Previously we were depending on the GUI(s) to do it.
By doing it in tailscaled, GUIs can be simplified and be
guaranteed to render consistent results.
If warnable A depends on warnable B, if both A & B are unhealhy, only
B will be shown to the GUI as unhealthy. Once B clears up, only then
will A be presented as unhealthy.
Updates #14687
Change-Id: Id8566f2672d8d2d699740fa053d4e2a2c8009e83
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Updates tailscale/tailscale#4136
To reduce the likelihood of presenting spurious warnings, add the ability to delay the visibility of certain Warnables, based on a TimeToVisible time.Duration field on each Warnable. The default is zero, meaning that a Warnable is immediately visible to the user when it enters an unhealthy state.
Signed-off-by: Andrea Gottardo <andrea@gottardo.me>
Updates tailscale/tailscale#4136
We should make sure to send the value of ImpactsConnectivity over to the clients using LocalAPI as they need it to display alerts in the GUI properly.
Signed-off-by: Andrea Gottardo <andrea@gottardo.me>
Updates #4136
Small PR to expose the health Warnables dependencies to the GUI via LocalAPI, so that we can only show warnings for root cause issues, and filter out unnecessary messages before user presentation.
Signed-off-by: Andrea Gottardo <andrea@gottardo.me>
Updates tailscale/tailscale#4136
This PR is the first round of work to move from encoding health warnings as strings and use structured data instead. The current health package revolves around the idea of Subsystems. Each subsystem can have (or not have) a Go error associated with it. The overall health of the backend is given by the concatenation of all these errors.
This PR polishes the concept of Warnable introduced by @bradfitz a few weeks ago. Each Warnable is a component of the backend (for instance, things like 'dns' or 'magicsock' are Warnables). Each Warnable has a unique identifying code. A Warnable is an entity we can warn the user about, by setting (or unsetting) a WarningState for it. Warnables have:
- an identifying Code, so that the GUI can track them as their WarningStates come and go
- a Title, which the GUIs can use to tell the user what component of the backend is broken
- a Text, which is a function that is called with a set of Args to generate a more detailed error message to explain the unhappy state
Additionally, this PR also begins to send Warnables and their WarningStates through LocalAPI to the clients, using ipn.Notify messages. An ipn.Notify is only issued when a warning is added or removed from the Tracker.
In a next PR, we'll get rid of subsystems entirely, and we'll start using structured warnings for all errors affecting the backend functionality.
Signed-off-by: Andrea Gottardo <andrea@gottardo.me>
