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README.md

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 # msmtp
 
 send mail from your container  
+this image is intended to be used in a CI piple  
+
+
+## Environment variables
+
+| Variable Name      | Requered | Description | Example
+|--------------------|-----|------------------|--------
+|`SMTP_HOST`         | Yes | The smtp url of your email server | `smtp.gmail.com`
+|`SMTP_PORT`         | no  | The smtp port usually `25`, `465` or `587` *this is the default* | `587`
+|`SMTP_FROM`         | Yes | Your email address | `my_email@gmail.com`
+|`SMTP_USER`         | Yes | Your username for the server<br>usually the same as your email addres or the part before the @ | `my_email`
+|`SMTP_PASSWORD`     | Yes | its where the password go's<br>*the password gets stored in plaintext on the container* | `Hunter22`
+|`EMAIL`             | No  | The "raw" email | Example [here](###-the-second-way)
+|`TO_ADDRESSES`      | Yes | The adress or addresses to send to<br> to send to multiple addresses add `, ` (comma and space) betean each address | `alice@outlook.com, bob@gamil.com`
+|`SUBJECT`           | No | The email subject | `text`
+|`MESSAGE`           | No | The body off the email | `lots of text`
+|`SMTP_AUTH`         | No | enable/disable authentication<br>Valid values are `off` or `on` *this is the default* | `on`
+|`SMTP_TLS`          | No | enable/disable TLS encryption<br>Valid values are `off` or `on` *this is the default* | `on`
+
+### Environment variables files
+it is also posable subsitute the variables [above](##-Environment-variables) with a file  
+to use this simpy take what you normaly use for the variable and put it in a file  
+and make the contents of the `_FILE` variable the path to that file  
+using this way other proccesses could provide the email content  
+all of these are optinal but when uses the overwrite the counterpart variable  
+| Variable Name      | Description |
+|--------------------|-------------|
+|`MSMTP_CONFIG_FILE` | This is the config file msmtp uses<br>this replaces the need for most other Environment variables<br>When you use this only `EMAIL` or `TO_ADDRESSES`, `SUBJECT`, `MESSAGE` are requered<br>to see what the file sould contain have a look at the [Documentation](https://marlam.de/msmtp/msmtp.html#Configuration-files) or a [Example](https://marlam.de/msmtp/msmtprc.txt)
+|`SMTP_HOST_FILE`    |
+|`SMTP_PORT_FILE`    |
+|`SMTP_FROM_FILE`    |
+|`SMTP_USER_FILE`    |
+|`SMTP_PASSWORD_FILE`|
+|`EMAIL_FILE`        |
+
+## Writing the email
+
+There a 2 ways to write the actual email  
+### the first way
+provide the `TO_ADDRESSES` and `SUBJECT` and `MESSAGE` environment variables
+this is a very basic and simple way to write the email  
+
+### the second way
+provide the `EMAIL` environment variable  
+this is a more advanced way to write the email  
+using the `EMAIL` overwrites the `TO_ADDRESSES` and `SUBJECT` and `MESSAGE` environment variables  
+a basic `EMAIL` is formated like below
+```
+To: recipient@gmail.com
+Subject: The subject (followd by a empty line)
+
+This is the first like of the body
+```
+
+## Defaults for popular mail servers
+if its not on the list figger it out yourself *and make a pull request*  
+tip: search for your servers imap clent settings usually it also lists smtp settings
+| Name    | `SMTP_HOST`             | `SMTP_PORT` |
+|---------|-------------------------|-------------|
+| Gmail   | `smtp.gmail.com`        | `587`       |
+| Outlook | `smtp-mail.outlook.com` | `587`       |
+| Yahoo   | `smtp.mail.yahoo.com`   | `587`       |