Pick only one database.

See: https://community.fly.io/t/precise-steps-for-deploying-rails-8/23981

Author: rubys

lib/dockerfile-rails/scanner.rb

@@ -43,23 +43,30 @@ def scan_rails_app
 
       ### database ###
 
+      # start by checkout config/database.yml.  It defaults to sqlite3,
+      # but we can't rely on that because DATABASE_URL can override it.
+      # if we see anything else, assume the change was intentional.
       database = YAML.load_file("config/database.yml", aliases: true).
         dig("production", "adapter") rescue nil
 
-      if database == "sqlite3"
-        @sqlite3 = true
-      elsif database == "postgresql"
+      if database == "postgresql"
         @postgresql = true
       elsif (database == "mysql") || (database == "mysql2") || (database == "trilogy")
         @mysql = true
       elsif database == "sqlserver"
         @sqlserver = true
-      end
 
-      @sqlite3 = true if @gemfile.include? "sqlite3"
-      @postgresql = true if @gemfile.include? "pg"
-      @mysql = true if @gemfile.include?("mysql2") || using_trilogy?
-      @sqlserver = true if @gemfile.include?("activerecord-sqlserver-adapter")
+      ## if not found (or sqlite3), check the Gemfile
+      elsif @gemfile.include? "pg"
+        @postgresql = true
+      elsif @gemfile.include?("mysql2") || using_trilogy?
+        @mysql = true
+      elsif @gemfile.include?("activerecord-sqlserver-adapter")
+        @sqlserver = true
+      elsif @gemfile.include? "sqlite3" || database == "sqlite3"
+        # check this one last as sqlite3 may be used in development
+        @sqlite3 = true
+      end
 
       ### node modules ###
 

test/results/trilogy/Dockerfile

@@ -20,7 +20,7 @@ RUN gem update --system --no-document && \
 
 # Install base packages
 RUN apt-get update -qq && \
-    apt-get install --no-install-recommends -y curl default-mysql-client libjemalloc2 sqlite3 && \
+    apt-get install --no-install-recommends -y curl default-mysql-client libjemalloc2 && \
     rm -rf /var/lib/apt/lists /var/cache/apt/archives
 
 # Set production environment
@@ -35,7 +35,7 @@ FROM base AS build
 
 # Install packages needed to build gems
 RUN apt-get update -qq && \
-    apt-get install --no-install-recommends -y build-essential libyaml-dev pkg-config && \
+    apt-get install --no-install-recommends -y build-essential libyaml-dev && \
     rm -rf /var/lib/apt/lists /var/cache/apt/archives
 
 # Install application gems