[CT-1452] Support mermaid in markdown

[il-dat]

Describe the feature

I have seen many places where mermaid can rich the documentation very well. That's why I've tried to utilize it within dbt project, but it doesn't work yet.

Additional context

• dbt model doc
• dbt macro doc
• general doc

Who will this benefit?

• dbt docs site will become richer with mermaid diagrams
• open the door for programmatically generating the diagrams/flows within md files, even use it for building ERD Sample mermaid for ERD:

  erDiagram
  CUSTOMER ||--o{ ORDER : places
  CUSTOMER {
      string name
      string custNumber
      string sector
  }
  ORDER ||--|{ LINE-ITEM : contains
  ORDER {
      int orderNumber
      string deliveryAddress
  }
  LINE-ITEM {
      string productCode
      int quantity
      float pricePerUnit
  }

[jtcohen6]

Agree that this would be cool! It's unlikely something that we'll be prioritizing ourselves in the near future, given our ongoing commitment to dbt-docs right now can only be parity + stability. But perhaps as a hackathon project for someone interested??

dbt-docs is still written in Angular (!). After a quick search, it looks like there are some resources online for how to integrate the two. Ideal UX here would be the ability to add code blocks with ```mermaid, just like in GitHub Markdown.

We'd need to ensure that this is copacetic from a security standpoint. It looks like there have been some issues in the past (https://security.snyk.io/vuln/SNYK-JS-MERMAID-174698), but also that the team behind mermaid is serious about resolving these.

I've also heard some votes in favor of https://github.com/plantuml/plantuml, as a preferable text-to-visual framework for graphs. It sounds like Mermaid might be easier to write, but PlantUML has been around longer, it's more feature-rich, and it has fewer limitations around the edges.

I'm going to call this help_wanted, if anyone wants to give it a spin!

[github-actions[bot]]

This issue has been marked as Stale because it has been open for 180 days with no activity. If you would like the issue to remain open, please comment on the issue or else it will be closed in 7 days.

[github-actions[bot]]

Although we are closing this issue as stale, it's not gone forever. Issues can be reopened if there is renewed community interest. Just add a comment to notify the maintainers.

[matthieucan]

I believe this should be reopened, there is a PR adding mermaid.js support for which maintainers' attention would be really appreciated