[MM-17703] Diff config files (#11898)

Makefile

@@ -1,4 +1,4 @@
-.PHONY: build package run stop run-client run-server stop-client stop-server restart restart-server restart-client start-docker clean-dist clean nuke check-style check-client-style check-server-style check-unit-tests test dist prepare-enteprise run-client-tests setup-run-client-tests cleanup-run-client-tests test-client build-linux build-osx build-windows internal-test-web-client vet run-server-for-web-client-tests
+.PHONY: build package run stop run-client run-server stop-client stop-server restart restart-server restart-client start-docker clean-dist clean nuke check-style check-client-style check-server-style check-unit-tests test dist prepare-enteprise run-client-tests setup-run-client-tests cleanup-run-client-tests test-client build-linux build-osx build-windows internal-test-web-client vet run-server-for-web-client-tests diff-config
 
 ROOT := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
 
@@ -410,6 +410,9 @@ config-reset: ## Resets the config/config.json file to the default.
 	rm -f config/config.json
 	OUTPUT_CONFIG=$(PWD)/config/config.json go generate ./config
 
+diff-config: ## Compares default configuration between two mattermost versions
+	@./scripts/diff-config.sh
+
 clean: stop-docker ## Clean up everything except persistant server data.
 	@echo Cleaning
 

scripts/diff-config.sh

@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+
+jq_cmd=jq
+[[ $(type -P "$jq_cmd") ]] || { 
+	echo "'$jq_cmd' command line JSON processor not found";
+	echo "Please install on linux with 'sudo apt-get install jq'"
+	echo "Please install on mac with 'brew install jq'"
+	exit 1; 
+}
+
+if [ -z "$FROM" ]
+then
+  echo "Missing FROM version. Usage: make diff-config FROM=1.1.1 TO=2.2.2"
+  exit 1
+fi
+
+if [ -z "$TO" ]
+then
+  echo "Missing TO version. Usage: make diff-config FROM=1.1.1 TO=2.2.2"
+  exit 1
+fi
+
+# Returns the config file for a specific release
+fetch_config() {
+  local url="https://releases.mattermost.com/$1/mattermost-$1-linux-amd64.tar.gz"
+  curl -sf "$url" | tar -xzOf - mattermost/config/config.json | jq -S .
+}
+
+echo Fetching config files
+from_config="$(fetch_config "$FROM")"
+if [ -z "$from_config" ]
+then
+  echo Invalid version "$FROM"
+  exit 1
+fi
+
+to_config=$(fetch_config "$TO")
+if [ -z "$to_config" ]
+then
+  echo Invalid version "$TO"
+  exit 1
+fi
+
+echo Comparing config files
+diff -y <(echo "$from_config") <(echo "$to_config")
+
+# We ignore exits with 1 since it just means there's a difference, which is fine for us.
+diff_exit=$?
+if [ $diff_exit -eq 1 ]; then
+  exit 0
+else
+  exit $diff_exit
+fi