#### [Examples](../README.md)

## Bashbot webhook example

### Webhook

Bashbot default mode is to poll Telegram server for updates but Telegram offers webhook as a more efficient method to deliver updates.
If your server is reachable from the Internet its possible to use the method described here.

Prerequisite for receiving Telegram unpdates with webhook is a valid SSL certificate, a self signed certificate will not be sufficient.

*Note:* You need at least sudo rights to setup webhook.


#### Setup Apache webhook

Prerequisite: An Apache webserver with a valid SLL certificate chain and php enabled.\
This should work with other webservers also but it's not testet. 

Setup webhook with Apache: 

- install bashbot as described in [Bashbot Installation](../../doc/0_install.md)
- create file `data-bot-bash/webhook-fifo-<botname>` (_\<botname\> as in `botconfig.jssh`_)
- run `sudo bashbot.sh init` to setup bashbot to run as same user as Apache (_e.g. www_)
- go to apache web root and create the directory `telegram/<your_bot_token>` (_<your_bot_token> as `botconfig.jssh`_)
- go into the new directory and copy all files from `examples/webhook` to it
- edit file `BASHBOT_HOME` to contain ithe Bashbot installation directory as first line (_other lines are ignored_)
- execute `php index.php` to test if script has write access to `data-bot-bash/webhook-fifo-<botname>

Calling `https://<yourservername>/telegram/<your_bot_token>/` will execute `index.php`
thus append received data to the file `data-bot-bash/webhook-fifo-<botname>`.
E.g. `https://<yourservername>/telegram/<your_bot_token>/?json={"test":"me"}` will append `{"test":"me"}`.

Now your Server is ready to receive updates from Telegram. 


#### Default webhook processing

This is the testet and supported default method for receiving and processing Telegram updates over webhook.

To enable update processing delete the file `data-bot-bash/webhook-fifo-<botname>` after your webhook is working as described above.
Incoming Telegram updates are now forwarded to the script `bin/process_update.sh` for processing.

On every incoming Telegram update the script is executed, source bashbot.sh and forward the update to Bashbot processing.i
Even it seems overhead to source Bashbot for every update, it's more responsive and create less load than Bashbot polling mode.

Nevertheles there are some limitations compared to polling mode:
 - no startup actions
 - no background* and interactive jobs
 - `addons` and `TIMER_EVENTS` are not working

\* Workaround for background jobs is to execute `./bashbot.sh resumeback` if a new background job was started.

#### Full webhook processing

Full webhook processing use an external script to imitate Bashbot polling mode with webhook.
There is no support for running the script in background, as a service or an other user.

1. Default webook method must work first!
2. run `bashbot.sh init` to setup bashbot to run with your user id
2. Create a named pipe: `mkfifo data-bot-bash/webhook-fifo-botname` and give the web server write access to it
3. Start the script to imitate Bashbot polling mode:\
`bin/process-batch.sh --startbot --watch data-bot-bash/webhook-fifo-<botname>`

The script read updates from given file line by line and forward updates to Bashbot update processing. `--startbot` will run the startup actions
(_e.g. load addons, start TIMER, trigger first run_) and `--watch` will wait for new updates instead of exit on end of file.

To switch back to default processing delete fifo `data-bot-bash/webhook-fifo-<botname>` and kill `bin/process-batch.sh`.

#### Enable webhook on Telegram side

To get updates via webhook your server must be reachable from the internet and you must
instruct Telegram where to deliver updates, this is done by calling bashbot function `set_webhook`.

*Example:*

```bash
bin/any_command.sh set_webhook "https://myserver.com/telegram"
```

instruct Telegram to use the URL `https://myserver.com/telegram/<your_bot_token>/` to deliver updates.
After you enable webhook to deliver Telegram updates it's no more possible to poll updates with `bashbot.sh start`.

To stop delivering of Telegram updates via webhook run `bin/any_command.sh delete_webhook`.

**Important**: Telegram will refuse to deliver updates if your webhook has no valid SSL certificate chain.


#### Bash webhook

A pure bash webhook implementation is not possible without extra software because Telegram delivers
webhook updates only over secure TLS connections with a valid SSL certificate chain.

`socat` looks like a tool to listen for Telegram updates from bash scripts, let's see ...


#### $$VERSION$$ v1.45-dev-58-ga473e25