CreateImageWizard: target env validation

Validation is not enforced on the image output step
when selecting and then deselecting an image type. This
is because the only validation which is set is `Required`.
However, after deselecting an image type the input becomes
a key-value object with all the values set to false. This
commit adds a custom validator to check that at least one
value in the object is set to true. Fixes #575

src/Components/CreateImageWizard/CreateImageWizard.js

@@ -24,6 +24,7 @@ import {
 
 import {
     fileSystemConfigurationValidator,
+    targetEnvironmentValidator,
 } from './validators';
 
 const handleKeyDown = (e, handleClose) => {
@@ -433,7 +434,7 @@ const CreateImageWizard = () => {
                 });
         } }
         defaultArch="x86_64"
-        customValidatorMapper={ { fileSystemConfigurationValidator, } }
+        customValidatorMapper={ { fileSystemConfigurationValidator, targetEnvironmentValidator } }
         schema={ {
             fields: [
                 {

src/Components/CreateImageWizard/steps/imageOutput.js

@@ -50,6 +50,9 @@ export default {
             validate: [
                 {
                     type: validatorTypes.REQUIRED
+                },
+                {
+                    type: 'targetEnvironmentValidator'
                 }
             ],
         }

src/Components/CreateImageWizard/validators/index.js

@@ -1 +1,2 @@
 export { default as fileSystemConfigurationValidator } from './fileSystemConfigurationValidator';
+export { default as targetEnvironmentValidator } from './targetEnvironmentValidator';

src/Components/CreateImageWizard/validators/targetEnvironmentValidator.js

@@ -0,0 +1,14 @@
+const TargetEnvironmentValidator = () => targets => {
+    if (!targets) {
+        return undefined;
+    }
+
+    // at least one of the target environments must
+    // be set to true. This reduces the value to
+    // a single boolean which is a flag for whether
+    // at least one target has been selected or not
+    let valid = Object.values(targets).reduce((prev, curr) => curr || prev, false);
+    return !valid ? 'Please select an image' : undefined;
+};
+
+export default TargetEnvironmentValidator;

src/test/Components/CreateImageWizard/CreateImageWizard.test.js

@@ -221,6 +221,26 @@ describe('Step Image output', () => {
         expect(destination).toBeEnabled();
         expect(destination).toContainElement(required);
     });
+
+    test('selecting and deselecting a tile disables the next button', () => {
+        setUp();
+
+        const [ next, , ] = verifyButtons();
+
+        const awsTile = screen.getByTestId('upload-aws');
+        // this has already been clicked once in the setup function
+        awsTile.click(); // deselect
+
+        const googleTile = screen.getByTestId('upload-google');
+        googleTile.click(); // select
+        googleTile.click(); // deselect
+
+        const azureTile = screen.getByTestId('upload-azure');
+        azureTile.click(); // select
+        azureTile.click(); // deselect
+
+        expect(next).toBeDisabled();
+    });
 });
 
 describe('Step Upload to AWS', () => {