Added issue search via api (#3612)

* Started implementing issue api search

* Implemented issue search via api

* Added search to swagger.json

* Removed todo

* fmt

* Added comment to generate swagger json via "generate-swagger"

* Simplified search

* fmt

* Removed unessecary comment

* Removed unessecary declaration of the issues-variable

* Removed unessecary comment

* Removed unessecary comment

* Added explanation keyword

* Simplified check for empty keyword

* corrected check if keyword is empty

public/swagger.v1.json

@@ -1830,6 +1830,12 @@
             "description": "page number of requested issues",
             "name": "page",
             "in": "query"
+          },
+          {
+            "type": "string",
+            "description": "search string",
+            "name": "q",
+            "in": "query"
           }
         ],
         "responses": {

routers/api/v1/repo/issue.go

@@ -12,6 +12,7 @@ import (
 
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/indexer"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/util"
 )
@@ -42,6 +43,10 @@ func ListIssues(ctx *context.APIContext) {
 	//   in: query
 	//   description: page number of requested issues
 	//   type: integer
+	// - name: q
+	//   in: query
+	//   description: search string
+	//   type: string
 	// responses:
 	//   "200":
 	//     "$ref": "#/responses/IssueList"
@@ -55,12 +60,30 @@ func ListIssues(ctx *context.APIContext) {
 		isClosed = util.OptionalBoolFalse
 	}
 
-	issues, err := models.Issues(&models.IssuesOptions{
+	var issues []*models.Issue
+
+	keyword := strings.Trim(ctx.Query("q"), " ")
+	if strings.IndexByte(keyword, 0) >= 0 {
+		keyword = ""
+	}
+	var issueIDs []int64
+	var err error
+	if len(keyword) > 0 {
+		issueIDs, err = indexer.SearchIssuesByKeyword(ctx.Repo.Repository.ID, keyword)
+	}
+
+	// Only fetch the issues if we either don't have a keyword or the search returned issues
+	// This would otherwise return all issues if no issues were found by the search.
+	if len(keyword) == 0 || len(issueIDs) > 0 {
+		issues, err = models.Issues(&models.IssuesOptions{
 			RepoIDs:  []int64{ctx.Repo.Repository.ID},
 			Page:     ctx.QueryInt("page"),
 			PageSize: setting.UI.IssuePagingNum,
 			IsClosed: isClosed,
+			IssueIDs: issueIDs,
 		})
+	}
+
 	if err != nil {
 		ctx.Error(500, "Issues", err)
 		return