---
alias: user-guide-automation-task-opcua-readfile
tags:
- automation tasks
description: "This task retrieves data from a file on an OPC UA server using a driver"
---

# Read File

This task reads data from a file on OPC UA server using the File Transfer feature. To be used with OPC UA driver in Client mode.

![Screenshot showing settings for reading a file, with options including filename.](./images/read_file_parameters.png)

## Inputs

| Name     | Data Type | Description                                |
| -------- |  ---------| ------------------------------------------ |
| nodeId   | `String`  | The node id where the file will be read    |
| Activate |  `any`    | Activate the task                          |

## Outputs

| Name    | Data Type | Description                                            |
| ------  | --------- | ------------------------------------------------------ |
| rawData | `Buffer`  | The raw data from  the file                            |
| Success | `Boolean` | If there was no problem emits a true                   |
| Error   | `Error`   | Error that occurred during the processing of this task |

## Settings

On the *General Tab*, you have the usual settings and the following settings:

| Name                       | Data Type | Default       | Description                                                                                          |
| -------------------------- | --------- | ------------- | ---------------------------------------------------------------------------------------------------------------------------------------------- |
| File Node Id               | `String`  |               | The node id where the file is                                                                                                                  |
| Read File Command          | `String`  | .Read         | The syntax that allows to call the read command, for instance, SomeFileIdentification.Read. Useful to prevent break of compatibilities.        |
| Get Position Command       | `String`  | .GetPosition  | The syntax that allows to call the read command, for instance, SomeFileIdentification.GetPosition. Useful to prevent break of compatibilities. |
| Delete File Command        | `String`  | .Delete       | The syntax that allows to call the delete command, for instance, SomeFileIdentification.Delete. Useful to prevent break of compatibilities.    |
| File Chunk Size            | `Number`  | 0             | Configuration for the size of the Chunks. If no value or a zero has been provided, the chunks will default to maximum allowed on the protocol (16000000 Bytes)   |
| File Size Syntax           | `String`  | .Size         | The syntax that allows get size attribute, for instance, SomeFileIdentification.Size. Useful to prevent break of compatibilities.              |
| Automatically Delete File  | `Boolean` | false         | Flag to indicate if the file shall be deleted after a successful call                                                                          |
| Directory Node Id          | `String`  |               | The node id of the directory where the file is located. Necessary for the Delete command. Only can be called from the direcotry object         |

![Screenshot showing settings for reading a file, with options including filename.](./images/read_file_parameters.png)

## Behavior

Activate will trigger a message to the driver. The contents of the message are the values received in the inputs.

## Remarks

* All the communication with the equipment is handled by the driver in the backend.