PAaSO/apps/shinyDAG-1.0.0/R/module/dagPreview.R

288 lines
8 KiB
R

# UI Function -------------------------------------------------------------
dagPreviewUI <- function(id, include_graph_downloads = TRUE, start_hidden = FALSE) {
ns <- shiny::NS(id)
class_3_col <- "col-md-4 col-md-offset-0 col-sm-8 col-sm-offset-2 col-xs-12"
download_choices <- c(
"PDF" = "pdf",
"PNG" = "png",
"LaTeX TikZ" = "tikz"
)
if (include_graph_downloads) {
download_choices <- c(
download_choices,
"dagitty (R: RDS)" = "dag_dagitty",
"ggdag (R: RDS)" = "dag_tidy"
)
}
tagList(
fluidRow(
column(
width = 12,
align = "center",
shinyjs::hidden(tags$div(
id = ns("tikzOut-help"),
class="alert alert-danger",
role="alert",
HTML(
"<p>An error occurred while compiling the preview.",
"Are there syntax errors in your labels?</p>",
"<p>Note that using characters that are",
'<a href="https://en.wikibooks.org/wiki/LaTeX/Special_Characters" target="_blank">reserved',
'characters in LaTeX</a> syntax may cause issues. For example,',
"single <code>$</code> need to be escaped: <code>\\$</code>.</p>"
)
)),
tags$div(
class = "dag-preview-tikz",
shinycssloaders::withSpinner(uiOutput(ns("tikzOut")), color = "#C4C4C4", proxy.height = "400px")
)
)
),
fluidRow(
tags$div(
class = class_3_col,
tags$div(
id = ns("showPreviewContainer"),
prettySwitch(ns("showPreview"), "Preview DAG", status = "primary", fill = TRUE, value = !start_hidden)
)
),
tags$div(
class = class_3_col,
selectInput(
inputId = ns("downloadType"),
label = "Type of download",
choices = download_choices
),
uiOutput(ns("downloadType_helptext"))
),
tags$div(
class = paste(class_3_col, "dagpreview-download-ui"),
div(
class = "btn-group",
role = "group",
id = ns("download-buttons"),
downloadButton(ns("downloadButton"))
)
)
)
)
}
# Server Module -----------------------------------------------------------
# This module takes tikz code and creates DAG preview content and returns TRUE
# or FALSE value to track whether the preview is visible.
dagPreview <- function(
input, output, session,
session_dir,
tikz_code,
dag_dagitty = reactive(NULL),
dag_tidy = reactive(NULL),
has_edges = reactive(FALSE)
) {
ns <- session$ns
SESSION_TEMPDIR <- file.path(session_dir, sub("-$", "", ns("")))
tikz_cache_dir <- reactiveVal(NULL)
# Render tikz preview ----
observe({
req(input$showPreview)
tikz_lines <- tikz_code()
req(gsub("\\s", "", tikz_lines) != "")
debug_input(tikz_lines, ns("tikz_code"))
useLib <- "\\usetikzlibrary{matrix,arrows,decorations.pathmorphing}"
pkgs <- paste(buildUsepackage(pkg = list("tikz"), uselibrary = useLib), collapse = "\n")
tex_dir <-
tex_cached_preview(
session_dir = SESSION_TEMPDIR,
obj = tikz_lines,
stem = "DAGimage",
imgFormat = "png",
returnType = "shiny",
density = tex_opts$get("density"),
keep_pdf = TRUE,
usrPackages = pkgs,
margin = tex_opts$get("margin"),
cleanup = tex_opts$get("cleanup")
)
tikz_cache_dir(tex_dir)
}, priority = -100)
# Create tikz preview UI ----
output$tikzOut <- renderUI({
req(input$showPreview)
shiny::validate(
shiny::need(
tryCatch({tikz_code(); TRUE}, error = function(e) FALSE) ||
tryCatch(gsub("\\s", "", tikz_code()), error = function(e) "") != "",
paste(
"Nothing to see here... yet. Please use the Sketch tab to create",
"and layout a DAG."
)
)
)
if (is.null(tikz_cache_dir())) return()
if (!length(tikz_cache_dir())) {
shinyjs::show("tikzOut-help")
return()
} else {
shinyjs::hide("tikzOut-help")
}
image_path <- file.path(tikz_cache_dir(), "DAGimage.png")
if (!file.exists(image_path)) {
debug_line("Image does not exist: ", image_path)
return()
}
image_tmp <- tempfile("dag_image_", SESSION_TEMPDIR, ".png")
file.copy(image_path, image_tmp)
debug_line("Serving image: ", image_tmp)
tags$img(
src = sub("www/", "", image_tmp, fixed = TRUE),
contentType = "image/png",
style = "max-width: 100%; max-height: 600px; -o-object-fit: contain;",
alt = "DAG"
)
})
output$downloadType_helptext <- renderUI({
is_tikz_download <- input$downloadType %in% c("pdf", "png", "tikz")
if (is_tikz_download && !input$showPreview) {
shinyjs::disable("downloadButton")
return(helpText("Please preview DAG to enable downloads"))
}
if (!is_tikz_download && !has_edges()) {
shinyjs::disable("downloadButton")
return(helpText("Please add at least one edge to the DAG"))
}
if (!length(tikz_cache_dir())) {
shinyjs::disable("downloadButton")
return()
}
shinyjs::enable("downloadButton")
})
output$downloadButton <- downloadHandler(
filename = function() {
paste0(
"DAG.",
switch(
input$downloadType,
"dagitty" =,
"ggdag" = "rds",
"tikz" = "tex",
"png" = "png",
"pdf" = "pdf"
)
)
},
content = function(file) {
if (input$downloadType == "pdf") {
file.copy(file.path(tikz_cache_dir(), "DAGimageDoc.pdf"), file)
} else if (input$downloadType == "png") {
file.copy(file.path(tikz_cache_dir(), "DAGimage.png"), file)
} else if (input$downloadType == "tikz") {
merge_tex_files(
file.path(tikz_cache_dir(), "DAGimageDoc.tex"),
file.path(tikz_cache_dir(), "DAGimage.tex"),
file
)
} else if (input$downloadType == "dag_dagitty") {
if (is.null(dag_dagitty())) return(NULL)
saveRDS(dag_dagitty(), file = file)
} else if (input$downloadType == "dag_tidy") {
if (is.null(dag_tidy())) return(NULL)
saveRDS(dag_tidy(), file = file)
}
},
contentType = NA
)
return(reactive(input$showPreview))
}
# Helper Functions --------------------------------------------------------
tex_cached_preview <- function(session_dir, ...) {
# Takes arguments for texPreview() except for fileDir
# hashes inputs and then writes preview into session_dir/args_hash
# Skips rendering if the cache already exists
# Returns directory containing the preview documents
args <- list(...)
args_hash <- digest::digest(args)
session_token <- basename(dirname(session_dir))
error_file <- paste0(session_token, "_", args_hash, ".tex")
cache_dir <- file.path(session_dir, args_hash)
error_dir <- file.path("www", "errors")
if (dir.exists(cache_dir)) {
return(cache_dir)
} else {
if (file.exists(file.path(error_dir, error_file))) {
# we already know that this tikz code won't work
warning("Bad tikz is still bad: ", error_file)
return(character())
}
}
dir.create(cache_dir, recursive = TRUE)
args$fileDir <- cache_dir
tryCatch({
do.call("texPreview", args)
cache_dir
}, error = function(e) {
# write bad tex code to disk
dir.create(error_dir, showWarnings = FALSE)
cat(
args$obj,
sep = "\n",
file = file.path(error_dir, error_file)
)
unlink(cache_dir, recursive = TRUE)
character()
})
}
# Merge tikz TeX source into main TeX file
merge_tex_files <- function(main_file, input_file, out_file) {
x <- readLines(main_file)
y <- readLines(input_file)
which_line <- grep("input{", x, fixed = TRUE)
which_line <- intersect(which_line, grep(basename(input_file), x))
x[which_line] <- paste(y, collapse = "\n")
writeLines(x, out_file)
}