fix retry on all thrown fetch errors (#90)

* retry on all error by default

* update doc

* requested changes

README.md

@@ -24,8 +24,10 @@ Without configuring any parameters, the retry behavior will be as follows:
 - retry for 60s
 - retry inital delay of 100ms with exponential backoff, configurable as a multiplier defaulting to 2
 - retry only on 5xx response
-- retry on all FetchError system errors
+- retry on all errors thrown by fetch
    - see node-fetch error handling: https://github.com/node-fetch/node-fetch/blob/main/docs/ERROR-HANDLING.md
+   - with special behavior to avoid retrying on developer errors (program errors)
+   - this includes `AbortError`'s, `FetchError`'s
 - socket timeout of 30s
 ```js
 const fetch = require('@adobe/node-fetch-retry');

index.js

@@ -100,7 +100,7 @@ function retryInit(options={}) {
             retryOnHttpResponse: ((typeof retryOptions.retryOnHttpResponse === 'function') && retryOptions.retryOnHttpResponse) ||
                 ((response) => { return response.status >= 500; }),
             retryOnHttpError: ((typeof retryOptions.retryOnHttpError === 'function') && retryOptions.retryOnHttpError) ||
-                ((error) => { return shouldRetryOnHttpError(error); }),
+                (() => { return true; }),
             socketTimeout: socketTimeoutValue
         };
     }
@@ -146,25 +146,6 @@ function checkParameters(retryOptions) {
     }
 }
 
-/**
- * Evaluates whether or not to retry based on HTTP error
- * @param {Object} error 
- * @returns Returns true for all FetchError's of type `system`
- */
-function shouldRetryOnHttpError(error) {
-    // special handling for known fetch errors: https://github.com/node-fetch/node-fetch/blob/main/docs/ERROR-HANDLING.md
-    // retry on all errors originating from Node.js core
-    // retry on AbortError caused by network timeouts
-    if (error.name === 'FetchError' && error.type === 'system') {
-        console.error(`FetchError failed with code: ${error.code}; message: ${error.message}`);
-        return true;
-    } else if (error.name === 'AbortError') {
-        console.error(`AbortError failed with type: ${error.type}; message: ${error.message}`);
-        return true;
-    }
-    return false;
-}
-
 /**
  * @typedef {Object} RetryOptions options for retry or false if want to disable retry
  * @property {Integer} retryMaxDuration time (in milliseconds) to retry until throwing an error