3 files changed, 137 insertions, 0 deletions

diff --git a/modules/context/repo.go b/modules/context/repo.go
index 4aac0c05aa..2c77361460 100644
--- a/modules/context/repo.go
+++ b/modules/context/repo.go
@@ -16,13 +16,27 @@ import (
 	"code.gitea.io/gitea/modules/cache"
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/markup/markdown"
 	"code.gitea.io/gitea/modules/setting"
+	api "code.gitea.io/gitea/modules/structs"
 
 	"gitea.com/macaron/macaron"
 	"github.com/editorconfig/editorconfig-core-go/v2"
 	"github.com/unknwon/com"
 )
 
+// IssueTemplateDirCandidates issue templates directory
+var IssueTemplateDirCandidates = []string{
+	"ISSUE_TEMPLATE",
+	"issue_template",
+	".gitea/ISSUE_TEMPLATE",
+	".gitea/issue_template",
+	".github/ISSUE_TEMPLATE",
+	".github/issue_template",
+	".gitlab/ISSUE_TEMPLATE",
+	".gitlab/issue_template",
+}
+
 // PullRequest contains informations to make a pull request
 type PullRequest struct {
 	BaseRepo *models.Repository
@@ -821,3 +835,60 @@ func UnitTypes() macaron.Handler {
 		ctx.Data["UnitTypeProjects"] = models.UnitTypeProjects
 	}
 }
+
+// IssueTemplatesFromDefaultBranch checks for issue templates in the repo's default branch
+func (ctx *Context) IssueTemplatesFromDefaultBranch() []api.IssueTemplate {
+	var issueTemplates []api.IssueTemplate
+	if ctx.Repo.Commit == nil {
+		var err error
+		ctx.Repo.Commit, err = ctx.Repo.GitRepo.GetBranchCommit(ctx.Repo.Repository.DefaultBranch)
+		if err != nil {
+			return issueTemplates
+		}
+	}
+
+	for _, dirName := range IssueTemplateDirCandidates {
+		tree, err := ctx.Repo.Commit.SubTree(dirName)
+		if err != nil {
+			continue
+		}
+		entries, err := tree.ListEntries()
+		if err != nil {
+			return issueTemplates
+		}
+		for _, entry := range entries {
+			if strings.HasSuffix(entry.Name(), ".md") {
+				if entry.Blob().Size() >= setting.UI.MaxDisplayFileSize {
+					log.Debug("Issue template is too large: %s", entry.Name())
+					continue
+				}
+				r, err := entry.Blob().DataAsync()
+				if err != nil {
+					log.Debug("DataAsync: %v", err)
+					continue
+				}
+				defer r.Close()
+				data, err := ioutil.ReadAll(r)
+				if err != nil {
+					log.Debug("ReadAll: %v", err)
+					continue
+				}
+				var it api.IssueTemplate
+				content, err := markdown.ExtractMetadata(string(data), &it)
+				if err != nil {
+					log.Debug("ExtractMetadata: %v", err)
+					continue
+				}
+				it.Content = content
+				it.FileName = entry.Name()
+				if it.Valid() {
+					issueTemplates = append(issueTemplates, it)
+				}
+			}
+		}
+		if len(issueTemplates) > 0 {
+			return issueTemplates
+		}
+	}
+	return issueTemplates
+}
diff --git a/modules/markup/markdown/meta.go b/modules/markup/markdown/meta.go
new file mode 100644
index 0000000000..ca95e4d26a
--- /dev/null
+++ b/modules/markup/markdown/meta.go
@@ -0,0 +1,49 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package markdown
+
+import (
+	"errors"
+	"strings"
+
+	"gopkg.in/yaml.v2"
+)
+
+func isYAMLSeparator(line string) bool {
+	line = strings.TrimSpace(line)
+	for i := 0; i < len(line); i++ {
+		if line[i] != '-' {
+			return false
+		}
+	}
+	return len(line) > 2
+}
+
+// ExtractMetadata consumes a markdown file, parses YAML frontmatter,
+// and returns the frontmatter metadata separated from the markdown content
+func ExtractMetadata(contents string, out interface{}) (string, error) {
+	var front, body []string
+	var seps int
+	lines := strings.Split(contents, "\n")
+	for idx, line := range lines {
+		if seps == 2 {
+			front, body = lines[:idx], lines[idx:]
+			break
+		}
+		if isYAMLSeparator(line) {
+			seps++
+			continue
+		}
+	}
+
+	if len(front) == 0 && len(body) == 0 {
+		return "", errors.New("could not determine metadata")
+	}
+
+	if err := yaml.Unmarshal([]byte(strings.Join(front, "\n")), out); err != nil {
+		return "", err
+	}
+	return strings.Join(body, "\n"), nil
+}
diff --git a/modules/structs/issue.go b/modules/structs/issue.go
index dc633dedce..54b0f31d8a 100644
--- a/modules/structs/issue.go
+++ b/modules/structs/issue.go
@@ -5,6 +5,7 @@
 package structs
 
 import (
+	"strings"
 	"time"
 )
 
@@ -119,3 +120,19 @@ type IssueDeadline struct {
 	// swagger:strfmt date-time
 	Deadline *time.Time `json:"due_date"`
 }
+
+// IssueTemplate represents an issue template for a repository
+// swagger:model
+type IssueTemplate struct {
+	Name     string   `json:"name" yaml:"name"`
+	Title    string   `json:"title" yaml:"title"`
+	About    string   `json:"about" yaml:"about"`
+	Labels   []string `json:"labels" yaml:"labels"`
+	Content  string   `json:"content" yaml:"-"`
+	FileName string   `json:"file_name" yaml:"-"`
+}
+
+// Valid checks whether an IssueTemplate is considered valid, e.g. at least name and about
+func (it IssueTemplate) Valid() bool {
+	return strings.TrimSpace(it.Name) != "" && strings.TrimSpace(it.About) != ""
+}