This is the api to be used when optionally handling the integration with the web page, instead of using the default integration provided by mermaid.js.
The core of this api is the render function which, given a graph definition as text, renders the graph/diagram and returns an svg element for the graph.
It is is then up to the user of the API to make use of the svg, either insert it somewhere in the page or do something completely different.
In addition to the render function, a number of behavioral configuration options are available.
These are the default options which can be overridden with the initialization call like so: Example 1:
mermaid.initialize({ flowchart:{ htmlLabels: false } });
Example 2:
<script> var config = { startOnLoad:true, flowchart:{ useMaxWidth:true, htmlLabels:true, curve:'cardinal', }, securityLevel:'loose', }; mermaid.initialize(config); </script>A summary of all options and their defaults is found [here](https://github.com/knsv/mermaid/blob/master/docs/mermaidAPI.md#mermaidapi-configuration-defaults). A description of each option follows below.
theme , the CSS style sheet
theme - Choose one of the built-in themes:
- default
- forest
- dark
- neutral. To disable any pre-defined mermaid theme, use "null".
themeCSS - Use your own CSS. This overrides theme.
"theme": "forest", "themeCSS": ".node rect { fill: red; }"
fontFamily The font to be used for the rendered diagrams. Default value is \"trebuchet ms\", verdana, arial;
This option decides the amount of logging to be used.
- debug: 1
- info: 2
- warn: 3
- error: 4
- fatal: (default) 5
Sets the level of trust to be used on the parsed diagrams.
- strict: (default) tags in text are encoded, click functionality is disabeled
- loose: tags in text are allowed, click functionality is enabled
This options controls whether or mermaid starts when the page loads Default value true.
This options controls whether or arrow markers in html code will be absolute paths or an anchor, #. This matters if you are using base tag settings. Default value false.
The object containing configurations specific for flowcharts
Flag for setting whether or not a html tag should be used for rendering labels on the edges. Default value true.
How mermaid renders curves for flowcharts. Possible values are
- basis
- linear default
- cardinal
The object containing configurations specific for sequence diagrams
margin to the right and left of the sequence diagram. Default value 50.
margin to the over and under the sequence diagram. Default value 10.
Margin between actors. Default value 50.
Width of actor boxes Default value 150.
Height of actor boxes Default value 65.
Margin around loop boxes Default value 10.
margin around the text in loop/alt/opt boxes Default value 5.
margin around notes. Default value 10.
Space between messages. Default value 35.
mirror actors under diagram. Default value true.
Depending on css styling this might need adjustment. Prolongs the edge of the diagram downwards. Default value 1.
when this flag is set the height and width is set to 100% and is then scaling with the available space if not the absolute space required is used. Default value true.
This will display arrows that start and begin at the same node as right angles, rather than a curve Default value false.
This will show the node numbers Default value false.
The object containing configurations specific for gantt diagrams*
Margin top for the text over the gantt diagram Default value 25.
The height of the bars in the graph Default value 20.
The margin between the different activities in the gantt diagram. Default value 4.
Margin between title and gantt diagram and between axis and gantt diagram. Default value 50.
The space allocated for the section name to the left of the activities. Default value 75.
Vertical starting position of the grid lines. Default value 35.
Font size ... Default value 11.
font family ... Default value '"Open-Sans", "sans-serif"'.
The number of alternating section styles. Default value 4.
Datetime format of the axis. This might need adjustment to match your locale and preferences Default value '%Y-%m-%d'.
Function that renders an svg with a graph from a chart definition. Usage example below.
mermaidAPI.initialize({
startOnLoad:true
});
$(function(){
const graphDefinition = 'graph TB\na-->b';
const cb = function(svgGraph){
console.log(svgGraph);
};
mermaidAPI.render('id1',graphDefinition,cb);
});
id
the id of the element to be renderedtxt
the graph definitioncb
callback which is called after rendering is finished with the svg code as inparam.container
selector to element in which a div with the graph temporarily will be inserted. In one is provided a hidden div will be inserted in the body of the page instead. The element will be removed when rendering is completed.
<script> var config = { theme:'default', logLevel:'fatal', securityLevel:'strict', startOnLoad:true, arrowMarkerAbsolute:false, flowchart:{ htmlLabels:true, curve:'linear', }, sequence:{ diagramMarginX:50, diagramMarginY:10, actorMargin:50, width:150, height:65, boxMargin:10, boxTextMargin:5, noteMargin:10, messageMargin:35, mirrorActors:true, bottomMarginAdj:1, useMaxWidth:true, rightAngles:false, showSequenceNumbers:false, }, gantt:{ titleTopMargin:25, barHeight:20, barGap:4, topPadding:50, leftPadding:75, gridLineStartPadding:35, fontSize:11, fontFamily:'"Open-Sans", "sans-serif"', numberSectionStyles:4, axisFormat:'%Y-%m-%d', } }; mermaid.initialize(config); </script>