sending an initial corrupt telemetry message to a child device prevents device being registered

[reubenmiller]

Describe the bug

If an event with an invalid payload is published to the thin-edge.io broker, it prevents the child device from being registered with Cumulocity IoT.

If the user then fixed the event payload, and publishes the event again, the event is rejected by Cumulocity IoT as the device has not been registered (due to the absent 101 SmartREST message).

The following error is seen on the second publishing of the corrected thin-edge.io event message:

[c8y/error] {"messageId":190,"error":"general/internalError","message":"Current device is not the owner of the given source null","info":"https://cumulocity.com/guides/reference/rest-implementation"}

To Reproduce

1. Create an event for a new child device. The event is ill-formed (e.g. invalid json)

   tedge mqtt pub 'te/device/mytest///e/something' '{corrupt fragment, "text":"my event"}'

   If you have subscribed to the # topic locally, you should see an error message about the ill-formed event payload

   [te/device/mytest///e/something] {corrupt fragment, "text":"my event"}
   [te/errors] Parsing of event message received on topic: te/device/mytest///e/something failed due to error: key must be a string at line 1 column 2. Snipped payload: {corrupt fragment, "text":"my event"}
   

2. Fix the ill-formed event payload, and publish again

   tedge mqtt pub 'te/device/mytest///e/something' '{"text":"my event"}'
   

   On the # topic, thin-edge.io will attempt to create an event, but without registering the child device first.

   [te/device/mytest///e/something] {"text":"my event"}
   [c8y/event/events/create] {"type":"something","time":"2024-05-22T06:12:43.254635699Z","text":"my event","externalSource":{"externalId":"rpi4-d83add90fe56:device:mytest","type":"c8y_Serial"}}
   [c8y/error] {"messageId":190,"error":"general/internalError","message":"Current device is not the owner of the given source null","info":"https://cumulocity.com/guides/reference/rest-implementation"}
   

Expected behavior

• Invalid telemetry data messages should not prevent the registration of a device in Cumulocity IoT

Screenshots

Environment (please complete the following information):

Property	Value
OS [incl. version]	Poky (Yocto Project Reference Distro) 4.0.18 (kirkstone)
Hardware [incl. revision]	Raspberry Pi 4 Model B Rev 1.5
System-Architecture	Linux rpi4-d83add90fe56 5.15.92-v8 #1 SMP PREEMPT Wed Feb 8 16:47:50 UTC 2023 aarch64 GNU/Linux
thin-edge.io version	tedge 1.0.1

Additional context

entity store: cat /etc/tedge/.tedge-mapper-c8y/entity_store.jsonl

The internal entity store shows the mytest child device has been recorded, however a child device registration message (c8y/s/us 101) was not sent to Cumulocity IoT.

{"version":"1.0"}
{"topic":{"name":"te/device/main///twin/c8y_Agent"},"payload":"{\"name\":\"thin-edge.io\",\"url\":\"https://thin-edge.io\",\"version\":\"1.0.1\"}","qos":1,"retain":true}
{"topic":{"name":"te/device/main/service/tedge-mapper-c8y"},"payload":"{\"@id\":\"rpi4-d83add90fe56:device:main:service:tedge-mapper-c8y\",\"@parent\":\"device/main//\",\"@type\":\"service\",\"name\":\"tedge-mapper-c8y\",\"type\":\"service\"}","qos":1,"retain":true}
{"topic":{"name":"te/device/main/service/mosquitto-c8y-bridge"},"payload":"{\"@id\":\"rpi4-d83add90fe56:device:main:service:mosquitto-c8y-bridge\",\"@parent\":\"device/main//\",\"@type\":\"service\",\"name\":\"mosquitto-c8y-bridge\",\"type\":\"service\"}","qos":1,"retain":true}
{"topic":{"name":"te/device/main/service/tedge-agent"},"payload":"{\"@id\":\"rpi4-d83add90fe56:device:main:service:tedge-agent\",\"@parent\":\"device/main//\",\"@type\":\"service\",\"name\":\"tedge-agent\",\"type\":\"service\"}","qos":1,"retain":true}
{"topic":{"name":"te/device/main/service/tedge-mapper-collectd"},"payload":"{\"@id\":\"rpi4-d83add90fe56:device:main:service:tedge-mapper-collectd\",\"@parent\":\"device/main//\",\"@type\":\"service\",\"name\":\"tedge-mapper-collectd\",\"type\":\"service\"}","qos":1,"retain":true}
{"topic":{"name":"te/device/main///twin/c8y_Hardware"},"payload":"{\"model\":\"Raspberry Pi 4 Model B Rev 1.5\",\"revision\":\"BCM2835-d03115\",\"serialNumber\":\"1000000044d70329\",\"sysClockSync\":\"no\"}","qos":1,"retain":true}
{"topic":{"name":"te/device/main///twin/device_OS"},"payload":"{\"arch\":\"aarch64\",\"displayName\":\"Poky (Yocto Project Reference Distro) 4.0.18 (kirkstone)\",\"family\":\"GNU/Linux\",\"hostname\":\"rpi4-d83add90fe56\",\"kernel\":\"#1 SMP PREEMPT Wed Feb 8 16:47:50 UTC 2023\",\"sysClockSync\":\"no\",\"version\":\"4.0.18\"}","qos":1,"retain":true}
{"topic":{"name":"te/device/main///twin/c8y_Firmware"},"payload":"{\"name\":\"core-image-tedge-rauc\",\"updated\":\"Tue May 21 22:17:11 UTC 2024\",\"version\":\"20240521.1820\"}","qos":1,"retain":true}
{"topic":{"name":"te/device/mytest//"},"payload":"{\"@id\":\"rpi4-d83add90fe56:device:mytest\",\"@type\":\"child-device\",\"name\":\"mytest\"}","qos":1,"retain":true}

Workaround

1. Edit the /etc/tedge/.tedge-mapper-c8y/entity_store.jsonl file, and remove the message matching the erroneous child device
2. Restart the mapper

   sudo systemctl restart tedge-mapper-c8y
   

[gligorisaev]

QA has tested the bug and it's not reproducable anymore