Add custom fetcher config option

src/model.ts

@@ -7,7 +7,8 @@ import {
   Request,
   RequestVerbs,
   JsonapiResponse,
-  ResponseError
+  ResponseError,
+  Fetcher
 } from "./request"
 import { WritePayload } from "./util/write-payload"
 import { flipEnumerable, getNonEnumerables } from "./util/enumerables"
@@ -65,6 +66,7 @@ export interface ModelConfiguration {
   keyCase: KeyCase
   strictAttributes: boolean
   logger: ILogger
+  fetcher: Fetcher
 }
 export type ModelConfigurationOptions = Partial<ModelConfiguration>
 
@@ -147,7 +149,7 @@ export const applyModelConfig = <T extends typeof SpraypaintBase>(
 
   for (k in config) {
     if (config.hasOwnProperty(k)) {
-      ModelClass[k] = config[k]
+      ;(ModelClass[k] as any) = config[k]
     }
   }
 
@@ -179,6 +181,8 @@ export class SpraypaintBase {
   static currentClass: typeof SpraypaintBase = SpraypaintBase
   static beforeFetch: BeforeFilter | undefined
   static afterFetch: AfterFilter | undefined
+  static fetcher: Fetcher = (input: string, init?: RequestInit) =>
+    fetch(input, init)
 
   private static _typeRegistry: JsonapiTypeRegistry
   private static _IDMap: IDMap
@@ -687,10 +691,7 @@ export class SpraypaintBase {
       )
     }
 
-    return {
-      id: this.id,
-      type: this.klass.jsonapiType
-    }
+    return { id: this.id, type: this.klass.jsonapiType }
   }
 
   get errors(): ValidationErrors<this> {
@@ -950,7 +951,11 @@ export class SpraypaintBase {
   async destroy(): Promise<boolean> {
     const url = this.klass.url(this.id)
     const verb = "delete"
-    const request = new Request(this._middleware(), this.klass.logger)
+    const request = new Request(
+      this._middleware(),
+      this.klass.fetcher,
+      this.klass.logger
+    )
     let response: any
 
     try {
@@ -980,9 +985,14 @@ export class SpraypaintBase {
   ): Promise<boolean> {
     let url = this.klass.url()
     let verb: RequestVerbs = "post"
-    const request = new Request(this._middleware(), this.klass.logger, {
-      patchAsPost: this.klass.patchAsPost
-    })
+    const request = new Request(
+      this._middleware(),
+      this.klass.fetcher,
+      this.klass.logger,
+      {
+        patchAsPost: this.klass.patchAsPost
+      }
+    )
     const payload = new WritePayload(this, options.with)
     let response: any
 

src/request.ts

@@ -9,21 +9,26 @@ export interface JsonapiResponse extends Response {
   jsonPayload: JsonapiResponseDoc
 }
 
-export interface RequestConfig {
+export type Fetcher = (url: string, options: RequestInit) => Promise<any>
+
+interface RequestConfig {
   patchAsPost: boolean
 }
 
 export class Request {
   middleware: MiddlewareStack
+  fetcher: Fetcher
   config: RequestConfig
   private logger: ILogger
 
   constructor(
     middleware: MiddlewareStack,
+    fetcher: Fetcher,
     logger: ILogger,
     config?: RequestConfig
   ) {
     this.middleware = middleware
+    this.fetcher = fetcher
     this.logger = logger
     this.config = Object.assign({ patchAsPost: false }, config)
   }
@@ -104,7 +109,7 @@ export class Request {
     let response
 
     try {
-      response = await fetch(url, options)
+      response = await this.fetcher(url, options)
     } catch (e) {
       throw new ResponseError(null, e.message, e)
     }

src/scope.ts

@@ -336,7 +336,11 @@ export class Scope<T extends SpraypaintBase = SpraypaintBase> {
     if (qp) {
       url = `${url}?${qp}`
     }
-    const request = new Request(this.model.middlewareStack, this.model.logger)
+    const request = new Request(
+      this.model.middlewareStack,
+      this.model.fetcher,
+      this.model.logger
+    )
     const response = await request.get(url, this.fetchOptions())
     refreshJWT(this.model, response)
     return response.jsonPayload

test/integration/custom-fetcher.test.ts

@@ -0,0 +1,70 @@
+import { expect, sinon } from "../test-helper"
+import fetchMock = require("fetch-mock")
+import { Model, SpraypaintBase } from "../../src"
+
+describe("Custom fetcher", () => {
+  let spy1: sinon.SinonSpy
+  let spy2: sinon.SinonSpy
+
+  let ApplicationRecord: typeof SpraypaintBase
+  let Author: typeof SpraypaintBase
+  let Person: typeof SpraypaintBase
+
+  beforeEach(() => {
+    const fetcher = (a: any, b: any) =>
+      Promise.resolve(
+        new Response(
+          JSON.stringify({
+            data: {
+              id: "1",
+              type: "people",
+              attributes: {
+                firstName: "John"
+              }
+            }
+          })
+        )
+      )
+
+    spy1 = sinon.spy(fetcher)
+    spy2 = sinon.spy(fetcher)
+
+    @Model({
+      baseUrl: "http://example.com",
+      apiNamespace: "/api/v1"
+    })
+    class Base extends SpraypaintBase {}
+    ApplicationRecord = Base
+
+    @Model({
+      jsonapiType: "authors",
+      fetcher: spy1
+    })
+    class A extends ApplicationRecord {}
+    Author = A
+
+    @Model({ jsonapiType: "people" })
+    class B extends ApplicationRecord {
+      static fetcher = spy2
+    }
+    Person = B
+  })
+
+  describe("uses custom fetchers", () => {
+    it("calls a custom fetcher set via config", async () => {
+      await Author.find(1)
+
+      expect(spy1).to.have.been.calledOnce.and.to.have.been.calledWith(
+        "http://example.com/api/v1/authors/1"
+      )
+    })
+
+    it("calls a custom fetcher set via static props", async () => {
+      await Person.find(1)
+
+      expect(spy2).to.have.been.calledOnce.and.to.have.been.calledWith(
+        "http://example.com/api/v1/people/1"
+      )
+    })
+  })
+})