Add automatic tests to the project

Jenkinsfile

@@ -51,7 +51,8 @@ pipeline {
                     steps {
                         script {
                             if(!infra.isTrusted()) {
-                                sh './build.sh ; docker system prune --force --all'
+                                sh 'make tests && make build'
+                                sh 'docker system prune --force --all'
                             }
                         }
                     }

Makefile

@@ -0,0 +1,14 @@
+ROOT:=$(shell dirname $(realpath $(lastword $(MAKEFILE_LIST))))
+IMAGE_NAME:=jenkins4eval/slave
+IMAGE_NAME_AGENT:=jenkins4eval/agent
+
+build:
+	docker build -t ${IMAGE_NAME}:latest -t ${IMAGE_NAME_AGENT}:latest .
+	docker build -t ${IMAGE_NAME}:alpine -t ${IMAGE_NAME_AGENT}:alpine -f Dockerfile-alpine .
+	docker build -t ${IMAGE_NAME}:jdk11  -t ${IMAGE_NAME_AGENT}:jdk11  -f Dockerfile-jdk11  .
+
+.PHONY: tests
+tests:
+	@bats tests/tests.bats
+	@FLAVOR=alpine bats tests/tests.bats
+	@FLAVOR=jdk11 bats tests/tests.bats

tests/test_helpers.bash

@@ -0,0 +1,58 @@
+#!/usr/bin/env bash
+
+set -eu
+
+# check dependencies
+(
+    type docker &>/dev/null || ( echo "docker is not available"; exit 1 )
+)>&2
+
+function printMessage {
+  echo "# ${*}" >&3
+}
+
+# Assert that $1 is the output of a command $2
+function assert {
+    local expected_output
+    local actual_output
+    expected_output="${1}"
+    shift
+    actual_output=$("${@}")
+    if ! [[ "${actual_output}" = "${expected_output}" ]]; then
+        printMessage "Expected: '${expected_output}', actual: '${actual_output}'"
+        false
+    fi
+}
+
+# Retry a command $1 times until it succeeds. Wait $2 seconds between retries.
+function retry {
+    local attempts
+    local delay
+    local i
+    attempts="${1}"
+    shift
+    delay="${1}"
+    shift
+
+    for ((i=0; i < attempts; i++)); do
+        run "${@}"
+        if [[ "${status}" -eq 0 ]]; then
+            return 0
+        fi
+        sleep "${delay}"
+    done
+
+    printMessage "Command '${*}' failed $attempts times. Status: ${status}. Output: ${output}"
+
+    false
+}
+
+function clean_test_container {
+	docker kill "${SLAVE_CONTAINER}" &>/dev/null || :
+	docker rm -fv "${SLAVE_CONTAINER}" &>/dev/null || :
+}
+
+function is_slave_container_running {
+	sleep 1
+	retry 3 1 assert "true" docker inspect -f '{{.State.Running}}' "${SLAVE_CONTAINER}"
+}

tests/tests.bats

@@ -0,0 +1,122 @@
+#!/usr/bin/env bats
+
+DOCKERFILE=Dockerfile
+JDK=8
+SLAVE_IMAGE=jenkins-slave
+SLAVE_CONTAINER=bats-jenkins-slave
+
+if [[ -z "${FLAVOR}" ]]
+then
+  FLAVOR="debian"
+elif [[ "${FLAVOR}" = "jdk11" ]]
+then
+  DOCKERFILE+="-jdk11"
+  JDK=11
+  SLAVE_IMAGE+=":jdk11"
+  SLAVE_CONTAINER+="-jdk11"
+else
+  DOCKERFILE+="-alpine"
+  SLAVE_IMAGE+=":alpine"
+  SLAVE_CONTAINER+="-alpine"
+fi
+
+load test_helpers
+
+clean_test_container
+
+function teardown () {
+  clean_test_container
+}
+
+@test "[${FLAVOR}] build image" {
+  cd "${BATS_TEST_DIRNAME}"/.. || false
+  docker build -t "${SLAVE_IMAGE}" -f "${DOCKERFILE}" .
+}
+
+@test "[${FLAVOR}] checking image metadata" {
+  local VOLUMES_MAP
+  VOLUMES_MAP="$(docker inspect -f '{{.Config.Volumes}}' ${SLAVE_IMAGE})"
+
+  echo "${VOLUMES_MAP}" | grep '/home/jenkins/.jenkins'
+  echo "${VOLUMES_MAP}" | grep '/home/jenkins/agent'
+}
+
+@test "[${FLAVOR}] image has bash and java installed and in the PATH" {
+  docker run -d -it --name "${SLAVE_CONTAINER}" -P "${SLAVE_IMAGE}" /bin/sh
+
+  is_slave_container_running
+
+  run docker exec "${SLAVE_CONTAINER}" which bash
+  [ "${status}" -eq 0 ]
+  run docker exec "${SLAVE_CONTAINER}" bash --version
+  [ "${status}" -eq 0 ]
+  run docker exec "${SLAVE_CONTAINER}" which java
+  [ "${status}" -eq 0 ]
+
+  if [[ "${JDK}" -eq 8 ]]
+  then
+    run docker exec "${SLAVE_CONTAINER}" sh -c "
+    java -version 2>&1 \
+      | grep -o -E '^openjdk version \"[[:digit:]]+\.[[:digit:]]+\.[[:digit:]]+.*\"' \
+      | grep -o -E '\.[[:digit:]]+\.' \
+      | grep -o -E '[[:digit:]]+'
+    "
+  else
+    run docker exec "${SLAVE_CONTAINER}" sh -c "
+    java -version 2>&1 \
+      | grep -o -E '^openjdk version \"[[:digit:]]+\.' \
+      | grep -o -E '\"[[:digit:]]+\.' \
+      | grep -o -E '[[:digit:]]+'
+    "
+  fi
+  [ "${JDK}" = "${lines[0]}" ]
+
+  run docker exec "${SLAVE_CONTAINER}" sh -c "printenv | grep AGENT_WORKDIR"
+  [ "AGENT_WORKDIR=/home/jenkins/agent" = "${output}" ]
+}
+
+@test "[${FLAVOR}] use build args correctly" {
+  cd "${BATS_TEST_DIRNAME}"/.. || false
+
+  local TEST_VERSION="3.36"
+	local TEST_USER="test-user"
+	local TEST_GROUP="test-group"
+	local TEST_UID=2000
+	local TEST_GID=3000
+	local TEST_AGENT_WORKDIR="/home/test-user/something"
+
+  docker build \
+    --build-arg "VERSION=${TEST_VERSION}" \
+    --build-arg "user=${TEST_USER}" \
+    --build-arg "group=${TEST_GROUP}" \
+    --build-arg "uid=${TEST_UID}" \
+    --build-arg "gid=${TEST_GID}" \
+    --build-arg "AGENT_WORKDIR=${TEST_AGENT_WORKDIR}" \
+    -t "${SLAVE_IMAGE}" \
+    -f "${DOCKERFILE}" .
+
+  docker run -d -it --name "${SLAVE_CONTAINER}" -P "${SLAVE_IMAGE}" /bin/sh
+
+  is_slave_container_running
+
+  run docker exec "${SLAVE_CONTAINER}" sh -c "java -cp /usr/share/jenkins/agent.jar hudson.remoting.jnlp.Main -version"
+  [ "${TEST_VERSION}" = "${lines[0]}" ]
+
+  run docker exec "${SLAVE_CONTAINER}" sh -c "id -u -n ${TEST_USER}"
+  [ "${TEST_USER}" = "${lines[0]}" ]
+
+  run docker exec "${SLAVE_CONTAINER}" sh -c "id -g -n ${TEST_USER}"
+  [ "${TEST_GROUP}" = "${lines[0]}" ]
+
+  run docker exec "${SLAVE_CONTAINER}" sh -c "id -u ${TEST_USER}"
+  [ "${TEST_UID}" = "${lines[0]}" ]
+
+  run docker exec "${SLAVE_CONTAINER}" sh -c "id -g ${TEST_USER}"
+  [ "${TEST_GID}" = "${lines[0]}" ]
+
+  run docker exec "${SLAVE_CONTAINER}" sh -c "printenv | grep AGENT_WORKDIR"
+  [ "AGENT_WORKDIR=/home/${TEST_USER}/something" = "${lines[0]}" ]
+
+  run docker exec "${SLAVE_CONTAINER}" sh -c 'stat -c "%U:%G" "${AGENT_WORKDIR}"'
+  [ "${TEST_USER}:${TEST_GROUP}" = "${lines[0]}" ]
+}