feat(issue): Add JSON output and file redirection (#841)

This change enhances the 'issue' command functionality by enabling structured JSON
output for single issue views and introducing a method for output redirection.

**Changes Implemented:**

1. Enables the existing `--output json` flag for single issue commands (e.g., 'tea issue 17'). This flag was previously ignored in this context.
2. Introduces the new `--out <filename>` flag, which redirects the marshaled JSON output from stdout to the specified file.

Feeback more then welcome.

Co-authored-by: Jonas Toth <development@jonas-toth.eu>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-on: https://gitea.com/gitea/tea/pulls/841
Reviewed-by: TheFox0x7 <thefox0x7@noreply.gitea.com>
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: Riccardo Förster <riccardo.foerster@sarad.de>
Co-committed-by: Riccardo Förster <riccardo.foerster@sarad.de>

cmd/issues.go

@@ -5,8 +5,12 @@ package cmd
 
 import (
 	stdctx "context"
+	"encoding/json"
 	"fmt"
+	"time"
 
+	"code.gitea.io/sdk/gitea"
+	"code.gitea.io/tea/cmd/flags"
 	"code.gitea.io/tea/cmd/issues"
 	"code.gitea.io/tea/modules/context"
 	"code.gitea.io/tea/modules/interact"
@@ -16,6 +20,34 @@ import (
 	"github.com/urfave/cli/v3"
 )
 
+type labelData struct {
+	Name        string `json:"name"`
+	Color       string `json:"color"`
+	Description string `json:"description"`
+}
+
+type issueData struct {
+	ID        int64           `json:"id"`
+	Index     int64           `json:"index"`
+	Title     string          `json:"title"`
+	State     gitea.StateType `json:"state"`
+	Created   time.Time       `json:"created"`
+	Labels    []labelData     `json:"labels"`
+	User      string          `json:"user"`
+	Body      string          `json:"body"`
+	Assignees []string        `json:"assignees"`
+	URL       string          `json:"url"`
+	ClosedAt  *time.Time      `json:"closedAt"`
+	Comments  []commentData   `json:"comments"`
+}
+
+type commentData struct {
+	ID      int64     `json:"id"`
+	Author  string    `json:"author"`
+	Created time.Time `json:"created"`
+	Body    string    `json:"body"`
+}
+
 // CmdIssues represents to login a gitea server.
 var CmdIssues = cli.Command{
 	Name:        "issues",
@@ -64,6 +96,14 @@ func runIssueDetail(_ stdctx.Context, cmd *cli.Command, index string) error {
 	if err != nil {
 		return err
 	}
+
+	if ctx.IsSet("output") {
+		switch ctx.String("output") {
+		case "json":
+			return runIssueDetailAsJSON(ctx, issue)
+		}
+	}
+
 	print.IssueDetails(issue, reactions)
 
 	if issue.Comments > 0 {
@@ -75,3 +115,61 @@ func runIssueDetail(_ stdctx.Context, cmd *cli.Command, index string) error {
 
 	return nil
 }
+
+func runIssueDetailAsJSON(ctx *context.TeaContext, issue *gitea.Issue) error {
+	c := ctx.Login.Client()
+	opts := gitea.ListIssueCommentOptions{ListOptions: flags.GetListOptions()}
+
+	labelSlice := make([]labelData, 0, len(issue.Labels))
+	for _, label := range issue.Labels {
+		labelSlice = append(labelSlice, labelData{label.Name, label.Color, label.Description})
+	}
+
+	assigneesSlice := make([]string, 0, len(issue.Assignees))
+	for _, assignee := range issue.Assignees {
+		assigneesSlice = append(assigneesSlice, assignee.UserName)
+	}
+
+	issueSlice := issueData{
+		ID:        issue.ID,
+		Index:     issue.Index,
+		Title:     issue.Title,
+		State:     issue.State,
+		Created:   issue.Created,
+		User:      issue.Poster.UserName,
+		Body:      issue.Body,
+		Labels:    labelSlice,
+		Assignees: assigneesSlice,
+		URL:       issue.HTMLURL,
+		ClosedAt:  issue.Closed,
+		Comments:  make([]commentData, 0),
+	}
+
+	if ctx.Bool("comments") {
+		comments, _, err := c.ListIssueComments(ctx.Owner, ctx.Repo, issue.Index, opts)
+		issueSlice.Comments = make([]commentData, 0, len(comments))
+
+		if err != nil {
+			return err
+		}
+
+		for _, comment := range comments {
+			issueSlice.Comments = append(issueSlice.Comments, commentData{
+				ID:      comment.ID,
+				Author:  comment.Poster.UserName,
+				Body:    comment.Body, // Selected Field
+				Created: comment.Created,
+			})
+		}
+
+	}
+
+	jsonData, err := json.MarshalIndent(issueSlice, "", "\t")
+	if err != nil {
+		return err
+	}
+
+	_, err = fmt.Fprintf(ctx.Writer, "%s\n", jsonData)
+
+	return err
+}

cmd/issues_test.go

@@ -0,0 +1,270 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package cmd
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"code.gitea.io/sdk/gitea"
+	"code.gitea.io/tea/modules/config"
+	"code.gitea.io/tea/modules/context"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"github.com/urfave/cli/v3"
+)
+
+const (
+	testOwner = "testOwner"
+	testRepo  = "testRepo"
+)
+
+func createTestIssue(comments int, isClosed bool) gitea.Issue {
+	var issue = gitea.Issue{
+		ID:      42,
+		Index:   1,
+		Title:   "Test issue",
+		State:   gitea.StateOpen,
+		Body:    "This is a test",
+		Created: time.Date(2025, 31, 10, 23, 59, 59, 999999999, time.UTC),
+		Updated: time.Date(2025, 1, 11, 0, 0, 0, 0, time.UTC),
+		Labels: []*gitea.Label{
+			{
+				Name:        "example/Label1",
+				Color:       "very red",
+				Description: "This is an example label",
+			},
+			{
+				Name:        "example/Label2",
+				Color:       "hardly red",
+				Description: "This is another example label",
+			},
+		},
+		Comments: comments,
+		Poster: &gitea.User{
+			UserName: "testUser",
+		},
+		Assignees: []*gitea.User{
+			{UserName: "testUser"},
+			{UserName: "testUser3"},
+		},
+		HTMLURL: "<space holder>",
+		Closed:  nil, //2025-11-10T21:20:19Z
+	}
+
+	if isClosed {
+		var closed = time.Date(2025, 11, 10, 21, 20, 19, 0, time.UTC)
+		issue.Closed = &closed
+	}
+
+	if isClosed {
+		issue.State = gitea.StateClosed
+	} else {
+		issue.State = gitea.StateOpen
+	}
+
+	return issue
+
+}
+
+func createTestIssueComments(comments int) []gitea.Comment {
+	baseID := 900
+	var result []gitea.Comment
+
+	for commentID := 0; commentID < comments; commentID++ {
+		result = append(result, gitea.Comment{
+			ID: int64(baseID + commentID),
+			Poster: &gitea.User{
+				UserName: "Freddy",
+			},
+			Body: fmt.Sprintf("This is a test comment #%v", commentID),
+			Created: time.Date(2025, 11, 3, 12, 0, 0, 0, time.UTC).
+				Add(time.Duration(commentID) * time.Hour),
+		})
+	}
+
+	return result
+
+}
+
+func TestRunIssueDetailAsJSON(t *testing.T) {
+	type TestCase struct {
+		name         string
+		issue        gitea.Issue
+		comments     []gitea.Comment
+		flagComments bool
+		flagOutput   string
+		flagOut      string
+		closed       bool
+	}
+
+	cmd := cli.Command{
+		Name: "t",
+		Flags: []cli.Flag{
+			&cli.BoolFlag{
+				Name:  "comments",
+				Value: false,
+			},
+			&cli.StringFlag{
+				Name:  "output",
+				Value: "json",
+			},
+		},
+	}
+
+	testContext := context.TeaContext{
+		Owner: testOwner,
+		Repo:  testRepo,
+		Login: &config.Login{
+			Name: "testLogin",
+			URL:  "http://127.0.0.1:8081",
+		},
+		Command: &cmd,
+	}
+
+	testCases := []TestCase{
+		{
+			name:         "Simple issue with no comments, no comments requested",
+			issue:        createTestIssue(0, true),
+			comments:     []gitea.Comment{},
+			flagComments: false,
+		},
+		{
+			name:         "Simple issue with no comments, comments requested",
+			issue:        createTestIssue(0, true),
+			comments:     []gitea.Comment{},
+			flagComments: true,
+		},
+		{
+			name:         "Simple issue with comments, no comments requested",
+			issue:        createTestIssue(2, true),
+			comments:     createTestIssueComments(2),
+			flagComments: false,
+		},
+		{
+			name:         "Simple issue with comments, comments requested",
+			issue:        createTestIssue(2, true),
+			comments:     createTestIssueComments(2),
+			flagComments: true,
+		},
+		{
+			name:         "Simple issue with comments, comments requested, not closed",
+			issue:        createTestIssue(2, false),
+			comments:     createTestIssueComments(2),
+			flagComments: true,
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				path := r.URL.Path
+				if path == fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/comments", testOwner, testRepo, testCase.issue.Index) {
+					jsonComments, err := json.Marshal(testCase.comments)
+					if err != nil {
+						require.NoError(t, err, "Testing setup failed: failed to marshal comments")
+					}
+					w.Header().Set("Content-Type", "application/json")
+					w.WriteHeader(http.StatusOK)
+					_, err = w.Write(jsonComments)
+					require.NoError(t, err, "Testing setup failed: failed to write out comments")
+				} else {
+					http.NotFound(w, r)
+				}
+			})
+
+			server := httptest.NewServer(handler)
+
+			testContext.Login.URL = server.URL
+			testCase.issue.HTMLURL = fmt.Sprintf("%s/%s/%s/issues/%d/", testContext.Login.URL, testOwner, testRepo, testCase.issue.Index)
+
+			var outBuffer bytes.Buffer
+			testContext.Writer = &outBuffer
+			var errBuffer bytes.Buffer
+			testContext.ErrWriter = &errBuffer
+
+			if testCase.flagComments {
+				_ = testContext.Command.Set("comments", "true")
+			} else {
+				_ = testContext.Command.Set("comments", "false")
+			}
+
+			err := runIssueDetailAsJSON(&testContext, &testCase.issue)
+
+			server.Close()
+
+			require.NoError(t, err, "Failed to run issue detail as JSON")
+
+			out := outBuffer.String()
+
+			require.NotEmpty(t, out, "Unexpected empty output from runIssueDetailAsJSON")
+
+			//setting expectations
+
+			var expectedLabels []labelData
+			expectedLabels = []labelData{}
+			for _, l := range testCase.issue.Labels {
+				expectedLabels = append(expectedLabels, labelData{
+					Name:        l.Name,
+					Color:       l.Color,
+					Description: l.Description,
+				})
+			}
+
+			var expectedAssignees []string
+			expectedAssignees = []string{}
+			for _, a := range testCase.issue.Assignees {
+				expectedAssignees = append(expectedAssignees, a.UserName)
+			}
+
+			var expectedClosedAt *time.Time
+			if testCase.issue.Closed != nil {
+				expectedClosedAt = testCase.issue.Closed
+			}
+
+			var expectedComments []commentData
+			expectedComments = []commentData{}
+			if testCase.flagComments {
+				for _, c := range testCase.comments {
+					expectedComments = append(expectedComments, commentData{
+						ID:      c.ID,
+						Author:  c.Poster.UserName,
+						Body:    c.Body,
+						Created: c.Created,
+					})
+				}
+			}
+
+			expected := issueData{
+				ID:        testCase.issue.ID,
+				Index:     testCase.issue.Index,
+				Title:     testCase.issue.Title,
+				State:     testCase.issue.State,
+				Created:   testCase.issue.Created,
+				User:      testCase.issue.Poster.UserName,
+				Body:      testCase.issue.Body,
+				URL:       testCase.issue.HTMLURL,
+				ClosedAt:  expectedClosedAt,
+				Labels:    expectedLabels,
+				Assignees: expectedAssignees,
+				Comments:  expectedComments,
+			}
+
+			// validating reality
+			var actual issueData
+			dec := json.NewDecoder(bytes.NewReader(outBuffer.Bytes()))
+			dec.DisallowUnknownFields()
+			err = dec.Decode(&actual)
+			require.NoError(t, err, "Failed to unmarshal output into struct")
+
+			assert.Equal(t, expected, actual, "Expected structs differ from expected one")
+		})
+	}
+
+}