Add some documentation to the testing shell scripts

Author: whyscream

test_config_syntax.sh

@@ -1,5 +1,11 @@
 #!/bin/sh
 
+#
+# This script is used to test the config syntax of the 50-filter-postfix.conf file.
+#
+# The configuration file is validated using the logstash --config.test_and_exit command in a docker container.
+#
+
 set -eux
 
 docker run --rm -it \

test_grok_patterns.sh

@@ -1,5 +1,11 @@
 #!/bin/sh
 
+#
+# This script is used to test the grok patterns in the postfix.grok file.
+#
+# The patterns are tested by running the test suite (in test/test.rb and test/*.yaml)
+# against the patterns in the postfix.grok file in a docker container.
+#
 set -eux
 
 DOCKERIMAGE="postfix-grok-patterns-runtests"

test_pipeline.sh

@@ -1,5 +1,12 @@
 #!/bin/sh
 
+#
+# This script is used to test the logstash pipeline configuration.
+#
+# It sets up a logstash pipeline with the postfix configuration,
+# sends a test logline through the pipeline and checks the results.
+#
+
 set -eux
 
 INPUT=$(mktemp tmp.logstash.in.XXXXX)