Allow unsupported multi_ack capability

Azure DevOps requires capabilities multi_ack / multi_ack_detailed,
which are not fully implemented and by default are included in
transport.UnsupportedCapabilities.

The initial clone operations require a full download of the repository,
and therefore those unsupported capabilities are not as crucial, so
by removing them from that list allows for the first clone to work
successfully.

Additional fetches will yield issues, therefore to support that
repository users have to work from a clean clone until those
capabilities are fully supported. Commits and pushes back into the
repository have also been tested and work fine.

This change adds an example for cloning Azure DevOps repositories.

Signed-off-by: Paulo Gomes <pjbgf@linux.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/_examples/azure_devops/main.go b/_examples/azure_devops/main.go
new file mode 100644
index 0000000..9c02ca0
--- /dev/null
+++ b/_examples/azure_devops/main.go
@@ -0,0 +1,56 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	git "github.com/go-git/go-git/v5"
+	. "github.com/go-git/go-git/v5/_examples"
+	"github.com/go-git/go-git/v5/plumbing/protocol/packp/capability"
+	"github.com/go-git/go-git/v5/plumbing/transport"
+	"github.com/go-git/go-git/v5/plumbing/transport/http"
+)
+
+func main() {
+	CheckArgs("<url>", "<directory>", "<azuredevops_username>", "<azuredevops_password>")
+	url, directory, username, password := os.Args[1], os.Args[2], os.Args[3], os.Args[4]
+
+	// Clone the given repository to the given directory
+	Info("git clone %s %s", url, directory)
+
+	// Azure DevOps requires capabilities multi_ack / multi_ack_detailed,
+	// which are not fully implemented and by default are included in
+	// transport.UnsupportedCapabilities.
+	//
+	// The initial clone operations require a full download of the repository,
+	// and therefore those unsupported capabilities are not as crucial, so
+	// by removing them from that list allows for the first clone to work
+	// successfully.
+	//
+	// Additional fetches will yield issues, therefore work always from a clean
+	// clone until those capabilities are fully supported.
+	//
+	// New commits and pushes against a remote worked without any issues.
+	transport.UnsupportedCapabilities = []capability.Capability{
+		capability.ThinPack,
+	}
+
+	r, err := git.PlainClone(directory, false, &git.CloneOptions{
+		Auth: &http.BasicAuth{
+			Username: username,
+			Password: password,
+		},
+		URL:      url,
+		Progress: os.Stdout,
+	})
+	CheckIfError(err)
+
+	// ... retrieving the branch being pointed by HEAD
+	ref, err := r.Head()
+	CheckIfError(err)
+	// ... retrieving the commit object
+	commit, err := r.CommitObject(ref.Hash())
+	CheckIfError(err)
+
+	fmt.Println(commit)
+}