Merge pull request #9 from hatch-is/add-count-headres

Add count headres

Author: andreychuk

model/articles.go

@@ -15,35 +15,26 @@ import (
 type ArticlesModel struct{}
 
 //Read get articles
-func (artModel *ArticlesModel) Read(qFilter string, qSkip string, qLimit string) (result []store.Article, err error) {
+func (artModel *ArticlesModel) Read(qFilter string) (result []store.Article, total int, left int, err error) {
 	artDb := store.ArticlesCollectionConnect()
 
 	query, isSort, err := artModel.convertFilter(qFilter)
 	if err != nil {
 		return
 	}
+	skip, limit := getSkipLimit(qFilter)
 	query["deleted"] = false
 	if isSort == false {
-
 		fields := bson.M{}
-
-		skip, err := strconv.Atoi(qSkip)
-		if err != nil {
-			skip = 0
-		}
-		limit, err := strconv.Atoi(qLimit)
-		if err != nil {
-			limit = 0
-		}
-		result, err = artDb.Read(query, fields, skip, limit)
+		result, total, left, err = artDb.Read(query, fields, skip, limit)
 	} else {
-		result, err = artDb.Search(query)
+		result, total, left, err = artDb.Search(query, skip, limit)
 	}
 
 	if err != nil {
 		return
 	}
-	return result, nil
+	return result, total, left, nil
 }
 
 //ReadOne get article by ID
@@ -172,3 +163,27 @@ func (artModel *ArticlesModel) Delete(qID string) (err error) {
 
 	return
 }
+
+func getSkipLimit(filter string) (skip int, limit int) {
+	if filter != "" {
+		jParser, err := gabs.ParseJSON([]byte(filter))
+		if err != nil {
+			return
+		}
+
+		if s := jParser.Exists("skip"); s == true {
+			sTmp, ok := jParser.Path("skip").Data().(string)
+			if ok == true {
+				skip, _ = strconv.Atoi(sTmp)
+			}
+		}
+
+		if l := jParser.Exists("limit"); l == true {
+			lTmp, ok := jParser.Path("limit").Data().(string)
+			if ok == true {
+				limit, _ = strconv.Atoi(lTmp)
+			}
+		}
+	}
+	return skip, limit
+}

store/articles.go

@@ -51,20 +51,27 @@ func ArticlesCollectionConnect() *ArticlesCollection {
 }
 
 //Read return entries of Articles collections
-func (art *ArticlesCollection) Read(query bson.M, fields bson.M, skip int, limit int) (result []Article, err error) {
+func (art *ArticlesCollection) Read(query bson.M, fields bson.M, skip int, limit int) (result []Article, total int, left int, err error) {
 	session, artCollection, err := art.conn.getSessionAndCollection(art.collection)
 	if err != nil {
 		return
 	}
 	defer session.Close()
 	result = make([]Article, 0)
 	err = artCollection.Find(query).Select(fields).Skip(skip).Limit(limit).All(&result)
-
 	if err != nil {
 		return
 	}
-
-	return result, nil
+	count := len(result)
+	total, err = artCollection.Find(query).Count()
+	if err != nil {
+		return
+	}
+	left = total - (skip + count)
+	if left < 0 {
+		left = 0
+	}
+	return result, total, left, nil
 }
 
 //ReadOne return one enrty of Articles collection by query
@@ -161,7 +168,7 @@ func (art *ArticlesCollection) Delete(ID bson.ObjectId) (err error) {
 }
 
 //Search implement full-text search
-func (art *ArticlesCollection) Search(q bson.M) (result []Article, err error) {
+func (art *ArticlesCollection) Search(q bson.M, skip int, limit int) (result []Article, total int, left int, err error) {
 	session, artCollection, err := art.conn.getSessionAndCollection(art.collection)
 	if err != nil {
 		return
@@ -175,10 +182,22 @@ func (art *ArticlesCollection) Search(q bson.M) (result []Article, err error) {
 	}
 	sort := "$textScore:score"
 	result = make([]Article, 0)
-	err = artCollection.Find(q).Select(fields).Sort(sort).All(&result)
+	err = artCollection.Find(q).Select(fields).Sort(sort).Skip(skip).Limit(limit).All(&result)
+	if err != nil {
+		return
+	}
+	count := len(result)
+	total, err = artCollection.Find(q).Select(fields).Sort(sort).Count()
+	if err != nil {
+		return
+	}
+	left = total - (skip + count)
+	if left < 0 {
+		left = 0
+	}
 	if err != nil {
 		return
 	}
 
-	return result, nil
+	return result, total, left, nil
 }

webActions/articlesWebActions.go

@@ -3,6 +3,7 @@ package webActions
 import (
 	"knowledge-base/model"
 	"net/http"
+	"strconv"
 
 	"github.com/gorilla/mux"
 )
@@ -14,11 +15,11 @@ type ArticlesWebActions struct {
 
 //Read get all articles
 func (art *ArticlesWebActions) Read(w http.ResponseWriter, r *http.Request) {
-	skip := r.URL.Query().Get("skip")
-	limit := r.URL.Query().Get("limit")
 	filter := r.URL.Query().Get("filter")
 
-	data, err := art.model.Read(filter, skip, limit)
+	data, total, left, err := art.model.Read(filter)
+	w.Header().Set("X-Total-Count", strconv.Itoa(total))
+	w.Header().Set("X-RateLimit-Remaining", strconv.Itoa(left))
 	if err != nil {
 		ErrorWithJSON(w, r, err.Error(), 404)
 	} else {