refactor: add helper scripts

jenkins/check_package_changed.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+# Based on this post:
+# https://engineering.brigad.co/only-deploy-services-impacted-by-changes-in-a-mono-repository-18f54b8ac109
+
+APP=$1
+# Jenkins should provide these in the environment by default
+GIT_COMMIT=$2
+GIT_PREVIOUS_COMMIT=$3
+ROOT_FILES_AND_FOLDERS=${4:-"package.json" "yarn.lock" ".dockerignore" "docker" "jenkins"}
+
+function join_by { local IFS="$1"; shift; echo "$*"; }
+
+function package_changed { git diff --name-only "$COMMIT_RANGE" | grep -qE "^packages/$1/" && echo true || echo false; }
+
+COMMIT_RANGE="$GIT_PREVIOUS_COMMIT...$GIT_COMMIT"
+ROOT_FILES_AND_FOLDERS_ARRAY=($ROOT_FILES_AND_FOLDERS)
+ROOT_FILES_AND_FOLDERS_JOINED=$(join_by "|" ${ROOT_FILES_AND_FOLDERS_ARRAY[*]})
+
+ROOT_FILES_CHANGED=$(git diff --name-only "$COMMIT_RANGE" | grep -qE "^($ROOT_FILES_AND_FOLDERS_JOINED)" && echo true || echo false)
+IS_FORCE_BUILD=$(git log --oneline "$COMMIT_RANGE" | grep -qE "ci: force" && echo true || echo false)
+APP_FILES_CHANGED=$(package_changed ${APP})
+
+($IS_FORCE_BUILD || $ROOT_FILES_CHANGED || $APP_FILES_CHANGED) && echo 0 || echo 1

jenkins/hash_build_properties.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+
+# Outputs to the stdout a deterministically generated integer in the range 0-4095. The integer is generated using the
+# input strings and SHA1.
+# Usage: hash_build_properties.sh <branch> <build_number>
+# Inputs:
+#   - branch:       the branch being build
+#   - build_number  the incrementing number of the build
+
+BRANCH=$1
+BUILD_NUMBER=$2
+
+STRING_TO_HASH="$BRANCH-$BUILD_NUMBER"
+SHA1_SUM_HEX=$(sha1sum <<<"$STRING_TO_HASH")
+SHA1_TRUNCATED_HEX=$(cut -c1-3 <<<"$SHA1_SUM_HEX")
+HASHED_STRING=$((0x${SHA1_TRUNCATED_HEX}))
+
+echo "$HASHED_STRING"

jenkins/map_to_thousand.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+INTEGER_TO_MAP=$1
+
+echo $(( INTEGER_TO_MAP * 999 / 4095 ))