Fix/pr 240

index.js

@@ -21,10 +21,12 @@ class Analytics {
    *
    * @param {String} writeKey
    * @param {Object} [options] (optional)
-   *   @property {Number} flushAt (default: 20)
-   *   @property {Number} flushInterval (default: 10000)
-   *   @property {String} host (default: 'https://api.segment.io')
-   *   @property {Boolean} enable (default: true)
+   *   @property {Number} [flushAt] (default: 20)
+   *   @property {Number} [flushInterval] (default: 10000)
+   *   @property {String} [host] (default: 'https://api.segment.io')
+   *   @property {Boolean} [enable] (default: true)
+   *   @property {Object} [axiosConfig] (optional)
+   *   @property {Object} [axiosInstance] (default: axios.create(options.axiosConfig))
    */
 
   constructor (writeKey, options) {
@@ -36,6 +38,11 @@ class Analytics {
     this.writeKey = writeKey
     this.host = removeSlash(options.host || 'https://api.segment.io')
     this.path = removeSlash(options.path || '/v1/batch')
+    let axiosInstance = options.axiosInstance
+    if (axiosInstance == null) {
+      axiosInstance = axios.create(options.axiosConfig)
+    }
+    this.axiosInstance = axiosInstance
     this.timeout = options.timeout || false
     this.flushAt = Math.max(options.flushAt, 1) || 20
     this.flushInterval = options.flushInterval || 10000
@@ -126,7 +133,7 @@ class Analytics {
    * Send a screen `message`.
    *
    * @param {Object} message
-   * @param {Function} fn (optional)
+   * @param {Function} [callback] (optional)
    * @return {Analytics}
    */