res-msw

msw bindings for ReScript (formerly known as BuckleScript in Reason)

Installation

Prerequisite: you have installed msw.

npm install -D res-msw

Or if you are using yarn:

yarn add -D res-msw

Usage

Add res-msw to your bsconfig.json:

  ...
  "bs-dependencies": [
+   "res-msw"
  ]
  ...

API

MSW is the root namespace, includes following namespaces and modules:

• rest
• graphql
• Node module
• ServiceWorker module
• Rest module
• GraphQL module

Node module

• setup(array(requestHandler))
• server |> listen()
• server |> close()
• server |> resetHandlers()
• server |> restoreHandlers()
• server |> user(requestHandler)
• rest |> get(string, (req, res, ctx) => { });
• rest |> post(string, (req, res, ctx) => { });
• rest |> put(string, (req, res, ctx) => { });
• rest |> patch(string, (req, res, ctx) => { });
• rest |> delete(string, (req, res, ctx) => { });
• rest |> options(string, (req, res, ctx) => { });

ServiceWorker module

• setup(array(requestHandler))
• worker |> start()
• worker |> stop()
• worker |> resetHandlers()
• worker |> restoreHandlers()
• worker |> user(requestHandler)
• graphql |> query(string, (req, res, ctx) => { });
• graphql |> mutation(string, (req, res, ctx) => { });

Rest module

• res |> mock(array(responseTransformer))
• res |> mockOnce(array(responseTransformer))
• ctx |> status(int)
• ctx |> set(string, string)
• ctx |> delay(int)
• ctx |> fetch(req)
• ctx |> text(string)
• ctx |> json(Js.Json.t)
• ctx |> xml(string)

GraphQL module

• res |> mock(array(responseTransformer))
• res |> mockOnce(array(responseTransformer))
• ctx |> status(int)
• ctx |> set(string, string)
• ctx |> delay(int)
• ctx |> fetch(req)
• ctx |> data(Js.Json.t)
• ctx |> errors(array(Js.Json.t))

Example of Rest

For more example, please refer to MSW_node_test.re and mocks.re.

open MSW

let getRepoInfo = rest |> get("https://api.github.com/repos/:owner/:repo", (
  req,
  res,
  ctx,
) => {
  let {params} = req
  let owner = params->Js.Dict.get("owner")->Belt.Option.getWithDefault("N/A")
  let repo = params->Js.Dict.get("repo")->Belt.Option.getWithDefault("N/A")

  res |> Rest.mock([
    ctx |> Rest.status(200),
    ctx |> Rest.text(`owner: ${owner}, repo: ${repo}`),
  ])
})

let getRepoInfoError =
  rest |> get("https://api.github.com/repos/:owner/:repo", (req, res, ctx) =>
    res |> Rest.mock([ctx |> Rest.status(500), ctx |> Rest.text("Oops")])
  )

let server = Node.setup([getRepoInfo])

server->listen()
server->use(getRepoInfoError)
server->restoreHandlers()
server->resetHandlers()
server->close()

Example of GraphQL

For more example, please refer to MSW_browser.re and mocks.re.

open MSW

let queryUserDetail = graphql |> query("GetUserDetail", (req, res, ctx) => {
  let name = ("name", req.variables["name"])
  let data = Js.Dict.fromList(list{name}) |> Js.Json.object_

  res |> GraphQL.mock([ctx |> GraphQL.status(200), ctx |> GraphQL.data(data)])
})

let queryUserDetailError = graphql |> query("GetUserDetail", (
  req,
  res,
  ctx,
) => {
  let message = (
    "message",
    Js.Json.string(`This is a mocked error: ${req.variables["name"]}`),
  )
  let location = Js.Dict.fromList(list{
    ("line", Js.Json.number(1.0)),
    ("column", Js.Json.number(2.0)),
  })
  let locations = ("locations", Js.Json.objectArray([location]))
  let error = Js.Dict.fromList(list{message, locations}) |> Js.Json.object_

  res |> GraphQL.mock([
    ctx |> GraphQL.status(200),
    ctx |> GraphQL.errors([error]),
  ])
})

let worker = ServiceWorker.setup([queryUserDetail])

worker->start()
worker->use(GetUserDetailError)
worker->restoreHandlers()
worker->resetHandlers()
worker->stop()

Testing the library

npm test

this will compile and execute tests with bs-jest

Contributions

Don't hesitate to open a PR with a new binding - while bumping up the amount of covered bindings in the README. There are tests, use them and write the most simple test you can think of to make sure that the bindings work correctly.