chore: prefer http.jl backend with openapi (#65)

The recent version of OpenAPI.jl added ability to switch the HTTP library between Downloads.jl and HTTP.jl. With Kuber.jl we prefer HTTP.jl as it might help avoid certain concurrency issues observed earlier.

Author: tanmaykm

Project.toml

@@ -4,7 +4,7 @@ authors = ["JuliaHub Inc."]
 keywords = ["kubernetes", "client"]
 license = "MIT"
 desc = "Julia Kubernetes Client"
-version = "0.7.7"
+version = "0.7.8"
 
 [deps]
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"

src/helpers.jl

@@ -38,6 +38,39 @@ Backoff to use when retrying k8s APIs. The default minimum is 2 TPS.
 """
 k8s_retry(f; max_tries=1, tps=2) = retry(f, delays=k8s_delay(tps,max_tries), check=k8s_retry_cond)()
 
+"""
+Build keyword arguments for OpenAPI.Clients.Client constructor.
+Detects if HTTP.jl backend is available (OpenAPI >= 0.2.1) and uses it by default.
+
+Args:
+- httplib: Optional HTTP library to use (:http or :downloads). Defaults to HTTP.jl if available.
+"""
+function _openapi_client_kwargs(httplib::Union{Nothing,Symbol}=nothing)
+    kwargs = Dict{Symbol,Any}()
+    if isdefined(OpenAPI.Clients, :HTTPLib)
+        if httplib === nothing
+            kwargs[:httplib] = OpenAPI.Clients.HTTPLib.HTTP  # Default to HTTP.jl
+        else
+            kwargs[:httplib] = httplib
+        end
+    end
+    return kwargs
+end
+
+"""
+Return appropriate Connection header value based on HTTP backend.
+
+Args:
+- httplib: Optional HTTP library being used (:http or :downloads). Defaults to HTTP.jl logic.
+"""
+function _connection_header_value(httplib::Union{Nothing,Symbol}=nothing)
+    if !isdefined(OpenAPI.Clients, :HTTPLib)
+        return "close"
+    end
+    effective_lib = httplib === nothing ? OpenAPI.Clients.HTTPLib.HTTP : httplib
+    return effective_lib === OpenAPI.Clients.HTTPLib.HTTP ? "Keep-Alive" : "close"
+end
+
 const KuberEventStream = Channel{Any}
 
 struct KApi
@@ -54,13 +87,15 @@ mutable struct KuberContext
     default_retries::Int
     retry_all_apis::Bool
     initialized::Bool
+    httplib::Union{Nothing,Symbol}
 
-    function KuberContext(apimodule::Module=ApiImpl; kwargs...)
+    function KuberContext(apimodule::Module=ApiImpl; httplib::Union{Nothing,Symbol}=nothing, kwargs...)
         kctx = new(apimodule)
 
         rtfn = (return_types,response_code,response_data)->kuber_type(kctx, return_types, response_code, response_data)
-        openapiclient = OpenAPI.Clients.Client(DEFAULT_URI; get_return_type=rtfn, kwargs...)
-        openapiclient.headers["Connection"] = "close"
+        client_kwargs = _openapi_client_kwargs(httplib)
+        openapiclient = OpenAPI.Clients.Client(DEFAULT_URI; get_return_type=rtfn, client_kwargs..., kwargs...)
+        openapiclient.headers["Connection"] = _connection_header_value(httplib)
 
         kctx.client = openapiclient
         kctx.apis = Dict{Symbol,Vector}()
@@ -69,6 +104,7 @@ mutable struct KuberContext
         kctx.default_retries = 5
         kctx.retry_all_apis = false
         kctx.initialized = false
+        kctx.httplib = httplib
         return kctx
     end
 end
@@ -90,10 +126,10 @@ end
 
 function KuberException(response::OpenAPI.Clients.ApiResponse, status::Union{Nothing,OpenAPI.APIModel})
     http_response = response.raw
-    if !(200 <= http_response.status <= 299)
-        message = http_response.message
-        code = http_response.status
-    end
+    code = http_response.status
+
+    # HTTP.Response doesn't have .message field like Downloads.Response
+    message = hasproperty(http_response, :message) ? http_response.message : "HTTP $code"
 
     # if status is available, use it to override the message and code
     if !isnothing(status)
@@ -212,7 +248,7 @@ get_server(ctx::KuberContext) = ctx.client.root
 get_ns(ctx::KuberContext) = ctx.namespace
 
 """
-    set_server(ctx, uri, reset_api_versions=false; max_tries=5, kwargs...)
+    set_server(ctx, uri, reset_api_versions=false; max_tries=5, httplib=nothing, kwargs...)
 
 Set the Kubernetes API server endpoint for a context.
 
@@ -224,6 +260,7 @@ Args:
 Keyword Args:
 - max_tries: retries allowed while probing API versions from server
 - verbose: Log API versions
+- httplib: HTTP library to use (:http or :downloads). If not specified, uses the context's stored httplib setting.
 - kwargs: other keyword args to pass on while constructing the client for API server (see OpenAPI.jl - https://github.com/JuliaComputing/OpenAPI.jl#readme)
 """
 function set_server(
@@ -233,11 +270,22 @@ function set_server(
     max_tries=retries(ctx, false),
     verbose::Bool=false,
     debug::Bool=false,
+    httplib::Union{Nothing,Symbol}=nothing,
     kwargs...
 )
+    # Use provided httplib, or fall back to context's stored value
+    effective_httplib = httplib === nothing ? ctx.httplib : httplib
+
     rtfn = (return_types,response_code,response_data)->kuber_type(ctx, return_types, response_code, response_data)
-    ctx.client = OpenAPI.Clients.Client(uri; get_return_type=rtfn, verbose=debug, kwargs...)
-    ctx.client.headers["Connection"] = "close"
+    client_kwargs = _openapi_client_kwargs(effective_httplib)
+    ctx.client = OpenAPI.Clients.Client(uri; get_return_type=rtfn, verbose=debug, client_kwargs..., kwargs...)
+    ctx.client.headers["Connection"] = _connection_header_value(effective_httplib)
+
+    # Update stored httplib if explicitly provided
+    if httplib !== nothing
+        ctx.httplib = httplib
+    end
+
     reset_api_versions && set_api_versions!(
         ctx;
         max_tries=max_tries,

test/runtests.jl

@@ -21,6 +21,11 @@ function init_context(override=nothing, verbose=true)
     set_ns(ctx, "default")
     set_retries(ctx; count=3, all_apis=false)
     Kuber.set_api_versions!(ctx; override=override, verbose=verbose)
+    httplib_name = ctx.httplib === nothing ? "http (default)" : string(ctx.httplib)
+    @info("KuberContext preferred HTTP library: $httplib_name")
+    if hasproperty(ctx.client, :httplib)
+        @info("OpenAPI client using HTTP library: $(ctx.client.httplib)")
+    end
     ctx
 end