Adds three functions:
`withStoredImages` iterates over a list of models.Alerts, extracting a stored image's data from storage, if available, and executing a user-provided function.
`withStoredImage` does this for an image attached to a specific alert.
`openImage` finds and opens an image file on disk.
Moves `store.Image` to `models.Image`
Simplifies `channels.ImageStore` interface and updates notifiers that use it to use the simpler methods.
Updates all pkg/alert/notifier/channels to use withStoredImage routines.
This change extracts screenshot data from alert messages via a private annotation `__alertScreenshotToken__` and attaches a URL to a Slack message or uploads the data to an image upload endpoint if needed.
This change also implements a few foundational functions for use in other notifiers.
The State Manager will now take screenshots when an alert instance
switches to an Alerting or Resolved state.
Signed-off-by: Joe Blubaugh joe.blubaugh@grafana.com
This commit adds a pkg/services/screenshot package for taking and uploading screenshots of Grafana dashboards. It supports taking screenshots of both dashboards and individual panels within a dashboard, using the rendering service.
The screenshot package has the following services, most of which can be composed:
BrowserScreenshotService (Takes screenshots with headless Chrome)
CachableScreenshotService (Caches screenshots taken with another service such as BrowserScreenshotService)
NoopScreenshotService (A no-op screenshot service for tests)
SingleFlightScreenshotService (Prevents duplicate screenshots when taking screenshots of the same dashboard or panel in parallel)
ScreenshotUnavailableService (A screenshot service that returns ErrScreenshotsUnavailable)
UploadingScreenshotService (A screenshot service that uploads taken screenshots)
The screenshot package does not support wire dependency injection yet. ngalert constructs its own version of the service. See https://github.com/grafana/grafana/issues/49296
This PR also adds an ImageScreenshotService to ngAlert. This is used to take screenshots with a screenshotservice and then store their location reference for use by alert instances and notifiers.
