Choreo.Workflow.Render.Mermaid (Choreo v0.9.0)

Copy Markdown View Source

Mermaid.js rendering for Choreo.Workflow orchestration diagrams.

Produces workflow-oriented visualisation:

  • Start — green circle (entry point)
  • End — red circle with thick stroke (terminal)
  • Task — subroutine rectangles (automated steps)
  • Decision — rhombus (conditional branch)
  • Fork — trapezoid (parallel split)
  • Join — trapezoid alt (parallel merge)
  • Compensation — rounded rectangle with red dashed border (rollback)
  • Event — rounded rectangle (trigger / signal)

Edge styles:

  • Sequence — solid grey
  • Compensation — dashed red
  • Retry — dashed orange
  • Failure — dashed grey
  • Timeout — dashed yellow

Swimlanes are rendered as Mermaid subgraphs with optional fill colours.

Further reading

Summary

Functions

theme(name \\ :default, overrides \\ [])

Returns a theme for Choreo.Workflow Mermaid diagrams.

to_mermaid(workflow, opts \\ [])

Renders a workflow to a Mermaid flowchart string.

Functions

theme(name \\ :default, overrides \\ [])

@spec theme(
  atom(),
  keyword()
) :: Choreo.Theme.t()

Returns a theme for Choreo.Workflow Mermaid diagrams.

to_mermaid(workflow, opts \\ [])

@spec to_mermaid(
  Choreo.Workflow.t(),
  keyword()
) :: String.t()

Renders a workflow to a Mermaid flowchart string.

Options

  • :theme — :default, :dark, :warm, :forest, :ocean, or a Choreo.Theme struct
  • :direction — :td (default), :lr, :bt, :rl
  • :highlighted_nodes — list of node IDs to highlight
  • :highlighted_edges — list of edge IDs or {from, to} tuples to highlight
  • Any other option accepted by Yog.Multi.Mermaid.to_mermaid/2

Examples

iex> workflow = Choreo.Workflow.new()
iex> workflow = workflow
...>   |> Choreo.Workflow.add_start(:start)
...>   |> Choreo.Workflow.add_task(:process)
...>   |> Choreo.Workflow.add_end(:end)
...>   |> Choreo.Workflow.connect(:start, :process)
...>   |> Choreo.Workflow.connect(:process, :end)
iex> mermaid = Choreo.Workflow.Render.Mermaid.to_mermaid(workflow)
iex> String.contains?(mermaid, "graph TD")
true
iex> String.contains?(mermaid, "process")
true