WebSequenceDiagrams don't render with Mermaid

[jgwinner]

Description

I'm not sure if this is a bug in mermaid, an issue with my DSL, or a bug in the exporter.

When I generate a WebSequence export, the lines look like this:

title ANS - Dynamic - AllFlows

actor <<Person>>\nAPI User as API User
participant <<Component>>\nAPI Gateway as API Gateway
participant <<Component>>\nManages Event definition as Manages Event definition

Yet in Notion.so, it generates this error:

Unknown error: Error: Lexical error on line 5. Unrecognized text.
... - AllFlows"actor <<Person>>\nAPI User
_______________________^

If I fix that by removing <<Person>>\n it'll generate the same errors for <<Component>>\n

Is this a Mermaid bug, or a Structurizr issue?

Also, I find Structurizr uses -> when I think the expectation is ->> and -->> but maybe that's me?

Steps to reproduce

1. Create a Structurizr dynamic view.
2. Export via structurizr.sh export -w ANS.dsl -f websequencediagrams
3. Create a Mermaid code block in Notion.so
4. type 'sequenceDiagram' and press enter.
5. Paste in the *.wsd file from step 2

Screenshot

Fixing that gives:

Code sample

workspace "test WebSequence" {

    model {
        customer = person "Customer"
        onlineBookStore = softwareSystem "Online book store" {
            webapp = container "Web Application"
            database = container "Database"
        }

        customer -> webapp "Browses and makes purchases using"
        webapp -> database "Reads from and writes to"
    }

    views {
        
        dynamic onlineBookStore {
            title "Request past orders feature"
            customer -> webapp "Requests past orders from"
            webapp -> database "Queries for orders using"
            autoLayout lr
        }
    }
    
}

Configuration

structurizr-cli: 1.33.1
structurizr-java: 1.26.1
structurizr-dsl: 1.32.0
structurizr-export: 1.16.1
structurizr-import: v1.5.0
Java: 11.0.20.1/Homebrew (/opt/homebrew/Cellar/openjdk@11/11.0.20.1/libexec/openjdk.jdk/Contents/Home)
OS: Mac OS X 14.0 (aarch64)

Severity

Minor

Priority

Low

Resolution

I have no budget and there's no rush, please fix this for free

More information

I might be able to fix myself, but we may be subscribing to the cloud service anyway.

[simonbrowndotje]

Is WebSequenceDiagrams compatible with Mermaid?

Edit: no, it doesn't seem to be, so I'm not sure why you're trying to render a WebSequenceDiagrams definition with Mermaid. Moving to a discussion...

[jgwinner]

Ah, it looks like Websequencediagrams and Mermaid's implementation are just slightly different.

I'll follow up with Mermaid.

Sorry to trouble you!

[jgwinner]

I opened a ticket with them: mermaid-js/mermaid#4943

[simonbrowndotje]

You can export sequence diagrams with the Mermaid exporter; see https://docs.structurizr.com/export/mermaid for details.

For example:

Granted it's not quite as visually appealing as the WebSequenceDiagrams renderer, but all rendering tools have trade-offs.

[jgwinner]

Ah, thank you - I'm embarrassed, I missed that option.