Rendering objectStream response from CMIS

Hello,

We want a user to be able to click a link in an web application, which will invoke a service that will return the document to the user (i.e. as a download). The response from getObjectStream includes a filename, file type, and base64binary stream.

Is there a standard or recommended way to handle the getObjectStream response, converting the base64binary into an actual file for the user to download? Is there any other way to make this link work in such a way that the user does not need to authenticate to Content Server, as the authentication will be built into the request?

Thank you.

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eLink User

Hi Faraz,

I assume you are talking about the getContentStream call in the CMIS ObjectService.

To your first question.

CMIS WebServices support MTOM streaming mechanism to handle (big) content. The returning CmisContentStreamType object contains a DataHandler you can read into an InputStream.

A Java example.

final DataHandler dataHandler = cmisContentStreamType.getStream();

final StreamingDataHandler sdh = (StreamingDataHandler) dataHandler;

InputStream in = sdh.readOnce();

Using the Atompub binding you can download content by addressing the file name as indicated in the response.

For example

GET /ot-cmis/atom/2000/content/<file_name>?id=<doc_id>

To your second question I quote what I got from our RCS expert Radu.

“From the RCS point of view (CMIS is running inside of RCS), we are supporting HTTP Basic Authentication augmented with “Cookies”. The cookie contains the OTDS ticket.

If each http request made by client contains the HTTP Basic Authentication HTTP header and the cookie, then an automatic re-login will be made by RCS (if the RCS-TTL expires, or if the CS session expires) so that long running CS sessions are possible.

If the client could make WebServices requests, then the problem is similar with that of an ELIB client. We have programming samples for this.

We are supporting now WSSE (Username Token Profile / Binary Token Profile) which can be used by the client if it doesn’t want to use the AuthWS for the first “login” and the OTAuthentication SOAP header for the subsequent requests.”

Stefano

From: eLink Entry: ELS General Forum [mailto:el_general_forum2@elinkkc.opentext.com]
Sent: Dienstag, 8. November 2011 18:49
To: eLink Recipient
Subject: Rendering objectStream response from CMIS

Rendering objectStream response from CMIS

Posted by faraz.i.abbasi@accenture.com (Abbasi, Faraz) On 11/08/2011 12:45 PM

Hello,

Thank you.

[To post a comment, use the normal reply function]
Forum:	ELS General Forum
Content Server:	Knowledge Center

Faraz_Abbasi

Thank you for the reply; it is appreciated. I am not really familiar with AtomPub bindings but I'd like to get more information about this approach.

From your example, it seems like I should be able to write a Java Server Page application that retrieves the getObjectStreamResponse, and then renders that object to the user. Is the AtomPub approach an alternate to the above or used in conjunction?

My idea right now is that we create an auxiliary program outside the web application (which is a COTS product and doesn't seem to natively handle AtomPub) that retrieves the document. The web application can call the auxiliary program through a URL link, and that will be responsible for providing a download link to the user.

Are there any programming samples of the AtomPub binding I can leverage?

Thanks!

Faraz_Abbasi

Another followup - in using the AtomPub binding, I am encountering the following error for any valid value of objectid and filename:

HTTP Status 500 - Unexpected Runtime Exception - type : RUNTIME - code : 10038 - Detailed message : A com.opentext.ecm.services.entlib.ELServiceException occurred on command 'getContentSource' parameters 'variantId : ' objectid' - blobName : ' filename' - offset : '0' - length : '-1'' isSystemException 'true' - Cause message [com.opentext.ecm.services.entlib.ELServiceException: Sending audit event failed!<Fri Nov 18 00:58:27 EST 2011|gscgigdcapmdw02> [{error_namespace=ELService, error_code=SendAuditEvent, error_category=Operation}] (com.opentext.livelink.service.core.LivelinkException: The specified Audit event may not be created via this API.)]

type Status report

message Unexpected Runtime Exception - type : RUNTIME - code : 10038 - Detailed message : A com.opentext.ecm.services.entlib.ELServiceException occurred on command 'getContentSource' parameters 'variantId : ' objectid' - blobName : 'filename' - offset : '0' - length : '-1'' isSystemException 'true' - Cause message [com.opentext.ecm.services.entlib.ELServiceException: Sending audit event failed!<Fri Nov 18 00:58:27 EST 2011|gscgigdcapmdw02> [{error_namespace=ELService, error_code=SendAuditEvent, error_category=Operation}] (com.opentext.livelink.service.core.LivelinkException: The specified Audit event may not be created via this API.)]

description The server encountered an internal error (Unexpected Runtime Exception - type : RUNTIME - code : 10038 - Detailed message : A com.opentext.ecm.services.entlib.ELServiceException occurred on command 'getContentSource' parameters 'variantId : 'objectid' - blobName : 'filename' - offset : '0' - length : '-1'' isSystemException 'true' - Cause message [com.opentext.ecm.services.entlib.ELServiceException: Sending audit event failed!<Fri Nov 18 00:58:27 EST 2011|gscgigdcapmdw02> [{error_namespace=ELService, error_code=SendAuditEvent, error_category=Operation}] (com.opentext.livelink.service.core.LivelinkException: The specified Audit event may not be created via this API.)]) that prevented it from fulfilling this request.

Apache Tomcat/6.0.32

eLink User

Hi Faraz,my code example shows the use of SOAP binding API in Java. The Atompub binding is alternative to SOAP and I don't have a concrete client example for it to provide right away.I don't know which technology/language you are using and what are exactly your needs but if you are writing something in Java or C# I would suggest to use the SOAP binding by generating client stubs from the CMIS WSDLs.Alternatively you could consider using the OpenCmis (http://chemistry.apache.org/) libraries, which support several client technologies (Java, Python, PHP, .NET, ...) making the binding transparent to the client implementation. Or you could just have a look into their code to see how they wrote the Atompub implementation.I'm aware that we'd need some Programming Samples to better support our customers on our CMIS integration. This is on our schedule already.StefanoFrom: eLink Entry: ELS General Forum [mailto:el_general_forum2@elinkkc.opentext.com] Sent: Freitag, 18. November 2011 06:47To: eLink RecipientSubject: RE Rendering objectStream response from CMISRE Rendering objectStream response from CMIS Posted by faraz.i.abbasi@accenture.com (Abbasi, Faraz) On 11-18-2011 00:41 Thank you for the reply; it is appreciated. I am not really familiar with AtomPub bindings but I'd like to get more information about this approach.>From your example, it seems like I should be able to write a Java Server Page application that retrieves the getObjectStreamResponse, and then renders that object to the user. Is the AtomPub approach an alternate to the above or used in conjunction? My idea right now is that we create an auxiliary program outside the web application (which is a COTS product and doesn't seem to natively handle AtomPub) that retrieves the document. The web application can call the auxiliary program through a URL link, and that will be responsible for providing a download link to the user.Are there any programming samples of the AtomPub binding I can leverage?Thanks!________________________________________[To post a comment, use the normal reply function] Topic: Rendering objectStream response from CMIS Forum: ELS General Forum Content Server: Knowledge Center

eLink User

Hi Faraz,this happens typically when the file \module\elservice_10_2_1\ELAuditEventTypes.xml is not correctly referenced in the \config\opentext.ini.Please make sure that the configuration entry AuditEventsConfig points to the right file path.It looks like you upgraded the elservice module and then removed the old one. Unfortunately the reference in the opentext.ini is not automatically changed.I hope this helps.StefanoFrom: eLink Entry: ELS General Forum [mailto:el_general_forum2@elinkkc.opentext.com] Sent: Freitag, 18. November 2011 07:27To: eLink RecipientSubject: RE Rendering objectStream response from CMISRE Rendering objectStream response from CMIS Posted by faraz.i.abbasi@accenture.com (Abbasi, Faraz) On 11-18-2011 01:19 Another followup - in using the AtomPub binding, I am encountering the following error for any valid value of objectid and filename: HTTP Status 500 - Unexpected Runtime Exception - type : RUNTIME - code : 10038 - Detailed message : A com.opentext.ecm.services.entlib.ELServiceException occurred on command 'getContentSource' parameters 'variantId : ' objectid' - blobName : ' filename' - offset : '0' - length : '-1'' isSystemException 'true' - Cause message [com.opentext.ecm.services.entlib.ELServiceException: Sending audit event failed! [{error_namespace=ELService, error_code=SendAuditEvent, error_category=Operation}] (com.opentext.livelink.service.core.LivelinkException: The specified Audit event may not be created via this API.)]________________________________________type Status reportmessage Unexpected Runtime Exception - type : RUNTIME - code : 10038 - Detailed message : A com.opentext.ecm.services.entlib.ELServiceException occurred on command 'getContentSource' parameters 'variantId : ' objectid' - blobName : 'filename' - offset : '0' - ! length : '-1'' isSystemException 'true' - Cause message [com.opentext.ecm.services.entlib.ELServiceException: Sending audit event failed! [{error_namespace=ELService, error_code=SendAuditEvent, error_category=Operation}] (com.opentext.livelink.service.core.LivelinkException: The specified Audit event may not be created via this API.)]description The server encountered an internal error (Unexpected Runtime Exception - type : RUNTIME - code : 10038 - Detailed message : A com.opentext.ecm.services.entlib.ELServiceException occurred on command 'getContentSource' parameters 'variantId : 'objectid' - blobName : 'filename' - offset : '0' - ! length : '-1'' isSystemException 'true' - Cause message [com.opentext.ecm.services.entlib.ELServiceException: Sending audit event failed! [{error_namespace=ELService, error_code=SendAuditEvent, error_category=Operation}] (com.opentext.livelink.service.core.LivelinkException: The specified Audit event may not be created via this API.)]) that prevented it from fulfilling this request.________________________________________Apache Tomcat/6.0.32 ________________________________________[To post a comment, use the normal reply function] Topic: Rendering objectStream response from CMIS Forum: ELS General Forum Content Server: Knowledge Center

Faraz_Abbasi

Thanks again for the timely response. Our Content Server implementers are looking into this configuration item you mentioned.

Faraz_Abbasi

Hello,

So according to our Content Server configurator, the configuration was correct but we are still encountering the aforementioned error.

If we use the Shortlink for opening the file, can we pass an authentication token in the URL somehow? We can retrieve the Authentication token beforehand, and then use that AuthenticationToken as a parameter to the URL request to the document using the Shortlink. Alternately, is it possible to pass the username/password as parameters to access the content in the link?

I think the AtomPub binding would be the easiest way to go, then the front-end (Siebel) can retrieve the document via URL, assuming we can authenticate from the back-end and not prompt the user for the username/password.

Thank you,

Faraz

Herbert_Bock

Could you please open the Admin Home > System Administration > Administer Event Auditing > Set Auditing Interests. Are event types "AL Create", "AL Read", "AL Update" and "Blob Read" listed there?

eLink User

Hi Faraz,our CMIS implementation runs within the RCS server which supports HTTP 1.1 Basic Authentication with cookies as already mentioned before. There’s no support for tokens in the URL.Assuming you will use the Atompub binding, you would send the basic authentication indicating just user credentials in the very first CMIS Atompub Request. The subsequent response would deliver a cookie containing the OTDS ticket. In further requests you would re-send the user credentials and the cookie. The latter to perform an implicit re-login (and avoid a time consuming brand new login as at the very first time). The former to ensure long running sessions once the cookie expires.For content retrieval you’re supposed to use the atom:content/src attribute indicated in the Atompub response to point to the content stream, again using basic authentication.If you point to Content Server Shortlinks you would pass by the RCS/CMIS layer. I’m not sure this would be a good and working practice since the Content Server has its own authentication token, which has nothing to do with the RCS/CMIS one. Further I don’t believe CS supports tokens in the URL either.Stefano

Faraz_Abbasi

Thank you, I have asked our configurator to look into this.

I still would like to know more about being able to pass authentication parameters. Can this done via AtomPub? If so, can we retrieve the AuthenticationToken in a separate Web Service call and use that AuthenticationToken to authenticate and retrieve the desired document?

Chaitanya Hedge

Hi Herbert,

We are facing the similar issue. I am not seeing AL Create, AL Read and Blob Read in our system. Can you please let me know where this is used and how to make it appear?

Thanks

Chaitanya

Andreas_Probst

Did you install the module Extensions for Enterprise Library in Content Server?

What is the actual problem you're facing?