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# A Mermaid User-Guide for Beginners
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Creating diagrams and charts using mermaid code is simple.
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>The live editor is enough for most general uses of mermaid
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**Absolute beginners are recommended to view the Video [Tutorials ](./Tutorials.md ) on the Live Editor, to gain a better understanding of mermaid.**
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## Four ways of using mermaid:
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1. Using the mermaid [Live Editor ](https://mermaid-js.github.io/mermaid-live-editor/ ).
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- Learning the [Syntax ](./n00b-syntaxReference ) would be helpful.
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2. Using [mermaid plugins ](./integrations.md ) with programs you are familiar with.
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3. Hosting mermaid on a webpage, with an absolute link.
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4. Downloading mermaid and hosting it on your Web Page.
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**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 ).
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## 1. Using [The Live Editor](https://mermaidjs.github.io/mermaid-live-editor).
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In the `Code` section one can write or edit raw mermaid code, and instantly `Preview` the rendered result on the panel beside it.
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**Saving a Diagram:**
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You may choose any of the methods below, to save it
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**Configuration**
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*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.
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## 2. Using Mermaid Plugins:
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Using plug-ins you can generate mermaid diagrams from within popular applications, the same way that you would use the Live Editor. Here's a list of [Mermaid Plugins ](./integrations.md ).
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**This is covered in greater detail in the [Usage section ](usage.md )**
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## 3. Mermaid with Inline JavaScript
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This method can be used with any common web server. Apache, IIS, nginx, node express [...], you pick your favourite.
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You will need a text editting tool like Notepad++, to generate an html file. It is then deployed by a web browser (such as Firefox, Chrome, Safari, but not Internet Explorer).
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Just create an HTML file locally and open it using a desired browser.
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### Written in the html `<body>` section of the web page.
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When writing the html file, we give the web browser three instructions inside the html code:
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a. A reference for fetching the online mermaid renderer, which is written in Javascript.
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b. The mermaid code for the diagram we want to create.
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c. The `mermaid.initialize()` call to start the rendering process.
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## Requirements for mermaidAPI to render a diagram:
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**a. A reference to the external CDN in a `<script src>` tag, or a reference to mermaid.js as a separate file.:**
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```html
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< body >
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< script src = "https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.min.js" > < / script >
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< / body >
```
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**b. The embedded mermaid diagram definition inside a `<div class="mermaid">` :**
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```html
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< body >
Here is a mermaid diagram:
< div class = "mermaid" >
graph TD
A[Client] --> B[Load Balancer]
B --> C[Server01]
B --> D[Server02]
< / div >
< / body >
```
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**Notes**: every mermaid chart/graph/diagram definition, has to have separate `<div>` tags.
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**c. The `mermaid.initialize()` call.**
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`mermaid.initialize()` calls take all the definitions contained in `<div class="mermaid">` tags it can find in the html body and render. Example:
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```html
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< body >
< script > mermaid . initialize ( { startOnLoad : true } ) ; < / script >
< / body >
```
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**Notes**:
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Mermaid rendering is initalized with `mermaid.initialize()` .You can place `mermaid.initialize()` inside of `mermaid.min.js` for brevity. However, doing the opposite lets you control when it starts looking for `<div>` tags inside the web page with `mermaid.initialize()` , such as when you think that noy all `<div>` tags may not have been loaded when `mermaid.min.js` runs.
`startOnLoad` is one of the parameters that can be defined by `mermaid.initialize()`
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| Parameter | Description | Type | Values |
| --------- | --------------- | ------ | ---------------------------------------------------- |
|startOnLoad| Toggle for Rendering upon loading | Boolean | true, false |
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**Here is a full working example of the mermaidAPI being called through the CDN:**
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```html
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< html >
< body >
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< script src = "https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.min.js" > < / script >
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< script > mermaid . initialize ( { startOnLoad : true } ) ; < / script >
Here is one mermaid diagram:
< div class = "mermaid" >
graph TD
A[Client] --> B[Load Balancer]
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B --> C[Server1]
B --> D[Server2]
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< / div >
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And here is another:
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< div class = "mermaid" >
graph TD
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A[Client] -->|tcp_123| B(Load Balancer)
B -->|tcp_456| C[Server1]
B -->|tcp_456| D[Server2]
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< / div >
< / body >
< / html >
```
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**Another Option:**
In this example mermaid.js is referenced in `src` as a separate JavaScript file, in an example Path.
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```html
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< 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 >
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< script src = "The \Path \In \Your \Package \mermaid.js" ></ script >
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< script > mermaid . initialize ( { startOnLoad : true } ) ; < / script >
< / body >
< / html >
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```
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---
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## 4. Adding Mermaid as a dependency.
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1. install node v10 or 12, which would have npm
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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
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**Comments from Knut Sveidqvist, creator of mermaid:**
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- 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.
