Add embeddable charts

[jules2689]

What this does

This adds the option to embed a chart outside of the blazer engine.

<%= render "blazer/queries/query", query: query %> will render the chart and all relevant pieces (JS, Views, Helpers, etc).

params can be provided, just like in a dashboard, to allow variables to be passed in. The API is the same

Combined with ahoy, I was able to embed this in my app:

I tried to make this as seamless as possible, and the Blazer::Query activerecord call + render call is the simplest API I could think of 😄

Addresses part of #24 (#24 (comment))

Notes

• I chose not to use the _query.html.erb file in the dashboard (from where I took much of the view code) as I intended to also embed some JS and stylesheet tags.
• While the global var check in the view is a little iffy, I felt it was better than including JS/CSS many times. I also thought it was nicer than asking the user to include those in their application view code.
• I extracted the relevant CSS classes to a chart.css file so we can load that separately.
• Open to changing any of these decisions, of course 😄

[jules2689]

This is required so we can call blazer_js_var.
I originally has this in my app, but I didn't like the feeling of this extra step. I wanted to get to a simple API of just a render call + activerecord call.

I don't think this is a concern, especially as we have prefixed all methods with blazer_.

Can anyone think of trouble this could cause?

[jules2689]

Taken from https://github.com/ankane/blazer/blob/master/app/views/blazer/dashboards/show.html.erb#L35-L50

I chose not to use this fragment there as I also wanted to embed some stylesheet_link_tag and javascript_include_tag and we had a call to rootPath as well.

[ankane]

Hey @jules2689, thanks for the PR 👍 This is a neat idea, but it's outside the scope of what I'd like to support right now.

[jules2689]

Hey @ankane, Many thanks for this gem! 💎

No worries.

Are there any thoughts you can share about why this is outside of that scope, or a doc I can read? 😄

As an aside, #24 is open and suggests that this is a desirable feature. Might I suggest closing or updating that issue to avoid future confusion? 🙇

[ankane]

Re scope: I think it's simplest for Blazer to be treated as a separate product (that just happens to be mounted on your app), so Rails-specific features are generally discouraged.

Re #24: Sorry about the confusion - I've updated it.

[jules2689]

Makes sense, I don't think this would be difficult to make work from inside the app itself.
I'll report back with a guide on that, if I do :)

[jules2689]

Got it to work!
https://gist.github.com/jules2689/e0a90e0c58cea52969e531a60d0915e4

One thing that would be nice is if there was a single JS file and single CSS file to include.
e.g.
assets/chart-bundle.js included

• blazer/moment
• blazer/moment-timezone-with-data
• blazer/Chart.js
• blazer/chartkick
• blazer/stupidtable
• blazer/stupidtable-custom-settings
• blazer/queries
• blazer/routes

And assets/charts.css included the CSS from this PR.

Thoughts on that @ankane? It would make this much neater and could help blazer by separating the JS and CSS to concerns?

[ankane]

Great, thanks for sharing. Re files: you should be able to add that to the instructions ("create app/assets/chart-bundle.js with ...). I don't think it makes sense to make internal changes for unsupported features.

[jules2689]

e files: you should be able to add that to the instructions ("create app/assets/chart-bundle.js with ...).

Done.

Closing this, people searching can find the link and see the gist here: https://gist.github.com/jules2689/e0a90e0c58cea52969e531a60d0915e4