A simple test script for a web server's If-Modified-Since behavior

if-modified-since-test.sh

#!/bin/bash

set -e

echo "Setting last_mod to before foo is created..."
last_mod=$(date -u +"%a, %d %b %Y %H:%M:%S GMT")
sleep 2

touch foo
function rm_foo {
  rm -f foo
}
trap rm_foo EXIT

echo "Sanity check (should get 200)"
actual=$(curl -si localhost:8000/foo | head -1 | awk '{ print $2 }')
expected="200"
if [ $actual = $expected ]; then
  echo ✅
else
  echo ❌ $actual
fi

echo "Request with old Last-Modified (should get 200)"
actual=$(curl -siH "If-Modified-Since: $last_mod" localhost:8000/foo | head -1 | awk '{ print $2 }')
expected=200
if [ $actual = $expected ]; then
  echo ✅
else
  echo ❌ $actual
fi

last_mod=$(curl -si localhost:8000/foo | grep Last-Modified | sed -e 's/Last-Modified: //')
echo "Request with file's Last-Modified (should get 304)"
actual=$(curl -siH "If-Modified-Since: $last_mod" localhost:8000/foo | head -1 | awk '{ print $2 }')
expected=304
if [ $actual = $expected ]; then
  echo ✅
else
  echo ❌ $actual
fi

echo "Sleeping then updating..."
sleep 2
touch foo

echo "Request updated file with Last-Modified (should get 200)"
actual=$(curl -siH "If-Modified-Since: $last_mod" localhost:8000/foo | head -1 | awk '{ print $2 }')
expected=200
if [ $actual = $expected ]; then
  echo ✅
else
  echo ❌ $actual
fi