47 lines
1.3 KiB
Go
47 lines
1.3 KiB
Go
package supervisor
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// Supporting infrastructure to allow running some non-Go payloads under supervision.
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import (
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"context"
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"net"
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"os/exec"
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"google.golang.org/grpc"
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)
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// GRPCServer creates a Runnable that serves gRPC requests as longs as it's not canceled.
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// If graceful is set to true, the server will be gracefully stopped instead of plain stopped. This means all pending
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// RPCs will finish, but also requires streaming gRPC handlers to check their context liveliness and exit accordingly.
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// If the server code does not support this, `graceful` should be false and the server will be killed violently instead.
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func GRPCServer(srv *grpc.Server, lis net.Listener, graceful bool) Runnable {
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return func(ctx context.Context) error {
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Signal(ctx, SignalHealthy)
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errC := make(chan error)
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go func() {
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errC <- srv.Serve(lis)
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}()
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select {
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case <-ctx.Done():
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if graceful {
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srv.GracefulStop()
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} else {
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srv.Stop()
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}
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return ctx.Err()
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case err := <-errC:
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return err
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}
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}
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}
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// Command will create a Runnable that starts a long-running command, whose exit is determined to be a failure.
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func Command(name string, arg ...string) Runnable {
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return func(ctx context.Context) error {
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Signal(ctx, SignalHealthy)
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cmd := exec.CommandContext(ctx, name, arg...)
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return cmd.Run()
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}
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}
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