pulumi/pkg/graph/graph.go
2017-06-26 14:46:34 -07:00

36 lines
1.9 KiB
Go

// Copyright 2016-2017, Pulumi Corporation. All rights reserved.
// Package graph defines LumiGL graphs. Each graph is directed and acyclic, and the nodes have been topologically
// sorted based on dependencies (edges) between them. Each node in the graph has a type and a set of properties.
//
// There are two forms of graph: complete and incomplete. A complete graph is one in which all nodes and their property
// values are known. An incomplete graph is one where two uncertainties may arise: (1) an edge might be "conditional",
// indicating that its presence or absence is dependent on a piece of information not yet available (like an output
// property from a resource), and/or (2) a property may either be similarly conditional or computed as an output value.
//
// In general, LumiPacks may be evaluated to produce graphs. These may then be compared to other graphs to produce
// and/or carry out deployment plans. This package therefore also exposes operations necessary for diffing graphs.
package graph
// Graph is an instance of a LumiGL digraph. Each is associated with a single LumiPack as its input, along
// with a set of optional arguments used to evaluate it, along with the output DAG with node types and properties.
type Graph interface {
Roots() []Edge // the root edges.
}
// Vertex is a single vertex within an overall LumiGL graph.
type Vertex interface {
Data() interface{} // arbitrary data associated with this vertex.
Label() string // the vertex's label.
Ins() []Edge // incoming edges from other vertices within the graph to this vertex.
Outs() []Edge // outgoing edges from this vertex to other vertices within the graph.
}
// Edge is a directed edge from one vertex to another.
type Edge interface {
Data() interface{} // arbitrary data associated with this edge.
Label() string // this edge's label.
To() Vertex // the vertex this edge connects to.
From() Vertex // the vertex this edge connects from.
}