derive from php:7.2-alpine;

artisan koel:init still reports 'could not find driver'

/koel # php artisan koel:init
...

Koel cannot connect to the database. Let's set it up.

 Your DB driver of choice [MySQL/MariaDB]:
  [mysql     ] MySQL/MariaDB
  [pgsql     ] PostgreSQL
  [sqlsrv    ] SQL Server
  [sqlite-e2e] SQLite
 > pgsql

 DB host:
 > koel-db

...

could not find driver

Koel cannot connect to the database. Let's set it up.

...

/koel # php -m | grep pg
pgsql

/koel # php -r "print_r(get_loaded_extensions());" | grep pg
    [33] => pgsql

Dockerfile

@@ -1,22 +1,17 @@
-# consider switching to https://hub.docker.com/_/php/
-FROM alpine:3.8
+FROM php:7.2-alpine
+
+# postgresql-dev: required for build of pgsql (includes libpq-fe.h)
+RUN apk add postgresql-dev
+# zlib-dev: required by zip module
+RUN apk add zlib-dev
+RUN docker-php-ext-install -j$(nproc) \
+    exif \
+    pgsql \
+    zip
 
 RUN apk add \
-	composer \
-	git \
-	php7-curl \
-	php7-dom \
-	php7-exif \
-	php7-fileinfo \
-	php7-iconv \
-	php7-pdo \
-	php7-simplexml \
-	php7-tokenizer \
-	php7-xml \
-	php7-xmlwriter \
-	php7-zip \
-    php7-pgsql \
-    php7-session
+    composer \
+    git
 
 RUN git clone --branch master https://github.com/phanan/koel /koel
 WORKDIR /koel
@@ -25,3 +20,5 @@ WORKDIR /koel
 # The only supported ciphers are AES-128-CBC and AES-256-CBC with the correct key lengths.
 RUN sed 's/^APP_KEY=$/APP_KEY=WORKAROUND_000000000000000000000/' .env.example >.env
 RUN composer install --no-interaction
+
+CMD ["sh"]