How does ProjectWise Integration Server V8 XM use MIME types?

The purpose of this document is to present how ProjectWise Integration Server V8 XM uses the document MIME type. This information is important to understand when upgrading ProjectWise datasources from pre-XM versions to the XM version. Since setting the document MIME type during a database conversion is an optional task, the information presented in this document should provide the reader with the information needed to make the decision of when and why the MIME type conversion should be performed.

MIME (Multipurpose Internet Mail Extensions) is a specification for formatting non-ASCII messages so they can be sent over the Internet. ProjectWise uses file MIME types for integration with AutoCAD and MicroStation, and also for attribute exchange. Some well-known file types may not get a MIME type assigned in ProjectWise, due to the fact that ProjectWise currently does not need a MIME type value in order to correctly process those file types. This is the intended behavior.

The purpose of this document is to provide an explanation of why MIME types are important to ProjectWise, how ProjectWise uses MIME types, and what considerations should be given to MIME type management.

MicroStation Integration

MIME type management was introduced in ProjectWise V8 XM Edition (8.9.2.33) to support the distributed DGN functionality. Because only V8 DGN files can be made shareable, ProjectWise uses the MIME type of each DGN file to determine whether it is a V8 DGN or a V7 DGN. For this reason, V7 DGN files and V8 DGN files have been assigned different MIME types:

• V7 = image/vnd.dgn
• V8 = image/vnd.dgn;ver=8

So now when files are imported into ProjectWise, ProjectWise stores the MIME type of each file in the database, and use that database value to determine whether the DGN file can be made shareable or not.

AutoCAD Integration

For AutoCAD, ProjectWise uses the file MIME type for the reference file management. Since the 8.9.3 version of ProjectWise V8 XM, changes to reference file sets made during the session are not written to the database until the server copy of the file is updated, either using the update server copy command or when the file is checked in (unless the computer has the HKEY_CLASSES_ROOT\AutoCAD\ODMA32\ODMSave) registry key set to update the server on each AutoCAD save command.) This prevents the database from getting out-of-synch with the drawing when the user frees the file after making changes to the reference file set. ProjectWise records changes to the reference file set made during the session locally on the client, and updates the database with the set changes on server update. For this process to work correctly, the MIME type of the DWG file must be set to image/vnd.dwg, or the database will not be updated with the new reference set information.

Attribute Exchange\Titleblocks

Starting with the 8.9.4 version of ProjectWise V8 XM, all types of attribute exchange require the proper MIME type to be set for the document. This includes:

• Manual update on user request (menu item or MicroStation key-in such as dmsupdate)
• Automatic update on document open
• Automatic update on document copy-out operation
• Automatic update on document check-out operation
• Automatic update on document export operation (starting with ProjectWise V8 Athens (8.11))
• Manual update on multiple documents using the Bulk Update tool

The attribute exchange configuration information is stored in the computer registry (for ProjectWise V8 XM Edition, the version string will be 08.09):

• HKEY_LOCAL_MACHINE\SOFTWARE\Bentley\ProjectWise iDesktop Integration\08.11\TitleBlocks\Tools\Auto Update
• HKEY_LOCAL_MACHINE\SOFTWARE\Bentley\ProjectWise iDesktop Integration\08.11\TitleBlocks\Tools\Bulk Extract

Under these keys there are sub-keys for each application:

• MS Excel, MS Word, Ustation, AutoCAD r15, AutoCAD r16, AutoCAD r17

Under each of these sub-keys there will be following registry values:

• Name: FileType
• Type: REG_MULTI_SZ
• Value: values are different, depends on application

This value is a list of all MIME types that are supported by a given updating system. Therefore, a document must have one of these MIME types set to have any attributes updated. Otherwise, no attribute update will occur for that specific document.

Raster Streaming

Dynamically downloading, or streaming, raster data with integrated MicroStation was introduced in the ProjectWise V8 XM 8.9.2.33 release.  This technology depends on the raster file that is being streamed having a ProjectWise MIME type set to “raster”. 

Creating MIME Types

When you create a document in ProjectWise, whether by using a document creation wizard, no wizard, or by dragging files from the file system, ProjectWise sets the MIME type, if known, for each file. MIME types are stored in the DMS_DOC table, in the O_MIMETYPE field. However, pre-V8 XM datasources have no concept of MIME types. When pre-V8 XM datasources are upgraded to V8 XM Edition, the MIME types will still not be determined. To set MIME types for these files, a MIME type bulk update must be performed. This can be accomplished using the DMSCONV tool. The DMSCONV tool will prompt the user to update the MIME types of these files as part of the database upgrade to a V8 XM platform. This does not have to be done as part of the conversion; it can be run after a datasource is converted. The DMSCONV tool will issue a MIME query command to the storage area for each file to determine the MIME type; note that this is a read-only operation, and the file is NOT transferred or modified during this process.

Also, the MIME type conversion process can also be stopped before completion, and when run at a later time, the process will start up where it left off and not reprocess files it has already processed. Because not all file types need to have a MIME type assigned, the MIME type determination process can be accelerated by defining an exclusion list on the DMSCONV command line. Files with matching extensions will be ignored for MIME type determination purposes. See the DMSCONV command-line help for examples.

While it is always recommend having your database completely up-to-date, including MIME types, you can assess how time-critical it is to have all MIME types converted. Upgrading the MIME types from a pre-V8 XM datasource is most important for reference file handling in AutoCAD, and for attribute exchanges\title block updates.

Summary of MIME Type Usage Introduction