Create a file reading tool

Returns a securer::securer_tool() that reads files from specified directories with format detection and size limits.

Usage

read_file_tool(
  allowed_dirs,
  max_file_size = "50MB",
  max_rows = 10000,
  max_calls = NULL
)

Arguments

allowed_dirs

Character vector of directories the tool can read from.

max_file_size

Max file size. Default "50MB". Accepts bytes or string like "10MB".

max_rows

Maximum rows for tabular formats. Default 10000.

max_calls

Maximum invocations. NULL means unlimited.

Value

A securer_tool object.

Details

Supported formats: csv, json, txt, xlsx, parquet, rds. Format is detected automatically from the file extension, or can be specified explicitly via the format argument.

Security measures:

• Path validation: All paths are resolved via base::normalizePath() and checked against allowed_dirs. Symlinks are resolved before the directory check, preventing symlink-based escapes.

• RDS sandboxing: RDS files are deserialized in a separate subprocess via callr, isolating the main process from malicious objects that execute code on load.

• Size limits: Files exceeding max_file_size are rejected before reading.

• Row limits: Tabular formats (csv, xlsx) are capped at max_rows rows.

See also

securer_tool

Other tool factories: calculator_tool(), data_profile_tool(), fetch_url_tool(), plot_tool(), query_sql_tool(), r_help_tool(), write_file_tool()

Examples

# \donttest{
tool <- read_file_tool(
  allowed_dirs = c("/data/reports", "/data/exports"),
  max_file_size = "10MB",
  max_rows = 5000
)
# }