Back Forward Understanding work item attachments

Concepts and terms

A work item attachment identifies a named file, screen shot image, URL or text note that a user or an activity has associated with a work item. On the standard portals and user form, a paper clip button or Attachmentsprovides access to review or add attachments.

Classes for attachments

The system stores attachments in instances of these concrete classes, subclasses of the Data-Work Attach- class:

By default, work item attachments are stored as rows of the pc_data_workattach table. Note that attachments are not stored in the same database table as the work items themselves. (Note that this table is not used for file attachments when the CMIS option is selected. See below.)

File attachments

When a user designates a file as an attachment, the system uploads a copy of the file and links it to the history of the work item. The system saves attachments for correspondence in HTML format (HTM file type) even if a user edited the correspondence with Microsoft Word. If the correspondence includes embedded images or other embedded objects, the attachment is saved as a ZIP archive (ZIP file type) containing the objects and the HTM file. The system converts the ZIP file internally into characters using Base64 encoding.

The description text (Subject field) of a file attachment is limited to 60 characters.

By default, file attachments are restricted to 1 gigabyte in size. You can set a larger or smaller limit with the prconfig.xml file setting:

<env name="Initialization/MaximumFileUploadSizeMB" value="nn" />

where nn is the size in megabytes. (In V5.5 and earlier releases, the default limit was 25MB.)

As an alternative to the prconfig.xml file, you can use Dynamic System Settings to configure your application.
See How to create or update a prconfig setting.

If a user accesses the PRPC server with the HTTPS protocol (rather than HTTP), this may block certain download operations from the server to the workstation. For details and suggestions, see PDN article PDN 17997 Troubleshooting: "Internet Explorer cannot download " messages (Tomcat with SSL).

Optionally, you can choose to store file attachments for an application in an external content management system such as Alfresco. This capability requires the optional Pega-Connect RuleSet.

Storing file attachments in an external enterprise content management system

You can configure your application to store attachments of type file in an external enterprise content management system using the CMIS protocol. This option is enabled by a checkbox on the application rule. See About Connect CMIS rules and PDN article PDN 26269 How to integrate your application with a content management system . Informally, these are known as content attachments.

URL and URI attachments

URL and URI attachments can provide flexibility and power while requiring little storage. A URL can point to a document or file on an intranet or the World Wide Web. A URL can also cause PRPC to execute an activity in your application; the activity can search or retrieve a document or file, call an external system, and so on. See PDN article PDN 16586 Linking to external documents versus importing them as work item attachments.

Screen shot (screen capture) attachments

A user can capture a screen image of any open window as a JPG file, known as a screen shot attachment. The JPG file is stored internally as characters using Base64 encoding. Use the Advanced View of the standard History and Attachments display to enter screen shot attachments

Scanned document attachments

A user with a scanner attached to her workstation can use Pega Document Scanning to scan documents and attach them as TIFF or GIF image files to work items. The standard Work-.pyCreateScannedDocument local flow action starts this operation. The user can also configure scanner defaults from this flow action.

Use the Work-.ViewImageAttachments flow action to view scanned image attachments from within the PRPC application. Use the Advanced View of the standard History and Attachments display to enter screen shot attachments.

Virus checking

Files received from any source might contain computer viruses. You can connect your application's processing of work item attachments to an external virus-checking module. Virus checking occurs before the system saves the attachment to the database. Override the standard extension point activity Data-WorkAttach-File.CallVirusCheck to call the checker and modify processing by the flow to handle files reported to contain viruses. The virus check module can be a Java routine or (when PRPC is hosted on Microsoft Windows) in a Windows DLL file.

Limits

While the number of attachments you can add to a work item is unlimited, the standard list view rule  Link-Attachment.AttachmentList.ALL displays only up to 100 attachments. You can override this rule if necessary.

Attachments and search results

If the Index Attachments checkbox is checked in the Search tab of the System landing page (Pega> System > Settings > Search), a search of work items in a composite User portal can include searching the contents of text-file attachments for a specified word or text string. See Understanding full-text search.

Conversion of DOC to PDF format

PRPC provides two approaches to convert Word DOC files to Portable Document (PDF) formats. For each approach, the original DOC file and the converted PDF file become two file attachments, typically of separate categories:

To convert in the background:

  1. Install PegaDISTRIBUTION Manager 3.3.5 on an appropriate Windows server.
  2. Add the Utility activity Work-.ConvertAttachmentToPDF to the flow, supplying as parameters both the name of the existing DOC attachment category and the target attachment category for the PDF file.
  3. In later flow processing, ensure that outgoing correspondence that needs to include the PDF file is not sent until PegaDISTRIBUTION Manager returns the PDF attachment. Conversion can take several minutes.

To convert in the foreground, include the standard flow action .Work-.ConvertAttachmenttoPDF as a local flow action in appropriate assignments in the flow. Users must select this flow action, complete the form, and wait for workstation conversion.

Attachment category rules

You can support attachments with attachment category rules to control the user's ability to add, view, edit, or delete attachments. For more information, see Attachment category.

Definitions assignment, attachment category, attachment type, base64 encoding, correspondence, note attachment, PegaDISTRIBUTION Manager, perform, screen shot attachment, work item
Related topics How to define and use attachment categories and versions
About Attachment Category rules
About audit trails and attachments (V6X)
User portal basics — About work item history and attachments (V5)
How to call a Windows DLL library
About the Scan Station
Using the Image Viewer

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