2020-02-22 23:20:50 -08:00
# A basic mermaid User-Guide for Beginners
2019-11-07 23:15:53 +01:00
2020-07-15 21:30:23 -07:00
Creating diagrams and charts using mermaid code is simple.
2021-03-04 04:48:58 -08:00
mermaid allows you to dynamically code and modify diagrams.
when called, mermaid renders code definitions into a diagram in SVG format.
2019-11-07 23:15:53 +01:00
2021-03-04 04:48:58 -08:00
>The live editor is enough for most general uses of mermaid
2021-03-11 23:46:59 -08:00
## Absolute beginners are recommended to view the Video [Tutorials](./Tutorials.md) on the Live Editor, to gain a better understanding of mermaid.
2019-11-07 23:15:53 +01:00
2019-11-07 23:37:46 +01:00
2021-03-11 23:46:59 -08:00
## For beginners, there are Four ways you can use mermaid:
2021-03-06 01:59:16 -08:00
1. Using the mermaid [Live Editor ](https://mermaid-js.github.io/mermaid-live-editor/ ).
2021-03-04 04:48:58 -08:00
- Learning the [Syntax ](./n00b-syntaxReference ) would be helpful.
2. Using one of the many [mermaid plugins ](./integrations.md ).
2020-07-25 18:15:37 -07:00
3. Hosting mermaid on a webpage, with an absolute link.
2020-08-21 01:01:06 +08:00
4. Downloading mermaid and hosting it on your Web Page.
2020-07-24 12:30:06 -07:00
2021-03-11 23:46:59 -08:00
**Note: It is our recommendation that you review all approaches, and choose the one that is best for your project.**
>More in depth information can be found on [Usage ](./usage.md ).
2020-09-07 14:02:09 +08:00
2020-07-24 12:30:06 -07:00
# Following any of these examples, you can get started with creating your own diagrams using mermaid code.
2019-11-07 23:15:53 +01:00
2020-02-22 22:16:00 -08:00
## 1. The mermaid live editor:
2019-11-07 23:15:53 +01:00
2020-02-22 22:16:00 -08:00
A great way to get started with mermaid is to visit [The mermaid live editor ](https://mermaidjs.github.io/mermaid-live-editor ).
2019-11-07 23:15:53 +01:00
2020-02-22 19:21:37 -08:00
In the `Code` section one can write or edit raw mermaid code, and instantly `Preview` the rendered result on the panel beside it.
2020-02-22 22:16:26 -08:00
2020-08-21 01:01:06 +08:00
**This is a great way to learn how to define a mermaid diagram.**
2020-07-22 21:28:02 -07:00
2021-03-06 01:59:16 -08:00
The Live Editor opens on a [Flowchart ](./flowchart.md ).
2019-11-07 23:15:53 +01:00
2020-11-15 03:25:02 -08:00
2020-02-22 23:10:08 -08:00
2021-03-01 16:24:48 -08:00
**Saving a Diagram:**
Downloading the image may be a ideal for a majority uses.
2019-11-07 23:15:53 +01:00
2021-03-01 16:24:48 -08:00
The Links and the markdown code can be referenced to display the diagram.
2020-02-22 22:16:00 -08:00
2021-03-02 16:07:34 -08:00
2019-11-07 23:15:53 +01:00
2021-03-06 01:59:16 -08:00
**Configuration**
2021-03-02 16:04:44 -08:00
*The Mermaid configuration* is for configuring the appearance and behavior of mermaid diagrams. An easy introduction to mermaid configuration is found in the [Advanced usage ](./n00b-advanced.md ) section. A complete configuration reference cataloguing default values is found on the [mermaidAPI ](Setup.md ) page.
2019-11-07 23:15:53 +01:00
2020-11-15 03:25:02 -08:00
2019-11-07 23:15:53 +01:00
2020-11-15 03:25:02 -08:00
## 2. Using mermaid plugins:
2019-11-07 23:15:53 +01:00
2020-11-15 03:25:02 -08:00
Thanks to the growing popularity of mermaid, many plugins already allow the generation of mermaid diagrams from within popular applications. An extensive list of applications the support mermaid plugins can be found [here ](./integrations.md ).
2019-11-07 23:15:53 +01:00
2020-09-07 14:02:09 +08:00
**This is covered in greater detail in the [Usage section ](usage.md )**
2019-11-07 23:15:53 +01:00
2021-03-11 18:09:43 -08:00
## 3. Deploying mermaid with Inline JavaScript
2019-11-07 23:15:53 +01:00
2020-02-22 19:21:37 -08:00
This method can be used with any common web server. Apache, IIS, nginx, node express [...], you pick your favourite.
2021-03-11 23:46:59 -08:00
You will need a text editting tool like Notepad++, t can generate an html file. It is then deployed by a web browser (such as Firefox, Chrome, Safari, but not Internet Explorer).
2020-02-22 19:21:37 -08:00
2021-03-11 18:09:43 -08:00
Just create an HTML file locally and open it using a desired browser.
2020-02-22 19:21:37 -08:00
2021-03-11 18:09:43 -08:00
### Written in the html `<body>` section of the web page.
2020-02-22 19:21:37 -08:00
When writing the html file, we give the web browser three instructions inside the html code:
2020-02-27 01:07:25 -08:00
2020-02-22 19:21:37 -08:00
a. A reference for fetching the online mermaid renderer, which is written in Javascript.
2020-02-27 01:06:38 -08:00
2020-02-22 19:21:37 -08:00
b. The mermaid code for the diagram we want to create.
2020-02-27 01:06:38 -08:00
2020-11-15 03:25:02 -08:00
c. The `mermaid.initialize()` call to start the rendering process.
2019-11-07 23:15:53 +01:00
2021-03-11 18:09:43 -08:00
## Three requirements for the mermaidAPI to render a diagram:
2019-11-07 23:15:53 +01:00
2021-03-11 23:46:59 -08:00
### a. A reference to the external CDN in a `<script src>` tag, or a reference to mermaid.js as a separate file.:
2019-11-07 23:15:53 +01:00
2020-09-07 14:02:09 +08:00
```html
2019-11-07 23:15:53 +01:00
< body >
2020-07-22 21:28:02 -07:00
< script src = "https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.min.js" > < / script >
2019-11-07 23:15:53 +01:00
< / body >
```
2021-03-11 18:09:43 -08:00
### b. The embedded mermaid diagram definition inside a `<div class="mermaid">`:
2019-11-07 23:15:53 +01:00
2020-09-07 14:02:09 +08:00
```html
2019-11-07 23:15:53 +01:00
< body >
Here is a mermaid diagram:
< div class = "mermaid" >
graph TD
A[Client] --> B[Load Balancer]
B --> C[Server01]
B --> D[Server02]
< / div >
< / body >
```
2020-07-24 12:30:06 -07:00
**Notes**: every mermaid chart/graph/diagram definition, has to have separate `<div>` tags.
2021-03-11 18:09:43 -08:00
### c. The `mermaid.initialize()` call.
2019-11-07 23:15:53 +01:00
2021-03-11 18:09:43 -08:00
`mermaid.initialize()` calls take all the definitions contained in `<div class="mermaid">` tags it can find in the html body and render. Example:
2021-03-11 23:46:59 -08:00
| Parameter | Description | Type | Values |
| --------- | --------------- | ------ | ---------------------------------------------------- |
|startOnLoad| Toggle for Rendering upon loading | Boolean | true, false |
2019-11-07 23:15:53 +01:00
2020-09-07 14:02:09 +08:00
```html
2019-11-07 23:15:53 +01:00
< body >
< script > mermaid . initialize ( { startOnLoad : true } ) ; < / script >
< / body >
```
2021-03-11 23:46:59 -08:00
**Notes**:You can place `mermaid.initialize()` inside of `mermaid.min.js` or `mermaid.js` , for brevity.
2019-11-07 23:15:53 +01:00
2021-03-11 23:46:59 -08:00
### Here is a full working example of the mermaidAPI being called through the CDN:
2020-07-15 21:30:23 -07:00
2020-09-07 14:02:09 +08:00
```html
2019-11-07 23:15:53 +01:00
< html >
< body >
2020-07-22 21:28:02 -07:00
< script src = "https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.min.js" > < / script >
2019-11-07 23:15:53 +01:00
< script > mermaid . initialize ( { startOnLoad : true } ) ; < / script >
Here is one mermaid diagram:
< div class = "mermaid" >
graph TD
A[Client] --> B[Load Balancer]
2019-11-28 12:34:26 +01:00
B --> C[Server1]
B --> D[Server2]
2019-11-07 23:15:53 +01:00
< / div >
2019-11-28 12:34:26 +01:00
And here is another:
2019-11-07 23:15:53 +01:00
< div class = "mermaid" >
graph TD
2019-11-28 12:34:26 +01:00
A[Client] -->|tcp_123| B(Load Balancer)
B -->|tcp_456| C[Server1]
B -->|tcp_456| D[Server2]
2019-11-07 23:15:53 +01:00
< / div >
< / body >
< / html >
```
2021-03-11 23:46:59 -08:00
**Another full example:**
In this example mermaid.js is referenced as a separate JavaScript file, in an example Path.
2020-09-07 14:02:09 +08:00
```html
2020-07-22 21:31:49 -07:00
< html lang = "en" >
< head >
< meta charset = "utf-8" >
< / head >
< body >
< div class = "mermaid" >
graph LR
A --- B
B-->C[fa:fa-ban forbidden]
B-->D(fa:fa-spinner);
< / div >
< div class = "mermaid" >
graph TD
A[Client] --> B[Load Balancer]
B --> C[Server1]
B --> D[Server2]
< / div >
2021-03-11 23:46:59 -08:00
< script src = "The \Path \In \Your \PC \mermaid.js" ></ script >
2020-07-22 21:31:49 -07:00
< script > mermaid . initialize ( { startOnLoad : true } ) ; < / script >
< / body >
< / html >
2020-07-22 21:28:02 -07:00
```
2021-03-11 23:46:59 -08:00
---
## 4. Adding mermaid as a dependency.
2019-11-07 23:15:53 +01:00
2021-03-11 23:46:59 -08:00
1. install node v10 or 12, which would have npm
2020-08-21 01:01:06 +08:00
2021-03-11 23:46:59 -08:00
2. download yarn using npm by entering the command below:
npm install -g yarn
3. After yarn installs, enter the following command:
yarn add mermaid
4. To add Mermaid as a Dev Dependency
yarn add --dev mermaid
**Three additional comments from Knut Sveidqvist, creator of mermaid:**
- In early versions of mermaid, the `<script src>` tag was invoked in the `<head>` part of the web page. Nowadays we can place it in the `<body>` as seen above. Older parts of the documentation frequently reflects the previous way which still works.
2019-11-07 23:15:53 +01:00
2021-03-11 23:46:59 -08:00
- We initialize the mermaid rendering with `mermaid.initialize()` directly in the html code.In principle this could be done through placing `mermaid.initialize()` inside of `mermaid.min.js` . We would then eliminate the need for this explicit line in the html. However, there are use cases where we do want to separate the two steps. Sometimes we want full control over when we start looking for `<div>` tags inside the web page with `mermaid.initialize()` , for example when we think that all `<div>` tags may not have been loaded by the time `mermaid.min.js` runs.
2020-08-21 01:01:06 +08:00
