Merge pull request #396 from JuliaPlots/kaleido

migrate kaleido support from PlotlyBase over to PlotlyJS

Project.toml

@@ -4,10 +4,12 @@ authors = ["Spencer Lyon <[email protected]>"]
 version = "0.18.0"
 
 [deps]
+Base64 = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"
 Blink = "ad839575-38b3-5650-b840-f874b8c74a25"
 DelimitedFiles = "8bb1440f-4735-579b-a4ab-409b98df4dab"
 JSExpr = "97c1335a-c9c5-57fe-bc5d-ec35cebe8660"
 JSON = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"
+Kaleido_jll = "f7e6163d-2fa5-5f23-b69c-1db539e41963"
 Markdown = "d6f4376e-aef5-505a-96c1-9c027394607a"
 Pkg = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
 PlotlyBase = "a03496cd-edff-5a9b-9e67-9cda94a718b5"
@@ -20,7 +22,7 @@ WebIO = "0f1e0344-ec1d-5b48-a673-e5cf874b6c29"
 Blink = "0.12"
 JSExpr = "0.5"
 JSON = "0.20, 0.21"
-PlotlyBase = "0.6, 0.7"
+PlotlyBase = "0.6, ^0.7"
 Reexport = "0.2, 1"
 Requires = "1.0"
 WebIO = "0.8"

src/PlotlyJS.jl

@@ -1,5 +1,6 @@
 module PlotlyJS
 
+using Base64
 using Reexport
 @reexport using PlotlyBase
 using JSON
@@ -34,6 +35,7 @@ struct PlotlyJSDisplay <: AbstractDisplay end
 # include the rest of the core parts of the package
 include("display.jl")
 include("util.jl")
+include("kaleido.jl")
 
 make_subplots(;kwargs...) = plot(Layout(Subplots(;kwargs...)))
 
@@ -50,19 +52,6 @@ function docs()
     Blink.content!(w, "html", open(f -> read(f, String), schema_path), fade=false, async=false)
 end
 
-PlotlyBase.savefig(p::SyncPlot, a...; k...) = savefig(p.plot, a...; k...)
-PlotlyBase.savefig(io::IO, p::SyncPlot, a...; k...) = savefig(io, p.plot, a...; k...)
-
-for (mime, fmt) in PlotlyBase._KALEIDO_MIMES
-    @eval function Base.show(
-        io::IO, ::MIME{Symbol($mime)}, plt::SyncPlot,
-        width::Union{Nothing,Int}=nothing,
-        height::Union{Nothing,Int}=nothing,
-        scale::Union{Nothing,Real}=nothing,
-    )
-        savefig(io, plt.plot, format=$fmt)
-    end
-end
 
 @enum RENDERERS BLINK IJULIA BROWSER DOCS
 
@@ -106,6 +95,8 @@ function __init__()
         @warn("Warnings were generated during the last build of PlotlyJS:  please check the build log at $_build_log")
     end
 
+    @async _start_kaleido_process()
+
     if !isfile(_js_path)
         @info("plotly.js javascript libary not found -- downloading now")
         include(joinpath(_pkg_root, "deps", "build.jl"))

src/kaleido.jl

@@ -0,0 +1,219 @@
+using Kaleido_jll
+
+mutable struct Pipes
+    stdin::Pipe
+    stdout::Pipe
+    stderr::Pipe
+    proc::Base.Process
+    Pipes() = new()
+end
+
+const P = Pipes()
+
+const ALL_FORMATS = ["png", "jpeg", "webp", "svg", "pdf", "eps", "json"]
+const TEXT_FORMATS = ["svg", "json", "eps"]
+
+function _restart_kaleido_process()
+    if isdefined(P, :proc) && process_running(P.proc)
+        kill(P.proc)
+    end
+    _start_kaleido_process()
+end
+
+
+function _start_kaleido_process()
+    global P
+    try
+        BIN = let
+            art = Kaleido_jll.artifact_dir
+            cmd = if Sys.islinux() || Sys.isapple()
+                joinpath(art, "kaleido")
+            else
+                # Windows
+                joinpath(art, "kaleido.cmd")
+            end
+            no_sandbox = "--no-sandbox"
+            Sys.isapple() ? `$(cmd) plotly --disable-gpu --single-process` : `$(cmd) plotly --disable-gpu $(no_sandbox)`
+        end
+        kstdin = Pipe()
+        kstdout = Pipe()
+        kstderr = Pipe()
+        kproc = run(pipeline(BIN,
+                             stdin=kstdin, stdout=kstdout, stderr=kstderr),
+                    wait=false)
+        process_running(kproc) || error("There was a problem startink up kaleido.")
+        close(kstdout.in)
+        close(kstderr.in)
+        close(kstdin.out)
+        Base.start_reading(kstderr.out)
+        P.stdin = kstdin
+        P.stdout = kstdout
+        P.stderr = kstderr
+        P.proc = kproc
+
+        # read startup message and check for errors
+        res = readline(P.stdout)
+        if length(res) == 0
+            error("Could not start Kaleido process")
+        end
+
+        js = JSON.parse(res)
+        if get(js, "code", 0) != 0
+            error("Could not start Kaleido process")
+        end
+    catch e
+        @warn "Kaleido is not available on this system. Julia will be unable to save images of any plots."
+        @warn "$e"
+    end
+    nothing
+end
+
+function savefig(
+        p::Plot;
+        width::Union{Nothing,Int}=nothing,
+        height::Union{Nothing,Int}=nothing,
+        scale::Union{Nothing,Real}=nothing,
+        format::String="png"
+    )::Vector{UInt8}
+    if !(format in ALL_FORMATS)
+        error("Unknown format $format. Expected one of $ALL_FORMATS")
+    end
+
+    # construct payload
+    _get(x, def) = x === nothing ? def : x
+    payload = Dict(
+        :width => _get(width, 700),
+        :height => _get(height, 500),
+        :scale => _get(scale, 1),
+        :format => format,
+        :data => p
+    )
+
+    _ensure_kaleido_running()
+
+    # convert payload to vector of bytes
+    bytes = transcode(UInt8, JSON.json(payload))
+    write(P.stdin, bytes)
+    write(P.stdin, transcode(UInt8, "\n"))
+    flush(P.stdin)
+
+    # read stdout and parse to json
+    res = readline(P.stdout)
+    js = JSON.parse(res)
+
+    # check error code
+    code = get(js, "code", 0)
+    if code != 0
+        msg = get(js, "message", nothing)
+        error("Transform failed with error code $code: $msg")
+    end
+
+    # get raw image
+    img = String(js["result"])
+
+    # base64 decode if needed, otherwise transcode to vector of byte
+    if format in TEXT_FORMATS
+        return transcode(UInt8, img)
+    else
+        return base64decode(img)
+    end
+end
+
+"""
+    savefig(
+        io::IO,
+        p::Plot;
+        width::Union{Nothing,Int}=nothing,
+        height::Union{Nothing,Int}=nothing,
+        scale::Union{Nothing,Real}=nothing,
+        format::String="png"
+    )
+
+Save a plot `p` to the io stream `io`. They keyword argument `format`
+determines the type of data written to the figure and must be one of
+$(join(ALL_FORMATS, ", ")), or html. `scale` sets the
+image scale. `width` and `height` set the dimensions, in pixels. Defaults
+are taken from `p.layout`, or supplied by plotly
+"""
+function savefig(io::IO,
+        p::Plot;
+        width::Union{Nothing,Int}=nothing,
+        height::Union{Nothing,Int}=nothing,
+        scale::Union{Nothing,Real}=nothing,
+        format::String="png")
+
+
+    if format == "html"
+        return show(io, MIME("text/html"), p, include_mathjax="cdn", include_plotlyjs="cdn", full_html=true)
+    end
+
+    bytes = savefig(p, width=width, height=height, scale=scale, format=format)
+    write(io, bytes)
+end
+
+"""
+    savefig(
+        p::Plot, fn::AbstractString;
+        format::Union{Nothing,String}=nothing,
+        width::Union{Nothing,Int}=nothing,
+        height::Union{Nothing,Int}=nothing,
+        scale::Union{Nothing,Real}=nothing,
+    )
+
+Save a plot `p` to a file named `fn`. If `format` is given and is one of
+$(join(ALL_FORMATS, ", ")), or html; it will be the format of the file. By
+default the format is guessed from the extension of `fn`. `scale` sets the
+image scale. `width` and `height` set the dimensions, in pixels. Defaults
+are taken from `p.layout`, or supplied by plotly
+"""
+function savefig(
+        p::Plot, fn::AbstractString;
+        format::Union{Nothing,String}=nothing,
+        width::Union{Nothing,Int}=nothing,
+        height::Union{Nothing,Int}=nothing,
+        scale::Union{Nothing,Real}=nothing,
+    )
+    ext = split(fn, ".")[end]
+    if format === nothing
+        format = String(ext)
+    end
+
+    open(fn, "w") do f
+        savefig(f, p; format=format, scale=scale, width=width, height=height)
+    end
+    return fn
+end
+
+_kaleido_running() = isdefined(P, :stdin) && isopen(P.stdin) && process_running(P.proc)
+_ensure_kaleido_running() = !_kaleido_running() && _restart_kaleido_process()
+
+const _KALEIDO_MIMES = Dict(
+    "application/pdf" => "pdf",
+    "image/png" => "png",
+    "image/svg+xml" => "svg",
+    "image/eps" => "eps",
+    "image/jpeg" => "jpeg",
+    "image/jpeg" => "jpeg",
+    "application/json" => "json",
+    "application/json; charset=UTF-8" => "json",
+)
+
+for (mime, fmt) in _KALEIDO_MIMES
+    @eval function Base.show(
+        io::IO, ::MIME{Symbol($mime)}, plt::Plot,
+        width::Union{Nothing,Int}=nothing,
+        height::Union{Nothing,Int}=nothing,
+        scale::Union{Nothing,Real}=nothing,
+    )
+        savefig(io, plt, format=$fmt)
+    end
+
+    @eval function Base.show(
+        io::IO, ::MIME{Symbol($mime)}, plt::SyncPlot,
+        width::Union{Nothing,Int}=nothing,
+        height::Union{Nothing,Int}=nothing,
+        scale::Union{Nothing,Real}=nothing,
+    )
+        savefig(io, plt.plot, format=$fmt)
+    end
+end

test/kaleido.jl

@@ -0,0 +1,17 @@
+function myplot(fn)
+    x = 0:0.1:2π
+    plt = Plot(scatter(x=x, y=sin.(x)))
+    savefig(plt, fn)
+end
+
+@testset "kaleido" begin
+    for ext in [PlotlyBase.ALL_FORMATS..., "html"]
+        if ext === "eps"
+            continue
+        end
+        @show fn = tempname() * "." * ext
+        myplot(fn) == fn
+        @test isfile(fn)
+        rm(fn)
+    end
+end

test/runtests.jl

@@ -8,5 +8,6 @@ using Blink
 !Blink.AtomShell.isinstalled() && Blink.AtomShell.install()
 
 include("blink.jl")
+include("kaleido.jl")
 
 end