Preview template returns error

[seymour7]

When running the following code

    sub_data = {'content': html}

    result = sparkpost_client.templates.preview(
        template_id='newsletter',
        substitution_data=sub_data,
        draft=False
    )

I get the following error:

required field is missing: field 'substitution_data' is required

I think it may be because, in templates.py, line 181:

data=json.dumps(substitution_data))

You can't just simply dump the json, need to append it to a new dict with the "substitution_data" key before doing that.

I'm fairly sure this is the issue because if i change my code like so:

    sub_data = {'substitution_data': {'content': html}}

    result = sparkpost_client.templates.preview(
        template_id=config.item['sparkpost_template'],
        substitution_data=sub_data,
        draft=False
    )

It works.

[richleland]

Hi @seymour7 would you have some time to review #97?