Convert IJulia provider to extension

Author: halleysfifthinc

Project.toml

@@ -19,9 +19,16 @@ UUIDs = "cf7118a7-6976-5b1a-9a39-7adc72f591a4"
 WebSockets = "104b5d7c-a370-577a-8038-80a2059c5097"
 Widgets = "cc8bc4a8-27d6-5769-a93b-9d913e69aa62"
 
+[weakdeps]
+IJulia = "7073ff75-c697-5162-941a-fcdaad2a7d2a"
+
+[extensions]
+IJuliaExt = "IJulia"
+
 [compat]
 AssetRegistry = "0.1.0"
 FunctionalCollections = "0.5.0"
+IJulia = "1.13"
 JSON = "0.18, 0.19, 0.20, 0.21"
 Observables = "0.5"
 Requires = "0.4.4, 0.5, 1.0.0"

ext/ijulia.jl renamed to ext/IJuliaExt.jl

@@ -1,16 +1,19 @@
-using .AssetRegistry
-using .Sockets
-using .WebIO
+module IJuliaExt
 
-struct IJuliaConnection <: AbstractConnection
-    comm::IJulia.CommManager.Comm
-end
+using WebIO
+using WebIO: WEBIO_NODE_MIME, _IJuliaInit
+using IJulia, Sockets
+
+# struct IJuliaConnection <: AbstractConnection
+#     comm::IJulia.CommManager.Comm
+# end
+IJuliaConnection = Connection{IJulia.CommManager.Comm}
 
 function Sockets.send(c::IJuliaConnection, data)
-    IJulia.send_comm(c.comm, data)
+    IJulia.send_comm(connection(c), data)
 end
 
-Base.isopen(c::IJuliaConnection) = haskey(IJulia.CommManager.comms, c.comm.id)
+Base.isopen(c::IJuliaConnection) = haskey(IJulia.CommManager.comms, connection(c).id)
 
 WebIO.register_renderable(T::Type, ::Val{:ijulia}) = nothing
 
@@ -37,7 +40,6 @@ installed for `WEBIO_NODE_MIME` that is preferred over `text/html`. If the HTML
 content is actually displayed, it means that the WebIO integration is not
 correctly installed.
 """
-struct _IJuliaInit end
 
 function Base.show(io::IO, m::WEBIO_NODE_MIME, ::_IJuliaInit)
     Base.show(io, m, node(:div))
@@ -68,16 +70,18 @@ function main()
         return
     end
 
-    # https://github.com/JuliaLang/IJulia.jl/pull/755
-    if isdefined(IJulia, :register_jsonmime)
-        IJulia.register_jsonmime(WEBIO_NODE_MIME())
-    else
-        @warn "IJulia doesn't have register_mime; WebIO may not work as expected. Please upgrade to IJulia v1.13.0 or greater."
-    end
+    IJulia.register_jsonmime(WEBIO_NODE_MIME())
 
     # See comment on _IJuliaInit for what this does
     display(_IJuliaInit())
+
+    return nothing
 end
 
 WebIO.setup_provider(::Val{:ijulia}) = main() # calling setup_provider(Val(:ijulia)) will display the setup javascript
-WebIO.setup(:ijulia)
+
+function __init__()
+    WebIO.setup(:ijulia)
+end
+
+end

src/WebIO.jl

@@ -95,17 +95,24 @@ function prefetch_provider_file(basename)
 end
 
 provider_mux = prefetch_provider_file("mux.jl")
-provider_ijulia = prefetch_provider_file("ijulia.jl")
 provider_generic_http = prefetch_provider_file("generic_http.jl")
 
+struct _IJuliaInit
+    function _IJuliaInit()
+        # based on assert_extension from longemen3000/ExtensionsExt
+        ext = Base.get_extension(@__MODULE__, :IJuliaExt)
+        if isnothing(ext)
+            throw(error("Extension `IJuliaExt` must be loaded to construct internal type `_IJuliaInit`."))
+        end
+        return new()
+    end
+end
+
 function __init__()
     push!(Observables.addhandler_callbacks, WebIO.setup_comm)
     @require Mux="a975b10e-0019-58db-a62f-e48ff68538c9" begin
         include_string(@__MODULE__, provider_mux.code, provider_mux.file)
     end
-    @require IJulia="7073ff75-c697-5162-941a-fcdaad2a7d2a" begin
-        include_string(@__MODULE__, provider_ijulia.code, provider_ijulia.file)
-    end
     @require WebSockets="104b5d7c-a370-577a-8038-80a2059c5097" begin
         include_string(@__MODULE__, provider_generic_http.code, provider_generic_http.file)
     end

src/connection.jl

@@ -1,9 +1,16 @@
 using Sockets
 
-export AbstractConnection
+export AbstractConnection, Connection, connection
 
 abstract type AbstractConnection end
 
+struct Connection{C} <: AbstractConnection
+    conn::C
+end
+
+function connection end
+connection(c::Connection) = c.conn
+
 """
 The maximum number of messages to allow into the outbox.
 """