Feature: Allow custom message on upload error

src/index.js

@@ -235,7 +235,7 @@ export default class ImageTool {
     // @see https://github.com/editor-js/image/pull/49
     const tunes = ImageTool.tunes.concat(this.config.actions);
 
-    return tunes.map(tune => ({
+    return tunes.map((tune) => ({
       icon: tune.icon,
       label: this.api.i18n.t(tune.title),
       name: tune.name,
@@ -290,7 +290,7 @@ export default class ImageTool {
        * Drag n drop file from into the Editor
        */
       files: {
-        mimeTypes: [ 'image/*' ],
+        mimeTypes: ['image/*'],
       },
     };
   }
@@ -399,7 +399,8 @@ export default class ImageTool {
     if (response.success && response.file) {
       this.image = response.file;
     } else {
-      this.uploadingFailed('incorrect response: ' + JSON.stringify(response));
+      const customErrorMessage = typeof response.message === 'string' ? response.message : undefined;
+      this.uploadingFailed('incorrect response: ' + JSON.stringify(response), customErrorMessage);
     }
   }
 
@@ -408,13 +409,14 @@ export default class ImageTool {
    *
    * @private
    * @param {string} errorText - uploading error text
+   * @param {string | undefined} customErrorText - displayed error text
    * @returns {void}
    */
-  uploadingFailed(errorText) {
+  uploadingFailed(errorText, customErrorText) {
     console.log('Image Tool: uploading failed because of', errorText);
 
     this.api.notifier.show({
-      message: this.api.i18n.t('Couldn’t upload image. Please try another.'),
+      message: customErrorText ?? this.api.i18n.t('Couldn’t upload image. Please try another.'),
       style: 'error',
     });
     this.ui.hidePreloader();
@@ -449,10 +451,11 @@ export default class ImageTool {
       /**
        * Wait until the API is ready
        */
-      Promise.resolve().then(() => {
-        this.block.stretched = value;
-      })
-        .catch(err => {
+      Promise.resolve()
+        .then(() => {
+          this.block.stretched = value;
+        })
+        .catch((err) => {
           console.error(err);
         });
     }