feat: use native interrupt support in Downloads.jl (#82)

Detect if we are using a newer version of Download.jl that supports interrupting of requests natively and use that instead of throwing `InterruptException`.

ref: JuliaLang/Downloads.jl#256 and JuliaLang/Downloads.jl#259

fixes: #81

Project.toml

@@ -4,7 +4,7 @@ keywords = ["Swagger", "OpenAPI", "REST"]
 license = "MIT"
 desc = "OpenAPI server and client helper for Julia"
 authors = ["JuliaHub Inc."]
-version = "0.1.25"
+version = "0.1.26"
 
 [deps]
 Base64 = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"

src/client.jl

@@ -151,6 +151,7 @@ struct Client
  escape_path_params::Union{Nothing,Bool}
  chunk_reader_type::Union{Nothing,Type{<:AbstractChunkReader}}
  long_polling_timeout::Int
+ request_interrupt_supported::Bool
 
  function Client(root::String;
  headers::Dict{String,String}=Dict{String,String}(),
@@ -174,7 +175,8 @@ struct Client
  # disable ALPN to support servers that enable both HTTP/2 and HTTP/1.1 on same port
  Downloads.Curl.setopt(easy, LibCURL.CURLOPT_SSL_ENABLE_ALPN, 0)
  end
- new(root, headers, get_return_type, clntoptions, downloader, Ref{Int}(timeout), pre_request_hook, escape_path_params, chunk_reader_type, long_polling_timeout)
+ interruptable = request_supports_interrupt()
+ new(root, headers, get_return_type, clntoptions, downloader, Ref{Int}(timeout), pre_request_hook, escape_path_params, chunk_reader_type, long_polling_timeout, interruptable)
  end
 end
 
@@ -556,6 +558,10 @@ function do_request(ctx::Ctx, stream::Bool=false; stream_to::Union{Channel,Nothi
 
  try
  if stream
+ interrupt = nothing
+ if ctx.client.request_interrupt_supported
+ kwargs[:interrupt] = interrupt = Base.Event()
+ end
  @sync begin
  download_task = @async begin
  try
@@ -565,7 +571,10 @@ function do_request(ctx::Ctx, stream::Bool=false; stream_to::Union{Channel,Nothi
  kwargs...
  )
  catch ex
- if !isa(ex, InterruptException)
+ # If request method does not support interrupt natively, InterrptException is used to
+ # signal the download task to stop. Otherwise, InterrptException is not handled and is rethrown.
+ # Any exception other than InterruptException is rethrown always.
+ if ctx.client.request_interrupt_supported || !isa(ex, InterruptException)
  @error("exception invoking request", exception=(ex,catch_backtrace()))
  rethrow()
  end
@@ -604,10 +613,25 @@ function do_request(ctx::Ctx, stream::Bool=false; stream_to::Union{Channel,Nothi
  catch ex
  isa(ex, InvalidStateException) || rethrow(ex)
  interrupted = true
- istaskdone(download_task) || schedule(download_task, InterruptException(), error=true)
+ if !istaskdone(download_task)
+ # If the download task is still running, interrupt it.
+ # If it supports interrupt natively, then use event to signal it.
+ # Otherwise, throw an InterruptException to stop the download task.
+ if ctx.client.request_interrupt_supported
+ notify(interrupt)
+ else
+ schedule(download_task, InterruptException(), error=true)
+ end
+ end
+ end
+ end
+ if !interrupted && !istaskdone(download_task)
+ if ctx.client.request_interrupt_supported
+ notify(interrupt)
+ else
+ schedule(download_task, InterruptException(), error=true)
  end
  end
- interrupted || istaskdone(download_task) || schedule(download_task, InterruptException(), error=true)
  end
  end
  else
@@ -863,4 +887,13 @@ function deep_object_serialize(dict::Dict, parent_key::String = "")
  return Dict(parts)
 end
 
+function request_supports_interrupt()
+ for m in methods(request)
+ if :interrupt in Base.kwarg_decl(m)
+ return true
+ end
+ end
+ return false
+end
+
 end # module Clients