feat: Add message_size_limit option (#86)

* feat: Add MESSAGE_SIZE_LIMIT configuration option (PR #86)

.env.example

@@ -37,3 +37,6 @@
 
 # Optional: This will disable (no) or enable (yes) the use of SMTPUTF8
 #SMTPUTF8_ENABLE=no
+
+# Optional: This will use allow you to set a custom $message_size_limit value. Default is 10240000.
+#MESSAGE_SIZE_LIMIT=

.github/ISSUE_TEMPLATE/bug_report.md

@@ -6,12 +6,14 @@ labels: ''
 assignees: ''
 
 ---
-
+<!-- BEFORE SUBMITTING YOUR PR, PLEASE REMOVE THIS TEXT -->
+<!-- REMOVE START -->
 **Reporting a bug**
 
 First of all, this is **not** a problem reporting forum, only report if you are pretty sure what you are experiencing is a bug with this image, not a configuration issue, for that you can use the [Github discussions section](https://github.com/juanluisbaptiste/docker-postfix/discussions) and we will do our best to help you to figure out what's going on with your setup.
 
 Also be sure you are using the latest image by doing _docker pull juanluisbaptiste/postfix:latest_.
+<!-- REMOVE END -->
 
 **Please include the contents of:**
 

.github/pull_request_template.md

@@ -1,10 +1,13 @@
+<!-- BEFORE SUBMITTING YOUR PR, PLEASE REMOVE THIS TEXT -->
+<!-- REMOVE START -->
 # Creating a Pull Request
 
 We use github actions to do automatic [semantic versioning](https://github.com/semantic-release/semantic-release), so please use the following nomenclature for the commit message according to the type of change:
 
 * Prefix with `feat:`, and it will trigger a minor version bump. 
-* Prefix with `fix`:, and it will trigger a patch version bump. 
+* Prefix with `fix:`, and it will trigger a patch version bump.
 * Prefix with `BREAKING CHANGE:`, and it will trigger a major version bump.
+<!-- REMOVE END -->
 
 ## Description of the change
 <!--Please be very clear on the intention of the modifications included in the pull request.-->

README.md

@@ -83,6 +83,8 @@ The following env variable(s) are optional.
 
 * `SMTPUTF8_ENABLE` This will enable (default) or disable support for SMTPUTF8. Valid values are `no` to disable and `yes` to enable. Not setting this variable will use the postfix default, which is `yes`.
 
+* `MESSAGE_SIZE_LIMIT` This will change the default limit of 10240000 bytes (10MB).
+
 To use this container from anywhere, the 25 port or the one specified by `SMTP_PORT` needs to be exposed to the docker host server:
 
     docker run -d --name postfix -p "25:25"  \

run.sh

@@ -99,6 +99,12 @@ if [ ! -z "${OVERWRITE_FROM}" ]; then
   echo "Setting configuration option OVERWRITE_FROM with value: ${OVERWRITE_FROM}"
 fi
 
+# Set message_size_limit
+if [ ! -z "${MESSAGE_SIZE_LIMIT}" ]; then
+  postconf -e "message_size_limit = ${MESSAGE_SIZE_LIMIT}"
+  echo "Setting configuration option message_size_limit with value: ${MESSAGE_SIZE_LIMIT}"
+fi
+
 #Start services
 
 # If host mounting /var/spool/postfix, we need to delete old pid file before