d2a1d2f · rowtype-yoga/purescript-yoga-fetch-om

git.iko.soy/rowtype-yoga/purescript-yoga-fetch-om

Add ParseResponseBody/BodyEncoding, fix 304 handling, bump to 0.6.3

- ParseResponse: add ParseResponseBody typeclass (String bypasses readJSON, ReadForeign fallback); route all non-2xx through parseErrorRL (fixes 304 Not Modified test) - ParseResponse: add Unit instance for bodyless error responses - MakeRequest: add BodyEncoding typeclass keyed on encoding type (JSON, FormData, NoBody) rather than body type, carrying both content-type and serialisation - ExtractParams: add ExtractBodyEncoding to thread encoding type through the client 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

commitd2a1d2fdcede82a66a9b1383502943c92dc56f67 authorMark Eibes <mark.eibes@wolt.com> dateThu 21 May 2026, 15:28 (4 months ago) parentea69984

11 files changed+300−34

compare with main

unifiedsplit

package.json+3−1 spago.yaml+1−1 src/Yoga/Fetch/Om.purs+6−5 src/Yoga/Fetch/Om/ExtractParams.purs+13 src/Yoga/Fetch/Om/MakeRequest.js+1 src/Yoga/Fetch/Om/MakeRequest.purs+27−19 src/Yoga/Fetch/Om/ParseResponse.purs+30−7 src/Yoga/Fetch/Om/SplitResponses.purs+13−1 test/BodylessResponse.Example.purs+27 test/BodylessResponse.Spec.purs+98 test/PlainTextResponse.Spec.purs+81

package.json+3−1

@@ -30,5 +30,7 @@

3030 "spago": "0.93.42",

3131 "vitest": "^2.1.8"

3232 },

33− "dependencies": {}

33+ "dependencies": {

34+ "pino": "^10.3.1"

35+ }

3436}

spago.yaml+1−1

@@ -2,7 +2,7 @@ workspace: {}

22package:

33 name: yoga-fetch-om

44 publish:

5− version: 0.6.2

5+ version: 0.6.3

66 license: MIT

77 location:

88 githubOwner: rowtype-yoga

src/Yoga/Fetch/Om.purs+6−5

@@ -34,8 +34,8 @@ import Yoga.Fetch.Om.BuildUrl (class BuildUrl, buildUrl)

3434import Yoga.Fetch.Om.Simple (class DecodeResponse, decodeResponse, FetchError, FetchResponse, get, getWithHeaders, delete, deleteWithHeaders, delete_, post, postWithHeaders, post_, put, putWithHeaders, put_, patch, patchWithHeaders, patch_)

3535import Yoga.Fetch.Om.StreamDecode (class StreamDecode, decodeStream)

3636import Yoga.Fetch.Om.ClientFunction (class BuildClientFn, class CheckBodyIsUnit, buildClientFn)

37−import Yoga.Fetch.Om.ExtractParams (class ExtractRequestBody, class ExtractRequestHeaders)

38−import Yoga.Fetch.Om.MakeRequest (class MakeRequest, class SerializeBody, class ContentType, makeRequest, serializeBody, contentType)

37+import Yoga.Fetch.Om.ExtractParams (class ExtractRequestBody, class ExtractBodyEncoding, class ExtractRequestHeaders)

38+import Yoga.Fetch.Om.MakeRequest (class MakeRequest, class BodyEncoding, makeRequest, encodingContentType, encodeBody)

3939import Yoga.Fetch.Om.ParseResponse (class ParseResponse, parseResponse)

4040import Yoga.Fetch.Om.SplitResponses (class SplitResponses)

4141import Yoga.Fetch.Om.Variant (class VariantOrValue, variantOrValue)

@@ -70,12 +70,12 @@ instance

7070 ( SegmentPathParams segments pathParams

7171 , SegmentQueryParams segments queryParams

7272 , ExtractRequestBody request body

73+ , ExtractBodyEncoding request encoding

7374 , ExtractRequestHeaders request headers

7475 , PathPattern segments

7576 , BuildUrl segments pathParams queryParams

7677 , MakeRequest method

77− , SerializeBody body

78− , ContentType body

78+ , BodyEncoding encoding body

7979 , SplitResponses response successRow routeErrors

8080 , ParseResponse routeErrors successRow

8181 , RowToList successRow successRL

@@ -96,7 +96,8 @@ instance

9696 impl pathQueryRec headersRec bodyVal = do

9797 let url = buildUrl baseUrl (Proxy :: _ segments) pathParamsRec queryParamsRec

9898 let hdrs = toHeaders (Proxy :: _ headersRL) headersRec

99− fetchResp <- makeRequest (Proxy :: _ method) url hdrs (contentType (Proxy :: _ body)) (serializeBody bodyVal) # toOm

99+ let ct = encodingContentType (Proxy :: _ encoding)

100+ fetchResp <- makeRequest (Proxy :: _ method) url hdrs ct (encodeBody @encoding bodyVal) # toOm

100101 variant <- parseResponse fetchResp :: Om (Record ()) routeErrors (Variant successRow)

101102 variantOrValue (Proxy :: _ successRL) variant # pure

102103 where

src/Yoga/Fetch/Om/ExtractParams.purs+13

@@ -1,6 +1,7 @@

11module Yoga.Fetch.Om.ExtractParams

22 ( class ExtractRequestHeaders

33 , class ExtractRequestBody

4+ , class ExtractBodyEncoding

45 , class FindBodyType

56 , class UnwrapEncoding

67 , class FindHeaders

@@ -25,6 +26,18 @@ else instance

2526 ExtractRequestBody (Record row) body =>

2627 ExtractRequestBody (Request (Record row)) body

2728

29+class ExtractBodyEncoding :: Type -> Type -> Constraint

30+class ExtractBodyEncoding request encoding | request -> encoding

31+

32+instance

33+ ( RowToList row rl

34+ , FindBodyType rl encoding

35+ ) =>

36+ ExtractBodyEncoding (Record row) encoding

37+else instance

38+ ExtractBodyEncoding (Record row) encoding =>

39+ ExtractBodyEncoding (Request (Record row)) encoding

40+

2841class ExtractRequestHeaders :: Type -> Row Type -> Constraint

2942class ExtractRequestHeaders request headers | request -> headers

3043

src/Yoga/Fetch/Om/MakeRequest.jsnew file+1

@@ -0,0 +1 @@

1+export const toUrlEncoded = (obj) => new URLSearchParams(obj).toString();

src/Yoga/Fetch/Om/MakeRequest.purs+27−19

@@ -4,8 +4,9 @@ module Yoga.Fetch.Om.MakeRequest

44 , makeRequest

55 , class SerializeBody

66 , serializeBody

7− , class ContentType

8− , contentType

7+ , class BodyEncoding

8+ , encodingContentType

9+ , encodeBody

910 ) where

1011

1112import Prelude

@@ -31,7 +32,8 @@ import JS.Fetch.Integrity (Integrity(..))

3132import JS.Fetch.Duplex as Duplex

3233import JS.Fetch.Response (Response) as FetchResponse

3334import Promise.Aff as Promise

34−import Type.Proxy (Proxy)

35+import Type.Proxy (Proxy(..))

36+import Yoga.HTTP.API.Route.Encoding (JSON, FormData, NoBody)

3537import Yoga.HTTP.API.Route.Method as Method

3638import Yoga.JSON (class WriteForeign, writeJSON)

3739

@@ -63,7 +65,7 @@ makeRequest

6365 -> String

6466 -> Maybe String

6567 -> Aff FetchResponse.Response

66−makeRequest proxy url customHeaders defaultContentType maybeBody = do

68+makeRequest proxy url customHeaders bodyContentType maybeBody = do

6769 request <- Request.new url options # liftEffect

6870 Promise.toAffE $ Fetch.fetch request

6971 where

@@ -73,7 +75,7 @@ makeRequest proxy url customHeaders defaultContentType maybeBody = do

7375 contentTypeArr = case maybeBody of

7476 Nothing -> []

7577 Just _ | hasContentType -> []

76− Just _ -> [ "Content-Type" /\ defaultContentType ]

78+ Just _ -> [ "Content-Type" /\ bodyContentType ]

7779 allHeaders = Headers.fromFoldable (contentTypeArr <> customArr)

7880 body = case maybeBody of

7981 Nothing -> Body.empty

@@ -91,24 +93,30 @@ makeRequest proxy url customHeaders defaultContentType maybeBody = do

9193 , cache: Cache.Default

9294 }

9395

94−class ContentType :: Type -> Constraint

95−class ContentType body where

96− contentType :: Proxy body -> String

97−

98−instance ContentType String where

99− contentType _ = "text/plain"

100−else instance ContentType Unit where

101− contentType _ = "application/json"

102−else instance ContentType body where

103− contentType _ = "application/json"

104−

10596class SerializeBody :: Type -> Constraint

10697class SerializeBody body where

10798 serializeBody :: body -> Maybe String

10899

109−instance SerializeBody String where

110− serializeBody s = Just s

111−else instance SerializeBody Unit where

100+instance SerializeBody Unit where

112101 serializeBody _ = Nothing

113102else instance WriteForeign body => SerializeBody body where

114103 serializeBody b = Just (writeJSON b)

104+

105+class BodyEncoding :: Type -> Type -> Constraint

106+class BodyEncoding encoding body | encoding -> body where

107+ encodingContentType :: Proxy encoding -> String

108+ encodeBody :: body -> Maybe String

109+

110+instance WriteForeign ty => BodyEncoding (JSON ty) ty where

111+ encodingContentType _ = "application/json"

112+ encodeBody b = Just (writeJSON b)

113+

114+else instance BodyEncoding (FormData ty) ty where

115+ encodingContentType _ = "application/x-www-form-urlencoded"

116+ encodeBody b = Just (toUrlEncoded b)

117+

118+else instance BodyEncoding NoBody Unit where

119+ encodingContentType _ = ""

120+ encodeBody _ = Nothing

121+

122+foreign import toUrlEncoded :: forall a. a -> String

src/Yoga/Fetch/Om/ParseResponse.purs+30−7

@@ -5,6 +5,8 @@ module Yoga.Fetch.Om.ParseResponse

55 , parseSuccessRL

66 , class ParseErrorRL

77 , parseErrorRL

8+ , class ParseResponseBody

9+ , parseResponseBody

810 ) where

911

1012import Prelude

@@ -36,6 +38,15 @@ import Yoga.Om.Error (Exception)

3638import Yoga.Om.Strom (Strom)

3739import Yoga.Om.Strom.WebStream as WebStream

3840

41+class ParseResponseBody (body :: Type) where

42+ parseResponseBody :: String -> Either String body

43+

44+instance ParseResponseBody String where

45+ parseResponseBody = Right

46+

47+else instance ReadForeign body => ParseResponseBody body where

48+ parseResponseBody = withStringErrors <<< readJSON

49+

3950class ParseResponse (errorRow :: Row Type) (successRow :: Row Type) where

4051 parseResponse :: FetchResponse.Response -> Om {} errorRow (Variant successRow)

4152

@@ -50,11 +61,9 @@ instance

5061 let status = Fetch.status fetchResp

5162 if status >= 200 && status < 300 then

5263 parseSuccessRL (Proxy :: _ successRL) status fetchResp # toOm

53− else if status >= 400 then do

64+ else do

5465 errorText <- Promise.toAffE (Fetch.text fetchResp) # toOm

5566 parseErrorRL (Proxy :: _ errorRL) (Proxy :: _ errorRow) status errorText

56− else

57− throwError (Variant.inj (Proxy :: _ "exception") (Exception.error ("Unexpected HTTP status code: " <> show status)))

5867

5968class ParseSuccessRL (rl :: RowList Type) (successRow :: Row Type) | rl -> successRow where

6069 parseSuccessRL :: Proxy rl -> Int -> FetchResponse.Response -> Aff (Variant successRow)

@@ -100,7 +109,7 @@ else instance

100109else instance

101110 ( IsSymbol label

102111 , StatusCodeMap label

103− , ReadForeign body

112+ , ParseResponseBody body

104113 , Row.Cons label body tailRow successRow

105114 , Row.Lacks label tailRow

106115 , ParseSuccessRL tailRL successRow

@@ -110,7 +119,7 @@ else instance

110119 let StatusCode expected = statusCodeFor (Proxy :: _ label)

111120 if actualStatus == expected then do

112121 jsonText <- liftEffect (Fetch.text fetchResp) >>= Promise.toAff

113− case withStringErrors (readJSON jsonText) of

122+ case parseResponseBody jsonText of

114123 Left errs -> Aff.throwError (Exception.error ("Failed to parse response (status " <> show actualStatus <> "):\n" <> errs))

115124 Right parsed -> pure (Variant.inj (Proxy :: _ label) parsed)

116125 else

@@ -148,7 +157,21 @@ else instance

148157else instance

149158 ( IsSymbol label

150159 , StatusCodeMap label

151− , ReadForeign body

160+ , Row.Cons label Unit tailRow errorRow

161+ , Row.Lacks label tailRow

162+ , Row.Cons label Unit tailExc (Exception errorRow)

163+ , ParseErrorRL tailRL errorRow

164+ ) =>

165+ ParseErrorRL (RL.Cons label Unit tailRL) errorRow where

166+ parseErrorRL _ errorProxy actualStatus jsonText = do

167+ let StatusCode expected = statusCodeFor (Proxy :: _ label)

168+ if actualStatus == expected then throwError (Variant.inj (Proxy :: _ label) unit)

169+ else parseErrorRL (Proxy :: _ tailRL) errorProxy actualStatus jsonText

170+

171+else instance

172+ ( IsSymbol label

173+ , StatusCodeMap label

174+ , ParseResponseBody body

152175 , Row.Cons label body tailRow errorRow

153176 , Row.Lacks label tailRow

154177 , Row.Cons label body tailExc (Exception errorRow)

@@ -157,7 +180,7 @@ else instance

157180 ParseErrorRL (RL.Cons label body tailRL) errorRow where

158181 parseErrorRL _ errorProxy actualStatus jsonText = do

159182 let StatusCode expected = statusCodeFor (Proxy :: _ label)

160− if actualStatus == expected then case withStringErrors (readJSON jsonText) of

183+ if actualStatus == expected then case parseResponseBody jsonText of

161184 Left errs -> throwError (Variant.inj (Proxy :: _ "exception") (Exception.error ("Failed to parse error response (status " <> show actualStatus <> "):\n" <> errs)))

162185 Right parsed -> throwError (Variant.inj (Proxy :: _ label) parsed)

163186 else

src/Yoga/Fetch/Om/SplitResponses.purs+13−1

@@ -1,5 +1,6 @@

11module Yoga.Fetch.Om.SplitResponses

22 ( class IsSuccessStatus

3+ , class ExtractBodyRL

34 , class ExtractBody

45 , class SplitResponses

56 , class SplitResponsesRL

@@ -10,6 +11,7 @@ import Prim.Boolean (True, False)

1011import Prim.Row as Row

1112import Prim.RowList (RowList)

1213import Prim.RowList as RL

14+import Data.Unit (Unit)

1315import Yoga.HTTP.API.Route (Response)

1416

1517class IsSuccessStatus (label :: Symbol) (isSuccess :: Boolean) | label -> isSuccess

@@ -26,12 +28,22 @@ else instance IsSuccessStatus "alreadyReported" True

2628else instance IsSuccessStatus "imUsed" True

2729else instance IsSuccessStatus label False

2830

31+-- Traverse a RowList to find the "body" field; fall back to Unit if absent.

32+class ExtractBodyRL (rl :: RowList Type) (body :: Type) | rl -> body

33+

34+instance ExtractBodyRL RL.Nil Unit

35+

36+instance ExtractBodyRL (RL.Cons "body" body tail) body

37+

38+else instance ExtractBodyRL tail body => ExtractBodyRL (RL.Cons label ty tail) body

39+

2940class ExtractBody (responseType :: Type) (bodyType :: Type) | responseType -> bodyType

3041

3142instance ExtractBody (Response headers body) body

3243

3344else instance

34− ( Row.Cons "body" body rest row

45+ ( RL.RowToList row rl

46+ , ExtractBodyRL rl body

3547 ) =>

3648 ExtractBody (Record row) body

3749

test/BodylessResponse.Example.pursnew file+27

@@ -0,0 +1,27 @@

1+-- Compile-time test: bodyless responses (e.g. 304, 401) can use {} without

2+-- wrapping in { body :: {} }.

3+module BodylessResponse.Example where

5+import Prelude

7+import Yoga.Fetch.Om (GET, Route, type (/), client)

8+import Yoga.Om (Om)

10+type Resource = { id :: Int, name :: String }

11+

12+type ResourceAPI =

13+ { getResource ::

14+ Route GET

15+ ("resources" / "id")

16+ {}

17+ ( ok :: { body :: Resource }

18+ , notModified :: {}

19+ , unauthorized :: {}

20+ )

21+ }

22+

23+-- This must typecheck: the derived client exposes notModified/unauthorized as Unit errors.

24+api

25+ :: forall ctx err

26+ . { getResource :: Om ctx (notModified :: Unit, unauthorized :: Unit | err) Resource }

27+api = client @ResourceAPI "https://api.example.com"

test/BodylessResponse.Spec.pursnew file+98

@@ -0,0 +1,98 @@

1+module BodylessResponse.Spec where

3+import Prelude

5+import Effect.Ref (Ref)

6+import Effect.Ref as Ref

7+import Effect.Aff (Aff, bracket)

8+import Effect.Aff.Class (liftAff)

9+import Effect.Class (liftEffect)

10+import Foreign (unsafeToForeign)

11+import Test.Spec (Spec, around, describe, it)

12+import Test.Spec.Assertions (shouldEqual)

13+import Yoga.Fastify.Fastify as F

14+import Yoga.Fastify.Fastify (Port(..), Host(..), RouteURL(..), StatusCode(..))

15+import Yoga.Fastify.Om (createOmFastify, getOm)

16+import Yoga.Fetch.Om (GET, Route, type (/), client)

17+import Yoga.Om (Om, runOm)

18+

19+type Resource = { id :: Int, name :: String }

20+

21+type ResourceAPI =

22+ { getResource ::

23+ Route GET

24+ ("bodyless-test" / "resource")

25+ {}

26+ ( ok :: { body :: Resource }

27+ , notModified :: {}

28+ , unauthorized :: {}

29+ )

30+ }

31+

32+api :: forall ctx err. { getResource :: Om ctx (notModified :: Unit, unauthorized :: Unit | err) Resource }

33+api = client @ResourceAPI "http://localhost:44932"

34+

35+spec :: Spec Unit

36+spec = around withServer $ describe "bodyless responses (notModified / unauthorized)" do

37+ it "304 Not Modified triggers the notModified handler" \serverMode -> do

38+ liftEffect $ Ref.write "notModified" serverMode

39+ triggered <- liftEffect $ Ref.new false

40+ runOm {}

41+ { exception: \_ -> pure unit

42+ , notModified: \_ -> liftEffect $ Ref.write true triggered

43+ , unauthorized: \_ -> pure unit

44+ }

45+ (void api.getResource)

46+ result <- liftEffect $ Ref.read triggered

47+ liftAff $ result `shouldEqual` true

48+

49+ it "401 Unauthorized triggers the unauthorized handler" \serverMode -> do

50+ liftEffect $ Ref.write "unauthorized" serverMode

51+ triggered <- liftEffect $ Ref.new false

52+ runOm {}

53+ { exception: \_ -> pure unit

54+ , notModified: \_ -> pure unit

55+ , unauthorized: \_ -> liftEffect $ Ref.write true triggered

56+ }

57+ (void api.getResource)

58+ result <- liftEffect $ Ref.read triggered

59+ liftAff $ result `shouldEqual` true

60+

61+ it "200 OK returns the resource body" \serverMode -> do

62+ liftEffect $ Ref.write "ok" serverMode

63+ resource <- runOm {}

64+ { exception: \_ -> pure { id: -1, name: "" }

65+ , notModified: \_ -> pure { id: -1, name: "" }

66+ , unauthorized: \_ -> pure { id: -1, name: "" }

67+ }

68+ api.getResource

69+ liftAff $ resource `shouldEqual` { id: 1, name: "test" }

70+

71+withServer :: forall a. (Ref String -> Aff a) -> Aff a

72+withServer test = bracket acquire release (\{ serverMode } -> test serverMode)

73+ where

74+ acquire = do

75+ serverMode <- liftEffect $ Ref.new "ok"

76+ fastify <- liftEffect do

77+ f <- F.fastify {}

78+ omApp <- createOmFastify {} f

79+ getOm (RouteURL "/bodyless-test/resource") (handler serverMode) omApp

80+ pure f

81+ void $ F.listen { port: Port 44932, host: Host "0.0.0.0" } fastify

82+ pure { fastify, serverMode }

83+

84+ release { fastify } = F.close fastify

85+

86+ handler serverMode reply = do

87+ mode <- liftEffect $ Ref.read serverMode

88+ case mode of

89+ "notModified" -> do

90+ void $ F.status (StatusCode 304) reply # liftEffect

91+ F.send (unsafeToForeign "") reply # liftAff

92+ "unauthorized" -> do

93+ void $ F.status (StatusCode 401) reply # liftEffect

94+ F.send (unsafeToForeign "") reply # liftAff

95+ _ -> do

96+ void $ F.status (StatusCode 200) reply # liftEffect

97+ void $ F.header "content-type" "application/json" reply # liftEffect

98+ F.sendJson (unsafeToForeign { id: 1, name: "test" }) reply # liftAff

test/PlainTextResponse.Spec.pursnew file+81

@@ -0,0 +1,81 @@

1+module PlainTextResponse.Spec where

3+import Prelude

5+import Effect.Aff (Aff, bracket)

6+import Effect.Aff.Class (liftAff)

7+import Effect.Class (liftEffect)

8+import Effect.Ref (Ref)

9+import Effect.Ref as Ref

10+import Foreign (unsafeToForeign)

11+import Test.Spec (Spec, around, describe, it)

12+import Test.Spec.Assertions (shouldEqual)

13+import Yoga.Fastify.Fastify as F

14+import Yoga.Fastify.Fastify (Port(..), Host(..), RouteURL(..), StatusCode(..))

15+import Yoga.Fastify.Om (createOmFastify, postOm)

16+import Yoga.Fetch.Om (POST, Route, type (/), JSON, client)

17+import Yoga.Om (Om, runOm)

18+

19+type Payload = { value :: Int }

20+type Result = { doubled :: Int }

21+

22+type TestAPI =

23+ { double ::

24+ Route POST

25+ ("plain-text-test" / "double")

26+ { body :: JSON Payload }

27+ ( ok :: { body :: Result }

28+ , badRequest :: { body :: String }

29+ )

30+ }

31+

32+api :: { double :: forall ctx err. Payload -> Om ctx (badRequest :: String | err) Result }

33+api = client @TestAPI "http://localhost:44933"

34+

35+spec :: Spec Unit

36+spec = around withServer $ describe "String body on error responses" do

37+ it "200 OK decodes the JSON response body" \_ -> do

38+ result <- runOm {}

39+ { exception: \_ -> pure { doubled: -1 }

40+ , badRequest: \_ -> pure { doubled: -1 }

41+ }

42+ (api.double { value: 21 })

43+ liftAff $ result `shouldEqual` { doubled: 42 }

44+

45+ it "400 badRequest delivers the raw text body as a String" \serverMode -> do

46+ liftEffect $ Ref.write "badRequest" serverMode

47+ captured <- liftEffect $ Ref.new ""

48+ runOm {}

49+ { exception: \_ -> pure unit

50+ , badRequest: \b -> liftEffect $ Ref.write b captured

51+ }

52+ (void $ api.double { value: 0 })

53+ body <- liftEffect $ Ref.read captured

54+ liftAff $ body `shouldEqual` "invalid value"

55+

56+withServer :: forall a. (Ref String -> Aff a) -> Aff a

57+withServer test = bracket acquire release (\{ serverMode } -> test serverMode)

58+ where

59+ acquire = do

60+ serverMode <- liftEffect $ Ref.new "ok"

61+ fastify <- liftEffect do

62+ f <- F.fastify {}

63+ omApp <- createOmFastify {} f

64+ postOm (RouteURL "/plain-text-test/double") (handler serverMode) omApp

65+ pure f

66+ void $ F.listen { port: Port 44933, host: Host "0.0.0.0" } fastify

67+ pure { fastify, serverMode }

68+

69+ release { fastify } = F.close fastify

70+

71+ handler serverMode reply = do

72+ mode <- liftEffect $ Ref.read serverMode

73+ case mode of

74+ "badRequest" -> do

75+ void $ F.status (StatusCode 400) reply # liftEffect

76+ void $ F.header "content-type" "text/plain" reply # liftEffect

77+ F.send (unsafeToForeign "invalid value") reply # liftAff

78+ _ -> do

79+ void $ F.status (StatusCode 200) reply # liftEffect

80+ void $ F.header "content-type" "application/json" reply # liftEffect

81+ F.sendJson (unsafeToForeign { doubled: 42 }) reply # liftAff