lab: Add show mr approval rules

The WebUI provides a mechanism to view the status of MR approval rules on a
specific MR.  Add this functionality to lab.

Usage: 'lab mr approval-rule 1234'

One thing to note is that, unlike the WebUI, lab currently does not show
the 'Commented By' data.  This is because getting the data is expensive,
and at this time provides little functionality.  This can be added if
users request it.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>

Author: prarit

cmd/mr_approval_rules.go

@@ -0,0 +1,80 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/MakeNowJust/heredoc/v2"
+	"github.com/spf13/cobra"
+	lab "github.com/zaquestion/lab/internal/gitlab"
+
+	gitlab "github.com/xanzy/go-gitlab"
+)
+
+func mrApprovalRuleShow(approvalState *gitlab.MergeRequestApprovalState) {
+	for _, rule := range approvalState.Rules {
+		fmt.Println("Rule:", rule.Name)
+		if rule.Approved {
+			fmt.Println("   Approved: Y")
+		} else {
+			fmt.Println("   Approved:")
+		}
+
+		if rule.RuleType == "regular" {
+			users := ""
+			for u, user := range rule.EligibleApprovers {
+				users += fmt.Sprintf("%s", user.Username)
+				if u != (len(rule.EligibleApprovers) - 1) {
+					users +=","
+				}
+			}
+			fmt.Println("   Approvers:", users)
+		} else if rule.RuleType == "any_approver" {
+			fmt.Println("   Approvers: All eligible users")
+		}
+
+		if rule.ApprovalsRequired > 0 {
+			fmt.Printf("   Approvals: %d of %d\n", len(rule.ApprovedBy), rule.ApprovalsRequired)
+		} else {
+			fmt.Println("   Approvals: Optional")
+		}
+
+		if len(rule.ApprovedBy) > 0 {
+			users := ""
+			for u, user := range rule.ApprovedBy {
+				users += fmt.Sprintf("%s", user.Username)
+				if u != (len(rule.ApprovedBy) - 1) {
+					users +=","
+				}
+			}
+			fmt.Println("   Approved By:", users)
+		} else {
+			fmt.Println("   Approved By:")
+		}
+	}
+}
+
+var mrApprovalRuleCmd = &cobra.Command{
+	Use:     "approval-rule [remote] [<MR id or branch>]",
+	Aliases: []string{},
+	Example: heredoc.Doc(`
+		lab mr approval-rule 1234`),
+	PersistentPreRun: labPersistentPreRun,
+	Run: func(cmd *cobra.Command, args []string) {
+		rn, id, err := parseArgsWithGitBranchMR(args)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		approvalState, err := lab.GetMRApprovalState(rn, int(id))
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		// default, no options just show the rules
+		mrApprovalRuleShow(approvalState)
+	},
+}
+
+func init() {
+	mrCmd.AddCommand(mrApprovalRuleCmd)
+}

internal/gitlab/gitlab.go

@@ -1600,6 +1600,16 @@ func GetMRApprovalsConfiguration(projID interface{}, id int) (*gitlab.MergeReque
 	return configuration, err
 }
 
+// GetMRApprovalsState returns the current MR approval rule
+func GetMRApprovalState(projID interface{}, id int) (*gitlab.MergeRequestApprovalState, error) {
+	state, _, err := lab.MergeRequestApprovals.GetApprovalState(projID, id)
+	if err != nil {
+		return nil, err
+	}
+
+	return state, err
+}
+
 // ResolveMRDiscussion resolves a discussion (blocking thread) based on its ID
 func ResolveMRDiscussion(projID interface{}, mrID int, discussionID string, noteID int) (string, error) {
 	opts := &gitlab.ResolveMergeRequestDiscussionOptions{