Reddit-Telegram Forwarder

Spring Boot-based Java application to forward Reddit posts to Telegram channel.

Requirements

• Java 21
• Maven
• Reddit profile
• Telegram profile
• Telegram channel
• A chat connected to your Telegram channel

Quickstart

1. Go to https://www.reddit.com/prefs/apps and create an app.

   • Application type must be script.

     

2. Create Telegram Bot. You'll need a bot token.
   • How Do I Create a Bot?
3. Get the app.
   • Clone and build the project:

     git clone https://github.com/yvasyliev/reddit-telegram-repeater.git
     mvn clean package -Dmaven.test.skip
     cd target

   • Or download executable JAR from the latest release.
4. Run the app:

   java -jar reddit-telegram-forwarder-3.2.7.jar \
   --reddit.client.id=${REDDIT_CLIENT_ID} \
   --reddit.client.secret=${REDDIT_CLIENT_SECRET} \
   --reddit.password=${REDDIT_PASSWORD} \
   --reddit.subreddit=${SUBBREDDIT_NAME} \
   --reddit.username=${REDDIT_USERNAME} \
   --telegram.admin.id=${TELEGRAM_ADMIN_ID} \
   --telegram.bot.token=${TELEGRAM_BOT_TOKEN} \
   --telegram.bot.username=${TELEGRAM_BOT_USERNAME} \
   --telegram.channel.id=${TELEGRAM_CHANNEL_ID} \
   --telegram.chat.id=${TELEGRAM_CHAT_ID}

   • Don't forget to replace ${...} placeholders with correct values.

How it works

This a console application built with Spring Boot (not Web!). There is a method ScheduledPostManager#shareNewPosts annotated with @Scheduled. This method retrieves subreddit new posts using Reddit API and forwards them to Telegram channel using Telegram Bots API. By default, shareNewPosts() is invoked once per minute, and it can be configured by environment variables (see Application variables).

If post author is in block list or the post is marked as NSFW, the post will be sent to admin for validation. Admin can either accept or reject posts.

Block list is stored in SQLite database. All database configs and management are handled automatically by Spring Boot Data. No user actions required.

Additionally, this application runs a Long Polling Bot that helps you with application management. The bot can accept suggested user posts (see Bot commands).

Application variables

As you noticed, the application relies on a set of variables. Since it's a Spring Boot project, these variables can be passed as command line arguments (see Quickstart), defined in application.properties or set globally as environment variables (see Spring Boot Docs for more details).

Variable	Required	Default value	Description	Example
delayed.blocking.executor.delay.in.seconds	false	20	Delay in seconds used to postpone sending messages in order to avoid "too many requests" errors in Telegram.	20
http.request.timeout.in.minutes	false	2	Timeout in minutes applied to Reddit API call.	5
reddit.authors.blocked.by.default	false	false	true - check Reddit autor against Block list. false - ignore Block list and ask admin to validate every post.	true
reddit.client.id	true	-	Reddit client_id.	pW134F0XNuueG4W78x9uGA
reddit.client.secret	true	-	Reddit client secret.	fsdT6VkTgf1WMfSW6Pd5t4DRvfVueB
reddit.password	true	-	Reddit profile password.	ETD1fqx%cfk6odj#boj
reddit.subreddit	true	-	Subreddit name without r/ prefix.	cats
reddit.username	true	-	Reddit profile username.	RedditProfileUsername000
telegram.admin.id	true	-	Telegram user ID (Telegram channel admin ID). Bot will send error logs directly to user. How to find your User ID in Telegram?	280531210
telegram.bot.username	true	-	Telegram bot username.	SubredditForwarderBot
telegram.bot.token	true	-	Telegram bot token.	4336854599:BBFqVLRq9ixVdxORFWQgaSywzCfRo5-tBus
telegram.channel.id	true	-	Telegram channel ID. Subreddit posts will be sent to this channel. How to get the channel ID	-1001572613876 or @SubredditPostChannel
telegram.chat.id	true	-	The ID of the chat where users can leave comments under posts. Bot will send additional photos to this chat if orginal subreddit post contains more than 10 images. How to get chat ID	-1003121089009 or @SubbredditPostChannelChat
telegram.schedule.posting.delay.in.minutes	false	1	How often (in minutes) the application should scan subreddit for new posts.	5
telegram.schedule.posting.enabled	false	true	Should application start forwarding right after startup or not. Can be paused/resumed via Bot commands.	false

Bot commands

There are two types of commands:

• user - available for all users;
• admin - available for admin only.

Command	Type	Description
/blockauthor	admin	Add Reddit user to Block list.
/cancel	user	Cancel current command.
/contactadmin	user	Send message to admin.
/done	user	Same as /cancel.
/getblocked	admin	Show block list.
/help	user	Show list of commands.
/pauseposting	admin	Pause posts forwarding.
/resumeposting	admin	Resume posts forwarding.
/start	user	Same as /help.
/stop	admin	Completely stop the application. You can start it again by executing java -jar .... It takes up to ~30 seconds to stop all the processes. Some exceptions can be thrown because of interrupted threads or closed application context. It's fine to ignore them.
/suggestpost	user	Suggest a post to channel. The post will be sent to admin for validation.
/unblockauthor	admin	Remove Reddit user from block list.