Inserting hyperlinks into node labels in DiagrammeR - r

Question

I would like to be able to create flowcharts with DiagrammeR in R so that I can export SVG through the devtools::install_github('rich-iannone/DiagrammeRsvg') package.
My flowcharts must include hyperlinks in some of the nodes, unfortunately I can't find an acceptable way to create node labels with functioning <a> tags. Here are the different methods I've tried:
Mermaid
Using DiagrammeR(diagram = "", type = "mermaid") it's possible to use HTML tags in the node labels:
library("DiagrammeR")
DiagrammeR("graph TB;
A{Is your data public?} -- yes -->C;
A -- no -->B[<center><b>Oxshef: dataviz</b> only supports researchers <br> in the creation of interactive data visualisations that public</center>];
C{<center>Please make it public?</center>};
D[<center>Supported!</center>];
E[<center>Unsupported!</center>];
F[Refer to our tutorial];
C -- yes -->D;
C -- no -->E;
C -- I don't know -->F")
But to use the <a> tag we need to use an = which the parser vomits over:
DiagrammeR("graph TB;
A{Is your data public?} -- yes -->C;
A -- no -->B[<center><b>Oxshef: dataviz</b> only supports researchers <br> in the creation of interactive data visualisations that public</center>];
C{<center>Please make it public?</center>};
D[<center>Supported!</center>];
E[<center>Unsupported!</center>];
F[Refer to our <a href='http://google.com'>tutorial</a>];
C -- yes -->D;
C -- no -->E;
C -- I don't know -->F")
grViz
Here's the same flowchart as above but with all html stripped out and converted to grViz:
grViz("
digraph boxes_and_circles {
# a 'graph' statement
graph [overlap = true, fontsize = 10]
# several 'node' statements
node [shape = box,
fontname = Helvetica]
A [label = 'Is your data public?']; B [label = 'Please make it public'];
C [label = 'Tech Question']; D [label = 'Supported' ];
E [label = 'Unsupported!']; F [label = 'Refer to our tutorial']
# several 'edge' statements
A->B A->C C->D [label = 'yes'] C->E [label = 'no'] C->F [label = 'Unknown']
}
")
This doesn't support HTML tags:
grViz("
digraph boxes_and_circles {
# a 'graph' statement
graph [overlap = true, fontsize = 10]
# several 'node' statements
node [shape = box,
fontname = Helvetica]
A [label = 'Is your data public?']; B [label = '<b>Please</b> make it public'];
C [label = 'Tech Question']; D [label = 'Supported' ];
E [label = 'Unsupported!']; F [label = 'Refer to our tutorial']
# several 'edge' statements
A->B A->C C->D [label = 'yes'] C->E [label = 'no'] C->F [label = 'Unknown']
}
")
create_graph
DiagrammeR also lets us create graph as follows:
ndf_no_tags <- create_node_df(n = 6,
label = c("Is your data public?",
"Please make it public",
"Tech Question",
"Supported",
"Unsupported",
"Refer to our tutorial"))
# Create an edge data frame (edf)
edf <- create_edge_df(from = c(1, 1, 3, 3, 3),
to = c(2, 3, 4, 5, 6))
ndf_no_tags %>%
create_graph(edges_df = edf) %>%
render_graph()
But it escapes HTML tags:
ndf_with_tags <- create_node_df(n = 6,
label = c("Is your data public?",
"<b>Please</b> make it public",
"Tech Question",
"Supported",
"Unsupported",
"Refer to our tutorial"))
ndf_with_tags %>%
create_graph(edges_df = edf) %>%
render_graph()

Answer 1

I figured it out for the mermaid function:
mermaid('
graph LR
A-->B
A-->C
C-->E
B-->D
C-->D
D-->F
E-->F
click B "http://www.github.com" "This is a link"
')
the click B <link> option requires double quotes, and thankfully R accepts single quotes for the entire mermaid code block.