Timed out after 30000 ms while waiting for a server that matches WritableServerSelector. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING}]
 at com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting for a server that matches WritableServerSelector. Client view of cluster state is{type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING}]
 at         at com.mongodb.connection.BaseCluster.cr[......]
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