Refactor making requests for BwdServer.Tests

fsharp-backend/tests/Tests/BwdServer.Tests.fs

@@ -16,6 +16,7 @@ module RT = LibExecution.RuntimeTypes
 module PT = LibExecution.ProgramTypes
 module Routing = LibBackend.Routing
 module Canvas = LibBackend.Canvas
+module DvalRepr = LibExecution.DvalReprExternal
 
 open TestUtils.TestUtils
 open System.Text.Json
@@ -292,48 +293,10 @@ let t filename =
         return client
       }
 
-    let callServer (server : Server) : Task<unit> =
+    let makeRequest (request : byte array) (port : int) : Task<Http.T> =
       task {
-        let port =
-          match server with
-          | OCaml -> TestConfig.ocamlServerNginxPort
-          | FSharp -> TestConfig.bwdServerBackendPort
-
-        let host = $"{meta.name}.builtwithdark.localhost:{port}"
-        let canvasName = string meta.name
-
-        let request =
-          test.request
-          |> replaceByteStrings "HOST" host
-          |> replaceByteStrings "CANVAS" canvasName
-          |> Http.setHeadersToCRLF
-
-        // Check body matches content-length
-        let incorrectContentTypeAllowed =
-          test.request
-          |> UTF8.ofBytesWithReplacement
-          |> String.includes "ALLOW-INCORRECT-CONTENT-LENGTH"
-
-        if not incorrectContentTypeAllowed then
-          let parsedTestRequest = Http.split request
-          let contentLength =
-            parsedTestRequest.headers
-            |> List.find (fun (k, v) -> String.toLowercase k = "content-length")
-          match contentLength with
-          | None -> ()
-          | Some (_, v) ->
-            if String.includes "ALLOW-INCORRECT-CONTENT-LENGTH" v then
-              ()
-            else
-              Expect.equal parsedTestRequest.body.Length (int v) ""
-
-        // Check input LENGTH not set
-        if test.request |> UTF8.ofBytesWithReplacement |> String.includes "LENGTH"
-           && not incorrectContentTypeAllowed then // false alarm as also have LENGTH in it
-          Expect.isFalse true "LENGTH substitution not done on request"
-
         // Make a request
-        use! client = createClient (port)
+        use! client = createClient port
         use stream = client.GetStream()
         stream.ReadTimeout <- 1000 // responses should be instant, right?
 
@@ -348,8 +311,58 @@ let t filename =
         client.Close()
         let response = Array.take byteCount responseBuffer
 
+        return Http.split response
+      }
+
+    let prepareRequest (host : string) (canvasName : string) : byte array =
+      let request =
+        test.request
+        |> replaceByteStrings "HOST" host
+        |> replaceByteStrings "CANVAS" canvasName
+        |> Http.setHeadersToCRLF
+
+      // Check body matches content-length
+      let incorrectContentTypeAllowed =
+        test.request
+        |> UTF8.ofBytesWithReplacement
+        |> String.includes "ALLOW-INCORRECT-CONTENT-LENGTH"
+
+      if not incorrectContentTypeAllowed then
+        let parsedTestRequest = Http.split request
+        let contentLength =
+          parsedTestRequest.headers
+          |> List.find (fun (k, v) -> String.toLowercase k = "content-length")
+        match contentLength with
+        | None -> ()
+        | Some (_, v) ->
+          if String.includes "ALLOW-INCORRECT-CONTENT-LENGTH" v then
+            ()
+          else
+            Expect.equal parsedTestRequest.body.Length (int v) ""
+
+      // Check input LENGTH not set
+      if test.request |> UTF8.ofBytesWithReplacement |> String.includes "LENGTH"
+         && not incorrectContentTypeAllowed then // false alarm as also have LENGTH in it
+        Expect.isFalse true "LENGTH substitution not done on request"
+
+      request
+
+    let callServer (server : Server) : Task<unit> =
+      task {
+        let port =
+          match server with
+          | OCaml -> TestConfig.ocamlServerNginxPort
+          | FSharp -> TestConfig.bwdServerBackendPort
+
+        let host = $"{meta.name}.builtwithdark.localhost:{port}"
+        print $"{host}"
+        let canvasName = string meta.name
+
+        let request = prepareRequest host canvasName
+        let! actual = makeRequest request port
+
         // Prepare expected response
-        let expectedResponse =
+        let expected =
           test.response
           |> splitAtNewlines
           |> List.filterMap (fun line ->
@@ -378,35 +391,31 @@ let t filename =
           |> replaceByteStrings "HOST" host
           |> replaceByteStrings "CANVAS" canvasName
           |> Http.setHeadersToCRLF
+          |> Http.split
 
         // Parse and normalize the response
-        let actual = Http.split response
-        let expected = Http.split expectedResponse
         let eHeaders = normalizeExpectedHeaders expected.headers actual.body
         let aHeaders = normalizeActualHeaders actual.headers
 
-        // Decompress the body if returned with a content-encoding. Throws an exception if content-encoding is set and the body is not encrypted. This lets us test that the server returns compressed content
+        // Decompress the body if returned with a content-encoding. Throws an
+        // exception if content-encoding is set and the body is not compressed. This
+        // lets us test that the server returns compressed content
         let actual =
           { actual with body = Http.decompressIfNeeded actual.headers actual.body }
 
         // Test as json or strings
         let asJson =
           try
             Some(
-              LibExecution.DvalReprExternal.parseJson (
-                UTF8.ofBytesUnsafe actual.body
-              ),
-              LibExecution.DvalReprExternal.parseJson (
-                UTF8.ofBytesUnsafe expected.body
-              )
+              DvalRepr.parseJson (UTF8.ofBytesUnsafe actual.body),
+              DvalRepr.parseJson (UTF8.ofBytesUnsafe expected.body)
             )
           with
           | e -> None
 
         match asJson with
         | Some (aJson, eJson) ->
-          let serialize (json : JsonDocument) =
-            LibExecution.DvalReprExternal.writePrettyJson json.WriteTo
+          let serialize (json : JsonDocument) = DvalRepr.writePrettyJson json.WriteTo
           Expect.equal
             (actual.status, aHeaders, serialize aJson)
             (expected.status, eHeaders, serialize eJson)