terminal_style

What it is

A small helper module for a SPARQL terminal UI that:

• Renders queries, results, and messages using Rich (tables, panels, syntax highlighting).
• Collects interactive user input with basic multiline support.
• Persists command/query history to ~/.sparql_terminal_history on exit.

Public API

Functions:

• set_terminal_title(): Sets the terminal title to “SPARQL Terminal” (Windows via title, Unix-like via escape sequence).
• print_query_result(result): Pretty-prints SPARQL query results (expects an RDFLib SPARQLResult-like object with .vars and iterable rows).
• print_query_error(error): Prints an error in a red Rich panel.
• print_system_message(text): Prints a yellow “System” panel message.
• print_query(query): Displays a SPARQL query with syntax highlighting (sparql, monokai) in a panel.
• clear_screen(): Clears the console (rich.Console.clear()).
• print_welcome_message(): Sets terminal title and prints usage/help text.
• print_divider(): Prints a dim horizontal divider across current console width.
• preinput(): Captures current readline buffer into a module-level current_input.
• get_user_input(): Reads interactive input:
  • Special commands: exit, help, clear (returned lowercase).
  • Multiline: collects lines until:
    • a line ends with ;, or
    • an empty line is entered after content exists.
  • Strips a trailing ; from the final query.
  • On EOFError/KeyboardInterrupt: prints a message and returns "exit".

History persistence:

• save_history(): Writes command_history to ~/.sparql_terminal_history.
• load_history(): Loads command_history from ~/.sparql_terminal_history if present.

Module-level objects/state (used by the API):

• console: rich.console.Console() instance used for all I/O.
• command_history: list of past commands/queries (loaded at import time).
• history_index, current_input: globals (note: history_index is not used in current logic).

Configuration/Dependencies

• Dependencies:
  • rich (Console, Panel, Syntax, Text, Table, ROUNDED)
  • Standard library: os, platform, readline, atexit
• Files:
  • History file path: ~/.sparql_terminal_history
• Import-time side effects:
  • load_history() is called on import.
  • save_history() is registered via atexit.register(...).

Usage

from naas_abi.apps.sparql_terminal import terminal_style as ts
 
ts.print_welcome_message()
 
while True:
    user_text = ts.get_user_input()
    if user_text == "exit":
        break
    if user_text == "clear":
        ts.clear_screen()
        continue
    if user_text == "help":
        ts.print_welcome_message()
        continue
 
    ts.print_query(user_text)
    # Execute query elsewhere and pass results to:
    # ts.print_query_result(result)

Caveats

• get_user_input() relies on rich.Console.input() and readline; history navigation behavior depends on the runtime environment and terminal support.
• History saving/loading silently ignores all exceptions (failures won’t be reported).
• Multiline termination is simplistic: a trailing ; ends input and is removed from the final query string.