Add experimental support for SQLite

Gemfile

@@ -7,6 +7,7 @@ end
 
 gem 'puma', '~> 5.6.2'
 gem 'mysql2', '~> 0.5.3'
+gem 'sqlite3'
 
 gem 'nokogiri', '< 1.13' # Locked because of Ruby >= 2.6 dependency
 gem 'thor', '<= 1.2.2' # Locked because of Ruby >= 2.6 dependency

Gemfile.lock

@@ -283,6 +283,7 @@ GEM
     spring-watcher-listen (2.0.1)
       listen (>= 2.7, < 4.0)
       spring (>= 1.2, < 3.0)
+    sqlite3 (1.4.4)
     strong_migrations (0.7.9)
       activerecord (>= 5)
     sync (0.5.0)
@@ -360,6 +361,7 @@ DEPENDENCIES
   spring
   spring-commands-rspec
   spring-watcher-listen (~> 2.0.0)
+  sqlite3
   strong_migrations
   terminal-table (~> 3.0)
   thor (<= 1.2.2)

README.md

@@ -23,19 +23,27 @@ Please view our [guide](docs/installation.md) to assist you in the RMT installat
     sudo zypper in libxml2-devel libxslt-devel libmariadb-devel gcc
     ```
 2. Install the ruby version specified in the `.ruby-version` [file](.ruby-version).
-3. Install and start either the MariaDB or MySQL server:
+3. Install and setup the database:
+
+   **Default: MariaDB or MySQL server**
     ```
     sudo zypper in mariadb
     sudo systemctl enable mariadb
     sudo systemctl start mariadb
     ```
-4. Log into the MariaDB or MySQL server as root and create the RMT database user:
+    Log into the MariaDB or MySQL server as root and create the RMT database user:
     ```
     mysql -u root -p <<EOFF
     GRANT ALL PRIVILEGES ON \`rmt%\`.* TO rmt@localhost IDENTIFIED BY 'rmt';
     FLUSH PRIVILEGES;
     EOFF
     ```
+
+    **Experimental: SQLite**
+
+    For development purposes it can be easier to run with SQLite, to avoid extra dependencies.
+    To run RMT with SQLite, switch the database adapter in `config/rmt.yml` to `sqlite3`.
+
 5. Clone the RMT repository:
     ```
     git clone git@github.com:SUSE/rmt.git

bin/rmt-cli

@@ -45,6 +45,11 @@ end
 db_config = RMT::Config.db_config
 ActiveRecord::Base.establish_connection(db_config)
 
+if ActiveRecord::Base.connection.adapter_name != "Mysql2"
+  warn "Running with experimental support for #{ActiveRecord::Base.connection.adapter_name}."
+  warn 'RMT is running without locking operations, make sure not to run it in multipe processes.'
+end
+
 begin
   RMT::CLI::Main.start(ARGV)
 rescue Interrupt

lib/rmt/cli/base.rb

@@ -1,6 +1,7 @@
 require 'rmt/lockfile'
 require 'rmt/cli/decorators'
 require 'etc'
+require 'mysql2'
 
 class RMT::CLI::Base < Thor
 

lib/rmt/lockfile.rb

@@ -3,6 +3,8 @@ class RMT::Lockfile
 
   class << self
     def lock(lock_name = nil)
+      yield and return if ActiveRecord::Base.connection.adapter_name != 'Mysql2'
+
       lock_name = ['rmt-cli', lock_name].compact.join('-')
 
       is_lock_obtained = obtain_lock(lock_name)