_examples: context

1 files changed, 46 insertions, 0 deletions

diff --git a/_examples/context/main.go b/_examples/context/main.go
new file mode 100644
index 0000000..72885ff
--- /dev/null
+++ b/_examples/context/main.go
@@ -0,0 +1,46 @@
+package main
+
+import (
+	"context"
+	"os"
+	"os/signal"
+
+	"gopkg.in/src-d/go-git.v4"
+	. "gopkg.in/src-d/go-git.v4/_examples"
+)
+
+// Gracefull cancellation example of a basic git operation such as Clone.
+func main() {
+	CheckArgs("<url>", "<directory>")
+	url := os.Args[1]
+	directory := os.Args[2]
+
+	// Clone the given repository to the given directory
+	Info("git clone %s %s", url, directory)
+
+	stop := make(chan os.Signal, 1)
+	signal.Notify(stop, os.Interrupt)
+
+	// The context is the mechanism used by go-git, to support deadlines and
+	// cancellation signals.
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel() // cancel when we are finished consuming integers
+
+	go func() {
+		<-stop
+		Warning("\nSignal detected, canceling operation...")
+		cancel()
+	}()
+
+	Warning("To gracefully stop the clone operation, push Crtl-C.")
+
+	// Using PlainCloneContext we can provide to a context, if the context
+	// is cancelled, the clone operation stops gracefully.
+	_, err := git.PlainCloneContext(ctx, directory, false, &git.CloneOptions{
+		URL:      url,
+		Progress: os.Stdout,
+	})
+
+	// If the context was cancelled, an error is returned.
+	CheckIfError(err)
+}