imscpv1p2.rst

IMS Content Packaging (version 1.2)

The IMS Content Packaging specification defines methods for packaging and organizing resources and their associated metadata for transmission between systems. There is a small amount of information on Wikipedia about content packaging in general, see http://en.wikipedia.org/wiki/Content_package. The main use of IMS Content Packaging in the market place is through the SCORM profile. Content Packaging is also used as the basis for the new IMS Common Cartridge, and a method of packaging assessment materials using the speicifcation is also described by IMS QTI version 2.1.

Official information about the specification is available from the IMS GLC: http://www.imsglobal.org/content/packaging/index.html

Example

The following example script illustrates the use of this module. The script takes two arguments, a resource file to be packaged (such as an index.html file) and the path to save the zipped package to. The script creates a new package containing a single resource with the entry point set to point to the resource file. It also adds any other files in the same directory as the resource file, using the python os.walk function to include files in sub-directories too. The :pyContentPackage.IgnoreFilePath method is used to ensure that hidden files are not added:

#! /usr/bin/env python

import sys, os, os.path, shutil
from pyslet.imscpv1p2 import ContentPackage, PathInPath
from pyslet.rfc2396 import URIFactory

def main():
    if len(sys.argv)!=3:
        print "Usage: makecp <resource file> <package file>"
        return
    resFile=sys.argv[1]
    pkgFile=sys.argv[2]
    pkg=ContentPackage()
    try:
        if os.path.isdir(resFile):
            print "Resource entry point must be a file, not a directory."
            return
        resHREF=URI.from_path(resFile)
        srcDir,srcFile=os.path.split(resFile)
        r=pkg.manifest.root.Resources.ChildElement(pkg.manifest.root.Resources.ResourceClass)
        r.href=str(resHREF.relative(URI.from_path(os.path.join(srcDir,'imsmanifest.xml'))))
        r.type=='webcontent'
        for dirpath,dirnames,filenames in os.walk(srcDir):
            for f in filenames:
                srcPath=os.path.join(dirpath,f)
                if pkg.IgnoreFilePath(srcPath):
                    print "Skipping: %s"%srcPath
                    continue
                dstPath=os.path.join(pkg.dPath,PathInPath(srcPath,srcDir))
                # copy the file
                dName,fName=os.path.split(dstPath)
                if not os.path.isdir(dName):
                    os.makedirs(dName)
                print "Copying: %s"%srcPath
                shutil.copy(srcPath,dstPath)
                pkg.File(r,URI.from_path(dstPath))
        if os.path.exists(pkgFile):
            if raw_input("Are you sure you want to overwrite %s? (y/n) "%pkgFile).lower()!='y':
                return
        pkg.manifest.Update()
        pkg.ExportToPIF(pkgFile)
    finally:
        pkg.Close()

if __name__ == "__main__":
    main()

Note the use of the try:... finally: construct to ensure that the :pyContentPackage object is properly closed when it is finished with. Note also the correct way to create elements within the manifest, using the dependency safe *Class attributes:

r=pkg.manifest.root.Resources.ChildElement(pkg.manifest.root.Resources.ResourceClass)

This line creates a new resource element as a child of the (required) Resources element.

At the end of the script the :pyManifestDocument is updated on the disk using the inherited :py~pyslet.xml20081126.structures.Document.Update method. The package can then be exported to the zip file format.

Reference

ContentPackage

ManifestDocument

Constants

The following constants are used for setting and interpreting XML documents that conform to the Content Packaging specification

IMSCP_NAMESPACE

IMSCP_SCHEMALOCATION

IMSCPX_NAMESPACE

Elements

CPElement

Manifest

Metadata

Schema

SchemaVersion

Organizations

Organization

Resources

Resource

File

Dependency

Utilities

PathInPath