[GNC-dev] Thoughts on new Finance::Quote modules that require an API Key

[John Ralls]

> On Jun 15, 2019, at 9:17 AM, Vincent Lucarelli <vincent.lucarelli at gmail.com> wrote:
> 
> Hi,
> 
> We are working on the next release of Finance::Quote and will try to add https://iexcloud.io/ <https://iexcloud.io/> as a new module.
> 
> Like Alphavantage, users will need to register and get an API key.
> 
> Since GnuCash is a major user of Finance::Quote, I wanted to get opinions on how to handle API keys.  I have two initial ideas:
> 
> 
> 1. Each Finance::Quote module expects a module specific environment variable and GnuCash would need to update the Preferences > Online Quotes pane for each API key.
> 
> 2. We invent a more global environment variable that can hold multiple API keys. For example, something like
> 
> FQ_API_KEYS=ALPHAVANTAGE_API_KEY:XXXXXXXXXXXXXXXX;IEXCLOUD_API_KEY:sk_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> 
> 
> The problem with the first approach is that GnuCash preferences need to change with each addition.
> 
> The problems wit the second approach are usability and parsing (do we assume no service would ever include : or ; in the API key?).  The later could be solved with json formatting, but that is even worse for users.
> 
> 
> 
> Appreciate any suggestions.

Vince,

Excellent news, thanks for stepping up to help Erik out.

';' in your FQ_API_KEYS will have to be quoted to keep the shell from interpreting it, and any quotes in the key would have to be escaped even with separate environment variables per service. Telling users to escape the delimiter character and quotes is easier than teaching them to format a JSON string. e.g FQ_API_KEYS="AlphaVantage:xxxxxxxxx\"xxxx\:xxxxxx...". The real problem with that is that it breaks backward compatibility with GnuCash, which sets ALPHAVANTAGE_API_KEY when the preference is set. That could be worked around by continuing to look for the older environment variable, or telling users to set the new environment variable themselves, which they'd need to do anyway to use a new service until we rewrote the preference item. Note that we're two weeks away from our next release, so that change would be in the September release at the earliest.

Environment variables are clumsy. Might you consider an alternative, perhaps a "set_key(service, key)" function on the Finance::Quote object? 

Regards,
John Ralls