[python-ldap] Modlist with a replace sometimes fails

[William]

Hi,

I never heard back about whether the below patch is acceptable. I do not change
the default behaviour, only add the ability to use MOD_REPLACE if the user wishes
it.

Thanks,

On Fri, 2016-02-19 at 09:23 +1000, William wrote:
> diff --git a/Lib/ldap/modlist.py b/Lib/ldap/modlist.py
> index 0053a3f..a56c3e5 100644
> --- a/Lib/ldap/modlist.py
> +++ b/Lib/ldap/modlist.py
> @@ -49,7 +49,7 @@ def addModlist(entry,ignore_attr_types=None):
>  
>  
>  def modifyModlist(
> -  old_entry,new_entry,ignore_attr_types=None,ignore_oldexistent=0,case_ignore_
> at
> tr_types=None
> +  old_entry,new_entry,ignore_attr_types=None,ignore_oldexistent=0,case_ignore_
> at
> tr_types=None,replace_is_add_then_delete=True
>  ):
>    """
>    Build differential modify list for calling LDAPObject.modify()/modify_s()
> @@ -69,6 +69,10 @@ def modifyModlist(
>    case_ignore_attr_types
>        List of attribute type names for which comparison will be made
>        case-insensitive
> +  replace_is_add_then_delete
> +      Determines if a replace operation is carried out as add then delete
> +      or if it is a pure ldap replace. This can have behavioural affects on
> +      certain ldap servers and object types IE configuration directories.
>    """
>    ignore_attr_types = list_dict(map(lower,(ignore_attr_types or [])))
>    case_ignore_attr_types = list_dict(map(lower,(case_ignore_attr_types or
> [])))
> @@ -111,8 +115,11 @@ def modifyModlist(
>                replace_attr_value = 1
>                break
>        if replace_attr_value:
> -        modlist.append((ldap.MOD_DELETE,attrtype,None))
> -        modlist.append((ldap.MOD_ADD,attrtype,new_value))
> +        if replace_is_add_then_delete:
> +          modlist.append((ldap.MOD_DELETE,attrtype,None))
> +          modlist.append((ldap.MOD_ADD,attrtype,new_value))
> +        else:
> +          modlist.append((ldap.MOD_REPLACE,attrtype,new_value))
>      elif old_value and not new_value:
>        # Completely delete an existing attribute
>        modlist.append((ldap.MOD_DELETE,attrtype,None))
> 

-- 
William <william at blackhats.net.au>