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By Bryan Quinn
+ +Tcl API
Tcl API
apm-install-procs.tcl (Supports installation of packages)
20-apm-load-procs.tcl (Bootstraps APM for server startup)
OpenACS Applications: a "program or group of programs -designed for end users" (the Webopedia +
OpenACS Applications: a "program or group of programs +designed for end users" (the Webopedia definition); also known as modules, for historical reasons. Examples of applications include Forums and News. @@ -87,15 +88,15 @@ packages for other OpenACS users to download and install.
For a simple illustration of the difference between ACS without APM (pre-3.3) and ACS with APM (3.3 and beyond), consider a hypothetical ACS installation that uses only two of the thirty-odd modules available circa ACS -3.2 (say, bboard and e-commerce):
APM itself is part of a package, the OpenACS Kernel, an OpenACS +3.2 (say, bboard and e-commerce):
APM itself is part of a package, the OpenACS Kernel, an OpenACS service that is the only mandatory component of an OpenACS installation.
The OpenACS is a platform for web-based application software, and any software platform has the potential to develop problems like those described above. Fortunately, there are many precedents for systematic solutions, including:
Borrowing from all of the above, OpenACS 3.3 introduces its own package management system, the OpenACS Package Manager (APM), which consists of:
a standard format for APM packages (also called -"OpenACS packages"), including:
version numbering, independent of any other package and the OpenACS as a +"OpenACS packages"), including:
version numbering, independent of any other package and the OpenACS as a whole
specification of the package interface
specification of dependencies on other packages (if any)
attribution (who wrote it) and ownership (who maintains it)
web-based tools for package management:
obtaining packages from a remote distribution point
installing packages, if and only if:
all prerequisite packages are installed
no conflicts will be created by the installation
configuring packages (obsoleting the monolithic OpenACS configuration file)
upgrading packages, without clobbering local modifications
uninstalling unwanted packages
a registry of installed packages, database-backed and integrated with filesystem-based version control