ForegroundShow flag is being omitted

[hilariocoelho]

HMS PushKit ForegroundShow flag defaults to true so this field should be sent explicitly with false in order to don't display a notification when the app is in foreground.

Huawei documentation should also be improved in order to say explicitly that the default value of foreground_show flag is true if it is not sent.

Documentation links:
https://developer.huawei.com/consumer/en/doc/development/HMSCore-Guides/android-fgrd-show-0000001050040126
https://developer.huawei.com/consumer/en/doc/development/HMSCore-References/https-send-api-0000001050986197#EN-US_TOPIC_0000001134031085__p163211583235

[Mike-mei]

Thank you for your advice. There is no need to add a default value to a Boolean value, it can be judged according to the meaning of the field.

[hilariocoelho]

I'm not sure if you understood what I tried to explain.

The problem here is that foreground_show flag is being omitted when the value is false (which is the default value due to Go zero-initialization) but Huawei Mobile Service assume the value as true if it is not sent as part of the request JSON's body.

Using this library it is not possible to create a notification with foreground_show as false because HMS will assume it as true because it was not sent. This is a problem I ran into while using appleboy/gorush which led to this and this fix.

Besides the issue itself, I'm also suggesting improving Huawei's documentation by saying that if the flag is not sent in the request's body then it is considered as true.

[Mike-mei]

Thank you for your advice, we will add the default value of foreground_show in the document.

[hilariocoelho]

Specifying in HMS documentation that default value for foreground_show is true is a good improvement but it doesn't fix the issue in this library.

The property defined here has an omitempty JSON tag that prevents the flag from being sent on the request when the value is false. Since the flag is not sent and HMS default value is true it is currently impossible to specify it as false.

I opened PR #9 that removes the omitempty tag.