Parses the Graphviz DOT language in golang

So, the attributes is now a static set (found in common/attributes.go). The API still takes a map[string]string but all public methods (AddNode, AddAttr etc) will call FromStringMap(), which will create a Attrs from the string map, and then pass them into private methods (addNode, addAttr, etc)

This way, the API stays the same, per #4 .

Caveat: I have also silenced the panic(err) in almost all of them because the test cases themselves are wrong/have wrong attributes. I'll probably leave that to someone else to fix. (grep for the below:)

if err != nil {
    // panic(err)  // TODO: Fix...
}```

From https://blog.golang.org/using-go-modules:

Each different major version (v1, v2, and so on) of a Go module uses a different module path: starting at v2, the path must end in the major version. In the example, v3 of rsc.io/quote is no longer rsc.io/quote: instead, it is identified by the module path rsc.io/quote/v3. This convention is called semantic import versioning

Currently running go mod download in a module using github.com/awalterschulze/gographviz in version v2.0.2 results in the following error:

github.com/awalterschulze/[email protected]+incompatible: invalid version: +incompatible suffix not allowed: module contains a go.mod file, so semantic import versioning is required

This pull request contains backwards incompatible changes:

1. Some methods now return errors, instead of panicing.
2. Attributes are checked to be valid attributes.

I want to edit a node attributes inside a graph. Is there any way to get the node by name of node and edit it? Like in nodejs package JNXnetwork we can do that by

G.node.get(0).foo = 'bar';

Is there anyway in this package to do that?

Thanks

Given an input graph with default node/edge attributes and a subgraph, like this one:

digraph g {
    node [shape=record];
    edge [style=dashed];
    subgraph cluster_key {
        graph [label=KEY];
        key_user [fontcolor=red];
        key_dep  [fontcolor=blue];
        key_user -> key_dep;
    }
    A [fontcolor=red];
    B [fontcolor=blue];
    A -> B;
}

In the rendering from dot, the default attributes are inherited by the objects in the subgraph:

but gographviz only applies the attributes to the top-level objects, not the ones in the subgraph:

it's not allowed use like this:

graph.AddAttr(workflowName, "node", "shape=rect style=rounded, labelloc=b")

but if set attribute one by one, it will not take affect.

graph.AddAttr(workflowName, "shape", "rect")
graph.AddAttr(workflowName, "style", "rounded")
graph.AddAttr(workflowName, "labelloc", "b")

What I am trying to achive:

Code I used:

g := gographviz.NewGraph()
g.SetName("G")
g.SetDir(true)

g.AddNode("G", "Ga", nil)
g.AddNode("G", "Gb", nil)
g.AddEdge("Ga", "Gb", true, nil)

g.AddSubGraph("G", "clusterone", map[string]string{
    "style": "filled", 
    "fillcolor": "red",
})
g.AddNode("clusterone", "sA", nil)
g.AddNode("clusterone", "sB", nil)
g.AddEdge("sA", "sB", true, nil)

g.AddSubGraph("clusterone", "clustertwo", map[string]string{
    "style": "filled", 
    "fillcolor": "blue",
})
g.AddNode("clustertwo", "ssA", nil)
g.AddNode("clustertwo", "ssB", nil)
g.AddEdge("ssA", "ssB", true, nil)

fmt.Println(g.String())

However this is what the result looked like:

Am I doing something wrong?

Hi there, thanks for this package.

My node IDs and attribute values disagree strongly with the DOT schema, and I've found that I have to quote them in order for tools like Gephi to parse them as they all are of type "ID".

Could gographviz detect the need to quote/escape anything that it needs to write out as type ID and do so automatically so I don't have to add the quotes myself? Here's an example that produces an unreadable file:

graph := gographviz.NewGraph()
graph.SetName("G")
graph.AddNode("G", "331fb1985e8884cfaaae65be7f8cfe5b", gographviz.Attrs{"label": "1:6:1w/w/PYqH7d1+6Fg"})
graph.AddEdge("331fb1985e8884cfaaae65be7f8cfe5b", "ec2f3d34a4f4c4f82dd1d0b2f1a581e", gographviz.Attrs{"label": "FOO_BAR"})
os.Stdout.Write(gographviz.WriteAst().String())

Thanks!

Hi,

first of all, many thanks for the great library - it's really a pleasure to use!

I am currently evaluating gographviz for another project (https://github.com/bbernhard/imagemonkey-core) and would be glad if I could use it there.

One thing I am currently struggling with is, the possibility to extract a subtree based on a given label. If I understood the documentation correctly, then that's what SortedChildren is meant to be for. However, for some obscure reason it doesn't seem to work - it looks like I have messed something up here.

Here is a small code snippet which illustrates my problem. truck, bike, motorbike and car are all children of vehicle. When asking gographviz for the label vehicle I would like to get a list of all its children. I tried to accomplish that with graph.Relations.SortedChildren("vehicle") but that returns an empty list.

I am pretty sure that I have missed something here and would be glad, if you could point me in the right direction.

Thanks a lot, Bernhard

package main

import (
	"bytes"
	"os"
	"fmt"
	"github.com/awalterschulze/gographviz"
)

func main() {
	graphAst, _ := gographviz.ParseString(`
		digraph G { 
			{ 
				car [label="car" id="94bbd2ff-8a8e-4d1c-9ac5-f9506aa20e43"] 
				vehicle [color=green style=filled label="vehicle"] 
				truck [label="truck"] 
			} 
			
		   vehicle -> truck
		    vehicle -> car
		    vehicle -> motorbike
		    vehicle -> bike
		}
	`)
	graph := gographviz.NewGraph()
	graph.SetDir(true)
	if err := gographviz.Analyse(graphAst, graph); err != nil {
    	panic(err)
	}

	childrens := graph.Relations.SortedChildren("vehicle")
	for _, child := range childrens {
		fmt.Printf("%s\n", child)
	}
}

There's an issue where making edges between cluster subgraphs (which are useful with fdp) would double subgraphs in output string.

Consider this code:

g := gographviz.NewEscape()
g.SetName("G")
g.SetDir(false)
g.AddSubGraph("G", "cluster0", map[string]string{"label": "root"})
g.AddSubGraph("cluster0", "cluster_1", map[string]string{"label": "child 1"})
g.AddSubGraph("cluster0", "cluster_2", map[string]string{"label": "child 2"})
nodeStyle := map[string]string{"style": "rounded"}
g.AddNode("cluster_1", "1", nodeStyle)
g.AddNode("cluster_1", "2", nodeStyle)
g.AddNode("cluster_2", "3", nodeStyle)
g.AddNode("cluster_2", "4", nodeStyle)
g.AddNode("G", "Code deployment", map[string]string{"style": "dotted"})
g.AddPortEdge("cluster_2", "", "cluster_1", "", false, nil)
s := g.String()
fmt.Println(s)

It currently renders such code, which is incorrect and would not render:

graph G { subgraph cluster_2 { label="child 2"; 3 [ style=rounded ]; 4 [ style=rounded ];

} --subgraph cluster_1 { label="child 1"; 1 [ style=rounded ]; 2 [ style=rounded ];

}; subgraph cluster0 { label=root; subgraph cluster_1 { label="child 1"; 1 [ style=rounded ]; 2 [ style=rounded ];

} ; subgraph cluster_2 { label="child 2"; 3 [ style=rounded ]; 4 [ style=rounded ];

} ;

} ; "Code deployment" [ style=dotted ];

}

After the patch applied it would make such code (subgraphs starting with cluster would be rendered as nodes for edges): graph G { cluster_2--cluster_1; subgraph cluster0 { label=root; subgraph cluster_1 { label="child 1"; 1 [ style=rounded ]; 2 [ style=rounded ];

} ; subgraph cluster_2 { label="child 2"; 3 [ style=rounded ]; 4 [ style=rounded ];

} ;

} ; "Code deployment" [ style=dotted ];

}

Created github action that performs the same tasks as travis job.

Note that the badge in Readme.md is already pointing to https://github.com/awalterschulze/gographviz to work correctly when merged.

I am using the following to update node labels in an Escape

graph.Nodes.Lookup[id].Attrs.Extend(attrs)

but the new label is not automatically escaped. Maybe there is a better way to update node attributes that I'm missing.

On the other hand, if this is a bug, I'd happy to try to fix it. At a first glance at the implementation, it does not look like the escaping logic is executed for any Attrs method.

Thanks!

Hi, all.

I am trying to use the node, edge, and graph statement from the Lexical and Semantic Notes. However, since this library always sorts and prints nodes, the order is changed. How can I always define it first?

Output:

digraph G {
	rank=LR;
	Hello->World[ headlabel="head", taillabel="tail" ];
	Hello->World:f0;
	Hello->World:f1;
	Hello->World:f2;
	Hello [ label="Hi\nStart", shape=Mrecord ];
	World [ label="<f0>one|<f1>two|<f2>three", shape=Mrecord ];
	node [ shape=Mrecord ];
}

You can see that the node line is defined last.

Expected:

digraph G {
	node [ shape=Mrecord ];  <-------------- This line
	rank=LR;
	Hello->World[ headlabel="head", taillabel="tail" ];
	Hello->World:f0;
	Hello->World:f1;
	Hello->World:f2;
	Hello [ label="Hi\nStart", shape=Mrecord ];
	World [ label="<f0>one|<f1>two|<f2>three", shape=Mrecord ];
}

Only when defined like this, the output I want is completed.

Looking at the source code, there seem to be no solutions. For now, is the only way to add properties to each node?

...
go 1.14

require github.com/awalterschulze/gographviz v2.0.1+incompatible
...

From the spec http://www.graphviz.org/content/dot-language

As another aid for readability, dot allows double-quoted strings to span
multiple physical lines using the standard C convention of a backslash
immediately preceding a newline character.

In addition, double-quoted strings can be concatenated using a '+' operator.

isNumber in escape.go is supposed to return true if it is passed a string that represents a number. However, it accepts "127.0.0.1" as a number but dot does not accept that. More generally it allows an arbitrary number of "."s in a number. This causes strings to not be escaped when they should be.