Use built-in ActiveRecord URL resolver (#294)

CHANGELOG.md

@@ -2,6 +2,7 @@
 All notable changes to this project will be documented in this file.
 
 ## Unreleased
+- Use ActiveRecord URL resolver instead of copying definition [#294](https://github.com/instacart/makara/pull/294) Matt Larraz
 - Deprecated the term `master` in favor of `primary` [#290](https://github.com/instacart/makara/pull/290) Matt Larraz
 - Deprecated the term `slave` in favor of `replica` [#286](https://github.com/instacart/makara/pull/286) Matt Larraz
 - Drop support for Ruby < 2.5 and ActiveRecord < 5.2 [#281](https://github.com/instacart/makara/pull/281) Matt Larraz

lib/makara/config_parser.rb

@@ -37,99 +37,13 @@ class ConfigParser
       master_ttl:           :primary_ttl
     }.freeze
 
-    # ConnectionUrlResolver is borrowed from Rails 4-2 since its location and implementation
-    # vary slightly among Rails versions, but the behavior is the same.  Thus, borrowing the
-    # class should be the most future-safe way to parse a database url.
-    #
-    # Expands a connection string into a hash.
-    class ConnectionUrlResolver # :nodoc:
-      # == Example
-      #
-      #   url = "postgresql://foo:bar@localhost:9000/foo_test?pool=5&timeout=3000"
-      #   ConnectionUrlResolver.new(url).to_hash
-      #   # => {
-      #     "adapter"  => "postgresql",
-      #     "host"     => "localhost",
-      #     "port"     => 9000,
-      #     "database" => "foo_test",
-      #     "username" => "foo",
-      #     "password" => "bar",
-      #     "pool"     => "5",
-      #     "timeout"  => "3000"
-      #   }
-      def initialize(url)
-        raise "Database URL cannot be empty" if url.blank?
-
-        @uri     = URI.parse(url)
-        @adapter = @uri.scheme.tr('-', '_')
-        @adapter = "postgresql" if @adapter == "postgres"
-
-        if @uri.opaque
-          @uri.opaque, @query = @uri.opaque.split('?', 2)
-        else
-          @query = @uri.query
-        end
-      end
-
-      # Converts the given URL to a full connection hash.
-      def to_hash
-        config = raw_config.reject { |_,value| value.blank? }
-        config.map { |key,value| config[key] = CGI.unescape(value) if value.is_a? String }
-        config
-      end
-
-      private
-
-      def uri
-        @uri
-      end
-
-      # Converts the query parameters of the URI into a hash.
-      #
-      #   "localhost?pool=5&reaping_frequency=2"
-      #   # => { "pool" => "5", "reaping_frequency" => "2" }
-      #
-      # returns empty hash if no query present.
-      #
-      #   "localhost"
-      #   # => {}
-      def query_hash
-        Hash[(@query || '').split("&").map { |pair| pair.split("=") }]
+    ConnectionUrlResolver =
+      if ::ActiveRecord::VERSION::STRING >= "6.1.0"
+        ::ActiveRecord::DatabaseConfigurations::ConnectionUrlResolver
+      else
+        ::ActiveRecord::ConnectionAdapters::ConnectionSpecification::ConnectionUrlResolver
       end
 
-      def raw_config
-        if uri.opaque
-          query_hash.merge({
-            "adapter"  => @adapter,
-            "database" => uri.opaque })
-        else
-          query_hash.merge({
-            "adapter"  => @adapter,
-            "username" => uri.user,
-            "password" => uri.password,
-            "port"     => uri.port,
-            "database" => database_from_path,
-            "host"     => uri.host })
-        end
-      end
-
-      # Returns name of the database.
-      def database_from_path
-        if @adapter == 'sqlite3'
-          # 'sqlite3:/foo' is absolute, because that makes sense. The
-          # corresponding relative version, 'sqlite3:foo', is handled
-          # elsewhere, as an "opaque".
-
-          uri.path
-        else
-          # Only SQLite uses a filename as the "database" name; for
-          # anything else, a leading slash would be silly.
-
-          uri.path.sub(%r{^/}, "")
-        end
-      end
-    end
-
     # NOTE: url format must be, e.g.
     # url: mysql2://...
     # NOT