blob: 522cf740ced15c441585bccb14b8f3e02f5d5eb0 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
# Adding a new Diagram Type
To add a new diagram type to the parser you can follow the below steps :point_down:
All the code for the parser resides in [`src`](https://github.com/excalidraw/mermaid-to-excalidraw/tree/master/src) folder and for playground resides in [`playground`](https://github.com/excalidraw/mermaid-to-excalidraw/tree/master/playground) folder.
lets run the playground server in local :point_down:
```bash
yarn start
```
This will start the playground server in port `1234` and open it in browser so you start playing with the playground.
## Update Supported Diagram Types
First step is to add the new diagram type in [`SUPPORTED_DIAGRAM_TYPES`](https://github.com/excalidraw/mermaid-to-excalidraw/blob/master/src/constants.ts#L2).
Once this is done the new diagram type won't be rendered as an image but start throwing error since we don't support parsing the data yet.
## Writing the Diagram Parser
Once the diagram type is added in previous step. Next step is to write the parser to parse the mermaid diagram.
For this create a file named `{{diagramType}}.ts` in [`src/parser`](https://github.com/excalidraw/mermaid-to-excalidraw/tree/master/src/parser) and write a function `parseMermaid{{diagramType}}Diagram` similar to how we [`parseMermaidFlowChartDiagram`](https://github.com/excalidraw/mermaid-to-excalidraw/blob/master/src/parser/flowchart.ts#L256) for parsing flowchart diagram.
The main aim of the parser is :point_down:
1. Determine how elements are connected in the diagram and thus finding arrow and text bindings.
For this you might have to dig in to the parser `diagram.parser.yy` and which attributes to parse for the new diagram.
2. Determine the position and dimensions of each element, for this would be using the `svg`
Once the parser is ready, lets start using it.
Add the diagram type in switch case in [`parseMermaid`](https://github.com/excalidraw/mermaid-to-excalidraw/blob/master/src/parseMermaid.ts#L97) and call the parser for the same.
## Writing the Excalidraw Skeleton Convertor
With the completion of previous step, we have all the data, now we need to transform it so to [ExcalidrawElementSkeleton](https://github.com/excalidraw/excalidraw/blob/master/packages/excalidraw/data/transform.ts#L133) format.
Similar to [`FlowChartToExcalidrawSkeletonConverter`](https://github.com/excalidraw/mermaid-to-excalidraw/blob/master/src/converter/types/flowchart.ts#L24), you have to write the `{{diagramType}}ToExcalidrawSkeletonConverter` which parses the data received in previous step and returns the [ExcalidrawElementSkeleton](https://github.com/excalidraw/excalidraw/blob/master/packages/excalidraw/data/transform.ts#L133).
Thats it, you have added the new diagram type 🥳, now lets test it out!
## Updating the Playground
1. Create a file named `{{diagramType}}.ts` in [`playround/testcases/`](https://github.com/excalidraw/mermaid-to-excalidraw/tree/master/playground/testcases). For reference you can check [`flowchart.ts`](https://github.com/excalidraw/mermaid-to-excalidraw/blob/master/playground/testcases/flowchart.ts).
2. Incase the new diagram type added is present in [`unsupported.ts`](https://github.com/excalidraw/mermaid-to-excalidraw/blob/master/playground/testcases/unsupported.ts) then remove it from there.
3. Verify if the test cases are running fine in playground.
|
