newsletter module

[mdesmet]

Related issues

closes #2558

Short description and why it's useful

Newsletter module supporting subscribe/unsubscribe (can be integrated with mailchimp module (in develop branch of vue-storefront-api) but as long as API is respected with any email provider.

Screenshots of visual changes before/after (if there are any)

Which environment this relates to

Check your case. In case of any doubts please read about Release Cycle

• Test version (https://test.storefrontcloud.io) - this is a new feature or improvement for Vue Storefront. I've created branch from develop branch and want to merge it back to develop
• RC version (https://next.storefrontcloud.io) - this is a stabilisation fix for Release Candidate of Vue Storefront. I've created branch from release branch and want to merge it back to release
• Stable version (https://demo.storefrontcloud.io) - this is an important fix for current stable version. I've created branch from hotfix or master branch and want to merge it back to hotfix

Upgrade Notes and Changelog

• No upgrade steps required (100% backward compatibility and no breaking changes)
• I've updated the Upgrade notes and Changelog on how to port existing VS sites with this new feature

IMPORTANT NOTICE - Remember to update CHANGELOG.md with description of your change

Contribution and currently important rules acceptance

• I read and followed contribution rules
• I read the TypeScript Action Plan and adjusted my PR according to it
• I read about Vue Storefront Modules and I am aware that every new feature should be a module

[pkarw]

Cool stuff, really like this approach. Thanks! Could you please check the failing checks and update changelog?

[mdesmet]

It seems this issue is also on the divante develop branch and not related to my commit.

It seems to be related to using following code parts:

once('__VUE_EXTEND_VUEX__', () => { Vue.use(Vuex) }) in core/store/index.ts

once('__VUE_EXTEND_I18N__', () => { Vue.use(VueI18n) }) in core/i18n/index.ts

If I remove the once wrapping, the tests work, @patzick : can you have a look?

[pkarw]

@mdesmet we need once() to avoid memory leaks in the ssr there must be some other solution to this failing check

[pkarw]

I belive we just must adjust the unit test: core/modules/cart/test/unit/store/mutations.spec.ts @lukeromanowicz

[lukeromanowicz]

@mdesmet I've fixed the failing test from develop branch but there still were some errors coming from yours. To speed things up I've done the following changes:

• split test suite from one integration suite into 4 separate unit test suites
• fixed eslint in mixins and test
• added return values to mixin methods so they can be tested.

I hope that you don't mind that.

[lukeromanowicz]

I've also updated the Changelog and Braking Changes list because the code of this PR is not backward compatible.

[lukeromanowicz]

I approve the code but I'm not really able to fully test it. Maybe @patzick could take a look if it works as expected. Please, remember that there is also API part: vuestorefront/vue-storefront-api#212

Edit:
I talked with OP and it looks like it works correctly. There is no mechanism for keeping information if user has already signed to the newsletter but I suggest doing it in another PR (so we have a base that could be further improved).

[filrak]

Very good piece of code, thanks!

Just please resolve conflicts and optionally get rid of the file i listed below

[pkarw]

@mdesmet could You please resolve the conflicts in order to merge this feature in?