Add ability to specify a team as an approver (trstringer#32)

Prior to this change, the approvers could only be explicit users. With
this change, you can now specify an org team and this will be expanded
out with a user list for approvers.

Closes trstringer#14.

Author: trstringer

Diff for: .gitignore

@@ -0,0 +1 @@
+.env

Diff for: README.md

@@ -29,12 +29,12 @@ steps:
   - uses: trstringer/manual-approval@v1
     with:
       secret: ${{ github.TOKEN }}
-      approvers: user1,user2
+      approvers: user1,user2,org-team1
       minimum-approvals: 1
       issue-title: "Deploying v1.3.5 to prod from staging"
 ```
 
-- `approvers` is a comma-delimited list of all required approvers. (*Note: Required approvers must have the ability to be set as approvers in the repository. If you add an approver that doesn't have this permission then you would receive an HTTP/402 Validation Failed error when running this action*)
+- `approvers` is a comma-delimited list of all required approvers. An approver can either be a user or an org team. (*Note: Required approvers must have the ability to be set as approvers in the repository. If you add an approver that doesn't have this permission then you would receive an HTTP/402 Validation Failed error when running this action*)
 - `minimum-approvals` is an integer that sets the minimum number of approvals required to progress the workflow. Defaults to ALL approvers.
 - `issue-title` is a string that will be appened to the title of the issue.
 

Diff for: approval.go

@@ -15,11 +15,11 @@ type approvalEnvironment struct {
 	repo                string
 	repoOwner           string
 	runID               int
-	approvers           []string
-	minimumApprovals    int
 	approvalIssue       *github.Issue
 	approvalIssueNumber int
 	issueTitle          string
+	issueApprovers      []string
+	minimumApprovals    int
 }
 
 func newApprovalEnvironment(client *github.Client, repoFullName, repoOwner string, runID int, approvers []string, minimumApprovals int, issueTitle string) (*approvalEnvironment, error) {
@@ -35,7 +35,7 @@ func newApprovalEnvironment(client *github.Client, repoFullName, repoOwner strin
 		repo:             repo,
 		repoOwner:        repoOwner,
 		runID:            runID,
-		approvers:        approvers,
+		issueApprovers:   approvers,
 		minimumApprovals: minimumApprovals,
 		issueTitle:       issueTitle,
 	}, nil
@@ -59,7 +59,7 @@ Required approvers: %s
 
 Respond %s to continue workflow or %s to cancel.`,
 		a.runURL(),
-		a.approvers,
+		a.issueApprovers,
 		formatAcceptedWords(approvedWords),
 		formatAcceptedWords(deniedWords),
 	)
@@ -69,13 +69,13 @@ Respond %s to continue workflow or %s to cancel.`,
 		a.repoOwner,
 		a.repo,
 		issueTitle,
-		a.approvers,
+		a.issueApprovers,
 		issueBody,
 	)
 	a.approvalIssue, _, err = a.client.Issues.Create(ctx, a.repoOwner, a.repo, &github.IssueRequest{
 		Title:     &issueTitle,
 		Body:      &issueBody,
-		Assignees: &a.approvers,
+		Assignees: &a.issueApprovers,
 	})
 	a.approvalIssueNumber = a.approvalIssue.GetNumber()
 	return err

Diff for: approvers.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/google/go-github/v43/github"
+)
+
+func retrieveApprovers(client *github.Client, repoOwner string) ([]string, error) {
+	approvers := []string{}
+
+	requiredApproversRaw := os.Getenv(envVarApprovers)
+	requiredApprovers := strings.Split(requiredApproversRaw, ",")
+
+	for _, approverUser := range requiredApprovers {
+		expandedUsers := expandGroupFromUser(client, repoOwner, approverUser)
+		if expandedUsers != nil {
+			approvers = append(approvers, expandedUsers...)
+		} else {
+			approvers = append(approvers, approverUser)
+		}
+	}
+
+	approvers = deduplicateUsers(approvers)
+
+	minimumApprovalsRaw := os.Getenv(envVarMinimumApprovals)
+	minimumApprovals := len(approvers)
+	var err error
+	if minimumApprovalsRaw != "" {
+		minimumApprovals, err = strconv.Atoi(minimumApprovalsRaw)
+		if err != nil {
+			return nil, fmt.Errorf("error parsing minimum number of approvals: %w", err)
+		}
+	}
+
+	if minimumApprovals > len(approvers) {
+		return nil, fmt.Errorf("error: minimum required approvals (%d) is greater than the total number of approvers (%d)", minimumApprovals, len(approvers))
+	}
+
+	return approvers, nil
+}
+
+func expandGroupFromUser(client *github.Client, org, userOrTeam string) []string {
+	users, _, err := client.Teams.ListTeamMembersBySlug(context.Background(), org, userOrTeam, &github.TeamListTeamMembersOptions{})
+	if err != nil || len(users) == 0 {
+		return nil
+	}
+
+	userNames := make([]string, 0, len(users))
+	for _, user := range users {
+		userNames = append(userNames, user.GetLogin())
+	}
+
+	return userNames
+}
+
+func deduplicateUsers(users []string) []string {
+	uniqValuesByKey := make(map[string]bool)
+	uniqUsers := []string{}
+	for _, user := range users {
+		if _, ok := uniqValuesByKey[user]; !ok {
+			uniqValuesByKey[user] = true
+			uniqUsers = append(uniqUsers, user)
+		}
+	}
+	return uniqUsers
+}

Diff for: approvers_test.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestDeduplicateUsers(t *testing.T) {
+	testCases := []struct {
+		name     string
+		input    []string
+		expected []string
+	}{
+		{
+			name:     "with_duplicate_user",
+			input:    []string{"first", "second", "first"},
+			expected: []string{"first", "second"},
+		},
+		{
+			name:     "without_duplicate_user",
+			input:    []string{"first", "second"},
+			expected: []string{"first", "second"},
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			actual := deduplicateUsers(testCase.input)
+			if !reflect.DeepEqual(testCase.expected, actual) {
+				t.Fatalf(
+					"unequal depulicated: expected %v actual %v",
+					testCase.expected,
+					actual,
+				)
+			}
+		})
+	}
+}

Diff for: main.go

@@ -6,7 +6,6 @@ import (
 	"os"
 	"os/signal"
 	"strconv"
-	"strings"
 	"time"
 
 	"github.com/google/go-github/v43/github"
@@ -31,7 +30,7 @@ func handleInterrupt(ctx context.Context, client *github.Client, apprv *approval
 	}
 }
 
-func newCommentLoopChannel(ctx context.Context, apprv *approvalEnvironment, client *github.Client, approvers []string, minimumApprovals int) chan int {
+func newCommentLoopChannel(ctx context.Context, apprv *approvalEnvironment, client *github.Client) chan int {
 	channel := make(chan int)
 	go func() {
 		for {
@@ -42,7 +41,7 @@ func newCommentLoopChannel(ctx context.Context, apprv *approvalEnvironment, clie
 				close(channel)
 			}
 
-			approved, err := approvalFromComments(comments, approvers, minimumApprovals)
+			approved, err := approvalFromComments(comments, apprv.issueApprovers, apprv.minimumApprovals)
 			if err != nil {
 				fmt.Printf("error getting approval from comments: %v\n", err)
 				channel <- 1
@@ -106,7 +105,40 @@ func newGithubClient(ctx context.Context) *github.Client {
 	return github.NewClient(tc)
 }
 
+func validateInput() error {
+	missingEnvVars := []string{}
+	if os.Getenv(envVarRepoFullName) == "" {
+		missingEnvVars = append(missingEnvVars, envVarRepoFullName)
+	}
+
+	if os.Getenv(envVarRunID) == "" {
+		missingEnvVars = append(missingEnvVars, envVarRunID)
+	}
+
+	if os.Getenv(envVarRepoOwner) == "" {
+		missingEnvVars = append(missingEnvVars, envVarRepoOwner)
+	}
+
+	if os.Getenv(envVarToken) == "" {
+		missingEnvVars = append(missingEnvVars, envVarToken)
+	}
+
+	if os.Getenv(envVarApprovers) == "" {
+		missingEnvVars = append(missingEnvVars, envVarApprovers)
+	}
+
+	if len(missingEnvVars) > 0 {
+		return fmt.Errorf("missing env vars: %v", missingEnvVars)
+	}
+	return nil
+}
+
 func main() {
+	if err := validateInput(); err != nil {
+		fmt.Printf("%v\n", err)
+		os.Exit(1)
+	}
+
 	repoFullName := os.Getenv(envVarRepoFullName)
 	runID, err := strconv.Atoi(os.Getenv(envVarRunID))
 	if err != nil {
@@ -118,26 +150,22 @@ func main() {
 	ctx := context.Background()
 	client := newGithubClient(ctx)
 
-	requiredApproversRaw := os.Getenv(envVarApprovers)
-	fmt.Printf("Required approvers: %s\n", requiredApproversRaw)
-	approvers := strings.Split(requiredApproversRaw, ",")
+	approvers, err := retrieveApprovers(client, repoOwner)
+	if err != nil {
+		fmt.Printf("error retrieving approvers: %v\n", err)
+		os.Exit(1)
+	}
 
+	issueTitle := os.Getenv(envVarIssueTitle)
 	minimumApprovalsRaw := os.Getenv(envVarMinimumApprovals)
-	minimumApprovals := len(approvers)
+	minimumApprovals := 0
 	if minimumApprovalsRaw != "" {
 		minimumApprovals, err = strconv.Atoi(minimumApprovalsRaw)
 		if err != nil {
-			fmt.Printf("error parsing minimum number of approvals: %v\n", err)
+			fmt.Printf("error parsing minimum approvals: %v\n", err)
 			os.Exit(1)
 		}
 	}
-
-	if minimumApprovals > len(approvers) {
-		fmt.Printf("error: minimum required approvals (%v) is greater than the total number of approvers (%v)\n", minimumApprovals, len(approvers))
-		os.Exit(1)
-	}
-
-	issueTitle := os.Getenv(envVarIssueTitle)
 	apprv, err := newApprovalEnvironment(client, repoFullName, repoOwner, runID, approvers, minimumApprovals, issueTitle)
 	if err != nil {
 		fmt.Printf("error creating approval environment: %v\n", err)
@@ -153,7 +181,7 @@ func main() {
 	killSignalChannel := make(chan os.Signal, 1)
 	signal.Notify(killSignalChannel, os.Interrupt)
 
-	commentLoopChannel := newCommentLoopChannel(ctx, apprv, client, approvers, minimumApprovals)
+	commentLoopChannel := newCommentLoopChannel(ctx, apprv, client)
 
 	select {
 	case exitCode := <-commentLoopChannel: