62 lines
1.5 KiB
Go
62 lines
1.5 KiB
Go
package metrics
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// Healthchecks hold an error value describing an arbitrary up/down status.
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type Healthcheck interface {
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Check()
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Error() error
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Healthy()
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Unhealthy(error)
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}
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// NewHealthcheck constructs a new Healthcheck which will use the given
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// function to update its status.
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func NewHealthcheck(f func(Healthcheck)) Healthcheck {
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if UseNilMetrics {
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return NilHealthcheck{}
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}
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return &StandardHealthcheck{nil, f}
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}
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// NilHealthcheck is a no-op.
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type NilHealthcheck struct{}
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// Check is a no-op.
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func (NilHealthcheck) Check() {}
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// Error is a no-op.
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func (NilHealthcheck) Error() error { return nil }
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// Healthy is a no-op.
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func (NilHealthcheck) Healthy() {}
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// Unhealthy is a no-op.
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func (NilHealthcheck) Unhealthy(error) {}
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// StandardHealthcheck is the standard implementation of a Healthcheck and
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// stores the status and a function to call to update the status.
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type StandardHealthcheck struct {
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err error
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f func(Healthcheck)
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}
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// Check runs the healthcheck function to update the healthcheck's status.
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func (h *StandardHealthcheck) Check() {
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h.f(h)
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}
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// Error returns the healthcheck's status, which will be nil if it is healthy.
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func (h *StandardHealthcheck) Error() error {
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return h.err
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}
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// Healthy marks the healthcheck as healthy.
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func (h *StandardHealthcheck) Healthy() {
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h.err = nil
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}
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// Unhealthy marks the healthcheck as unhealthy. The error is stored and
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// may be retrieved by the Error method.
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func (h *StandardHealthcheck) Unhealthy(err error) {
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h.err = err
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}
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