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Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>

CHANGELOG.md

@@ -9,7 +9,12 @@ All notable changes to this project will be documented in this file. The format
 ### Updates
 
 - **Tests**:
-  - existing tests were streamlined and simplified, which is a follow-up of [#3732](https://github.com/docker-mailserver/docker-mailserver/pull/3732)
+  - Refactored mail sending ([#3747](https://github.com/docker-mailserver/docker-mailserver/pull/3747)):
+    - This change is a follow-up to [#3732](https://github.com/docker-mailserver/docker-mailserver/pull/3732) from DMS v13.2.
+    - `swaks` version is now the latest from Github releases instead of the Debian package.
+    - `_nc_wrapper`, `_send_mail` and related helpers expect the `.txt` filepath extension again.
+    - `sending.bash` helper methods were refactored to better integrate `swaks` and accommodate different usage contexts.
+    - `test/files/emails/existing/` files were removed similar to previous removal of SMTP auth files as they became redundant with `swaks`.
 - **Internal:**
   - tests: Replace `wc -l` with `grep -c` ([#3752](https://github.com/docker-mailserver/docker-mailserver/pull/3752))
   - Postfix is now configured with `smtputf8_enable = no` in our default `main.cf` config (_instead of during container startup_). ([#3750](https://github.com/docker-mailserver/docker-mailserver/pull/3750))

target/scripts/build/packages.sh

@@ -196,8 +196,9 @@ function _install_utils() {
   curl -sL https://github.com/01mf02/jaq/releases/latest/download/jaq-v1.2.0-x86_64-unknown-linux-musl -o /usr/bin/jaq && chmod +x /usr/bin/jaq
 
   _log 'trace' 'Installing swaks'
-  local SWAKS_RELEASE='swaks-20240103.0'
+  local SWAKS_VERSION='20240103.0'
-  curl -sSfL "https://github.com/jetmore/swaks/releases/download/v20240103.0/${SWAKS_RELEASE}.tar.gz" | tar -xz
+  local SWAKS_RELEASE="swaks-${SWAKS_VERSION}"
+  curl -sSfL "https://github.com/jetmore/swaks/releases/download/v${SWAKS_VERSION}/${SWAKS_RELEASE}.tar.gz" | tar -xz
   mv "${SWAKS_RELEASE}/swaks" /usr/local/bin
   rm -r "${SWAKS_RELEASE}"
 }

test/helper/sending.bash

@@ -7,13 +7,12 @@
 # ! ATTENTION: This file is loaded by `common.sh` - do not load it yourself!
 # ! ATTENTION: This file requires helper functions from `common.sh`!
 
-# Parse the arguments given to `_send_email` and `_send_email_unchecked`
+# Parse the arguments given to `_send_email` and `_send_email_unchecked`.
-# and print the command that is to be exuted in these functions. How these
+# Outputs the `swaks` command to later be executed by the calling function.
-# functions then handle the result of the invocation depends on the function.
 #
 # ## Note
 #
-# This function is internal and should not be used in tests.
+# This is an internal support function, it should not be used directly by tests.
 function __parse_swaks_arguments() {
   [[ -v CONTAINER_NAME ]] || return 1
 
@@ -50,9 +49,9 @@ function __parse_swaks_arguments() {
   done
 
   if [[ ${DATA_WAS_SUPPLIED} -eq 0 ]]; then
-    # Fallback template without implicit `Message-Id` + `X-Mailer` headers:
+    # Fallback template (without the implicit `Message-Id` + `X-Mailer` headers from swaks):
-    # NOTE: It is better to let Postfix generate the `Message-Id` header and append that
+    # NOTE: It is better to let Postfix generate and append the `Message-Id` header itself,
-    #       as it contains the queue ID for tracking logs and is returned to in swaks output.
+    #       as it will contain the Queue ID for tracking in logs (which is also returned in swaks output).
     ADDITIONAL_SWAKS_OPTIONS+=('--data')
     ADDITIONAL_SWAKS_OPTIONS+=("'Date: %DATE%\nTo: %TO_ADDRESS%\nFrom: %FROM_ADDRESS%\nSubject: test %DATE%\n%NEW_HEADERS%\n%BODY%\n'")
   fi
@@ -63,12 +62,14 @@ function __parse_swaks_arguments() {
 # Sends a mail from the container named by the environment variable `CONTAINER_NAME`
 # to the same or another container.
 #
-# To send a custom email, create a file at `test/files/<TEST FILE>`,
+# To send a custom email:
-# and provide `<TEST FILE>` as an argument to this function.
+# 1. Create a file at `test/files/<TEST FILE>`
+# 2. Provide `<TEST FILE>` as an argument to this function.
 #
 # Parameters include all options that one can supply to `swaks` itself.
-# The `--data` parameter expects either, a relative path from `emails/` or
+# The `--data` parameter expects a value of either:
-# "inline" data, e.g., `Date: 1 Jan 2024\nSubject: This is a test`.
+# - A relative path from `test/files/emails/`
+# - An "inline" data string (e.g., `Date: 1 Jan 2024\nSubject: This is a test`)
 #
 # ## Output
 #
@@ -82,10 +83,9 @@ function __parse_swaks_arguments() {
 # This function will send the email in an "asynchronous" fashion,
 # it will return without waiting for the Postfix mail queue to be emptied.
 #
-# This functions performs **no** implicit `assert_success` to check whether
+# This functions performs **no** implicit `assert_success` to check whether the
-# the e-mail transaction was successful. If this is not desirable, use
+# e-mail transaction was successful. If this is not desirable, use `_send_email`.
-# `_send_email`. If you anticipate the sending to succeed, use `_send_email`
+# If you anticipate the sending to succeed, use `_send_email` instead.
-# instead.
 function _send_email_unchecked() {
   local COMMAND_STRING=$(__parse_swaks_arguments "${@}")
   _run_in_container_bash "${COMMAND_STRING}"
@@ -98,12 +98,14 @@ function _send_email_unchecked() {
 # Sends a mail from the container named by the environment variable `CONTAINER_NAME`
 # to the same or another container.
 #
-# To send a custom email, create a file at `test/files/<TEST FILE>`,
+# To send a custom email:
-# and provide `<TEST FILE>` as an argument to this function.
+# 1. Create a file at `test/files/<TEST FILE>`
+# 2. Provide `<TEST FILE>` as an argument to this function.
 #
 # Parameters include all options that one can supply to `swaks` itself.
-# The `--data` parameter expects either, a relative path from `emails/` or
+# The `--data` parameter expects a value of either:
-# "inline" data, e.g., `Date: 1 Jan 2024\nSubject: This is a test`.
+# - A relative path from `test/files/emails/`
+# - An "inline" data string (e.g., `Date: 1 Jan 2024\nSubject: This is a test`)
 #
 # ## Output
 #

test/tests/parallel/set1/spam_virus/rspamd_full.bats

@@ -46,14 +46,14 @@ function setup_file() {
   # We will send 4 emails:
   # 1. The first one should pass just fine
   _send_email_and_get_id MAIL_ID_PASS
-  # 2. The second one should be rejected due to spam (GTube pattern)
+  # 2. The second one should be rejected due to spam (GTUBE pattern)
   _send_email_and_get_id MAIL_ID_SPAM --unchecked \
     --body 'XJS*C4JDBQADN1.NSBN3*2IDNEN*GTUBE-STANDARD-ANTI-UBE-TEST-EMAIL*C.34X'
-  # 3. Te third one should be rejected due to a virus (ClamAV Eicar pattern)
+  # 3. The third one should be rejected due to a virus (ClamAV EICAR pattern)
   # shellcheck disable=SC2016
   _send_email_and_get_id MAIL_ID_VIRUS --unchecked \
     --body 'X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H*'
-  # 4. The fourth one will receive an added header (GTube pattern)
+  # 4. The fourth one will receive an added header (GTUBE pattern)
   _send_email_and_get_id MAIL_ID_HEADER \
     --body 'YJS*C4JDBQADN1.NSBN3*2IDNEN*GTUBE-STANDARD-ANTI-UBE-TEST-EMAIL*C.34X'