unable to render graph in shiny

[edanisabird]

I have really been loving DiagrammeR so far. I was able to get a fully functioning diagram built in rstudio. It is of the format:

Graph Code:
nodes <- create_nodes()
edges <- create_edges()
graph <- create_graph(nodes_df = nodes, edges_df = edges)
render_graph(graph)

However when I try to run it in my shiny app using something like

UI:
DiagrammeROutput("mindmap", width = "100%", height = "400px")

Server:
output$mindmap <- renderDiagrammeR({Graph code from above})

I get an error:
parse error with digraph { #my graph code} undefined is not an object (evaluating 'w[0]')
This is the error I get no matter how simple i make the graph and when i try using grViz, DiagrammeR() and several other options. Is there a working example or documentation or help I can get here on how to set up the code so that I get even a simple graph showing in Shiny.

Thank you so much for the help,

Edan

[rich-iannone]

Sorry for the delay on this but I do have two examples now. Both of these do generate the graphs in Shiny (v. 0.12.1).

Using standard Graphviz DOT code to create a graph in Shiny:

library(DiagrammeR)

diagram <- "
digraph {

      # graph attributes
      graph [overlap = true]

      # node attributes
      node [shape = box,
      fontname = Helvetica,
      color = blue]

      # edge attributes
      edge [color = gray]

      # node statements
      A; B; C; D; E
      F [color = black]

      # node attributes
      node [shape = circle,
      fixedsize = true,
      width = 0.9]

      # node statements
      1; 2; 3; 4; 5; 6; 7; 8

      # edge statements
      A->1; B->2                   // gray
      B->3 [color = red]           // red
      B->4                         // gray
      C->A [color = green]         // green
      1->D; E->A; 2->4; 1->5; 1->F // gray
      E->6; 4->6; 5->7; 6->7       // gray
      3->8 [color = blue]          // blue
      }
"

# Shiny app
server <- function(input, output) {
  output$diagram <- renderGrViz({
    grViz({
      diagram
    })
  })
}

ui <- fluidPage(
  grVizOutput('diagram', width = "100%", height = "760px") 
)

shinyApp(ui = ui, server = server)

Using graph functions to first generate a graph object; passing the DOT code (inside the graph object) to Shiny.

library(DiagrammeR)

# Create a node data frame
nodes <-
  create_nodes(nodes = c("a", "b", "c", "d"),
               label = FALSE,
               type = "lower",
               style = "filled",
               color = "aqua",
               shape = c("circle", "circle",
                         "rectangle", "rectangle"),
               data = c(3.5, 2.6, 9.4, 2.7))

edges <-
  create_edges(from = c("a", "b", "c"),
               to = c("d", "c", "a"),
               relationship = "leading_to")


graph <-
  create_graph(nodes_df = nodes,
               edges_df = edges,
               node_attrs = "fontname = Helvetica",
               edge_attrs = c("color = blue",
                              "arrowsize = 2"))

# Shiny app
server <- function(input, output) {
  output$diagram <- renderGrViz({
    grViz({
      graph$dot_code
    })
  })
}

ui <- fluidPage(
  grVizOutput('diagram', width = "100%", height = "760px") 
)

shinyApp(ui = ui, server = server)

[edanisabird]

Thank you so much for the help! I was able to get my code working and now I am starting to style the app to have interactive mind maps in shiny.

[rich-iannone]

Not a problem at all! I'll think I'll post these examples because, you're right, there's no available documentation on this.

[edanisabird]

I have no idea how difficult it is to put them in the CRAN documentation. But that would be the most helpful for users in the future! Thanks again.

[manalirupji]

Can we incorporate mermaid functionality of the DiagrammeR package with shinyR?