When selecting "plainURL" mode in the MongoDBConnection Editor, there are "ConnectionURL" and "DatabaseName" can be configured in the configuration page.
If the database name is specified in the "DatabaseName" but not the "ConnectionURL", the test connection could work. But the BW process will fail with the error message as below:
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14:59:34.693 ERROR [Framework Event Dispatcher: Equinox Container: 901bd383-ce7b-0018-1634-875c53fc1d46] c.t.b.thor.runtime.model.Constituent - The following error has occurred for "name: sample1 version: 1.0.0.qualifier bundle name: sample1 " which needs to be resolved.
14:59:34.693 ERROR [Framework Event Dispatcher: Equinox Container: 901bd383-ce7b-0018-1634-875c53fc1d46] c.t.b.thor.runtime.model.Constituent - TIBCO-BW-FRWK-600053: Failed to initialize BW Component [ComponentProcess].
<CausedBy> com.tibco.bw.core.runtime.api.BWEngineException: TIBCO-BW-CORE-500232: Failed to initialize BW Component [ComponentProcess], Application [sample1.application:1.0] due to activity initialization error.
<CausedBy> com.tibco.bw.core.runtime.ActivityInitException: TIBCO-BW-CORE-500618: Failed to initialize the activity [InsertDocument] in process [sample1.Process], module [sample1] due to unexpected activity lifecycle error.
<CausedBy> java.lang.IllegalArgumentException: source can not be null
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The error "source can not be null" happens if the database has not been set in the URL while using "plainURL" mode in the connection resource

Product: TIBCO ActiveMatrix BusinessWorks Plug-in for MongoDB Version: 6.2.1 and previous versions OS: All Supported Operating Systems

Specify the database name in the "ConnectionURL" as below:

mongodb://<user_name>:<password>@<server_name>:<port>/<database_name>?authSource=<auth_database>&connectTimeoutMS=10000&socketTimeoutMS=0&waitQueueTimeoutMS=120000&maxPoolSize=100