fixing pagination

Author: ad3n

handlers/handler.go

@@ -35,7 +35,7 @@ func (h *Handler) Paginate(paginator paginations.Pagination) (paginations.Pagina
 	})
 
 	var result []interface{}
-	adapter := adapter.NewElasticsearchAdapter(h.Context, h.Elasticsearch, paginator.Model, query)
+	adapter := adapter.NewElasticsearchAdapter(h.Context, h.Elasticsearch, paginator.Model, paginator.UseCounter, paginator.Counter, query)
 	paginator.Paginate(adapter)
 	paginator.Pager.Results(&result)
 	next := paginator.Page + 1

paginations/adapter/elasticsearch.go

@@ -14,19 +14,23 @@ type (
 		context    context.Context
 		client     *elastic.Client
 		index      string
+		counter    uint64
+		useCounter bool
 		pageQuery  *elastic.BoolQuery
 		totalQuery *elastic.BoolQuery
 	}
 )
 
-func NewElasticsearchAdapter(context context.Context, client *elastic.Client, index string, query *elastic.BoolQuery) paginator.Adapter {
+func NewElasticsearchAdapter(context context.Context, client *elastic.Client, index string, useCounter bool, counter uint64, query *elastic.BoolQuery) paginator.Adapter {
 	totalQuery := elastic.NewBoolQuery()
 	*totalQuery = *query
 
 	return &ElasticsearchAdapter{
 		context:    context,
 		client:     client,
 		index:      index,
+		useCounter: useCounter,
+		counter:    counter,
 		pageQuery:  query,
 		totalQuery: totalQuery,
 	}
@@ -43,9 +47,12 @@ func (es *ElasticsearchAdapter) Nums() (int64, error) {
 }
 
 func (es *ElasticsearchAdapter) Slice(offset int, length int, data interface{}) error {
-	es.pageQuery.Must(elastic.NewRangeQuery("Counter").From(offset).To(length + offset))
+	if es.useCounter {
+		es.pageQuery.Must(elastic.NewRangeQuery("Counter").From(es.counter).To(es.counter + uint64(length)))
+		offset = 0
+	}
 
-	result, err := es.client.Search().Index(es.index).IgnoreUnavailable(true).Query(es.pageQuery).Size(length).Do(es.context)
+	result, err := es.client.Search().Index(es.index).IgnoreUnavailable(true).Query(es.pageQuery).From(offset).Size(length).Do(es.context)
 	if err != nil {
 		log.Printf("%s", err.Error())
 		return nil

paginations/pagination.go

@@ -14,12 +14,14 @@ type (
 	}
 
 	Pagination struct {
-		Limit   int
-		Page    int
-		Filters []Filter
-		Search  string
-		Pager   paginator.Paginator
-		Model   string
+		Limit      int
+		Page       int
+		UseCounter bool
+		Counter    uint64
+		Filters    []Filter
+		Search     string
+		Pager      paginator.Paginator
+		Model      string
 	}
 
 	PaginationMeta struct {
@@ -50,6 +52,11 @@ func (p *Pagination) Handle(pagination *grpcs.Pagination) {
 		}
 	}
 
+	if pagination.Counter > 0 {
+		p.UseCounter = true
+		p.Counter = pagination.Counter
+	}
+
 	p.Limit = int(pagination.Limit)
 	p.Page = int(pagination.Page)
 }

protos/builds/pagination.pb.go

@@ -15,7 +15,8 @@ message PaginationMetadata {
 
 message Pagination {
     int32 page = 1;
-    int32 limit = 2;
-    repeated string fields = 3;
-    repeated string values = 4;
+    uint64 counter = 2;
+    int32 limit = 3;
+    repeated string fields = 4;
+    repeated string values = 5;
 }