tg-markdown-to-flex 0.3.0

Convert Telegram MarkdownV2 text to LINE Flex Messages

tg-markdown-to-flex

Convert Telegram MarkdownV2 text to LINE Flex Messages.

Available as both a Rust crate and a Python package (via PyO3).

What it does

Takes a string with Telegram MarkdownV2 formatting and produces a LINE Flex Message JSON — a bubble with styled text spans, code blocks, and link buttons.

Formatting mapping

Telegram MarkdownV2	LINE Flex
*bold*	span weight: "bold"
_italic_	span style: "italic"
__underline__	span decoration: "underline"
~strikethrough~	span decoration: "line-through"
`inline code`	span with red color, small size
```code block```	separate text component, red/small
||spoiler||	span with near-white color
[text](url)	link button (see below)

Smart link dedup

By default, links at the end of a line are rendered as a button in the message body (with a separator and grey background), avoiding duplication. Links in the middle of text still get an inline blue/underlined span plus a footer button.

This behavior is configurable — see the options below.

Python

Requires Python 3.13+.

Installation

uv add tg-markdown-to-flex

# or
pip install tg-markdown-to-flex

Usage

import json
from tg_markdown_to_flex import tg_markdown_to_flex

flex_json = tg_markdown_to_flex("Hello *bold* and _italic_ with [a link](https://example.com)")
message = json.loads(flex_json)

# Send via LINE Messaging API
# line_bot_api.push_message(to, FlexMessage(alt_text=message["altText"], contents=message["contents"]))

The function returns a JSON string representing a complete Flex Message (type "flex" with altText and contents).

Options

tg_markdown_to_flex(
    text,
    *,
    standalone_links_as_buttons=True,  # dedup trailing links as body buttons
    decorate_links=True,               # blue/underline styling on inline links
)

Type checking

The package ships with PEP 561 type stubs.

Rust

Installation

[dependencies]
tg-markdown-to-flex = "0.3.0"

Usage

use tg_markdown_to_flex::{tg_markdown_to_flex, tg_markdown_to_flex_json};

// Get a FlexMessage struct
let message = tg_markdown_to_flex("Hello *world*");

// Or get JSON directly
let json = tg_markdown_to_flex_json("Hello *world*");

With options:

use tg_markdown_to_flex::{tg_markdown_to_flex_with_options, ConvertOptions};

let options = ConvertOptions {
    standalone_links_as_buttons: false,
    decorate_links: false,
};
let message = tg_markdown_to_flex_with_options("Hello *world*", &options);

Testing

cargo nextest run

License

MIT