internal/rest/client: Add the client GetExtensions client function

Signed-off-by: Gabriel Mougard <[email protected]>

internal/rest/client/extensions.go

@@ -0,0 +1,29 @@
+package client
+
+import (
+	"context"
+	"time"
+
+	"github.com/canonical/lxd/shared/api"
+	"github.com/canonical/microcluster/internal/rest/types"
+)
+
+// GetExtensions returns the runtime extensions of the MicroCluster deployment.
+func (c *Client) GetExtensions(ctx context.Context, extensionVendor string, extensionName string) ([]types.RuntimeExtension, error) {
+	queryCtx, cancel := context.WithTimeout(ctx, 30*time.Second)
+	defer cancel()
+
+	endpoint := api.NewURL().Path("extensions")
+	if extensionVendor != "" {
+		endpoint = endpoint.WithQuery("vendor", extensionVendor)
+	}
+
+	if extensionName != "" {
+		endpoint = endpoint.WithQuery("extension", extensionName)
+	}
+
+	extensions := []types.RuntimeExtension{}
+	err := c.QueryStruct(queryCtx, "GET", PublicEndpoint, endpoint, nil, &extensions)
+
+	return extensions, err
+}