Archiving and transferring objects

Creating an archive transforms copies of a set of objects (folders, documents, discussion forums etc.) into one compact document, thus saving storage space and download time. Ar­chives are espe­cially useful for downloading numerous or big files. You may also encode the resulting ar­chive document – usually with the aim of further reducing the size of an archive.

On the one hand, you may archive objects in BSCW in order to download the archive to your local computer, extract the original files there or to send the whole archive per email to some other person. On the other hand, you may pack local files and folders into an archive (Zip/ Winzip or Tar), up­load the archive to a BSCW workspace and extract the original files and folders. You may also archive whole BSCW workspaces in order to extract them on the same or some other BSCW server at a later point in time.

You may optionally also have BSCW metadata archived along with the objects. The optional archiving of metadata in form of an XML file supplies additional information on the objects archived and may be evaluated automatically by other programs. When extracting an archive with metadata on a BSCW server of version 5.0 or later, the objects are restored along with their metadata.

You should take into account that not all types of objects may be archived and that not all metadata – such as event history, attachments or ratings for example – may be archived. This means that archiving and extraction without any loss of information is not possible. Details on which object types and which metadata may be archived are to be found below in this section.

In order to archive a set of objects you proceed as follows.

•      Select (check-mark) the entries of the objects that you want to include in the archive file. Your clipboard may be helpful in bringing together objects from ‘distant’ loca­tions that you want to include in one archive file.

•      Click archive in the multi-selection toolbar to bring up the ‘Archive’ form. It in­cludes a list of the archive types that your BSCW server can produce, and of the en­coding methods that may be applied to the archive file. The archive types and encoding meth­ods offer­ed depend on the configuration of your BSCW server.

•      Enter the name of the archive.

•      Click one of the ‘Storage’ options to specify where the archive shall go: download only, add to clipboard or add to current folder.

•      Check the option ‘create index file’ if BSCW is to create an index file of the entries ar­chived. The file index.html is a table of contents of the archive also containing some meta­data like the descriptions of the objects archived.

•      Check the option ‘create metadata file’ if BSCW is to create an XML file .bscw con­taining some metadata of the objects archived. This minimizes loss of information when the archive is extracted again on the same or another BSCW server. Which meta­data may be archived at all is explained below.

•      Select the archive type which fits your local computer platform and eventually select the encoding to be applied.

•      Start archiving by clicking [OK].

With smaller archives, the message ‘Archive created’ appears with a link to the ar­chive and a list of the objects that could not be archived. The types of objects that can­not be archived are listed below. If the option ‘download only’ has been selected, the archive created is offered for immediate download.

With bigger archives, the archiving process is executed in background. In this case, the message ‘Archiving in progress’ appears and you will receive an email message to your primary address when archiving has been completed. This message contains a link to the archive and a list of those objects that could not be archived.

If you have chosen the option ‘download only’ with bigger archives, the archive is appended to the notification email message or – with very large archives – is stored in your clipboard; in the latter case the notification contains a link to the archive.

Note: In order to open archives downloaded to a local computer, the necessary extraction pro­grams have to be installed and the Web browser has to be configured to start these programs when archive files of the respective MIME types are encountered. When en­coding is used, match­ing decoding programs have to be installed and the Web browser has to be configured to start these programs when encoded archive files of the respec­tive MIME types are en­coun­ter­ed.

In order to upload local files to a workspace via the archive mechanism you proceed as fol­lows:

•      Create an archive of the files you want to upload on your local computer (Zip/Winzip or Tar archives depending on your platform; also an email message with documents attached will work as an RFC822 archive if available on your BSCW server).

•      Upload the archive document to one of your workspaces.

•      Extract the original files by invoking action  Extract  in the action menu of the archive do­cument. This will create the original files as documents in your clipboard.

With smaller archives, a message ‘Archive extracted’ appears along with a list of the objects extracted.

With bigger archives, you receive a message ‘Extraction in progress’ – extraction is executed in background. You will be informed by a further message when ex­traction has been completed.

•      Files extracted to your clipboard are ready to be pasted to some appropriate place in your folder hierarchy.

Archivable and non-archivable types of objects

The following types of object may be archived:

o  folders

o  documents

o  contact lists and contacts

o  calendars and appointments

o  blogs and discussion forums with notes

o  website folders

o  URL objects and RSS folders

Such objects are restituted from an archive in all essential aspects during extraction, if meta­data have been archived as well. With other object types, e.g. tasks or flow folders, many details are lost when extracted from an archive.

The following types of objects cannot be archived:

o  polls, votings and appointment schedulings

o  workspace portals and their widgets

Archivable and non-archivable metadata

The following metadata may optionally be archived:

o  name, description and further details of objects archived,

o  creator and date of creation,

o  BSCW specific data like object type and object number.

The following metadata are never archived and are not available after extraction of an archive in BSCW:

o  events and history (apart from creation and the extraction itself),

o  members and access rights, i.e. workspaces are archived as ordinary folders,

o  attachments and ratings,

o  auto-versioning options concerning documents and folders,

o  locks and versions of documents,

o  participants, reminders, tags and user-defined attributes of appointments,

o  start and end dates of projects, phases and tasks,

o  responsibles, states and details of tasks and flow folders.