If the scope-app API unexpectedly restarts, it has no report
at hand (until it gets one from the probe) and sends node
count 0 to the frontend for all topologies. Once the report
arrives, it will send the proper count.
What happened was the frontend did hide Processes for a short
time till the node count recovered. This moved the topology
selection to the always visible Containers (hide_if_empty == false)
while keeping the graph as is.
Once the node count recovers, Processes comes back but the
selection is still at Containers.
We now keep the selected topology visible at all time even if
the API returns a node count of 0. This recovers nicely when
the correct node counts come in. Once the user selects a different
topology while and a backend response arrives, it disappears.
Fixes#2646
* Node details fetching reports at proper timestamp.
* Corrected all the relevant timestamps in the UI.
* Renamed some state variables.
* Time travel works for topologies list.
* Added a whole screen overlay for time travel.
* Polished the backend.
* Make time travel work also with the Resource View.
* Fixed the jest tests.
* Fixed the empty view message for resource view.
* Some naming polishing.
* Addressed the comments.
* Hacky working prototype.
* Operate with time.Duration offset instead of fixed timestamp.
* Polished the backend code.
* Made a nicer UI component.
* Small refactorings of the websockets code.
* Fixed the backend tests.
* Better websocketing and smoother transitions
* Small styling refactoring.
* Detecting empty topologies.
* Improved error messaging.
* Addressed some of David's comments.
* Moved nodesDeltaBuffer to a global state to fix the paused status rendering bug.
* Small styling changes
* Changed the websocket global state variables a bit.
* Polishing & refactoring.
* More polishing.
* Final refactoring.
* Addressed a couple of bugs.
* Hidden the timeline control behind Cloud context and a feature flag.
* Addressed most of @davkal's comments.
* Added mixpanel tracking.
* Added resource view selector button
* Showing resource boxes in the resource view
* Crude CPU resource view prototype
* Improved the viewMode state logic
* Extracted zooming into a separate wrapper component
* Split the layout selectors between graph-view and resource-view
* Proper zooming logic for the resource view
* Moved all node networks utils to selectors
* Improved the zoom caching logic
* Further refactoring of selectors
* Added sticky labels to the resource boxes
* Added panning translation limits in the resource view
* Renamed GridModeSelector -> ViewModeSelector
* Polished the topology resource view selection logic
* Search bar hidden in the resource view
* Added per-layer topology names to the resource view
* Made metric selectors work for the resource view
* Adjusted the viewport selectors
* Renamed viewport selector to canvas (+ maximal zoom fix)
* Showing more useful metric info in the resource box labels
* Fetching only necessary nodes for the resource view
* Refactored the resource view layer component
* Addressed first batch UI comments (from the Scope meeting)
* Switch to deep zooming transform in the resource view to avoid SVG precision errors
* Renamed and moved resource view components
* Polished all the resource view components
* Changing the available metrics selection
* Improved and polished the state transition logic for the resource view
* Separated zoom limits from the zoom active state
* Renaming and bunch of comments
* Addressed all the UI comments (@davkal + @fons)
* Made graph view selectors independent from resource view selectors
