Add pagination headers on endpoints that support total count from database (#11145)

* begin work

* import fmt

* more work

* empty commit

Co-authored-by: Lauris BH <lauris@nix.lv>

routers/api/v1/user/user.go

@@ -6,6 +6,7 @@
 package user
 
 import (
+	"fmt"
 	"net/http"
 	"strings"
 
@@ -56,14 +57,16 @@ func Search(ctx *context.APIContext) {
 	//           items:
 	//             "$ref": "#/definitions/User"
 
+	listOptions := utils.GetListOptions(ctx)
+
 	opts := &models.SearchUserOptions{
 		Keyword:     strings.Trim(ctx.Query("q"), " "),
 		UID:         com.StrTo(ctx.Query("uid")).MustInt64(),
 		Type:        models.UserTypeIndividual,
-		ListOptions: utils.GetListOptions(ctx),
+		ListOptions: listOptions,
 	}
 
-	users, _, err := models.SearchUsers(opts)
+	users, maxResults, err := models.SearchUsers(opts)
 	if err != nil {
 		ctx.JSON(http.StatusInternalServerError, map[string]interface{}{
 			"ok":    false,
@@ -77,6 +80,9 @@ func Search(ctx *context.APIContext) {
 		results[i] = convert.ToUser(users[i], ctx.IsSigned, ctx.User != nil && ctx.User.IsAdmin)
 	}
 
+	ctx.SetLinkHeader(int(maxResults), listOptions.PageSize)
+	ctx.Header().Set("X-Total-Count", fmt.Sprintf("%d", maxResults))
+
 	ctx.JSON(http.StatusOK, map[string]interface{}{
 		"ok":   true,
 		"data": results,