http_server_mock_erlang

Erlang/OTP runtime for http_server_mock: a WireMock-style HTTP mock server library for Gleam. This package provides the server adapter that runs on the Erlang target using mist and OTP actors.

You need both this package and http_server_mock to use the library. See the http_server_mock README for the full API documentation.

Installation

gleam add http_server_mock http_server_mock_erlang

Usage

Pass the adapter from this package to http_server_mock.new/1:

import gleam/http
import gleam/http/response
import gleam/list
import http_server_mock
import http_server_mock_erlang

pub fn my_test() {
  use server <- http_server_mock.with_stubs(
    http_server_mock.new(http_server_mock_erlang.server()),
    [
      http_server_mock.stub(
        fn(req) { req.method == http.Get && req.path == "/hello" },
        response.new(200) |> response.set_body("world"),
      ),
    ],
  )

  let url = http_server_mock.base_url(server) <> "/hello"
  // ... make HTTP calls ...

  assert list.length(http_server_mock.received(server)) == 1
}

Design notes for this runtime

• Stubs are stored as live Gleam closures directly in the OTP actor’s state (server_impl.gleam): no serialization needed, since the actor and the test process run on the same node.
• simple/with_stubs stop the server after callback returns normally. If the callback panics, stop is not guaranteed to run: the actor and its linked mist listener are cleaned up when the test runner’s BEAM VM exits, not immediately. Full panic-safe cleanup (e.g. via process linking/monitors around the calling test process) is a possible fast-follow, not implemented in 2.0.0.
• The /__admin/* HTTP endpoints from 1.x (/__admin/stubs, /__admin/requests, /__admin/health) are all gone for now. Stubs are closures, not JSON-representable, so there’s nothing to list/add/delete over HTTP; use the Gleam-level http_server_mock.received/ unmatched_requests functions instead of /__admin/requests. A proper admin HTTP surface (likely just introspection, since stubs can’t be serialized) may come back in a future release, but 2.0.0 doesn’t ship a partial one.

License

MIT