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Read

Reads a file from the local filesystem with line numbers and encoding support.

Common Properties​

  • Name - The custom name of the node.
  • Color - The custom color of the node.
  • Delay Before (sec) - Waits in seconds before executing the node.
  • Delay After (sec) - Waits in seconds after executing node.
  • Continue On Error - Automation will continue regardless of any error. The default value is false.

Inputs​

  • File Path - string - Absolute path to the file to read (required).
  • Line Offset - int - Starting line number to read from (1-based, optional).
  • Line Limit - int - Maximum number of lines to read (optional, default: 2000).

Options​

  • Encoding - Character encoding of the file. Options: Auto Detect, UTF-8, UTF-16, Windows-1252, ISO-8859-1 (default: Auto Detect).
  • Max Line Length - Maximum characters per line. Longer lines will be truncated (default: 2000).

Outputs​

  • Content - string - File contents with line numbers in cat -n format.
  • Line Count - int - Total number of lines read.
  • Is Binary - bool - Whether the file appears to be binary.
  • Detected Encoding - string - The detected or used character encoding.
  • File Info - object - File metadata including size, modified time, and permissions.

How It Works​

The Read node reads files from the filesystem and returns formatted content with line numbers. When executed, the node:

  1. Validates the file path is absolute
  2. Checks if the file exists and is accessible
  3. Detects if the file is binary or text
  4. For binary files: Returns base64-encoded content (limited to 10MB)
  5. For text files:
    • Detects or uses the specified encoding
    • Reads lines with optional offset and limit
    • Formats each line with line number (6-digit, tab-separated)
    • Truncates lines exceeding max length
  6. Returns comprehensive file metadata

Requirements​

  • Valid absolute file path
  • Read permissions on the file
  • For text files: Valid encoding (auto-detected or specified)

Error Handling​

The node will return specific errors in the following cases:

  • Missing file path - "File path is required"
  • Relative path - "File path must be absolute"
  • File not found - "File not found: {{path}}"
  • Access denied - "Cannot access file: {{error}}"
  • Directory instead of file - "Path is a directory, not a file"
  • Read errors - "Error reading file: {{error}}"

Usage Examples​

Basic File Reading​

Read the entire file:

File Path: /home/user/documents/data.txt

Read Specific Lines​

Read 100 lines starting from line 50:

File Path: /home/user/logs/application.log
Line Offset: 50
Line Limit: 100

Read with Specific Encoding​

Read a Windows-encoded file:

File Path: /home/user/windows_file.txt
Encoding: Windows-1252

Binary File Handling​

Read an image file (returns base64):

File Path: /home/user/images/photo.jpg

Output: Base64-encoded content with file size information

Usage Notes​

  • The node automatically detects file encoding by checking for BOM (Byte Order Mark)
  • Binary detection checks for null bytes and non-printable characters
  • Line numbers are formatted as 6-digit numbers followed by a tab
  • Lines longer than Max Line Length are truncated with "..." appended
  • Binary files larger than 10MB are truncated with a size note
  • The default limit of 2000 lines prevents memory issues with large files
  • Output format is compatible with standard cat -n format
  • File Info includes: size (bytes), modTime (ISO 8601), permissions (Unix format), name

Common Use Cases​

Code Review​

Read source code files with line numbers for easy reference.

Log Analysis​

Read log files with offset and limit to analyze specific time ranges.

Configuration Validation​

Read configuration files to verify settings.

Binary File Detection​

Check if files are binary before processing.

Encoding Detection​

Auto-detect file encoding for international text files.