Monday, 15 December 2014

ora:getAttachmentProperty: Failed to decode properties string

Last week I created a process that polls the usermessagingservice-email adapter to read emails and store the email with attachments as Oracle ACM case documents.

For simple e-mails this works fine, but with some emails I get the error:
0An error occurs while processing the XPath expression; the expression is ora:getAttachmentProperty('Content-Type', 'ReceiveMessage_ReceiveNotification_InputVariable','body', '/ns2:message/ns2:attachment[$AttachmentId]').XPath expression failed to execute.

An error occurs while processing the XPath expression; the expression is ora:getAttachmentProperty('Content-Type', 'ReceiveMessage_ReceiveNotification_InputVariable','body', '/ns2:message/ns2:attachment[$AttachmentId]').

The XPath expression failed to execute; the reason was: java.lang.RuntimeException: Failed to decode properties string ,att.contentId=1,Content-Type=multipart/related;

    boundary "---- _Part_188_790028878.1418047669530",.

Check the detailed root cause described in the exception message text and verify that the XPath query is correct.

XPath expression failed to execute

This occurs with both the functions ora:getAttachmentProperty and ora:getAttachmentContent.

It turns out that attachements that fail, are embedded attachments, like company logo's in autographs. They have a content-type like: "multipart/related", see the propertie string like:
 boundary "---- _Part_21_137200243.1418648527909",/related;
But 'real' attachments did work, and had a properties string like:
Content-Transfer-Encoding=base64,Content-Disposition=attachment,att.contentId=2,Content-ID=<>,Content-Type=image/jpeg; name DataSources.jpg,

Apparently, if the content-type in the properties string does not start with 'multipart', then the attachment is processable.
When you open the BPEL ReceiveMessage_ReceiveNotification_InputVariable input variable I got something like:
  <part xmlns:xsi="" name="body">
      <message xmlns="">
         <attachment href="409425ae-8448-11e4-a413-000c297d0a6d"/>
         <attachment href="409907af-8448-11e4-a413-000c297d0a6d"/>
         <attachment href="4099a3f0-8448-11e4-a413-000c297d0a6d"/>
         <attachment href="409a4031-8448-11e4-a413-000c297d0a6d"/>
         <opaqueElement xmlns="">PGh0bWwgeG1sbnM6dj0idXJuOnNjaGVtYXMtbWljcm9zb2Z0LWNvbTp2bWwiIHhtbG5zOm89InVy

In the Soa Infra database a table exists named 'ATTACHMENTS', with three columns: 'KEY', 'ATTACHMENT' and 'PROPERTIES'.

When you do a select on that table where the key the @href attribute, then you'll find the attachment. The PROPERTIES column contains the properties string like mentioned above.

So I created a DB Adapter config, with JNDI name 'eis/DB/SOA' (referring to already configured datasource in the DB Adapter), on this table. In the for-each loop I first query the attachment using the href attribute.

Then I extract the content-type using the expression
substring-before(substring-after($InvokeQuerySoaInfraAttachments_QuerySoaInfraAttachmentsSelect_OutputVariable.AttachmentCollection/ns6:Attachment/ns6:properties, 'Content-Type='),';')

In an IF statement using an expression like
not(starts-with($contentType, 'multipart'))
I only process those attachments that has content-type that is not multipart.

Probably a more sophisticated expression can be found.I could check on a list of only supporting mime-types.

To me this seems like a bug: SOASuite should be able to get the available properties out of the string to be able to process this.The main problem is also that the BPEL fault-handler is ignored: when the error occurs, the process fails! So I can't catch the exception and act on it. And honestly: I should not query the table myself, using the DB adapter, do I?

By the way: working with 12c (12.1.3), but I assume the same will occur in 11g.

1 comment :

Anonymous said...

For BPM. XPath Expression Builder. This should work in some flavor of BPEL too.

oraext:query-database(concat("select ATTACHMENT from ATTACHMENT where properties not like '%Content-type=multipart%' and key = '",
bpmn:getDataObject('email1_pdo')/ns:attachment[number(bpmn:getActivityInstanceAttribute('ACT16864252587573', 'loopCounter'))]/@href,"'")