issue is local to 1.2 so isn't present in production systems On Mon, Dec 4, 2017 at 4:26 PM, Mike Bayer <mike...@zzzcomputing.com> wrote: > On Mon, Dec 4, 2017 at 2:18 PM, Olaf <bastien...@gmail.com> wrote: >> Hello, >> >> >> >> This mail is the continuation of this question: >> https://groups.google.com/forum/#!topic/sqlalchemy/Ba7urbeZBqQ >> >> >> >> The problem being different, I prefer to open a new topic. >> >> >> >> I am currently meeting a problem regarding generic associations and the use >> of MutableList associated to the array type of postgres. >> >> >> >> I coded two versions of the same case: >> >> - the first one uses a generic association. The attribute "text" should be a >> MutableList but suddenly becomes a "List" during the first commit. The next >> changes are therefore not longer detected and the data are not actualized in >> the database >> >> - the second example is a classical relationship. In this case, the >> attribute "text" is a MutableList and don't changes during the commits. >> Everything works as it should and the data are actualized in the database > > this is > https://bitbucket.org/zzzeek/sqlalchemy/issues/4141/array-does-not-fire-attachment-events. > Please use @declared_attr for now. > > class Mixin(object): > @declared_attr > def data(cls): > return Column(MutableList.as_mutable(postgresql.ARRAY(String))) > > > > >> >> >> >> It will be easier to see the problem with the two examples and their output. >> >> >> The examples are attached. >> >> >> >> Example 1 - Generic Association Code (don't works as it should): >> >> >> >> Output: >> >> >> >>>>> >> Text before commit 1: ['Rex is a', 'good dog...'] >> Type before commit 1: <class 'sqlalchemy.ext.mutable.MutableList'> >> Commit 1 >> Type after commit 1: <class 'list'> >> We append duck sentence : ['Rex is a', 'good dog...', 'but I prefer >> ducks.'] >> Commit 2 >> Text after commit 2 : ['Rex is a', 'good dog...'] >>>>> >> >> >> >> >> Example 2 - Classical relationship (works fine): >> >> >> >> Output: >> >> >> >>>>> >> Text before commit 1: ['Rex is a', 'good dog...'] >> Type before commit 1: <class 'sqlalchemy.ext.mutable.MutableList'> >> Commit 1 >> Type after commit 1: <class 'sqlalchemy.ext.mutable.MutableList'> >> We append duck sentence : ['Rex is a', 'good dog...', 'but I prefer >> ducks.'] >> Commit 2 >> Text after commit 2 : ['Rex is a', 'good dog...', 'but I prefer ducks.'] >>>>> >> >> >> >> >> I don't know if it helps but I noticed that the __init__ method of the class >> Description doesn't have exactly the same behavior in the two examples: >> >> >> >> - in the Generic Association Code example, the "self.text = MutableList()" >> in the __init__ method of the class Description is not really important. It >> could also be "self.text = []" instead. In all cases, text is a MutableList. >> >> - in the Classical relationship example, if the __init__ method of the class >> Description contains "self.text = MutableList()", the attribute text will be >> a MutableList and if the __init__ method contains "self.text = []", it will >> be a List. >> >> >> >> Does someone have an explanation ? >> >> >> >> Thank you ! >> >> -- >> SQLAlchemy - >> The Python SQL Toolkit and Object Relational Mapper >> >> http://www.sqlalchemy.org/ >> >> To post example code, please provide an MCVE: Minimal, Complete, and >> Verifiable Example. See http://stackoverflow.com/help/mcve for a full >> description. >> --- >> You received this message because you are subscribed to the Google Groups >> "sqlalchemy" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to sqlalchemy+unsubscr...@googlegroups.com. >> To post to this group, send email to sqlalchemy@googlegroups.com. >> Visit this group at https://groups.google.com/group/sqlalchemy. >> For more options, visit https://groups.google.com/d/optout.
-- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
