Documentation

Working with Workflow Context

Workflows in Liferay are used as approval processes. At each step of the process, the workflow has certain data that’s available in a Map<String, Serializable> object referred to in your scripts and custom code as workflowContext. The workflow context information is important to the proper functionality of Liferay’s workflow engine. Understanding it can help you determine how best to use it in your custom code and workflow scripts.

For example, with workflow context you can

Note

Use ServiceContext to set attributes in contexts where a workflowContext is not available. For example, if your custom code calls BlogsEntryLocalService#addEntry, you must provide a ServiceContext object to it. You can use ServiceContext#setAttribute to pass in data that you want to access in the workflow.

There are some important things to be aware of when working with workflowContext:

  • It must be modifiable, therefore it isn’t thread safe. Caution is advised in parallel execution contexts.

    For example, in a workflow with a fork node, updating the workflowContext in both forks of the workflow is not recommended.

  • Its first type parameter (the key for the attribute) is a String. This is used to look up the value stored in the second attribute.

  • Its second type parameter (the value for each attribute) is a Serializable because it’s stored in the database. This ensures that it’s accessible at every step of the workflow.

To print the workflow context keys and values in any workflow node, you can add a script action like this one:

<actions>
    <action>
        <name>print-workflow-context</name>
        <script>
            <![CDATA[
            for (Map.Entry<String, Serializable> mapEntry :
                workflowContext.entrySet()) {
                    out.println(mapEntry.getKey(), mapEntry.getValue());
            }
            ]]>
        </script>
        <script-language>groovy</script-language>
        <execution-type>onEntry</execution-type>
    </action>
</actions>

When the node is entered, output is printed to the log:

entryType, Blogs Entry
companyId, 37401
entryClassPK, 40226
entryClassName, com.liferay.blogs.model.BlogsEntry
groupId, 37441
taskComments, 
userPortraitURL, /image/user_portrait?img_id=0&img_id_token=IpLU58ogLTDf%2FDIfo8Ukg0YxiUE%3D&t=1626283728181
serviceContext, [email protected]
userId, 37448
url, http://localhost:8080/group/guest/~/control_panel/manage?p_p_id=com_liferay_blogs_web_portlet_BlogsAdminPortlet&p_p_lifecycle=0&p_p_state=maximized&_com_liferay_blogs_web_portlet_BlogsAdminPortlet_mvcRenderCommandName=%2Fblogs%2Fview_entry&_com_liferay_blogs_web_portlet_BlogsAdminPortlet_entryId=40226&p_p_auth=rRDR0ncV
userURL, http://localhost:8080/web/test

Accessing Workflow Context Attributes in Workflow Definitions

To access workflowContext attributes form a <script>, retrieve them with the Map#get method:

import com.liferay.portal.kernel.workflow.WorkflowConstants;

String className = (String)workflowContext.get(WorkflowConstants.CONTEXT_ENTRY_CLASS_NAME);

The above example retrieves a String, but some of the workflowContext attributes must be used as longs (for example, when passed as method parameters). The GetterUtil utility class helps with this:

import com.liferay.portal.kernel.util.GetterUtil;
import com.liferay.portal.kernel.workflow.WorkflowConstants;

long classPK = GetterUtil.getLong((String)workflowContext.get(WorkflowConstants.CONTEXT_ENTRY_CLASS_PK));

Using the WorkflowConstants object fields helps avoid error-prone String literals. The workflowContext fields are all prefixed with CONTEXT (e.g., CONTEXT_COMPANY_ID).

Setting Workflow Context Attributes in Workflow Definitions

To set attributes into the workflowContext, use the Map#put method. This example sets the assetTitle:

import com.liferay.asset.kernel.model.AssetRenderer;
import com.liferay.portal.kernel.util.GetterUtil;
import com.liferay.portal.kernel.workflow.WorkflowConstants;
import com.liferay.portal.kernel.workflow.WorkflowHandler;
import com.liferay.portal.kernel.workflow.WorkflowHandlerRegistryUtil;

String className = (String)workflowContext.get(WorkflowConstants.CONTEXT_ENTRY_CLASS_NAME);

WorkflowHandler workflowHandler = WorkflowHandlerRegistryUtil.getWorkflowHandler(className);

long classPK = GetterUtil.getLong((String)workflowContext.get(WorkflowConstants.CONTEXT_ENTRY_CLASS_PK));

AssetRenderer assetRenderer = workflowHandler.getAssetRenderer(classPK);

String assetTitle = assetRenderer.getAssetObject().getTitle();

workflowContext.put("assetTitle", assetTitle);

Tip

The above code works only if the asset has a getTitle method (for example, JournalArticle).

Setting Service Context Attributes for Access in Workflow Definitions

Sometimes in your custom Java code, you must pass information to the workflow definition but there’s no workflowContext to pass through. For example, if you’re writing code that adds Blogs Entries, you can call one of the BlogsEntryLocalService#addEntry methods. Even though workflowContext isn’t a parameter in these methods, ServiceContext is. Add a new attribute to the service context:

serviceContext.setAttribute("customAttributeKey", "customAttributeValue");

To get the attribute in the workflow definition, retrieve the ServiceContext from the workflowContext, the get the attribute using its key:

import com.liferay.portal.kernel.service.ServiceContext;
import com.liferay.portal.kernel.workflow.WorkflowConstants;

ServiceContext serviceContext = (ServiceContext)workflowContext.get(WorkflowConstants.CONTEXT_SERVICE_CONTEXT);

serviceContext.getAttribute("customAttributeKey");