A z-index value of less than 1020 is needed because the time selection
dropdown shares the latter value via inheritance. Arbitrarily picked
1015 because it is a notch down.
Related: #14004
- Logging gets a graph for log distribution (currently per stream, but I
think I'll change that to per log-level)
- added grid columns for timestamp and unique labels
- show common labels of streams
- View options to show/hide time columns, label columns
- created `--small` modifier for Switch CSS classes
- merging of streams is now a datasource responsibility
- changed `start()` to return promise on main language feature task
- promise resolves to list of secondary tasks
- speeds up time to interaction of metric selector
- lazy loading of certain metric selector and log label selector items
- loading indication of metric and log label selectors
this is a fix-up PR that cleans up Explore Logging after the recent
restructuring.
- log results need to be merged since query transactions have been
introduced
- logging DS has its own language provider, query field, and start page
(some of them based on prometheus components)
- added loader animation to log viewer
- removed logging logic from prometheus components
- when instantiating a datasource, the datasource service checks if the
plugin module exports Explore components, and if so, attaches them to
the datasource
- Explore component makes all major internal pluggable from a datasource
`exploreComponents` property
- Moved Prometheus query field to promehteus datasource and registered
it as an exported Explore component
- Added new Start page for Explore, also exported from the datasource
- use global range types
- add ErrorBoundary around individual Explore components
- fix table merge on empty results
- fix TimePicker date parsing on ISO dates
- fix TimePicker range string after relative move
