Breaking change: Kibana fails to start due to invalid length of xpack.reporting.encryptionKey

[piotrp]

Kibana version:
7.8.0

Elasticsearch version:
7.8.0

Server OS version:
Ubuntu 16.04

Browser version:
-

Browser OS version:
-

Original install method (e.g. download page, yum, from source, etc.):
deb package

Describe the bug:
Kibana fails to start: Error: [config validation of [xpack.reporting].encryptionKey]: value has length [20] but it must have a minimum length of [32]

Steps to reproduce:

1. Set short xpack.reporting.encryptionKey in kibana.yml
2. sudo systemctl kibana restart

Expected behavior:
Value passes validation

Screenshots (if relevant):
-

Errors in browser console (if relevant):
-

Provide logs and/or server output (if relevant):

Jul 25 21:23:01 test-host systemd[1]: Started Kibana.
Jul 25 21:23:04 test-host kibana[18650]: {"type":"log","@timestamp":"2020-07-25T19:23:04Z","tags":["warning","plugins-discovery"],"pid":18650,"message":"Expect plugin \"id\" in camelCase, but found: apm_oss"}
Jul 25 21:23:04 test-host kibana[18650]: {"type":"log","@timestamp":"2020-07-25T19:23:04Z","tags":["warning","plugins-discovery"],"pid":18650,"message":"Expect plugin \"id\" in camelCase, but found: triggers_actions_ui"}
Jul 25 21:23:09 test-host kibana[18650]: {"type":"log","@timestamp":"2020-07-25T19:23:09Z","tags":["fatal","root"],"pid":18650,"message":"{ Error: [config validation of [xpack.reporting].encryptionKey]: value has length [20] but it must have a minimum length of [32].\n    at ObjectType.validate (/usr/share/kibana/node_modules/@kbn/config-schema/target/out/types/type.js:61:19)\n    at ConfigService.validateAtPath (/usr/share/kibana/src/core/server/config/config_service.js:188:19)\n    at MapSubscriber.getDistinctConfig.pipe.config [as project] (/usr/share/kibana/src/core/server/config/config_service.js:196:81)\n    at MapSubscriber._next (/usr/share/kibana/node_modules/rxjs/internal/operators/map.js:49:35)\n    at MapSubscriber.Subscriber.next (/usr/share/kibana/node_modules/rxjs/internal/Subscriber.js:66:18)\n    at DistinctUntilChangedSubscriber._next (/usr/share/kibana/node_modules/rxjs/internal/operators/distinctUntilChanged.js:69:30)\n    at DistinctUntilChangedSubscriber.Subscriber.next (/usr/share/kibana/node_modules/rxjs/internal/Subscriber.js:66:18)\n    at MapSubscriber._next (/usr/share/kibana/node_modules/rxjs/internal/operators/map.js:55:26)\n    at MapSubscriber.Subscriber.next (/usr/share/kibana/node_modules/rxjs/internal/Subscriber.js:66:18)\n    at ReplaySubject._subscribe (/usr/share/kibana/node_modules/rxjs/internal/ReplaySubject.js:76:28)\n    at ReplaySubject.Observable._trySubscribe (/usr/share/kibana/node_modules/rxjs/internal/Observable.js:44:25)\n    at ReplaySubject.Subject._trySubscribe (/usr/share/kibana/node_modules/rxjs/internal/Subject.js:102:51)\n    at ReplaySubject.Observable.subscribe (/usr/share/kibana/node_modules/rxjs/internal/Observable.js:30:22)\n    at MapSubscriber.shareReplayOperation (/usr/share/kibana/node_modules/rxjs/internal/operators/shareReplay.js:44:32)\n    at Observable.subscribe (/usr/share/kibana/node_modules/rxjs/internal/Observable.js:25:31)\n    at MapOperator.call (/usr/share/kibana/node_modules/rxjs/internal/operators/map.js:32:23)\n  cause:\n   { Error: value has length [20] but it must have a
Jul 25 21:23:09 test-host kibana[18650]: minimum length of [32].\n       at StringType.onError (/usr/share/kibana/node_modules/@kbn/config-schema/target/out/types/type.js:91:20)\n       at module.exports.internals.Any.Type.schema.error (/usr/share/kibana/node_modules/@kbn/config-schema/target/out/types/type.js:51:53)\n       at finish (/usr/share/kibana/node_modules/joi/lib/types/any/index.js:529:50)\n       at module.exports.internals.Any._validate (/usr/share/kibana/node_modules/joi/lib/types/any/index.js:656:28)\n       at internals.Alternatives._base (/usr/share/kibana/node_modules/joi/lib/types/alternatives/index.js:50:38)\n       at internals.Alternatives._validate (/usr/share/kibana/node_modules/joi/lib/types/any/index.js:614:37)\n       at type._base (/usr/share/kibana/node_modules/joi/lib/types/object/index.js:212:45)\n       at type._validate (/usr/share/kibana/node_modules/joi/lib/types/any/index.js:614:37)\n       at type._validateWithOptions (/usr/share/kibana/node_modules/joi/lib/types/any/index.js:674:29)\n       at module.exports.internals.Any.root.validate (/usr/share/kibana/node_modules/joi/lib/index.js:146:23)\n       at ObjectType.validate (/usr/share/kibana/node_modules/@kbn/config-schema/target/out/types/type.js:56:72)\n       at ConfigService.validateAtPath (/usr/share/kibana/src/core/server/config/config_service.js:188:19)\n       at MapSubscriber.getDistinctConfig.pipe.config [as project] (/usr/share/kibana/src/core/server/config/config_service.js:196:81)\n       at MapSubscriber._next (/usr/share/kibana/node_modules/rxjs/internal/operators/map.js:49:35)\n       at MapSubscriber.Subscriber.next (/usr/share/kibana/node_modules/rxjs/internal/Subscriber.js:66:18)\n       at DistinctUntilChangedSubscriber._next (/usr/share/kibana/node_modules/rxjs/internal/operators/distinctUntilChanged.js:69:30) cause: undefined, path: [ 'encryptionKey' ] } }"}
Jul 25 21:23:09 test-host kibana[18650]:  FATAL  Error: [config validation of [xpack.reporting].encryptionKey]: value has length [20] but it must have a minimum length of [32].
Jul 25 21:23:10 test-host systemd[1]: kibana.service: Main process exited, code=exited, status=1/FAILURE
Jul 25 21:23:10 test-host systemd[1]: kibana.service: Unit entered failed state.
Jul 25 21:23:10 test-host systemd[1]: kibana.service: Failed with result 'exit-code'.

Any additional context:

According to documentation at https://www.elastic.co/guide/en/kibana/7.8/reporting-settings-kb.html must be an "any text string", with no mention of required length. So either validation or documentation is wrong. This is an incompatible breaking change of a setting that forked fine in 7.4.

[hendry-lim]

This was fixed in #69827.

[piotrp]

Thanks for pointing that out, I didn't find it when I checked.