---
title: File Reading Processor
slug: litmusedge-v2/file-reading-processor
docTags: 
createdAt: 2024-10-21T17:54:09.977Z
---

The **File Reading** processor function allows users to read content from a specified file and pass it as a string in the output payload, with customizable parameters for filename management, file size limits, and re-reading intervals.

# File Reading Overview

- Reads a file and passes it as a string in the **"value"** field of the output payload
- If the ***File Name*** field is empty, this processor will attempt to get filename from incoming payload field **"filename"**
  - Otherwise, the filename entered here field will be honored
- If the **"Generate Filename From Expression"** option is enabled, the filename will be evaluated as expression.
  - For example, if you want to get the filename from "path" and name" properties of incoming connection "AAA", your expression could be: **AAA\_path + AAA\_name + ".txt"**
  - Please note that static text in expressions should be put into quotes
- Time interval, in seconds, allows a file to be re-read even if the file is unmodified
  - Typically, an input message triggers a file read, if the file is unmodified since the last read
  - The specified time interval resets the “unmodified” status, so that the file can be read at the next input trigger
  - Any change of the processor’s setting also resets the "unmodified" status
  - Setting **0** means that the “unmodified” status is never reset, and the file is only read if modified
- **"File Size Limit"**: If the file/s is bigger than the specified amount of megabytes, reading action on that file/s will be skipped
  - ***Caution!*** If this limit is set to **0**, files of all sizes will be read, but it can potentially lead to overuse of CPU, memory and storage space
- If ***"Input File Type"*** is set to **value only** processor will set incoming data to **"value""** payload field.
- If ***"Input File Type"*** is set to **CSV** following options will affect input:
  - **CSV Comma** contains CSV-file delimiter (only first character will be used from string entered)
  - **CSV Columns Mode** controls how processor will determine data column names.
    - If this option is set to "indexed" mode processor will assume CSV file doesn't have header and will generate payload field names as "FieldXXX"
    - If this option is set to "from header" mode processor will get payload field names from CSV file header
    - If this option is set to "custom" mode processor will get payload field names **CSV Custom Columns** string
- **"Data Output Mode"**: specifies whether data from file would be sent in one message on record-by-record.
  - Please note: A** message per record** data output mode is not supported for binary or JSON files

# File Reading Parameters

| **Parameters**                    | **Details**                                                                                                             |
| --------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| File Name                         | Specifies the name of the file to be read.                                                                              |
| Generate Filename From Expression | Enables filename evaluation as an expression when activated, allowing for dynamic filename assignment.                  |
| Input File Type                   | Determines the format of the input file, which dictates how the processor handles the content. e.g., JSON, CSV, Parquet |
| File Size Limit in Mb             | Sets a maximum file size (in megabytes) that can be read; if a file exceeds this limit, it will not be processed.       |
| Time Interval in Seconds          | Defines a timer interval for re-evaluating the filename to check for updates on file changes.                           |
| Data Output Mode                  | Specifies how the data from the file will be formatted in the output.                                                   |
| CSV Comma                         | Indicates whether to use commas as delimiters in CSV output.                                                            |
| CSV Columns Mode                  | Sets how columns are managed in the CSV output format.                                                                  |
| CSV Customs Columns               | Allows the definition of custom columns for CSV output, providing flexibility in data structuring.                      |

![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/vTsLunQWvJ7ukDma0SkYB_image.png)