Function rpcAppHandler

packages/blitz-rpc/src/index-server.ts:365–488

(config?: RpcConfig)

type Params = Record<string, unknown>

export function rpcAppHandler(config?: RpcConfig) {
  registerBlitzErrorClasses()
  async function handleRpcRequest(req: Request, segmentData: {params: Promise<Params>}, ctx?: Ctx) {
    const params = await segmentData.params
    const session = ctx?.session
    const resolverMap = await getResolverMap()
    assert(resolverMap, "No query or mutation resolvers found")

    assert(
      Array.isArray(params.blitz),
      "It seems your Blitz RPC endpoint file is not named [[...blitz]].(jt)s. Please ensure it is",
    )

    const relativeRoutePath = (params.blitz as string[])?.join("/")
    const routePath = "/" + relativeRoutePath
    const resolverName = routePath.replace(/(\/api\/rpc)?\//, "")
    const rpcLogger = new RpcLogger(resolverName, config?.logging)

    const loadableResolver = resolverMap?.[routePath]?.resolver
    if (!loadableResolver) {
      throw new Error("No resolver for path: " + routePath)
    }

    const {default: resolver, config: resolverConfig} = await loadableResolver()

    if (!resolver) {
      throw new Error("No default export for resolver path: " + routePath)
    }

    const resolverConfigWithDefaults = {...defaultConfig, ...resolverConfig}

    if (req.method === "HEAD") {
      // We used to initiate database connection here
      return new Response(null, {status: 200})
    }

    if (
      req.method === "POST" ||
      (req.method === "GET" && resolverConfigWithDefaults.httpMethod === "GET")
    ) {
      const body = await req.json()
      if (req.method === "POST" && typeof body.params === "undefined") {
        const error = {message: "Request body is missing the `params` key"}
        rpcLogger.error(error.message)
        return new Response(JSON.stringify({result: null, error}), {status: 400})
      }

      try {
        const data = deserialize({
          json:
            req.method === "POST"
              ? body.params
              : params.params
              ? parse(`${params.params}`)
              : undefined,
          meta:
            req.method === "POST"
              ? body.meta?.params