graphql: lazy loading for the bug relay connection

1 files changed, 44 insertions, 1 deletions

diff --git a/graphql/resolvers/repo.go b/graphql/resolvers/repo.go
index d8190f15..2031d7b6 100644
--- a/graphql/resolvers/repo.go
+++ b/graphql/resolvers/repo.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"github.com/MichaelMure/git-bug/bug"
 	"github.com/MichaelMure/git-bug/cache"
+	"github.com/MichaelMure/git-bug/graphql/connections"
 	"github.com/MichaelMure/git-bug/graphql/models"
 )
 
@@ -13,7 +14,49 @@ type repoResolver struct {
 }
 
 func (repoResolver) AllBugs(ctx context.Context, obj *repoResolver, input models.ConnectionInput) (models.BugConnection, error) {
-	panic("implement me")
+
+	// Simply pass a []string with the ids to the pagination algorithm
+	source, err := obj.repo.AllBugIds()
+
+	if err != nil {
+		return models.BugConnection{}, err
+	}
+
+	// The edger create a custom edge holding just the id
+	edger := func(id string, offset int) connections.Edge {
+		return connections.LazyBugEdge{
+			Id:     id,
+			Cursor: connections.OffsetToCursor(offset),
+		}
+	}
+
+	// The conMaker will finally load and compile bugs from git to replace the selected edges
+	conMaker := func(lazyBugEdges []connections.LazyBugEdge, info models.PageInfo, totalCount int) (models.BugConnection, error) {
+		edges := make([]models.BugEdge, len(lazyBugEdges))
+
+		for i, lazyBugEdge := range lazyBugEdges {
+			b, err := obj.repo.ResolveBug(lazyBugEdge.Id)
+
+			if err != nil {
+				return models.BugConnection{}, err
+			}
+
+			snap := b.Snapshot()
+
+			edges[i] = models.BugEdge{
+				Cursor: lazyBugEdge.Cursor,
+				Node:   *snap,
+			}
+		}
+
+		return models.BugConnection{
+			Edges:      edges,
+			PageInfo:   info,
+			TotalCount: totalCount,
+		}, nil
+	}
+
+	return connections.StringCon(source, edger, conMaker, input)
 }
 
 func (repoResolver) Bug(ctx context.Context, obj *repoResolver, prefix string) (*bug.Snapshot, error) {