From ef0d8fa108fbdef24997a84a3c6ecbf21cbc0a9e Mon Sep 17 00:00:00 2001
From: Michael Muré <batolettre@gmail.com>
Date: Tue, 14 Aug 2018 13:32:03 +0200
Subject: graphql: expose startCursor and endCursor as well for a connection

---
 graphql/connections/connection_template.go | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

(limited to 'graphql/connections/connection_template.go')

diff --git a/graphql/connections/connection_template.go b/graphql/connections/connection_template.go
index 511f48d3..523141cd 100644
--- a/graphql/connections/connection_template.go
+++ b/graphql/connections/connection_template.go
@@ -16,9 +16,9 @@ type EdgeType generic.Type
 // ConnectionType define the connection type handled by this relay connection
 type ConnectionType generic.Type
 
-// NodeTypeEdger define a function that take a NodeType and an offset and
+// NodeTypeEdgeMaker define a function that take a NodeType and an offset and
 // create an Edge.
-type NodeTypeEdger func(value NodeType, offset int) Edge
+type NodeTypeEdgeMaker func(value NodeType, offset int) Edge
 
 // NodeTypeConMaker define a function that create a ConnectionType
 type NodeTypeConMaker func(
@@ -28,9 +28,10 @@ type NodeTypeConMaker func(
 	totalCount int) (ConnectionType, error)
 
 // NodeTypeCon will paginate a source according to the input of a relay connection
-func NodeTypeCon(source []NodeType, edger NodeTypeEdger, conMaker NodeTypeConMaker, input models.ConnectionInput) (ConnectionType, error) {
+func NodeTypeCon(source []NodeType, edgeMaker NodeTypeEdgeMaker, conMaker NodeTypeConMaker, input models.ConnectionInput) (ConnectionType, error) {
 	var nodes []NodeType
 	var edges []EdgeType
+	var cursors []string
 	var pageInfo models.PageInfo
 
 	emptyCon, _ := conMaker(edges, nodes, pageInfo, 0)
@@ -39,7 +40,7 @@ func NodeTypeCon(source []NodeType, edger NodeTypeEdger, conMaker NodeTypeConMak
 
 	if input.After != nil {
 		for i, value := range source {
-			edge := edger(value, i)
+			edge := edgeMaker(value, i)
 			if edge.GetCursor() == *input.After {
 				// remove all previous element including the "after" one
 				source = source[i+1:]
@@ -51,7 +52,7 @@ func NodeTypeCon(source []NodeType, edger NodeTypeEdger, conMaker NodeTypeConMak
 
 	if input.Before != nil {
 		for i, value := range source {
-			edge := edger(value, i+offset)
+			edge := edgeMaker(value, i+offset)
 
 			if edge.GetCursor() == *input.Before {
 				// remove all after element including the "before" one
@@ -59,14 +60,18 @@ func NodeTypeCon(source []NodeType, edger NodeTypeEdger, conMaker NodeTypeConMak
 			}
 
 			edges = append(edges, edge.(EdgeType))
+			cursors = append(cursors, edge.GetCursor())
 			nodes = append(nodes, value)
 		}
 	} else {
 		edges = make([]EdgeType, len(source))
+		cursors = make([]string, len(source))
 		nodes = source
 
 		for i, value := range source {
-			edges[i] = edger(value, i+offset).(EdgeType)
+			edge := edgeMaker(value, i+offset)
+			edges[i] = edge.(EdgeType)
+			cursors[i] = edge.GetCursor()
 		}
 	}
 
@@ -78,6 +83,7 @@ func NodeTypeCon(source []NodeType, edger NodeTypeEdger, conMaker NodeTypeConMak
 		if len(edges) > *input.First {
 			// Slice result to be of length first by removing edges from the end
 			edges = edges[:*input.First]
+			cursors = cursors[:*input.First]
 			nodes = nodes[:*input.First]
 			pageInfo.HasNextPage = true
 		}
@@ -91,10 +97,17 @@ func NodeTypeCon(source []NodeType, edger NodeTypeEdger, conMaker NodeTypeConMak
 		if len(edges) > *input.Last {
 			// Slice result to be of length last by removing edges from the start
 			edges = edges[len(edges)-*input.Last:]
+			cursors = cursors[len(cursors)-*input.Last:]
 			nodes = nodes[len(nodes)-*input.Last:]
 			pageInfo.HasPreviousPage = true
 		}
 	}
 
+	// Fill up pageInfo cursors
+	if len(cursors) > 0 {
+		pageInfo.StartCursor = cursors[0]
+		pageInfo.EndCursor = cursors[len(cursors)-1]
+	}
+
 	return conMaker(edges, nodes, pageInfo, len(source))
 }
-- 
cgit