Function attach

src/effector/attach.ts:22–134

(config: any)

import {Cmd, Node, Stack} from './index.h'

export function attach(config: any) {
  let injected
  ;[config, injected] = processArgsToConfig(config, true)
  const errorTitle = generateErrorTitle('attach', injected)
  let {source, effect, mapParams, domain} = config
  if (is.effect(effect)) {
    assert(
      isVoid(domain),
      '`domain` can only be used with a plain function',
      errorTitle,
    )
  }
  const attached = createEffect(config, injected)
  setMeta(attached, 'attached', true)
  setUnitTrace(attached, getUnitTrace(attach))
  const {runner} = getGraph(attached).scope as {runner: Node}
  let runnerSteps: Array<Cmd>
  const runnerFnStep = (upd: any, _: any, stack: Stack) => {
    const {params, req, handler} = upd
    const anyway = attached.finally
    const rj = onSettled(params, req, false, anyway, stack)
    const sourceData = stack.a
    const isEffectHandler = is.effect(handler)
    let ok = true
    let computedParams
    if (mapParams) {
      ;[ok, computedParams] = runFn(mapParams, rj, [params, sourceData])
    } else {
      computedParams = source && isEffectHandler ? sourceData : params
    }
    if (ok) {
      if (isEffectHandler) {
        launch({
          target: handler as any,
          params: {
            params: computedParams,
            req: {
              rs: onSettled(params, req, true, anyway, stack),
              rj,
            },
          },
          page: stack.page,
          defer: true,
          meta: stack.meta,
        })
      } else {
        upd.args = [sourceData, computedParams]
        return true
      }
    }
  }
  if (source) {
    runner.scope.runnerFn = runnerFnStep
    let state
    if (is.store(source)) {
      state = source
      own(state, [attached])
    } else {