mail2telegram

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Use Telegram Bot to get your temporary email..

This is a Telegram Bot based on Cloudflare Email Routing Worker, which can convert emails into Telegram messages. You can forward emails from recipients with any prefix to the Bot, and then a temporary mailbox Bot with an infinite address will be created.

Click to view the demo.

Installation

1. Deploy Workers

1.1 Deploy via Command Line

Clone the repository:

git clone git@github.com:TBXark/mail2telegram.git
Copy the configuration template and modify it with your own Telegram configuration:

cp wrangler.example.toml wrangler.toml
Deploy

yarn & yarn pub

1.2 Deploy via Copy and Paste

If you don't want to deploy using the command line and prefer to copy and paste, you can use the precompiled version > index.js
When deploying via copy and paste, you need to manually set environment variables in the project's configuration page.
To generate a whitelist/blacklist of regular expressions as a JSON array string, you can use this small tool which also includes some demos: regexs2jsArray

2. Configure Cloudflare Email Routing

Follow the official tutorial to configure Cloudflare Email Routing.
Configure routing by changing the action of Catch-all address in Email Routing - Routing Rules to Send to a Worker:mail2telegram. Forward all remaining emails to this worker.
If you set Catch-all address as workers, you won't be able to forward all remaining emails to your own email. If you need to backup emails, simply fill in your backup email in the FORWARD_LIST environment variable of the worker.

3. Binding a Telegram Webhook

Call https://project_name.user_name.workers.dev/init to bind the Webhook, check the return result to confirm the binding status.

Configuration

KEY	Description
TELEGRAM_ID	Your Telegram ID, pure numbers can be obtained through the `/id` command.
TELEGRAM_TOKEN	Telegram Bot Token
DOMAIN	Workers domain name, example: `project_name.user_name.workers.dev`
FORWARD_LIST	Backup emails, can be forwarded to your own email for backup, leave blank if not forwarding, multiple values can be separated by `,`
WHITE_LIST	Sender whitelist, an array of regular expressions converted to a string, example: `[\".*@10086\\\\.cn\"]`
BLOCK_LIST	Sender blacklist, an array of regular expressions converted to a string
MAIL_TTL	Email cache retention time in seconds, default is one day. After expiration, emails will no longer be previewable. Please make sure to back them up.
OPENAI_API_KEY	OpenAI API Key, Used for summarizing email content. If not filled out, the "Summary" button will not appear.
OPENAI_COMPLETIONS_API	Customizable API, default value is `https://api.openai.com/v1/chat/completions`
OPENAI_CHAT_MODEL	Customizable model, default value is `gpt-3.5-turbo`
SUMMARY_TARGET_LANG	The language for customizing the summary, with a default value of `english`
GUARDIAN_MODE	Guard mode, default off, if you want to enable it, fill in `true`.
MAX_EMAIL_SIZE	Maximum email size in bytes, emails exceeding this size will be processed according to `MAX_EMAIL_SIZE_POLICY`. The main purpose is to prevent the worker function from timing out due to too large attachments. Default is 512*1024.
MAX_EMAIL_SIZE_POLICY	The available values are `unhandled`, `truncate` and `continute`. `unhandled` means return the headers without parsing the message body, `truncate` means truncate the message body and only parse the allowed size, `continute` means continue to process the message regardless of the size limit. The default is `truncate`. This policy only affects Telegram push messages, not email forwarding.
DB	Bind `KV Namespace Bindings` database to worker with the name `DB`.

WHITE_LIST and BLOCK_LIST take effect on both recipients and senders at the same time, with WHITE_LIST having a higher priority than BLOCK_LIST.

The email address in FORWARD_LIST should be added to Cloudflare Dashboard - Email Routing - Destination addresses after authentication in order to receive emails.

Usage

The default message structure is as follows.

[Subject]

-----------
From : [sender]
To: [recipient]

(Preview)(Summary)(Text)(HTML)

When the email forwarding notification is sent to Telegram, only the title, sender, recipient, and four buttons are included.

Using Preview allows you to directly preview the plain text mode of the email in the bot. However, there is a limit of 4096 characters. If it exceeds 4096 characters, you can use TEXT or HTML to view the complete email. Below the preview message, there is a Back button that can be clicked to close the preview.

When you configure OPENAI_API_KEY, a Summary button will appear so that you can summarize the content of the email. Below the summary message, there is a Back button that can be clicked to close the summary.

Using TEXT, you can see plain text emails; using HTML, you can see rich-text emails. However, they may contain certain scripts or other tracking links. It is recommended to use rich-text mode only when necessary or when confirming that there are no issues with its source.

For security reasons, when exceeding the mail cache retention time (MAIL_TTL), links opened by buttons cannot be accessed. You can modify environment variables yourself to adjust expiration time.

This Bot does not support attachments. If you need attachment support, you can combine it with my another project testmail-viewer and forward emails to your testmail using FORWARD_LIST. This way, you can download your attachments using testmail-viewer.

Due to the limitation of Workers, if the email size (especially the attachment size) is too large, it will cause function timeout. At this time, Workers will retry multiple times, which may result in receiving multiple notifications and backup emails. Moreover, there is a limit on the number of retries. Once exceeded, no further retries will be made. This may lead to your email being lost. Therefore, it is recommended that you fill in your backup email in FORWARD_LIST, so that even if your email is lost, you can find it in your backup mailbox. If you frequently encounter this problem, you can try enabling Guardian Mode (GUARDIAN_MODE), which will record the operations already performed and not execute them again during the next retry. This reduces interference from duplicate messages and increases the success rate of workers. However, this operation consumes more KV write operations, so it is recommended to enable it when necessary.

License

mail2telegram is released under the MIT license. See LICENSE for details.

TBXark / mail2telegram