Constructor accepts mixed values which leads to bug

[lordrhodos]

Problem

As discussed earlier today the following flow will create a bug

quote from @felixsand earlier in slack today

1. Initiate a new Db object using a PDO object: $db = new Db($existingPdo);
2. Now disconnect: $db->disconnect();
3. What happens now next time $db->connect() is called? No pdo OR dsn is available

Will probably lead to an unexpected Exception of some sort when a new PDO object is trying to get created when just null will be sent in as dsn, username and password, no?

Solution

I suggest the following to solve this issue in the long term:

• allow only PDO object to be passed into the container in a version 1.0.0
• deprecate usage of the two other approaches now
• add static replacement methods to support creating a Db instance by passing in a dns or host, username password and options
• refactor and the fix the connection issue described above

[lordrhodos]

after looking a little bit deeper into the code and how PDO is handling connections I have to adjust my suggested solution to the following

• drop support for passing PDO objects into the constructor
• drop support to pass in a host and a database and let the Db create the dsn
• support only a PDO dsn string, username (optional) and password (optional)
• introduce a PdoFactoryInterface (optional) as constructor argument and a default implementation creating the PDO instances