I tried to install MediaWiki-Docker on Debian 10 (buster), but failed.
* VM with Debian 10 (buster), with a basic install, running on my machine at home
```
sudo apt install docker-composer
sudo adduser liw docker
sudo reboot
```
log in again
```
git clone --depth=1 https://gerrit.wikimedia.org/r/mediawiki/core.git mediawiki
cd mediawiki
```
* create `.env` by copy-pasting from `DEVELOPERS.md` and adding the two
extra lines
```
MW_DOCKER_PORT=8080
MW_SCRIPT_PATH=/
MW_SERVER=http://localhost:8080
MEDIAWIKI_USER=Admin
MEDIAWIKI_PASSWORD=dockerpass
XDEBUG_CONFIG=''
MW_DOCKER_UID=1000
MW_DOCKER_GID=1000
```
* create `docker-compose-override.yml` by copy-pasting from `DEVELOPERS.md`
* tried to `docker-compose up`:
```
liw@playground:~/mediawiki$ docker-compose up -d
ERROR: Version in "./docker-compose.yml" is unsupported. You might be seeing this error because you're using the wrong Compose file version. Either specify a supported version (e.g "2.2" or "3.3") and place your service definitions under the `services` key, or omit the `version` key and place your service definitions at the root of the file to use version 1.
For more on the Compose file format versions, see https://docs.docker.com/compose/compose-file/
liw@playground:~/mediawiki$
```
* changed version in `docker-compose.yml` to `3.3`
* `docker-compose up -d` again, failed due to downloading problem
* `docker-compose up -d` again, finished without errors
* `docker-compose exec mediawiki composer update`
* `docker-compose exec mediawiki /bin/bash /docker/install.sh`
* got message
`docker-compose exec mediawiki /bin/bash /docker/install.sh`that wiki is ready on localhost:8080
```
liw@playground:~/mediawiki$ curl http://localhost:8080
<!DOCTYPE html>
<html><head><title>MediaWiki</title><style>body { font-family: sans-serif; margin: 0; padding: 0.5em 2em; }</style></head><body><h1>Sorry! This site is experiencing technical difficulties.</h1><p>Try waiting a few minutes and reloading.</p><p><small>(<span dir="ltr">Cannot access the database: Unknown error (localhost)</span>)</small></p><p>Backtrace:</p><pre>#0 /var/www/html/includes/libs/rdbms/loadbalancer/LoadBalancer.php(934): Wikimedia\Rdbms\LoadBalancer->reportConnectionError()
#1 /var/www/html/includes/libs/rdbms/loadbalancer/LoadBalancer.php(901): Wikimedia\Rdbms\LoadBalancer->getServerConnection(0, 'my_wiki', 0)
#2 /var/www/html/includes/libs/rdbms/loadbalancer/LoadBalancer.php(1046): Wikimedia\Rdbms\LoadBalancer->getConnection(-1, Array, 'my_wiki', 0)
#3 /var/www/html/includes/GlobalFunctions.php(2464): Wikimedia\Rdbms\LoadBalancer->getMaintenanceConnectionRef(-1, 'api', 'my_wiki')
#4 /var/www/html/includes/cache/MessageCache.php(485): wfGetDB(-1, 'api')
#5 /var/www/html/includes/cache/MessageCache.php(440): MessageCache->loadFromDB('en', NULL)
#6 /var/www/html/includes/cache/MessageCache.php(363): MessageCache->loadFromDBWithLock('en', Array, NULL)
#7 /var/www/html/includes/cache/MessageCache.php(1083): MessageCache->load('en')
#8 /var/www/html/includes/cache/MessageCache.php(1010): MessageCache->getMsgFromNamespace('Mainpage', 'en')
#9 /var/www/html/includes/cache/MessageCache.php(980): MessageCache->getMessageForLang(Object(LanguageEn), 'mainpage', true, Array)
#10 /var/www/html/includes/cache/MessageCache.php(922): MessageCache->getMessageFromFallbackChain(Object(LanguageEn), 'mainpage', true)
#11 /var/www/html/includes/language/Message.php(1305): MessageCache->get('mainpage', true, Object(LanguageEn))
#12 /var/www/html/includes/language/Message.php(860): Message->fetchMessage()
#13 /var/www/html/includes/language/Message.php(952): Message->toString('text')
#14 /var/www/html/includes/Title.php(664): Message->text()
#15 /var/www/html/includes/MediaWiki.php(122): Title::newMainPage()
#16 /var/www/html/includes/MediaWiki.php(142): MediaWiki->parseTitle()
#17 /var/www/html/includes/MediaWiki.php(889): MediaWiki->getTitle()
#18 /var/www/html/includes/MediaWiki.php(535): MediaWiki->main()
#19 /var/www/html/index.php(47): MediaWiki->run()
#20 {main}</pre></body></html>liw@playground:~/mediawiki$
liw@playground:~/mediawiki$ ls -l cache
total 8
drwxr-xr-x 4 root root 4096 May 12 20:24 composer
drwx------ 3 root root 4096 May 12 20:27 sqlite
liw@playground:~/mediawiki$
```
I note that I was using docker and docker-compose as packaged by Debian and they might be versions that are too old. I so, please tell me.
```
liw@playground:~/mediawiki$ dpkg -l 'docker*'
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-=================-=========================-============-====================================
un docker <none> <none> (no description available)
ii docker-compose 1.21.0-3 all Punctual, lightweight development en
un docker-containerd <none> <none> (no description available)
un docker-doc <none> <none> (no description available)
un docker-runc <none> <none> (no description available)
ii docker.io 18.09.1+dfsg1-7.1+deb10u1 amd64 Linux container runtime
liw@playground:~/mediawiki$
```