Hello, The state endpoints, on master and agent, currently serialize two binary data fields in the ExecutorInfo and TaskInfo objects. These fields are set by frameworks; and Mesos does not inspect their values.
The data fields can be found in the state JSON blobs: /master/state -> frameworks[*].executors[*].data /slave/state -> frameworks[*].(executors|completed_executors)[*].(tasks|queued_tasks|completed_tasks)[*].data *Problem:* The state endpoints are JSON-ified in a non-standard way (i.e. not via our normal Protobuf-to-json methods). When we serialize the binary "data" fields, the binary is dumped as a string, as is. The resulting JSON may not be valid if the binary data includes random bytes (i.e. not unicode). Most JSON parsers will error on the state endpoints in this case. *Proposed solution *(and breaking change)*:* Simple -- remove the "data" fields from the state endpoints. (And only from the state endpoints. The ExecutorInfo and TaskInfo objects will not change.) *Question:* We believe that frameworks/tools do not rely on retrieving the "data" fields from the state endpoints. Is there any framework/tool that retrieves the "data" field from the state endpoints? And if so, is it critical to how the framework/tool works? More details here: https://issues.apache.org/jira/browse/MESOS-3771 Thanks, ~Joseph