Thread through start and end gcs options to the gcs query (#96)

Author: ajroetker

google/store.go

@@ -132,6 +132,12 @@ func (g *GcsFS) Get(ctx context.Context, objectpath string) (cloudstorage.Object
 // If q is nil, no filtering is done.
 func (g *GcsFS) Objects(ctx context.Context, csq cloudstorage.Query) (cloudstorage.ObjectIterator, error) {
 	var q = &storage.Query{Prefix: csq.Prefix}
+	if csq.StartOffset != "" {
+		q.StartOffset = csq.StartOffset
+	}
+	if csq.EndOffset != "" {
+		q.EndOffset = csq.EndOffset
+	}
 	iter := g.gcsb().Objects(ctx, q)
 	return &objectIterator{g, ctx, iter}, nil
 }

query.go

@@ -11,12 +11,14 @@ type Filter func(objects Objects) Objects
 // `ls /my-csv-files/baseball/*`.  This is the Request, and includes the
 // PageSize, cursor/next token as well.
 type Query struct {
-	Delimiter  string   // Delimiter is most likely "/"
-	Prefix     string   // prefix (directory) to search for or object name if one file
-	Marker     string   // Next Page Marker if provided is a start next page fetch bookmark.
-	ShowHidden bool     // Show hidden files?
-	Filters    []Filter // Applied to the result sets to filter out Objects (i.e. remove objects by extension)
-	PageSize   int      // PageSize defaults to global, or you can supply an override
+	Delimiter   string   // Delimiter is most likely "/"
+	Prefix      string   // prefix (directory) to search for or object name if one file
+	StartOffset string   // (gcs only) "bar/", Only list objects lexicographically >= "bar/"
+	EndOffset   string   // (gcs only) "foo/", Only list objects lexicographically < "foo/"
+	Marker      string   // Next Page Marker if provided is a start next page fetch bookmark.
+	ShowHidden  bool     // Show hidden files?
+	Filters     []Filter // Applied to the result sets to filter out Objects (i.e. remove objects by extension)
+	PageSize    int      // PageSize defaults to global, or you can supply an override
 }
 
 // NewQuery create a query for finding files under given prefix.