3. Change to directory ```telegram-bot.bash```, run ```./bashbot.sh init``` and follow the instructions. At this stage you are asked for your Bots token given by botfather.
All Commands for the Bot are in the ```commands.sh``` file (this should ease upgrades of the bot core). Here you find some examples how to process messages and send out text.
Once you're done editing start the Bot with ```./bashbot.sh start```.
If some thing doesn't work as it should, debug with ```bash -x bashbot.sh```. To stop the Bot run ```./bashbot.sh kill```
To use the functions provided in this script in other scripts simply source bashbot: ```source bashbot.sh```
To send images, videos, voice files, photos etc. use the ```send_photo``` function (remember to change the safety Regex @ line 14 of command.sh to allow sending files only from certain directories):
Allowed values: typing for text messages, upload_photo for photos, record_video or upload_video for videos, record_audio or upload_audio for audio files, upload_document for general files, find_location for locations.
To create interactive chats, write (or edit the question script) a normal bash (or C or python) script, chmod +x it and then change the argument of the startproc function to match the command you usually use to start the script.
The text that the script will output will be sent in real time to the user, and all user input will be sent to the script (as long as it's running or until the user kills it with /cancel).
To open up a keyboard in an interactive script, print out the keyboard layout in the following way:
A background job is similar to an interactive chat, but runs in the background and does only output massages instead of processing input from the user. In contrast to interactive chats it's possible to run multiple background jobs. To create a background job write a script or edit the notify script and use the funtion ```background``` to start it:
Note: Background Jobs run independent from main bot and continue running until your script exits or you stop if from your Bot. Backgound Jobs will continue running if your Bot is stoped (kill)!.
The following commands allows users to interact with your bot via *inline queries*.
In order to enable **inline mode**, send `/setinline` command to [@BotFather](https://telegram.me/botfather) and provide the placeholder text that the user will see in the input field after typing your bot’s name.
To send videos from a website through an *inline query*:
```
answer_inline_query "$iQUERY_ID" "video" "valid video url" "Select one mime type: text/html or video/mp4" "URL of the thumbnail" "Title for the result"
```
To send photos stored in Telegram servers through an *inline query*:
```
answer_inline_query "$iQUERY_ID" "cached_photo" "identifier for the photo"
```
To send gifs stored in Telegram servers through an *inline query*:
```
answer_inline_query "$iQUERY_ID" "cached_gif" "identifier for the gif"
```
To send mpeg4 gifs stored in Telegram servers through an *inline query*:
```
answer_inline_query "$iQUERY_ID" "cached_mpeg4_gif" "identifier for the gif"
```
To send stickers through an *inline query*:
```
answer_inline_query "$iQUERY_ID" "cached_sticker" "identifier for the sticker"
```UTF-8``` is a variable length encoding of Unicode. UTF-8 is recommended as the default encoding in JSON, XML and HTML, also Telegram make use of it.
The first 128 characters are regular ASCII, so it's a superset of and compatible with ASCII environments. The next 1,920 characters need
two bytes for encoding and covers almost all ```Latin``` alphabets, also ```Greek```, ```Cyrillic```,
```Hebrew```, ```Arabic``` and more. See [Wikipedia](https://en.wikipedia.org/wiki/UTF-8) for more deatils.
Telegram send Messages with all characters not fitting in one byte (256 bit) escaped as sequences of ```\uxxxx``` to be regular one byte ASCII (incl. iso-xxx-x), e.g. Emoticons and Arabic characters.
E.g. the Emoticons ``` 😁 😘 ❤️ 😊 👍 ``` are encoded as:
'\uXXXX' and '\UXXXXXXXX' escaped endocings are supported by zsh, bash, ksh93, mksh and FreeBSD sh, GNU 'printf' and GNU 'echo -e', see [this Stackexchange Answer](https://unix.stackexchange.com/questions/252286/how-to-convert-an-emoticon-specified-by-a-uxxxxx-code-to-utf-8/252295#252295) for more information.
Bashbot is desingned to run manually by the user who installed it. Nevertheless it's possible to run it by an other user-ID, as a system service or sceduled from cron. This is onyl recommended for experiend linux users.
- If you are running bashbot with your user-ID, copy the examples lines to your crontab and remove username ```nobody```.
- if you run bashbot as an other user or a system service edit ```bashbot.cron``` to fit your needs and replace username````nobody``` with the username you want to run bashbot. copy the modified file to ```/etc/cron.d/bashbot```
## Security Considerations
Running a Telegram Bot means you are conneted to the public, you never know whats send to your Bot.
Bash scripts in general are not designed to be bullet proof, so consider this Bot as a proof of concept. More concret examples of security problems is bash's 'quoting hell' and globbing. [Implications of wrong quoting](https://unix.stackexchange.com/questions/171346/security-implications-of-forgetting-to-quote-a-variable-in-bash-posix-shells)
Whenever you are processing input from outside your bot you should disable globbing (set -f) and carefully quote everthing.
### Run your Bot as a restricted user
Every file your bot can write is in danger to be overwritten/deleted, In case of bad handling of user input every file your Bot can read is in danger of being disclosed.
Never run your Bot as root, this is the most dangerous you can do! Usually the user 'nobody' has almost no rigths on Unix/Linux systems. See Expert use on how to run your Bot as an other user.
### Secure your Bot installation
Everyone who can read your Bot files can extract your Bots data. Especially your Bot Token in ```token``` must be protected against other users. No one exept you should have write access to the Bot files. The Bot itself need write access to ```count``` and ```tmp-bot-bash``` only, all other files should be write protected.
Runing ```./bashbot init``` sets the Bot permissions to reasonable default values as a starting point.
### Is this Bot insecure?
No - its not more or less insecure as any other Bot written in any other language. But you should know about the implications ...