UDMI / Docs / Guides / Config Nonce
The config nonce is a debugging feature that can be used to track down problems with configuration updates in the context of UDMI cloud services. It’s essentially a unique token that’s inserted into config updates (from the sequencer) that are tracked through the system.
By adding the -vv flag to sequencer, the system will output more stuff and also include a special nonce
parameter to config messages and updates.
If properly enabled, the nonce will show up in the sequencer output, in this case for the specific system config subFolder:
2022-10-05T21:30:58Z TRACE sequencer received config_system_2022-10-05T21:30:58.072Z:
{
"extra_field" : "reset_config",
"metrics_rate_sec" : 600,
"min_loglevel" : 200,
"debug_config_nonce" : 1665005451790,
"testing" : {
"sequence_name" : "reset_config"
},
"timestamp" : "2022-10-05T21:30:58.072Z",
"version" : "1.3.14-85-g61f475b7"
}
And then should immediately be followed by a “promoted” update, where the system update is incorporated into the complete config update:
2022-10-05T21:30:58Z TRACE sequencer received config_update_2022-10-05T21:30:58.133Z:
{
"debug_config_nonce" : 1665005451790,
"system" : {
"min_loglevel" : 200,
"metrics_rate_sec" : 600,
"testing" : {
"sequence_name" : "reset_config"
},
"extra_field" : "reset_config",
"debug_config_nonce" : 1665005451790
},
"timestamp" : "2022-10-05T21:30:58.133Z",
"version" : "1.3.14-85-g61f475b7"
}
The config updates themselves are processed by some cloud functions. The udmi_reflect function receives the sequencer messages, and the udmi_config function handles the config update itself. The logs of these can be searched for the specific nonce to show a more detailed accounting of what is going on:
~/udmi$ gcloud --project=$project_id functions logs read udmi_reflect --sort-by=time_utc --limit=1000 | fgrep 1665005451790
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:55.755 Reflect ZZ-TRI-FECTA AHU-1 config system 1665005451790
From that, you can look up the complete function execution context run:
~/udmi$ gcloud --project=$project_id functions logs read udmi_reflect --sort-by=time_utc --limit=1000 | fgrep igx30b2gw5gg
D udmi_reflect igx30b2gw5gg 2022-10-05 21:30:54.043 Function execution started
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:54.650 Setting GCLOUD_PROJECT to bos-testing-ci
WARNING udmi_reflect igx30b2gw5gg 2022-10-05 21:30:54.748 Warning, estimating Firebase Config based on GCLOUD_PROJECT. Initializing firebase-admin may fail
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:55.518 No FIREBASE_CONFIG defined
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:55.518 Using UDMI version 1.3.14-85-g61f475b7
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:55.634 Fetching registries for us-central1
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:55.636 Fetching registries for europe-west1
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:55.637 Fetching registries for asia-east1
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:55.755 Reflect ZZ-TRI-FECTA AHU-1 config system 1665005451790
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:55.887 Processing results for us-central1
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:56.399 Processing results for europe-west1
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:56.668 Message publish udmi_config {"deviceId":"AHU-1","deviceNumId":"2612218335398339","deviceRegistryId":"ZZ-TRI-FECTA","deviceRegistryLocation":"us-central1","projectId":"bos-testing-ci","subFolder":"system","subType":"config","cloudRegion":"us-central1"}
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:56.668 Fetched 2 registry regions
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:56.668 Processing results for asia-east1
udmi_reflect igx30b2gw5gg 2022-10-05 21:30:56.999 Message 5834149510944859 published to udmi_config.
D udmi_reflect igx30b2gw5gg 2022-10-05 21:30:57.004 Function execution took 2960 ms. Finished with status: ok
The same logic can be applied to the udmi_config function, but there’s a lot more entries in those logs, so you may need to add a specific end-time filter:
~/udmi$ gcloud --project=$project_id functions logs read udmi_config --sort-by=time_utc --limit=1000 --end-time=2022-10-05T21:31:57.004 | fgrep 1665005451790
udmi_config u1az18rg4bh8 2022-10-05 21:30:58.072 Config message ZZ-TRI-FECTA AHU-1 system 1665005451790 {"min_loglevel":200,"metrics_rate_sec":600,"testing":{"sequence_name":"reset_config"},"extra_field":"reset_config","debug_config_nonce":1665005451790}
udmi_config u1az18rg4bh8 2022-10-05 21:30:58.073 command devices/AHU-1/config/system 1665005451790 projects/bos-testing-ci/locations/us-central1/registries/UDMI-REFLECT/devices/ZZ-TRI-FECTA
udmi_config u1az18rg4bh8 2022-10-05 21:30:58.133 Config modify system 86490 2022-10-05T21:30:58.073Z 1665005451790
udmi_config u1az18rg4bh8 2022-10-05 21:30:58.189 command devices/AHU-1/config/update 1665005451790 projects/bos-testing-ci/locations/us-central1/registries/UDMI-REFLECT/devices/ZZ-TRI-FECTA
udmi_config u1az18rg4bh8 2022-10-05 21:30:58.218 Config accepted system 86490 2022-10-05T21:30:58.073Z 1665005451790
For config blocks that have multiple sub-folders, there will be a nonce for each and also at the top level. The top-level one indicates which subFolder was added most recently. Although nominally a timestamp, the numerical ordering of the nonce is not reliable as a source of information.
2022-10-05T21:31:03Z TRACE sequencer received config_update_2022-10-05T21:31:02.950Z:
{
"debug_config_nonce" : 1665005461272,
"pointset" : {
"points" : {
"filter_alarm_pressure_status" : {
"ref" : "BV11.present_value"
},
"filter_differential_pressure_setpoint" : {
"set_value" : 98
},
"filter_differential_pressure_sensor" : {
"ref" : "AV12.present_value"
}
},
"debug_config_nonce" : 1665005461272
},
"system" : {
"min_loglevel" : 200,
"metrics_rate_sec" : 600,
"testing" : {
"sequence_name" : "writeback_states"
},
"debug_config_nonce" : 1665005459267,
"last_start" : "2022-10-05T21:30:45Z"
},
"timestamp" : "2022-10-05T21:31:02.950Z",
"version" : "1.3.14-85-g61f475b7"
}