plotly png generation using wkhtmltoimage

.travis.yml

@@ -1,21 +1,37 @@
 # Documentation: http://docs.travis-ci.com/user/languages/julia/
 language: julia
-# os:
-#   - linux
-#   - osx
-# julia:
-#   - 0.4
-#   #- nightly
+os:
+  - linux
+  - osx
+julia:
+  - 0.4
+  #- nightly
 
-# borrowed from Blink.jl's travis file
-matrix:
-  include:
-    - os: linux
-      julia: 0.4
-      env: TESTCMD="xvfb-run julia"
-    - os: osx
-      julia: 0.4
-      env: TESTCMD="julia"
+
+addons:
+  apt:
+    packages:
+      - wkhtmltopdf
+
+before install:
+  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew update          ; fi
+  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew install wkhtmltopdf; fi
+
+
+# sudo: required
+# before_install:
+#   - sudo apt-get -qq update
+#   - sudo apt-get install wkhtmltopdf-dbg -y
+
+# # borrowed from Blink.jl's travis file
+# matrix:
+#   include:
+#     - os: linux
+#       julia: 0.4
+#       env: TESTCMD="xvfb-run julia"
+#     - os: osx
+#       julia: 0.4
+#       env: TESTCMD="julia"
 
 notifications:
   email: true
@@ -33,5 +49,7 @@ script:
  - julia -e 'Pkg.clone("https://github.com/spencerlyon2/PlotlyJS.jl.git")'
  # - julia -e 'Pkg.add("Cairo"); Pkg.build("Cairo")'
  - julia -e 'ENV["PYTHON"] = ""; Pkg.add("PyPlot"); Pkg.build("PyPlot")'
- - $TESTCMD -e 'Pkg.test("Plots"; coverage=false)'
+
+ # - $TESTCMD -e 'Pkg.test("Plots"; coverage=false)'
+ - julia -e 'Pkg.test("Plots"; coverage=false)'
  # - julia -e 'cd(Pkg.dir("Plots")); Pkg.add("Coverage"); using Coverage; Coveralls.submit(process_folder()); Codecov.submit(process_folder())'

src/backends/plotly.jl

@@ -215,6 +215,8 @@ end
 function plotly_layout(d::KW)
   d_out = KW()
 
+  d_out[:width], d_out[:height] = d[:size]
+
   bgcolor = webcolor(d[:background_color])
   fgcolor = webcolor(d[:foreground_color])
 
@@ -458,7 +460,7 @@ function html_body(plt::Plot{PlotlyBackend}, style = nothing)
       Plotly.plot(PLOT, $(get_series_json(plt)), $(get_plot_json(plt)));
     </script>
   """
-  @show html
+  # @show html
   html
 end
 
@@ -498,7 +500,7 @@ end
 # ----------------------------------------------------------------
 
 function Base.writemime(io::IO, ::MIME"image/png", plt::AbstractPlot{PlotlyBackend})
-  warn("todo: png")
+    writemime_png_from_html(io, plt)
 end
 
 function Base.writemime(io::IO, ::MIME"text/html", plt::AbstractPlot{PlotlyBackend})

src/backends/plotlyjs.jl

@@ -8,6 +8,7 @@ function _initialize_backend(::PlotlyJSBackend; kw...)
     end
 
     for (mime, fmt) in PlotlyJS._mimeformats
+        # mime == "image/png" && continue  # don't use plotlyjs's writemime for png
         @eval Base.writemime(io::IO, m::MIME{symbol($mime)}, p::Plot{PlotlyJSBackend}) = writemime(io, m, p.o)
     end
 
@@ -113,9 +114,14 @@ end
 
 # ----------------------------------------------------------------
 
-function Base.writemime(io::IO, m::MIME"text/html", plt::AbstractPlot{PlotlyJSBackend})
-    Base.writemime(io, m, plt.o)
-end
+# function Base.writemime(io::IO, m::MIME"text/html", plt::AbstractPlot{PlotlyJSBackend})
+#     Base.writemime(io, m, plt.o)
+# end
+
+# function Base.writemime(io::IO, ::MIME"image/png", plt::AbstractPlot{PlotlyJSBackend})
+#     println("here!")
+#     writemime_png_from_html(io, plt)
+# end
 
 function Base.display(::PlotsDisplay, plt::Plot{PlotlyJSBackend})
     display(plt.o)

src/backends/web.jl

@@ -26,13 +26,35 @@ function open_browser_window(filename::AbstractString)
     warn("Unknown OS... cannot open browser window.")
 end
 
-function standalone_html_window(plt::AbstractPlot; kw...)
-    html = standalone_html(plt; kw...)
-    # println(html)
+function write_temp_html(plt::AbstractPlot)
+    html = standalone_html(plt; title = plt.plotargs[:title])
     filename = string(tempname(), ".html")
     output = open(filename, "w")
     write(output, html)
     close(output)
+    filename
+end
+
+function standalone_html_window(plt::AbstractPlot)
+    filename = write_temp_html(plt)
     open_browser_window(filename)
 end
 
+# uses wkhtmltopdf/wkhtmltoimage: http://wkhtmltopdf.org/downloads.html
+function html_to_png(html_fn, png_fn, w, h)
+    run(`wkhtmltoimage --width $w --height $h --disable-smart-width $html_fn $png_fn`)
+end
+
+function writemime_png_from_html(io::IO, plt::AbstractPlot)
+    # write html to a temporary file
+    html_fn = write_temp_html(plt)
+
+    # convert that html file to a temporary png file using wkhtmltoimage
+    png_fn = tempname() * ".png"
+    w, h = plt.plotargs[:size]
+    html_to_png(html_fn, png_fn, w, h)
+
+    # now read that file data into io
+    pngdata = readall(png_fn)
+    write(io, pngdata)
+end

test/runtests.jl

@@ -33,11 +33,11 @@ facts("GR") do
     # image_comparison_facts(:gr, only=[1], eps=img_eps)
 end
 
-facts("PlotlyJS") do
-    @fact plotlyjs() --> Plots.PlotlyJSBackend()
-    @fact backend() --> Plots.PlotlyJSBackend()
+facts("Plotly") do
+    @fact plotly() --> Plots.PlotlyBackend()
+    @fact backend() --> Plots.PlotlyBackend()
 
-    image_comparison_facts(:plotlyjs, only=[1,2,3,4,7,8,9,10,11,12,14,15,20,22,23,24,27], eps=img_eps)
+    image_comparison_facts(:plotly, only=[1,3,4,7,8,9,10,11,12,14,15,20,22,23,27], eps=img_eps)
 end
 
 FactCheck.exitstatus()