Results data-fetching overview

[SachaG]

An overview of how results gets its data:

• Gatsby goes through each chart one by one during its build process.
• For each chart, it looks for an existing chartId.json file A) on the local disk or B) at a predefined URL.
• If the file exists, it uses that.
• If not, it generates a GraphQL query and runs it against the API.

If running locally in dev mode:

• the build process also creates a JSON file containing the results of the API call
• I then commit the updated data as part of the surveys repo and push it to GitHub.

Why

Two reasons why we rely on "static" files:

• Loading a file is way faster than hitting an API, even if the result is cached.
• In the event of the API going down or not running in the future or whatever reason, we can still rebuild the results site with nothing but the JSON files.