fix: return http error code and message when failing to connect to score-api

src/utils.spec.js

@@ -147,19 +147,6 @@ describe('utils', () => {
         expect(_validate({})).rejects.toEqual(result.error);
       });
     });
-
-    describe('when the fetch request is failing with not network error', () => {
-      test('rejects with the error', () => {
-        const result = new Error('Oh no');
-        fetch.mockReturnValue({
-          json: () => {
-            throw result;
-          }
-        });
-
-        expect(_validate({})).rejects.toEqual(result);
-      });
-    });
   });
   describe('getScores', () => {
     const payload = {
@@ -314,19 +301,6 @@ describe('utils', () => {
         expect(_getScores({})).rejects.toEqual(result.error);
       });
     });
-
-    describe('when the fetch request is failing with not network error', () => {
-      test('rejects with the error', () => {
-        const result = new Error('Oh no');
-        fetch.mockReturnValue({
-          json: () => {
-            throw result;
-          }
-        });
-
-        expect(_getScores({})).rejects.toEqual(result);
-      });
-    });
   });
   describe('getVp', () => {
     const payload = {
@@ -458,18 +432,5 @@ describe('utils', () => {
         expect(_getVp({})).rejects.toEqual(result.error);
       });
     });
-
-    describe('when the fetch request is failing with not network error', () => {
-      test('rejects with the error', () => {
-        const result = new Error('Oh no');
-        fetch.mockReturnValue({
-          json: () => {
-            throw result;
-          }
-        });
-
-        expect(_getVp({})).rejects.toEqual(result);
-      });
-    });
   });
 });

src/utils.ts

@@ -134,7 +134,6 @@ ajv.addKeyword({
   errors: true
 });
 
-
 // Custom URL format to allow empty string values
 // https://github.com/snapshot-labs/snapshot.js/pull/541/files
 ajv.addFormat('customUrl', {
@@ -333,15 +332,27 @@ export async function getScores(
       headers: scoreApiHeaders,
       body: JSON.stringify({ params })
     });
-    const obj = await res.json();
+    let json: Record<string, any> = {};
+
+    try {
+      json = await res.json();
+    } catch (e) {
+      if (!res.ok) {
+        return Promise.reject({
+          code: res.status,
+          message: res.statusText,
+          data: ''
+        });
+      }
+    }
 
-    if (obj.error) {
-      return Promise.reject(obj.error);
+    if (json.error) {
+      return Promise.reject(json.error);
     }
 
     return options.returnValue === 'all'
-      ? obj.result
-      : obj.result[options.returnValue || 'scores'];
+      ? json.result
+      : json.result[options.returnValue || 'scores'];
   } catch (e) {
     if (e.errno) {
       return Promise.reject({ code: e.errno, message: e.toString(), data: '' });
@@ -401,7 +412,20 @@ export async function getVp(
 
   try {
     const res = await fetch(options.url, init);
-    const json = await res.json();
+    let json: Record<string, any> = {};
+
+    try {
+      json = await res.json();
+    } catch (e) {
+      if (!res.ok) {
+        return Promise.reject({
+          code: res.status,
+          message: res.statusText,
+          data: ''
+        });
+      }
+    }
+
     if (json.error) return Promise.reject(json.error);
     if (json.result) return json.result;
   } catch (e) {
@@ -455,7 +479,20 @@ export async function validate(
 
   try {
     const res = await fetch(options.url, init);
-    const json = await res.json();
+    let json: Record<string, any> = {};
+
+    try {
+      json = await res.json();
+    } catch (e) {
+      if (!res.ok) {
+        return Promise.reject({
+          code: res.status,
+          message: res.statusText,
+          data: ''
+        });
+      }
+    }
+
     if (json.error) return Promise.reject(json.error);
     return json.result;
   } catch (e) {

test/e2e/utils/getScores.spec.ts

@@ -29,4 +29,22 @@ describe('test getScores', () => {
       data: ''
     });
   });
+
+  test('getScores should return a promise rejection with JSON-RPC format on network error', async () => {
+    expect.assertions(1);
+    await expect(
+      getScores(
+        'test.eth',
+        [],
+        '1',
+        ['0x9e8f6CF284Db7a80646D9d322A37b3dAF461F8DD'],
+        'latest',
+        'https://snapshot.org'
+      )
+    ).to.rejects.toEqual({
+      code: 405,
+      message: 'Method Not Allowed',
+      data: ''
+    });
+  });
 });