Expose storage API

[Sjord]

New methods:

• get_energy_prod_and_cons_data(self, plant_id, storage_sn, date, type=0)
• get_storage_energy_data(self, plant_id, storage_sn, date)
• get_system_status_data(self, plant_id, storage_sn)
• get_energy_overview_data(self, plant_id, storage_sn)
• get_storage_params(self, storage_sn)

[Sjord]

These need some more testing and at least some documentation before I am going to merge this. If you use these, please let me know which functions work best for you, and which data from each function is useful for you.

[Sjord]

This other project also has some storage functions.

[WynandPrivate]

Hi. I'm trying to use your storage API calls, but none of them are working for me.

Example:
storage_data = api.get_storage_energy_data(plant_id,"BKE6A19067", datetime.date.today())

I get the following error message:

raise GrowattApiError(data)

growatt.GrowattApiError: {'result': 0, 'obj': None, 'msg': '504'}

I've used the get_all_device_list API call to get the AC coupled inverter serial number.

[Sjord]

Thanks @wynandmyriota. I have created a separate issue for this problem: Storage API returns 504 error #16

[Sjord]

These methods need better names or namespaces. get_energy_overview_data currently calls newStorageAPI.do?op=getEnergyOverviewData, but this is very similar to newSpaApi.do?op=getEnergyOverview, and I expect the same to exist for other device types.

[Sjord]

I moved the storage and spa calls to their own class. It now works like this:

with GrowattApi() as api:
    api.login(username, password)
    s = api.storage(plant_id, storage_sn)
    print(s.get_system_status_data())

So api.storage returns a storage object with additional storage specific methods.