From 410995ce4dfa2fc955582abd00d65640af03f63f Mon Sep 17 00:00:00 2001
From: Willem van Verseveld <willem.vanverseveld@gmail.com>
Date: Tue, 3 Dec 2024 11:49:29 +0100
Subject: [PATCH 1/3] Wflow server: allow JSON reading and writing of `NaN` and
 `Inf` By setting `allow_inf` arg to `true`.

---
 server/src/server.jl  | 4 ++--
 server/test/client.jl | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/server/src/server.jl b/server/src/server.jl
index b3aded4be..33cae0d33 100644
--- a/server/src/server.jl
+++ b/server/src/server.jl
@@ -89,7 +89,7 @@ function wflow_bmi(s::ZMQ.Socket, handler::ModelHandler, f)
             response(s)
         else
             @info "Send response including output from Wflow function `$(f.fn)`"
-            ZMQ.send(s, JSON3.write(ret))
+            ZMQ.send(s, JSON3.write(ret; allow_inf = true))
         end
     catch e
         @error "Wflow function `$(f.fn)` failed" exception = (e, catch_backtrace())
@@ -151,7 +151,7 @@ function start(port::Int)
         while true
             # Wait for next request from client
             req = ZMQ.recv(socket)
-            json = JSON3.read(req)
+            json = JSON3.read(req; allow_inf = true)
             @info "Received request to run function `$(json.fn)`..."
 
             if haskey(map_structs, json.fn)
diff --git a/server/test/client.jl b/server/test/client.jl
index 1688af26f..06921cde2 100644
--- a/server/test/client.jl
+++ b/server/test/client.jl
@@ -10,7 +10,7 @@ ZMQ.connect(socket, "tcp://localhost:5555")
 
 function request(message)
     ZMQ.send(socket, JSON3.write(message))
-    ret_value = JSON3.read(ZMQ.recv(socket), Dict)
+    ret_value = JSON3.read(ZMQ.recv(socket), Dict; allow_inf = true)
     return ret_value
 end
 

From 43e43822d47dfd53cbf8f8af0a03084297d51073 Mon Sep 17 00:00:00 2001
From: Willem van Verseveld <willem.vanverseveld@gmail.com>
Date: Tue, 3 Dec 2024 12:28:11 +0100
Subject: [PATCH 2/3] Add small server test To test if `NaN` values are
 allowed.

---
 server/test/client.jl | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/server/test/client.jl b/server/test/client.jl
index 06921cde2..009a37a19 100644
--- a/server/test/client.jl
+++ b/server/test/client.jl
@@ -24,6 +24,12 @@ end
     @test request((fn = "get_time_units",)) == Dict("time_units" => "s")
 end
 
+@testset "Reading and writing NaN values allowed" begin
+    msg =
+        (fn = "get_value", name = "vertical.soil.variables.vwc[1]", dest = fill(0.0, 50063))
+    @test isnan(mean(request(msg)["value"]))
+end
+
 @testset "update functions" begin
     @test request((fn = "update_until", time = 86400.0)) == Dict("status" => "OK")
     @test request((fn = "get_current_time",)) == Dict("current_time" => 86400)

From f860bbcf90b4639f90d0cd6bef7124e592bb01a8 Mon Sep 17 00:00:00 2001
From: Willem van Verseveld <willem.vanverseveld@gmail.com>
Date: Tue, 3 Dec 2024 12:43:46 +0100
Subject: [PATCH 3/3] Update changelog

---
 docs/changelog.qmd | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/docs/changelog.qmd b/docs/changelog.qmd
index c5ad6760f..ac5903765 100644
--- a/docs/changelog.qmd
+++ b/docs/changelog.qmd
@@ -16,6 +16,9 @@ project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 - Mutating BMI model control functions (`update`, `update_until` and `finalize`) and
   extended mutating BMI functions (`load_state` and `save_state`) should return `nothing`.
 - Added downloading of testdata to Dockerfile, to ensure an image was able to build.
+- Wflow ZMQ server: allow JSON reading and writing of `NaN` and `Inf` values to avoid a JSON
+  spec error. For example, during initialization of a wflow model, some (diagnostic) model
+  variables are initialized with `NaN` values.
 
 ### Changed
 - Removed vertical concepts `HBV` and `FLEXTopo`.