458e115490
These are helper functions to merge in existing graphs into a main graph with or without adding an edge relationship between a vertex and the new graph. These are particularly useful if using mgmt as a lib to break apart units of work into functions that create sub graphs, which are then added to the main graph when they're returned.
107 lines
4.7 KiB
Go
107 lines
4.7 KiB
Go
// Mgmt
|
|
// Copyright (C) 2013-2017+ James Shubin and the project contributors
|
|
// Written by James Shubin <james@shubin.ca> and the project contributors
|
|
//
|
|
// This program is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Affero General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// This program is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Affero General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Affero General Public License
|
|
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
package pgraph
|
|
|
|
// AddGraph adds the set of edges and vertices of a graph to the existing graph.
|
|
func (g *Graph) AddGraph(graph *Graph) {
|
|
g.addEdgeVertexGraphHelper(nil, graph, nil, false, false)
|
|
}
|
|
|
|
// AddEdgeVertexGraph adds a directed edge to the graph from a vertex.
|
|
// This is useful for flattening the relationship between a subgraph and an
|
|
// existing graph, without having to run the subgraph recursively. It adds the
|
|
// maximum number of edges, creating a relationship to every vertex.
|
|
func (g *Graph) AddEdgeVertexGraph(vertex Vertex, graph *Graph, edgeGenFn func(v1, v2 Vertex) Edge) {
|
|
g.addEdgeVertexGraphHelper(vertex, graph, edgeGenFn, false, false)
|
|
}
|
|
|
|
// AddEdgeVertexGraphLight adds a directed edge to the graph from a vertex.
|
|
// This is useful for flattening the relationship between a subgraph and an
|
|
// existing graph, without having to run the subgraph recursively. It adds the
|
|
// minimum number of edges, creating a relationship to the vertices with
|
|
// indegree equal to zero.
|
|
func (g *Graph) AddEdgeVertexGraphLight(vertex Vertex, graph *Graph, edgeGenFn func(v1, v2 Vertex) Edge) {
|
|
g.addEdgeVertexGraphHelper(vertex, graph, edgeGenFn, false, true)
|
|
}
|
|
|
|
// AddEdgeGraphVertex adds a directed edge to the vertex from a graph.
|
|
// This is useful for flattening the relationship between a subgraph and an
|
|
// existing graph, without having to run the subgraph recursively. It adds the
|
|
// maximum number of edges, creating a relationship from every vertex.
|
|
func (g *Graph) AddEdgeGraphVertex(graph *Graph, vertex Vertex, edgeGenFn func(v1, v2 Vertex) Edge) {
|
|
g.addEdgeVertexGraphHelper(vertex, graph, edgeGenFn, true, false)
|
|
}
|
|
|
|
// AddEdgeGraphVertexLight adds a directed edge to the vertex from a graph.
|
|
// This is useful for flattening the relationship between a subgraph and an
|
|
// existing graph, without having to run the subgraph recursively. It adds the
|
|
// minimum number of edges, creating a relationship from the vertices with
|
|
// outdegree equal to zero.
|
|
func (g *Graph) AddEdgeGraphVertexLight(graph *Graph, vertex Vertex, edgeGenFn func(v1, v2 Vertex) Edge) {
|
|
g.addEdgeVertexGraphHelper(vertex, graph, edgeGenFn, true, true)
|
|
}
|
|
|
|
// addEdgeVertexGraphHelper is a helper function to add a directed edges to the
|
|
// graph from a vertex, or vice-versa. It operates in this reverse direction by
|
|
// specifying the reverse argument as true. It is useful for flattening the
|
|
// relationship between a subgraph and an existing graph, without having to run
|
|
// the subgraph recursively. It adds the maximum number of edges, creating a
|
|
// relationship to or from every vertex if the light argument is false, and if
|
|
// it is true, it adds the minimum number of edges, creating a relationship to
|
|
// or from the vertices with an indegree or outdegree equal to zero depending on
|
|
// if we specified reverse or not.
|
|
func (g *Graph) addEdgeVertexGraphHelper(vertex Vertex, graph *Graph, edgeGenFn func(v1, v2 Vertex) Edge, reverse, light bool) {
|
|
|
|
var degree map[Vertex]int // compute all of the in/outdegree's if needed
|
|
if light && reverse {
|
|
degree = graph.OutDegree()
|
|
} else if light { // && !reverse
|
|
degree = graph.InDegree()
|
|
}
|
|
for _, v := range graph.VerticesSorted() { // sort to help out edgeGenFn
|
|
|
|
// forward:
|
|
// we only want to add edges to indegree == 0, because every
|
|
// other vertex is a dependency of at least one of those
|
|
|
|
// reverse:
|
|
// we only want to add edges to outdegree == 0, because every
|
|
// other vertex is a pre-requisite to at least one of these
|
|
if light && degree[v] != 0 {
|
|
continue
|
|
}
|
|
|
|
g.AddVertex(v) // ensure vertex is part of the graph
|
|
|
|
if vertex != nil && reverse {
|
|
edge := edgeGenFn(v, vertex) // generate a new unique edge
|
|
g.AddEdge(v, vertex, edge)
|
|
} else if vertex != nil { // && !reverse
|
|
edge := edgeGenFn(vertex, v)
|
|
g.AddEdge(vertex, v, edge)
|
|
}
|
|
}
|
|
|
|
// also remember to suck in all of the graph's edges too!
|
|
for v1 := range graph.Adjacency() {
|
|
for v2, e := range graph.Adjacency()[v1] {
|
|
g.AddEdge(v1, v2, e)
|
|
}
|
|
}
|
|
}
|