# Error checking of configuration files at startup? **URL:** \ **Category:** Elasticsearch\ **Created:** [May 17, 2011, 12:38pm UTC](https://discuss.elastic.co/t/error-checking-of-configuration-files-at-startup/4422 "2011-05-17T12:38:52Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Michael\_McCandless](https://avatars.discourse-cdn.com/v4/letter/m/e47c2d/32.png) [@Michael\_McCandless](https://discuss.elastic.co/u/Michael_McCandless)\ **Post date:** [May 17, 2011, 12:38pm UTC](https://discuss.elastic.co/t/error-checking-of-configuration-files-at-startup/4422/1 "2011-05-17T12:38:52Z")
Hi, Since we've been discussing on the Solr list how to handle configuration errors at startup (see [http://markmail.org/thread/ywkfmxjboyixkrjc](http://markmail.org/thread/ywkfmxjboyixkrjc)), I was also curious how ElasticSearch handles this. So I installed 0.16, and intentionally put two typos in my config/elasticsearch.yml: # Cluster Settings cluster: nameX: elasticsearch foobar The foobar indeed causes an error message and elasticsearch refuses to start (a good thing, I think): - SettingsException[Failed to load settings from [file:/home/mike/src/elasticsearch-0.16.0/config/elasticsearch.yml]] ScannerException[while scanning a simple key; could not found expected ':'] Though, that message doesn't tell me the line number... However, if I remove the foobar and leave the "nameX: ..." line, there's no erorr nor warning. Is that expected? I think it would be better if mis-spellings were treated as a hard error (server doesn't start) so users don't incorrectly think they've configured something? Mike [http://blog.mikemccandless.com](http://blog.mikemccandless.com) ---
**Author:** ![kimchy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/kimchy/32/44952_2.png) [@kimchy](https://discuss.elastic.co/u/kimchy)\ **Post date:** [May 17, 2011, 6:04pm UTC](https://discuss.elastic.co/t/error-checking-of-configuration-files-at-startup/4422/2 "2011-05-17T18:04:46Z")
Agreed, it would be great to handle such mis configuration (i.e. nameX and not name), though it gets tricky when it comes to building a modular system with custom possible plugins (i.e. what part of the system each module is "responsible" to validate, and what are the valid setting names are). Its not done in elasticsearch, but, corresponding to each module config, one can set it to DEBUG level in the logging, and see exactly the configuration values set for it (and check if the settings took place). Not optimal, but thats what we have today. On Tuesday, May 17, 2011 at 3:38 PM, Michael McCandless wrote: > Hi, > > Since we've been discussing on the Solr list how to handle > configuration errors at startup (see > [http://markmail.org/thread/ywkfmxjboyixkrjc](http://markmail.org/thread/ywkfmxjboyixkrjc)), I was also curious how > Elasticsearch handles this. > > So I installed 0.16, and intentionally put two typos in my > config/elasticsearch.yml: > > # Cluster Settings > > cluster: > nameX: elasticsearch > foobar > > The foobar indeed causes an error message and elasticsearch refuses to > start (a good thing, I think): > > - SettingsException[Failed to load settings from > [file:/home/mike/src/elasticsearch-0.16.0/config/elasticsearch.yml]] > ScannerException[while scanning a simple key; could not found expected ':'] > > Though, that message doesn't tell me the line number... > > However, if I remove the foobar and leave the "nameX: ..." line, > there's no erorr nor warning. Is that expected? I think it would be > better if mis-spellings were treated as a hard error (server doesn't > start) so users don't incorrectly think they've configured something? > > Mike > > [http://blog.mikemccandless.com](http://blog.mikemccandless.com) ---
**Author:** ![Michael\_McCandless](https://avatars.discourse-cdn.com/v4/letter/m/e47c2d/32.png) [@Michael\_McCandless](https://discuss.elastic.co/u/Michael_McCandless)\ **Post date:** [May 17, 2011, 7:30pm UTC](https://discuss.elastic.co/t/error-checking-of-configuration-files-at-startup/4422/3 "2011-05-17T19:30:32Z")
Thanks Shay. We have the same challenge in Solr, where because plugins can "claim" arbitrary configuration, misconfiguration can easily remain undetected... I think somehow a plugin should explicitly "claim" which settings it has validated. Then at the end of initializing all plugins, if any configured settings were not claimed by any plugins, that's a hard error. This would require more work on plugin-writers' part, but it means users of those plugins get a tighter experience, knowing if they've misconfigured something. Mike [http://blog.mikemccandless.com](http://blog.mikemccandless.com) On Tue, May 17, 2011 at 2:04 PM, Shay Banon [shay.banon@elasticsearch.com](mailto:shay.banon@elasticsearch.com) wrote: > Agreed, it would be great to handle such mis configuration (i.e. nameX and > not name), though it gets tricky when it comes to building a modular system > with custom possible plugins (i.e. what part of the system each module is > "responsible" to validate, and what are the valid setting names are). > Its not done in elasticsearch, but, corresponding to each module config, one > can set it to DEBUG level in the logging, and see exactly the configuration > values set for it (and check if the settings took place). Not optimal, but > thats what we have today. > > On Tuesday, May 17, 2011 at 3:38 PM, Michael McCandless wrote: > > Hi, > > Since we've been discussing on the Solr list how to handle > configuration errors at startup (see > [http://markmail.org/thread/ywkfmxjboyixkrjc](http://markmail.org/thread/ywkfmxjboyixkrjc)), I was also curious how > Elasticsearch handles this. > > So I installed 0.16, and intentionally put two typos in my > config/elasticsearch.yml: > > # Cluster Settings > > cluster: > nameX: elasticsearch > foobar > > The foobar indeed causes an error message and elasticsearch refuses to > start (a good thing, I think): > > - SettingsException[Failed to load settings from > [file:/home/mike/src/elasticsearch-0.16.0/config/elasticsearch.yml]] > ScannerException[while scanning a simple key; could not found expected ':'] > > Though, that message doesn't tell me the line number... > > However, if I remove the foobar and leave the "nameX: ..." line, > there's no erorr nor warning. Is that expected? I think it would be > better if mis-spellings were treated as a hard error (server doesn't > start) so users don't incorrectly think they've configured something? > > Mike > > [http://blog.mikemccandless.com](http://blog.mikemccandless.com) ---
**Author:** ![kimchy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/kimchy/32/44952_2.png) [@kimchy](https://discuss.elastic.co/u/kimchy)\ **Post date:** [May 17, 2011, 8:38pm UTC](https://discuss.elastic.co/t/error-checking-of-configuration-files-at-startup/4422/4 "2011-05-17T20:38:14Z")
Yea, thats the logic I was thinking about as well. On Tuesday, May 17, 2011 at 10:30 PM, Michael McCandless wrote: > Thanks Shay. > > We have the same challenge in Solr, where because plugins can "claim" > arbitrary configuration, misconfiguration can easily remain > undetected... > > I think somehow a plugin should explicitly "claim" which settings it > has validated. Then at the end of initializing all plugins, if any > configured settings were not claimed by any plugins, that's a hard > error. This would require more work on plugin-writers' part, but it > means users of those plugins get a tighter experience, knowing if > they've misconfigured something. > > Mike > > [http://blog.mikemccandless.com](http://blog.mikemccandless.com) > > On Tue, May 17, 2011 at 2:04 PM, Shay Banon > [shay.banon@elasticsearch.com](mailto:shay.banon@elasticsearch.com) wrote: > > > Agreed, it would be great to handle such mis configuration (i.e. nameX and > > not name), though it gets tricky when it comes to building a modular system > > with custom possible plugins (i.e. what part of the system each module is > > "responsible" to validate, and what are the valid setting names are). > > Its not done in elasticsearch, but, corresponding to each module config, one > > can set it to DEBUG level in the logging, and see exactly the configuration > > values set for it (and check if the settings took place). Not optimal, but > > thats what we have today. > > > > On Tuesday, May 17, 2011 at 3:38 PM, Michael McCandless wrote: > > > > Hi, > > > > Since we've been discussing on the Solr list how to handle > > configuration errors at startup (see > > [http://markmail.org/thread/ywkfmxjboyixkrjc](http://markmail.org/thread/ywkfmxjboyixkrjc)), I was also curious how > > Elasticsearch handles this. > > > > So I installed 0.16, and intentionally put two typos in my > > config/elasticsearch.yml: > > > > # Cluster Settings > > > > cluster: > > nameX: elasticsearch > > foobar > > > > The foobar indeed causes an error message and elasticsearch refuses to > > start (a good thing, I think): > > > > - SettingsException[Failed to load settings from > > [file:/home/mike/src/elasticsearch-0.16.0/config/elasticsearch.yml]] > > ScannerException[while scanning a simple key; could not found expected ':'] > > > > Though, that message doesn't tell me the line number... > > > > However, if I remove the foobar and leave the "nameX: ..." line, > > there's no erorr nor warning. Is that expected? I think it would be > > better if mis-spellings were treated as a hard error (server doesn't > > start) so users don't incorrectly think they've configured something? > > > > Mike > > > > [http://blog.mikemccandless.com](http://blog.mikemccandless.com) ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 4:05am UTC](https://discuss.elastic.co/t/error-checking-of-configuration-files-at-startup/4422/5 "2017-07-06T04:05:55Z")
Closed on July 6, 2017, 4:05am UTC