GraphViz
A Swift package for working with GraphViz.
Requirements
- Swift 5.1+
- GraphViz (only for rendering)
Usage
import GraphViz
var graph = Graph(directed: true)
let a = Node("a"), b = Node("b"), c = Node("c")
graph.append(Edge(from: a, to: b))
graph.append(Edge(from: a, to: c))
var b_c = Edge(from: b, to: c)
b_c.constraint = false
graph.append(b_c)
// Produce DOT language representation
let dot = DOTEncoder().encode(graph)
// Render image using dot layout algorithm
let data = try! graph.render(using: .dot, to: .svg)
let svg = String(data: data, encoding: .utf8)!
digraph {
a -> b
a -> c
b -> c [constraint=false]
}Note: The
render(using:to:)method requires that the GraphViz binary corresponding to the specified layout algorithm is accessible from the current$PATH.
Using Function Builders, Custom Operators, and Fluent Attribute Setters
To use the following interface,
add "GraphVizBuilder" to your package's dependencies
and replace import GraphViz with import GraphVizBuilder as needed.
import GraphVizBuilder
let graph = Graph(directed: true) {
"a" --> "b"
"a" --> "c"
("b" --> "c").constraint(false)
}Note: Swift 5.1 may require explicit typecast expressions in order to reconcile use of custom edge operators like
-->. (error: ambiguous reference to member '-->')
Installation
Swift Package Manager
Add the GraphViz package to your target dependencies in Package.swift:
import PackageDescription
let package = Package(
name: "YourProject",
dependencies: [
.package(
url: "https://github.com/SwiftDocOrg/GraphViz",
from: "0.1.3"
),
]
)Add GraphViz as a dependency to your target(s):
targets: [
.target(
name: "YourTarget",
dependencies: ["GraphViz"]),To render graphs to SVG, PNG, and other formats,
you must have GraphViz executables (e.g. dot) installed on your system
and accessible from $PATH.
You can install GraphViz from the command line:
# macOS
$ brew install graphviz
# Linux (Ubuntu)
$ sudo apt-get install graphviz
License
MIT
Contact
Mattt (@mattt)