Render a graph query result as a Mermaid flowchart string.
The input is what AshNeo4j.Cypher.run/2 (and AshNeo4j.Neo4jHelper) return —
a %Bolty.Response{} or the {:ok, response} tuple. The output is a plain
string, with no Kino dependency, so it renders anywhere a Mermaid flowchart
is accepted: Kino.Mermaid.new/1 in the AshNeo4j livebook, Artefact import, or
a Markdown fence.
Graph values in the result rows are rendered structurally:
%Bolty.Types.Node{}→ a flowchart noden<id>["Label<br/>key: value"], showing its labels and stored (graph, not Ash-cast) properties.%Bolty.Types.Relationship{}→ a directed edgen<start> -->|TYPE| n<end>.%Bolty.Types.Path{}→ its nodes and relationships, with edge direction reconstructed from the path's traversal sequence.
Nodes are de-duplicated by graph id, so the same node returned in several rows appears once. Scalars (strings, numbers, points, …) in the result are ignored — only graph entities are drawn.
Options
:direction— flowchart direction,"TD"(default),"LR","BT","RL".:properties—true(default, all stored properties),false(labels only), or a list of property names to keep, in that order.
Examples
iex> node = %Bolty.Types.Node{id: 0, labels: ["Person"], properties: %{"name" => "Bill"}}
iex> AshNeo4j.Mermaid.flowchart(%Bolty.Response{results: [%{"n" => node}]})
"flowchart TD\n n0[\"Person<br/>name: Bill\"]"
iex> a = %Bolty.Types.Node{id: 1, labels: ["Person"], properties: %{}}
iex> b = %Bolty.Types.Node{id: 2, labels: ["Movie"], properties: %{}}
iex> r = %Bolty.Types.Relationship{id: 9, type: "ACTED_IN", start: 1, end: 2}
iex> AshNeo4j.Mermaid.flowchart({:ok, %Bolty.Response{results: [%{"a" => a, "r" => r, "b" => b}]}})
"flowchart TD\n n1[\"Person\"]\n n2[\"Movie\"]\n n1 -->|ACTED_IN| n2"
iex> node = %Bolty.Types.Node{id: 0, labels: ["Person"], properties: %{"name" => "Bill"}}
iex> AshNeo4j.Mermaid.flowchart(%Bolty.Response{results: [%{"n" => node}]}, properties: false)
"flowchart TD\n n0[\"Person\"]"Summary
Functions
Renders a graph result as a Mermaid flowchart string. See the module docs for accepted inputs and options.
Renders the most recently captured query result as a flowchart string.
Stops capturing: detaches the telemetry handler and discards the stashed result. Idempotent.
Functions
@spec flowchart( Bolty.Response.t() | {:ok, Bolty.Response.t()} | {:error, term()} | list(), keyword() ) :: String.t()
Renders a graph result as a Mermaid flowchart string. See the module docs for accepted inputs and options.
Renders the most recently captured query result as a flowchart string.
Requires a prior tap/0 and at least one successful query since. opts are
passed to flowchart/2. Raises if nothing has been captured.
@spec tap() :: :ok
Starts capturing the most recent query result, for last/1.
Attaches a [:ash_neo4j, :query] telemetry handler (see AshNeo4j.Cypher.run/2)
that stashes the most recent successful %Bolty.Response{} containing graph
entities (nodes/relationships/paths) in a small Agent — so a plain scalar or
stat query between graph queries won't clobber the captured view. Idempotent.
Pair with untap/0. Intended for interactive use (livebook, IEx); the rest of
the library never attaches a handler, so without tap/0 the seam costs nothing.
Example
AshNeo4j.Mermaid.tap()
AshNeo4j.Cypher.run("MATCH (n:Person)-[r]->(m) RETURN n, r, m")
AshNeo4j.Mermaid.last() |> Kino.Mermaid.new()@spec untap() :: :ok
Stops capturing: detaches the telemetry handler and discards the stashed result. Idempotent.