separate multiple entries with commas (,). For example: `ip1:port1,ip2:port2,...` | Yes | N/A | 5.0
 | `user` | The username of the Graph service. | No | `root` | 5.0
 | `passwd` | The password used to authenticate a user. | Yes | N/A | 5.0
 | `schema` | The schema that contains the graph from which data is read. | No | `/default_schema` | 5.0
 | `graph_name` | The name of the graph from which data is read. | Yes | N/A | 5.0
 | `label` | The name of the node type or edge type from which data is read. Required if `type` is set to `node` or `edge`. | No | N/A | 5.0
 | `return_cols` | The properties of the node type or edge type to read. Separate multiple properties with commas (,). 
If not specified or set to `null`, all properties of the node type or edge type are read. 
If set to `""` for a node type, only properties that constitute the primary key of the node type are read. 
If set to `""` for an edge type, only properties that constitute the primary keys of the source and destination node types of the edge type are read. | No | `null` | 5.0
 | `gql` | The GQL query statement that is used to read data. Required if `type` is set to `GQL`. | No | N/A | 5.0
 | `batch_size` | The maximum number of data entries to read in each request. Required if `type` is set to `node` or `edge`. | No | `1000` | 5.0
 | `partition_number` | The number of Spark partitions to read data in parallel. Required if `type` is set to `node` or `edge`. | No | `1` | 5.0
 | `timeout` | The connection timeout for read requests in seconds. | No | `3` | 5.0
 | `server_ping_timeout` | The timeout for pinging the Graph service in seconds. | No | `3` | 5.2
 | `execution_retry` | The number of retries when a connection fails. | No | `3` | 5.0
 | `execution_retry_interval` | The interval between retries in milliseconds. | No | `0` | 5.0
 | `enable_tls` | Whether to enable TLS encryption. | No | `false` | 5.1
 | `disable_verify_server_cert` | Whether to disable server certificate verification. | No | `false` | 5.1
 | `tlsCa` | The path to the CA (Certificate Authority) certificate file, which is used to verify the server's certificate. Required if `enable_tls` is set to `true` and `disable_verify_server_cert` is set to `false`. | No | N/A | 5.1
 | `tlsCert` | The path to the certificate file of the client. Required if `tls_client_verify` is set to `true` in the configuration file of NebulaGraph Database Developer Edition's Graph service. | No | N/A | 5.1
 | `tlsKey` | The path to the private key file of the client. Required if `tls_client_verify` is set to `true` in the configuration file of NebulaGraph Database Developer Edition's Graph service. | No | N/A | 5.1