Some quick notes on the file/repository architecture.
-Functionality is, as always, driven by data model.
+Functionality is, as always, driven by data model.
-* The repository object stores configuration information about a file storage
+* The repository object stores configuration information about a file storage
method.
* The file object is a process-local cache of information about a particular
FileRepo, where no such configuration is needed.
File objects are generated by a factory function from the repository. The
-repository thus has full control over the behaviour of its subsidiary file
+repository thus has full control over the behavior of its subsidiary file
class, since it can subclass the file class and override functionality at its
whim. Thus there is no need for the File subclass to query its parent repository
-for information about repository-class-dependent behaviour -- the file subclass
+for information about repository-class-dependent behavior -- the file subclass
is generally fully aware of the static preferences of its repository. Limited
exceptions can be made to this rule to permit sharing of functions, or perhaps
even entire classes, between repositories.
These rules alone still do lead to some ambiguity -- it may not be clear whether
to implement some functionality in a repository function with a filename
-parameter, or in the file object itself.
+parameter, or in the file object itself.
-So we introduce the following rule: the file subclass is smarter than the
+So we introduce the following rule: the file subclass is smarter than the
repository subclass. The repository should in general provide a minimal API
-needed to access the storage backend efficiently.
+needed to access the storage backend efficiently.
-In particular, note that I have not implemented any database access in
-LocalRepo.php. LocalRepo provides only file access, and LocalFile provides
+In particular, note that I have not implemented any database access in
+LocalRepo.php. LocalRepo provides only file access, and LocalFile provides
database access and higher-level functions such as cache management.
Tim Starling, June 2007
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff