topic Re: Access uploaded file in Groovy Script in Alfresco Forum

Access uploaded file in Groovy Script

jvaidya — Thu, 01 Jun 2017 19:24:40 GMT

I'm trying to Base64 encode a file that a user uploads in an Activiti form, and then save the resulting encoding as a string to be accessed by other parts of the business process. I thought a Groovy Script in a Script task would be the best way to do this. How do I access the file in the script? Wou

Re: Access uploaded file in Groovy Script

gdharley — Thu, 01 Jun 2017 22:14:27 GMT

Nope, When you upload a file it is registered as related content (Enterprise Edition) or as an attachment (Community Edition).

You will need to use the relatedContentService to retrieve the uploaded files for the process instance (Enterprise Edition).
More details here:

if using Community Edition you can get to the attachments you use taskService.getTaskAttachments(taskid).

This will return a list of atachments from which you can retrieve the content.

Greg

‌

Re: Access uploaded file in Groovy Script

jvaidya — Fri, 02 Jun 2017 15:43:45 GMT

Thanks Greg! Very helpful! I tried calling the API from a Script Task, but I can't use jQuery or vanilla JavaScript AJAX calls. The error I get from Activiti is:

Caused by: <eval>:5 ReferenceError: "XMLHttpRequest" is not defined

How do I access this API if I can't use XML Http Requests?

EDIT: I tried following this : What is the best way to call REST API from Activiti? Can I use JavaScript's URL redirection? but I get an "'importPackage' is not defined" error.

Re: Access uploaded file in Groovy Script

gdharley — Fri, 02 Jun 2017 17:09:43 GMT

Hi Jay,

Script tasks actually run on the server side, even though they use Javascript (via embedded Nashorn/Rhino engine) or groovy.

Therefore you dont need to access the Ajax request.

Look up script tasks here: Activiti User Guide - Script Task

Re: Access uploaded file in Groovy Script

jvaidya — Fri, 02 Jun 2017 18:10:28 GMT

How do I access the file using relatedContentService? The link you pointed me to in the original answer uses REST API calls, so I got a little confused! Sorry about that.

Can you point me to the documentation for relatedContentService?

Re: Access uploaded file in Groovy Script

gdharley — Fri, 02 Jun 2017 18:20:48 GMT

Unfortunately there is no documentation on related content service.
You can check for example use here:

Greg

Re: Access uploaded file in Groovy Script

jvaidya — Fri, 02 Jun 2017 18:27:22 GMT

Hi Greg,

Can you do something like this in a script task, or would you have to use a service task? The example you pointed me to seems to use Java, but script tasks can only take JavaScript or Groovy, correct?

Thanks,

Jay

Re: Access uploaded file in Groovy Script

gdharley — Fri, 02 Jun 2017 18:38:03 GMT

Yes, it is java code, but if you set the script task language to groovy then you can effectively write java code in a script task.

Obviously if the code is complex you would use a service task, but for simple things like pulling the instance/task attachments it is only a few lines of code (<10) so a script task if ok.
The only real downside to a script task is the fact that you cannot debug your code and dont have the toot support you would have with a java IDE.

Greg

Re: Access uploaded file in Groovy Script

jvaidya — Fri, 02 Jun 2017 18:52:10 GMT

Thanks Greg. I'm a little lost without documentation, so not sure how to use relatedContentService. Would something like this work?

fileVar = "content"

file = relatedContentService.getFieldContentForProcessInstance( execution.getProcessInstanceId(), fileVar, 1, 0).getContent(); <- what format would file be in and what methods of relatedContentService do I use?

is = file.getStream() <- Another questionable line
val = is.read()
output = ""
while(val != -1){
output += val
}
execution.setVariable('raw', output)

Re: Access uploaded file in Groovy Script

gdharley — Fri, 02 Jun 2017 20:48:24 GMT

Try this in a groovy script task.

import com.activiti.service.runtime.RelatedContentService;
import com.activiti.service.runtime.RelatedContentStreamProvider;
import com.activiti.domain.runtime.RelatedContent;
import java.io.InputStream;
import org.apache.commons.io.IOUtils;
import java.nio.charset.StandardCharsets;
String fileVariableName = "myFile";
List<RelatedContent> contentList = relatedContentService.getFieldContentForProcessInstance(execution.getProcessInstanceId(), fileVariableName, 1, 0).getContent();
RelatedContent content = contentList.get(0);
out.println("GDH :" + content.getName());
InputStream is = relatedContentStreamProvider.getContentStream(content);
String result = IOUtils.toString(is, StandardCharsets.UTF_8);
out.println("GDH:" + result);

Apologies but ALfresco has not documented any of these services.

Greg

‌

Re: Access uploaded file in Groovy Script

jvaidya — Fri, 02 Jun 2017 21:04:39 GMT

Thanks so much that's really helpful! Unfortunately, I'm getting this error:

problem evaluating script: javax.script.ScriptException: groovy.lang.MissingPropertyException: No such property: relatedContentService for class: Script1

Any thoughts?

Re: Access uploaded file in Groovy Script

gdharley — Fri, 02 Jun 2017 21:15:08 GMT

No idea, I built this just now in my 1.6.1 environment and it runs ok (Process Services 1.6.1 on Tomcat).

Re: Access uploaded file in Groovy Script

jvaidya — Tue, 06 Jun 2017 17:14:57 GMT

Managed to solve this issue! We had to change the activiti-app.properties configuration file to set:

# Beans whitelisting
beans.whitelisting.enabled=false

# EL whitelisting
el.whitelisting.enabled=false

Re: Access uploaded file in Groovy Script

gdharley — Fri, 09 Jun 2017 14:36:22 GMT

Ahh yes, Alfresco in their infinite wisdom decided to lock down security by disabling access to beans without telling anyone in 1.6.

Should have thought of that.

Greg

#bp3