[API] generalize list header (#16551)

* Add info about list endpoints to CONTRIBUTING.md

* Let all list endpoints return X-Total-Count header 

* Add TODOs for GetCombinedCommitStatusByRef

* Fix models/issue_stopwatch.go

* Rrefactor models.ListDeployKeys

* Introduce helper func and use them for SetLinkHeader related func

4 files changed, 9 insertions, 13 deletions

diff --git a/routers/api/v1/admin/adopt.go b/routers/api/v1/admin/adopt.go
index 062cee6283..9c1b9fc0f8 100644
--- a/routers/api/v1/admin/adopt.go
+++ b/routers/api/v1/admin/adopt.go
@@ -5,7 +5,6 @@
 package admin
 
 import (
-	"fmt"
 	"net/http"
 
 	"code.gitea.io/gitea/models"
@@ -47,8 +46,7 @@ func ListUnadoptedRepositories(ctx *context.APIContext) {
 		ctx.InternalServerError(err)
 	}
 
-	ctx.Header().Set("X-Total-Count", fmt.Sprintf("%d", count))
-	ctx.Header().Set("Access-Control-Expose-Headers", "X-Total-Count")
+	ctx.SetTotalCountHeader(int64(count))
 
 	ctx.JSON(http.StatusOK, repoNames)
 }
diff --git a/routers/api/v1/admin/cron.go b/routers/api/v1/admin/cron.go
index 2531346fcb..970fad8388 100644
--- a/routers/api/v1/admin/cron.go
+++ b/routers/api/v1/admin/cron.go
@@ -11,6 +11,7 @@ import (
 	"code.gitea.io/gitea/modules/cron"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/structs"
+	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/routers/api/v1/utils"
 )
 
@@ -36,12 +37,10 @@ func ListCronTasks(ctx *context.APIContext) {
 	//   "403":
 	//     "$ref": "#/responses/forbidden"
 	tasks := cron.ListTasks()
-	listOpts := utils.GetListOptions(ctx)
-	start, end := listOpts.GetStartEnd()
+	count := len(tasks)
 
-	if len(tasks) > listOpts.PageSize {
-		tasks = tasks[start:end]
-	}
+	listOpts := utils.GetListOptions(ctx)
+	tasks = util.PaginateSlice(tasks, listOpts.Page, listOpts.PageSize).(cron.TaskTable)
 
 	res := make([]structs.Cron, len(tasks))
 	for i, task := range tasks {
@@ -53,6 +52,8 @@ func ListCronTasks(ctx *context.APIContext) {
 			ExecTimes: task.ExecTimes,
 		}
 	}
+
+	ctx.SetTotalCountHeader(int64(count))
 	ctx.JSON(http.StatusOK, res)
 }
 
diff --git a/routers/api/v1/admin/org.go b/routers/api/v1/admin/org.go
index 1356276f07..f1a766d544 100644
--- a/routers/api/v1/admin/org.go
+++ b/routers/api/v1/admin/org.go
@@ -6,7 +6,6 @@
 package admin
 
 import (
-	"fmt"
 	"net/http"
 
 	"code.gitea.io/gitea/models"
@@ -121,7 +120,6 @@ func GetAllOrgs(ctx *context.APIContext) {
 	}
 
 	ctx.SetLinkHeader(int(maxResults), listOptions.PageSize)
-	ctx.Header().Set("X-Total-Count", fmt.Sprintf("%d", maxResults))
-	ctx.Header().Set("Access-Control-Expose-Headers", "X-Total-Count, Link")
+	ctx.SetTotalCountHeader(maxResults)
 	ctx.JSON(http.StatusOK, &orgs)
 }
diff --git a/routers/api/v1/admin/user.go b/routers/api/v1/admin/user.go
index 6bc9b849b1..e5a75da759 100644
--- a/routers/api/v1/admin/user.go
+++ b/routers/api/v1/admin/user.go
@@ -423,7 +423,6 @@ func GetAllUsers(ctx *context.APIContext) {
 	}
 
 	ctx.SetLinkHeader(int(maxResults), listOptions.PageSize)
-	ctx.Header().Set("X-Total-Count", fmt.Sprintf("%d", maxResults))
-	ctx.Header().Set("Access-Control-Expose-Headers", "X-Total-Count, Link")
+	ctx.SetTotalCountHeader(maxResults)
 	ctx.JSON(http.StatusOK, &results)
 }