improve error msg, check content of response

src/k8s/cmd/k8s/k8s_bootstrap.go

@@ -60,8 +60,8 @@ func newBootstrapCmd(env cmdutil.ExecutionEnvironment) *cobra.Command {
 				env.Exit(1)
 				return
 			}
-			if microk8sInfo.StatusCode == 200 {
-				cmd.PrintErrln("Error: microk8s snap is installed, please remove it and try again.")
+			if microk8sInfo.StatusCode == 200 && !microk8sInfo.Result.InstallDate.IsZero() {
+				cmd.PrintErrln("Error: microk8s snap is installed. Please remove it using the following command and try again:\n\n  sudo snap remove microk8s")
 				env.Exit(1)
 				return
 			}

src/k8s/pkg/client/snapd/snap_info.go

@@ -4,13 +4,19 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"time"
 )
 
-type snapdSnapInfoResponse struct {
-	StatusCode int `json:"status-code"`
+type SnapInfoResult struct {
+	InstallDate time.Time `json:"install-date"`
 }
 
-func (c *Client) GetSnapInfo(snap string) (*snapdSnapInfoResponse, error) {
+type SnapInfoResponse struct {
+	StatusCode int            `json:"status-code"`
+	Result     SnapInfoResult `json:"result"`
+}
+
+func (c *Client) GetSnapInfo(snap string) (*SnapInfoResponse, error) {
 	resp, err := c.client.Get(fmt.Sprintf("http://localhost/v2/snaps/%s", snap))
 	if err != nil {
 		return nil, fmt.Errorf("failed to get snapd snap info: %w", err)
@@ -22,7 +28,7 @@ func (c *Client) GetSnapInfo(snap string) (*snapdSnapInfoResponse, error) {
 		return nil, fmt.Errorf("client: could not read response body: %w", err)
 	}
 
-	var snapInfoResponse snapdSnapInfoResponse
+	var snapInfoResponse SnapInfoResponse
 	if err := json.Unmarshal(resBody, &snapInfoResponse); err != nil {
 		return nil, fmt.Errorf("client: could not unmarshal response body: %w", err)
 	}