Question Re: File Attachment using gateway in Technology Q&A

File Attachment using gateway

jibin_joy — Tue, 06 Nov 2012 16:02:51 GMT

Hi Everyone,

New scenario: uploading and downloading file using SAP Netweaver Gateway .

Dont know how to solve this one .

I like to have ur valuable suggestion and Advice for this requirement.

Thanks in Advance,

Regards,

Jibin JOy

Re: File Attachment using gateway

Former Member — Thu, 08 Nov 2012 00:57:04 GMT

I have the same question and I am looking forward someone could give some hints on this.

Re: File Attachment using gateway

former_member182048 — Thu, 08 Nov 2012 05:55:45 GMT

Hi Jibin / Jessie

TLDR The answer depends on the requirement. There are a few ways I can think of to achieve Uploading and Downloading files with Gateway services. The most efficient way is to provide URL links to the file content, then have separate client calls stream the data to and from the server via the Gateway service or maintain the data by methods independent of the Gateway service .

The OData protocol enables you to define data feeds that also make binary large object (BLOB) data, such as photos, videos, and documents available to client applications that consume the OData feeds. For performance reasons it is not good practice to return the BLOB's in the feed themselves, rather call the Binary Data, known as a Media Resource separately via a Media Link Entry present in the feed.

eg.

Example of using Media Links to retrieve Workflow attachments. Workflow Services -> Media Links - see

DPC: /IWWRK/CL_MGW_RT_WORKFLOW

MPC: /IWWRK/CL_MGW_MED_WORKFLOW

If you have access to the the Electronic Medical Record Gateway services you can see both how to use both Media Links and Binary fields in the feed

/MEMR/CL_ET_ATTACHMENT_HANDLER

/MEMR/CL_ET_DOCUMENT_HANDLER

To support streaming in Gateway services,the DPC has the following methods :

/IWBEP/IF_MGW_APPL_SRV_RUNTIME~CREATE_STREAM

/IWBEP/IF_MGW_APPL_SRV_RUNTIME~GET_STREAM

/IWBEP/IF_MGW_APPL_SRV_RUNTIME~UPDATE_ENTITY

/IWBEP/IF_MGW_APPL_SRV_RUNTIME~DELETE_STREAM

The first half of this document explains how it should work OData support for streams

The only full CRUD example i could find is

/IWBEP/CL_MGW_RT_SFLIGHT local class LCL_CARRIER->Create/Update/Delete_Stream, however this code doesn't seem active or recent.

Hope it helps.

Cheers

John P

Re: File Attachment using gateway

jibin_joy — Thu, 08 Nov 2012 07:43:38 GMT

Hi John,

How /IWBEP/IF_MGW_APPL_SRV_RUNTIME~GET_STREAM method is invoked I mean can u provide me the sample url to invoke this method.

Thanks,

Jibin Joy

Re: File Attachment using gateway

former_member182048 — Thu, 08 Nov 2012 09:46:42 GMT

Hi Jibin

As an example of how to call GET_STREAM for a carrier

call the following to get the entity

http://server:port/sap/opu/odata/IWFND/RMTSAMPLEFLIGHT/CarrierCollection('AA')

in the payload you will see a couple of links

if you do a GET

/sap/opu/odata/IWFND/RMTSAMPLEFLIGHT/CarrierCollection('AA')/$value

set header accept = image/gif

you should see that GET_STREAM is called.

likewise if you do a PUT on

/sap/opu/odata/IWFND/RMTSAMPLEFLIGHT/CarrierCollection('AA')/$value

set header content-type = image/gif

you should be able to update the image calling UPDATE_STREAM

**first you need to setup a default virus profile

UPDATE:

Transaction /IWFND/VIRUS_SCAN here you can set or turn off Virus Scan

Also attached screen shot for CREATE_STREAM for Carrier, need to call the collection with the right headers and a slug

Cheers

JSP

Re: File Attachment using gateway

jibin_joy — Fri, 09 Nov 2012 07:10:58 GMT

Hi John,

It was very helpful info . It's working properly .

But i am facing some pblm during SEGW class generation .

Currently using SAP Netwear Gateway SP5

based on the document http://help.sap.com/saphelp_gateway20sp04/helpdata/en/67/d2c38221984d8eb46b8a8d983407b9/content.htm

for media type setting

* setting a data object as media type means that it gets a special semantic by having a url and allows streaming etc.

lo_data_object->set_is_media( ).

for mime type information setting

* must be set when data object is a media type to mark the property which represents the mime type information

lo_property->set_fc_target_path( iv_keep_in_content = abap_true iv_fc_target_path = gcs_fc_target_path - content/@type ).

but during generating run-time object the above code is not generate.

for running i manually added above code in generated class .

I need ur valuable suggestion to resolve this pblm.

Thanks in advance

Regards,

Jibin Joy

Re: File Attachment using gateway

former_member182048 — Fri, 09 Nov 2012 09:11:38 GMT

Hi Jibin

Thanks for the link to the Media Link help document, I never saw that before, could have save me a lot of time attempting to write something similar.

I am using a SP4 system and the Gateway builder doesn't have some of the features shown in your screenshots. Given you are on SP5 suggests you are a customer and entitled to raise an OSS note, you could either live the workaround or raise a Note.

Cheers

John P

Re: File Attachment using gateway

jibin_joy — Wed, 14 Nov 2012 07:28:31 GMT

Hi John,

Do u know how to set the filename since wht were file we are downloading will have same name "$value" but i want my file name like doc1.doc so that it will be more flexible to open that downloaded files

Thanks in Advance,

Regards,

Jibin Joy

Re: File Attachment using gateway

jibin_joy — Wed, 14 Nov 2012 10:16:33 GMT

Hi John,

For setting up the file name .

we have to manually add one header content

DATA ls_temp TYPE LINE OF tihttpnvp.

ls_temp-name = 'Content-Disposition'.

ls_temp-value = 'inline; filename="doc2.doc"'.

APPEND ls_temp TO ct_headers.

Plz Ref http://www.ietf.org/rfc/rfc1806.txt

Regards,

Jibin Joy

Re: File Attachment using gateway

former_member182048 — Wed, 14 Nov 2012 12:33:04 GMT

thanks will try.

Re: File Attachment using gateway

jibin_joy — Fri, 16 Nov 2012 16:38:24 GMT

Hi John,

For ur Future ref..........

Based on my observation the following might be a problem for streaming and i dont know whether it is right or not . just try it whenever got time.

1. Create Stream

Request Body :

------WebKitFormBoundary2BKGSHLTKayEh8qt

Content-Disposition: form-data; name="fileUpload"; filename="text1.txt"

Content-Type: text/plain

-----file stream data ----

------WebKitFormBoundary2BKGSHLTKayEh8qt--

In create stream method, file stream data is not properly fetched ....

If u observe media resource variable in method , will contain all the data from top to bottom (including ------WebKitFormBoundary2BKGSHLTKayEh8qt ......... ) as shown above .

and dont know show to fetch the uploaded file name also.

2. Update Stream

Throws an error for update stream

Error :

" The server is refusing to process the request because the entity has a unsupported format "

Class : /IWCOR/CL_DS_PROC_DISPATCHER

Method : PROCESS_ENTITY

Content :

validate_content_type(

it_supported_format = lt_supported_format
iv_content_type = io_request_entity->get_header_field( if_http_header_fields=>content_type ) ).

io_request_entity>get_header_field( if_http_header_fields=>content_type )

The above code returns "multipart/form-data"

and lt_supported_format contain following value

application/atom+xml

application/atom+xml;type=entry

application/json

application/json;odata=verbose

application/xml

application/json

And validate_content_type method check Request Header ("multipart/form-data") in lt_supported_format.

if not found above error is thrown.

Regards,

Jibin Joy

Re: File Attachment using gateway

former_member182048 — Fri, 16 Nov 2012 23:14:04 GMT

Hi Jibin

Just to clarify what the issue is.

You are using a browser and trying to upload a file as a stream using an input form

i'm guess something like

You are expecting Content-Type: text/plain to be sent

but the browser is wrapping your file in a Content-Type: multipart/form-data; and Gateway doesn't support this Content-Type

You are wanting to know how to send only Content-Type: text/plain from the browser.

I guess you could try changing the enctype of the form or better yet use the Filereader API to get the BLOB and then do an XHR to the gateway service. See http://www.html5rocks.com/en/tutorials/file/dndfiles/ should give you some ideas of what is possible using webkit.

Cheers

JSP

Re: File Attachment using gateway

jibin_joy — Sat, 17 Nov 2012 04:33:08 GMT

Hi John,

My scenario is simple trying to uploading any file it can be pdf , image or just a text.

</form>

this one is parsing fine but we have to add one more header X-Requested-With=XMLHttpRequest until then it will throw an error. but dont know how to set header during form submit . so we have to introduce one more object in between like servlet which will add header and pass to gateway.

For testing purpose i am using chrome rest client tool as u mentioned in past post .

Based on my observation the browser is wrapping file in a Content-Type: multipart/form-data and it support also but it is not parsing the file stream properly, as it does for multipart/mixed ( it fetch each request from batch request ) .

Hope i am clear with my scenario .

Regards,

Jibin Joy

Re: File Attachment using gateway

Former Member — Fri, 02 Aug 2013 06:29:17 GMT

Hi Jibin,

Are you able to read the attachment as per the link,

http://help.sap.com/saphelp_gateway20sp04/helpdata/en/67/d2c38221984d8eb46b8a8d98

1. I am trying to read a pic from the application server as in this document.

2. I have created a entity type with few fields for emp details and one more field for Mime Type, like yours.

3.And while mapping a data source, I have mapped except mime,as we are coding in EXT class , what should i map here.

4.I am getting "Property 'mimeType' of Data Object 'EmployeeData' has no type assigned." error. Please let me know how you proceeded with next steps.

Thanks and Regards,

Re: File Attachment using gateway

jibin_joy — Mon, 23 Sep 2013 07:47:20 GMT

Hi Peter Dinesh ,

still now i didn't tested File attachment using RFC ..... for time being create temp attribute in RFC FM then map to that attribute .

and in create , update or get stream we can u mention actual mine type

Regards,

Jibin Joy

Re: File Attachment using gateway

Former Member — Mon, 30 Sep 2013 11:49:16 GMT

Dear Friends,

I am facing a scenario wherein for a header(1st Entity) I need to upload multiple attachments(2nd Entity).

I have established an association and navigation between 2 entities. I understand that GET_STREAM/CREATE_STREAM are called based on operation via HTTP.

My issues is, how can I call the CREATE_STREAM or GET_STREAM multiple times for an entity ?.

Regards,

Venkat

Re: File Attachment using gateway

Former Member — Wed, 07 May 2014 14:30:10 GMT

Hi Jibin,

Did you find a solution to your problem? I am facing the exact issue with the file surrounded by webkitformboundary when it is sent to the CREATE_STREAM method. The browser is IE8, so not much can be done here.

Regards

Neha

Re: File Attachment using gateway

jibin_joy — Wed, 07 May 2014 15:09:07 GMT

Hi Neha,

Can i know which Service Package ur using .. If possible can u post ur UI Code in my mail ID .

Regards,

Jibin Joy

Re: File Attachment using gateway

Former Member — Wed, 07 May 2014 15:27:21 GMT

Hi Jibin,

NW 7.31 SP06. Could you send your email id? Thanks!

Best Regards

Neha

Re: File Attachment using gateway

Former Member — Tue, 13 May 2014 11:02:57 GMT

Hello John,

I want to upload a file like PDF or DOC from ui5 to backend, using oData.

I created a gateway service.

I know that I must redefine create_stream method, but I don't know how to do that.

Do you have an example, how to write this method in abap?

Thank you,

Mari