markdown2tg

A lightweight Java library that transforms common Markdown into Telegram's MarkdownV2 format for safe and styled message rendering

Features

• Headings are converted to bold text
• Numbered lists are preserved (• item)
• Unordered lists (*, +, -) are converted to Telegram bullets (- item)
• Emphasis (*text* or _text_) is converted to italic
• Strong emphasis (**text** or __text__) is converted to bold
• Inline and block code is supported, including language annotation for code blocks
• Block quotes are supported
• Links and images are converted to Telegram MarkdownV2 format
• All special characters are escaped for Telegram MarkdownV2
• Spaces and parentheses in links are URL-encoded
• Thematic breaks (---, ***, ___) are supported
• Safe conversion for Telegram message rendering

Installation

Note: You need a GitHub personal access token (PAT) with at least read:packages permission to download packages from GitHub. Set it as gpr.key and your GitHub username as gpr.user in your gradle.properties.

In build.gradle:

repositories {
    maven {
        name = "markdown2tg"
        url = uri("https://maven.pkg.github.com/webcane/markdown2tg")
        credentials {
            username = project.findProperty("gpr.user")
            password = project.findProperty("gpr.key")
        }
    }
}

dependencies {
    implementation "cane.brothers:markdown2tg:${version}"
}

Usage

import cane.brothers.tg.md.convert.MarkdownToTelegramConverter;

MarkdownToTelegramConverter c = new MarkdownToTelegramConverter();
String out = c.convert("# Title\n\n*Hello* **world**. [link](https://example.com)");

Links

• CommonMark Specification: https://commonmark.org/
• CommonMark Java library: https://github.com/commonmark/commonmark-java
• Telegram MarkdownV2: https://core.telegram.org/bots/api#markdownv2-style