Question: Requirements on Docker

[sh-at-bergnet-de]

I have written an app with an Excel output. When I use it with DDEV (PHP 8.2, MariaDB 10.6, otherwise default settings) everything works as desired.
However, if I start the app with Docker there are problems opening it in MS Excel. However, 7zip can unzip the file and alternative programs open the file without problems.

The Docker image is based on php:8.2-apache . I suspect an external dependency, so I compared the loaded modules and adjusted some, e.g. bz2, unfortunately without success. In the following list modules that are loaded in DDEV but Docker are not marked with a dot / plus-sign. Maybe someone here has an idea what I need to adjust to make it work?

[PHP Modules]

• apcu
• bcmath
  bz2
• calendar
  core
  ctype
  curl
  date
  dom
• exif
• FFI
  fileinfo
  filter
  ftp
• gd
• gettext
  hash
  iconv
• igbinary
• imagick
  intl
  json
• ldap
  libxml
  mbstring
• memcached
• msgpack
  mysqli
  mysqlnd
  openssl
  pcntl
  pcre
  PDO
  pdo_mysql
• pdo_pgsql
  pdo_sqlite
• pgsql
  Phar
  posix
  random
  readline
• redis
  reflection
  session
• shmop
  SimpleXML
• soap
• sockets
  sodium
  SPL
  sqlite3
  standard
• sysvmsg
• sysvsem
• sysvshm
  tokenizer
• uploadprogress
  xml
  xmlreader
• xmlrpc
  xmlwriter
• xsl
• Zend OPcache
  zip
  zlib

[Zend Modules]

• Zend OPcache

[mk-j]

"if I start the app with Docker there are problems opening it in MS Excel".
An xlsx file is just a zip file. Open your xlsx/zip file in a hex editor or text editor and see if there are any php errors before the PK \x50\x4b\x03\x04 header. Its usually php.ini settings like display_errors=On or a /tmp dir issue that corrupt these files.