alt-fetch plugin tests: coverage 100%, all pass (ref. #8)

__tests__/plugins/alt-fetch.test.js

@@ -58,7 +58,7 @@ describe("plugin: alt-fetch", () => {
     expect(self.LibResilientPlugins[0].name).toEqual('alt-fetch');
   });
   
-  test("it should fail upon bad config", () => {
+  test("it should fail with bad config", () => {
     self.LibResilientConfig = {
         plugins: {
             'alt-fetch':{
@@ -70,7 +70,7 @@ describe("plugin: alt-fetch", () => {
     expect(()=>{require("../../plugins/alt-fetch.js")}).toThrow(Error);
   });
   
-  test("it should fetch the content", async () => {
+  test("it should fetch the content, trying all configured endpoints (if fewer or equal to concurrency setting)", async () => {
     require("../../plugins/alt-fetch.js");
     
     global.fetch.mockImplementation((url, init) => {
@@ -92,7 +92,50 @@ describe("plugin: alt-fetch", () => {
     
     const response = await self.LibResilientPlugins[0].fetch('https://resilient.is/test.json');
     
-    expect(fetch).toHaveBeenCalled();
+    expect(fetch).toHaveBeenCalledTimes(3);
+    expect(await response.json()).toEqual({test: "success"})
+    expect(response.url).toEqual('https://resilient.is/test.json')
+  })
+  
+  test("it should fetch the content using, trying <concurrency> random endpoints out of all configured (if more than concurrency setting)", async () => {
+    
+    self.LibResilientConfig = {
+        plugins: {
+            'alt-fetch':{
+              endpoints: [
+                'https://alt.resilient.is/test.json',
+                'https://error.resilientis/test.json',
+                'https://timeout.resilientis/test.json',
+                'https://alt2.resilient.is/test.json',
+                'https://alt3.resilient.is/test.json',
+                'https://alt4.resilient.is/test.json'
+              ]
+            }
+        }
+    }
+    
+    require("../../plugins/alt-fetch.js");
+    
+    global.fetch.mockImplementation((url, init) => {
+          const response = new Response(
+                            new Blob(
+                              [JSON.stringify({ test: "success" })],
+                              {type: "application/json"}
+                            ),
+                            {
+                              status: 200,
+                              statusText: "OK",
+                              headers: {
+                                'ETag': 'TestingETagHeader'
+                              },
+                              url: url
+                            });
+          return Promise.resolve(response);
+        });
+    
+    const response = await self.LibResilientPlugins[0].fetch('https://resilient.is/test.json');
+    
+    expect(fetch).toHaveBeenCalledTimes(3);
     expect(await response.json()).toEqual({test: "success"})
     expect(response.url).toEqual('https://resilient.is/test.json')
   })
@@ -102,7 +145,7 @@ describe("plugin: alt-fetch", () => {
 
     const response = await self.LibResilientPlugins[0].fetch('https://resilient.is/test.json');
     
-    expect(fetch).toHaveBeenCalled();
+    expect(fetch).toHaveBeenCalledTimes(3);
     expect(await response.json()).toEqual({test: "success"})
     expect(response.url).toEqual('https://resilient.is/test.json')
     expect(response.headers.has('X-LibResilient-Method')).toEqual(true)
@@ -133,7 +176,7 @@ describe("plugin: alt-fetch", () => {
 
     const response = await self.LibResilientPlugins[0].fetch('https://resilient.is/test.json');
     
-    expect(fetch).toHaveBeenCalled();
+    expect(fetch).toHaveBeenCalledTimes(3);
     expect(await response.json()).toEqual({test: "success"})
     expect(response.url).toEqual('https://resilient.is/test.json')
     expect(response.headers.has('X-LibResilient-Method')).toEqual(true)