spring-boot-demo/profiles-and-config/scripts/env.sh

#!/usr/bin/env bash
# Shared environment. Point JAVA_HOME at a JDK 25 (or newer) installation.
: "${JAVA_HOME:?set JAVA_HOME to a JDK 25+ installation}"
export PATH="$JAVA_HOME/bin:$PATH"
MVN="${MVN:-mvn}"
JAR="target/profiles-and-config-1.0.0.jar"
APP_MAIN="com.ankurm.profiles.ProfilesApplication"
APP_PORT="${APP_PORT:-8080}"

# Strip environment noise that is an artefact of the machine, not of Spring:
# the JVM prints a JAVA_TOOL_OPTIONS banner to stderr on every launch when a proxy
# truststore is configured, and it would otherwise end up in every committed transcript.
clean() { grep -v "Picked up JAVA_TOOL_OPTIONS" | grep -v "^OpenJDK 64-Bit Server VM warning"; }

# Start the demo jar detached, record its PID, and block until it answers.
# Extra arguments are passed to the application. Environment variables for the run are
# passed by setting them on the call: `APP_ENV="A=1 B=2" start_app --spring.profiles.active=x`
start_app() {
  stop_app
  mkdir -p target
  # Deliberately NOT setsid: setsid forks when it is not already a process-group leader,
  # so $! would be the PID of a process that exits immediately and the JVM would survive
  # every later stop_app. A surviving JVM keeps the port, the next scenario fails to bind,
  # and curl answers from the previous scenario -- which reads exactly like the
  # configuration change under test having had no effect. Three wrong findings in this
  # repository came from that before it was tracked down.
  if [ -n "${APP_ENV:-}" ]; then
    # shellcheck disable=SC2086
    env $APP_ENV nohup java -jar "$JAR" "$@" > /tmp/profiles-demo.log 2>&1 < /dev/null &
  else
    nohup java -jar "$JAR" "$@" > /tmp/profiles-demo.log 2>&1 < /dev/null &
  fi
  echo $! > target/app.pid
  for _ in $(seq 1 60); do
    curl -s -o /dev/null "http://127.0.0.1:${APP_PORT}/precedence" 2>/dev/null && return 0
    kill -0 "$(cat target/app.pid)" 2>/dev/null || { echo "JVM exited during startup:"
      tail -20 /tmp/profiles-demo.log; return 1; }
    sleep 1
  done
  echo "application did not answer"; tail -20 /tmp/profiles-demo.log; return 1
}

# Stop it by recorded PID. Never by pattern: `ps | grep <jar name>` also matches the shell
# running the script, because the jar name is on that shell's own command line.
stop_app() {
  if [ -f target/app.pid ]; then
    pid=$(cat target/app.pid)
    if [ -n "$pid" ] && grep -qa "profiles-and-config" "/proc/$pid/cmdline" 2>/dev/null; then
      kill -9 "$pid" 2>/dev/null || true
      wait "$pid" 2>/dev/null || true      # reap, so bash prints no "Killed" notice
    fi
    rm -f target/app.pid
  fi
  for _ in $(seq 1 40); do
    if ! (exec 3<>/dev/tcp/127.0.0.1/"${APP_PORT:-8080}") 2>/dev/null; then break; fi
    sleep 0.25
  done
  exec 3<&- 2>/dev/null || true
}

# Print the precedence report for one property, compactly.
report() {
  curl -s "http://127.0.0.1:${APP_PORT}/precedence?name=$1" | python3 -c '
import json,sys
d=json.load(sys.stdin)
print("  active profiles :", ", ".join(d["activeProfiles"]) or "(none)")
print("  effective value :", d["effectiveValue"])
for h in d["holders"]:
    src=h["source"]
    for noisy,short in (("Config resource \x27class path resource [","file "),
                        ("\x27 via location \x27optional:classpath:/\x27}","")):
        src=src.replace(noisy,short)
    src=src.replace("OriginTrackedMapPropertySource {name=","").replace("]","")
    print("    %d. %-34s <- %s" % (h["rank"], h["value"], src.strip()))
print("  holders that lost:", d["shadowedCount"])'
}