# Mermaid

Mermaid is a diagramming and charting tool that can be defined inside Markdown code blocks.

# Component syntax

With a similar syntax to code blocks, creating a Mermaid diagram requires a ``` code fence with the inclusion of the mermaid specifier.

Sample Mermaid diagram
```mermaid
graph LR
    A[Hard edge] -->|Link text| B(Round edge)
    B --> C{Decision}
    C -->|One| D[Result one]
    C -->|Two| E[Result two]
```
graph LR
    A[Hard edge] -->|Link text| B(Round edge)
    B --> C{Decision}
    C -->|One| D[Result one]
    C -->|Two| E[Result two]

# Directives

Mermaid directives can be configured using the recommended %%{init: { }}%% syntax as the first line just inside the ```mermaid block.

From the Mermaid docs:

Directives gives a diagram author the capability to alter the appearance of a diagram before rendering by changing the applied configuration.

All Mermaid directives are supported by Retype.

The following sample demonstrates applying a theme to the diagram:

```mermaid
%%{init: { 'theme': 'forest' }}%%
graph LR
    A[Hard edge] -->|Link text| B(Round edge)
    B --> C{Decision}
    C -->|One| D[Result one]
    C -->|Two| E[Result two]
```
%%{init: { 'logLevel': 'debug', 'theme': 'forest' }}%%
graph LR
    A[Hard edge] -->|Link text| B(Round edge)
    B --> C{Decision}
    C -->|One| D[Result one]
    C -->|Two| E[Result two]

# Syntax highlighting block

In order to draw a mermaid code block with syntax highlighting instead of rendering the contents, please use the mermaid-js block syntax specifier.

```mermaid-js
%%{init: { 'theme': 'forest' }}%%
graph LR
    A[Hard edge] -->|Link text| B(Round edge)
    B --> C{Decision}
    C -->|One| D[Result one]
    C -->|Two| E[Result two]
```
%%{init: { 'logLevel': 'debug', 'theme': 'forest' }}%%
graph LR
    A[Hard edge] -->|Link text| B(Round edge)
    B --> C{Decision}
    C -->|One| D[Result one]
    C -->|Two| E[Result two]

# Diagram types

# Flowchart

More details in Mermaid docs.

```mermaid
graph TD;
    A-->B;
    A-->C;
    B-->D;
    C-->D;
```
graph TD;
    A-->B;
    A-->C;
    B-->D;
    C-->D;

# Sequence diagram

More details in Mermaid docs.

```mermaid
sequenceDiagram
    participant Alice
    participant Bob
    Alice->>John: Hello John, how are you?
    loop Healthcheck
        John->>John: Fight against hypochondria
    end
    Note right of John: Rational thoughts <br/>prevail!
    John-->>Alice: Great!
    John->>Bob: How about you?
    Bob-->>John: Jolly good!
```
sequenceDiagram
    participant Alice
    participant Bob
    Alice->>John: Hello John, how are you?
    loop Healthcheck
        John->>John: Fight against hypochondria
    end
    Note right of John: Rational thoughts <br/>prevail!
    John-->>Alice: Great!
    John->>Bob: How about you?
    Bob-->>John: Jolly good!

# Gantt diagram

More details in Mermaid docs.

```mermaid
gantt
dateFormat  YYYY-MM-DD
title Adding GANTT diagram to mermaid
excludes weekdays 2014-01-10

section A section
Completed task            :done,    des1, 2014-01-06,2014-01-08
Active task               :active,  des2, 2014-01-09, 3d
Future task               :         des3, after des2, 5d
Future task2              :         des4, after des3, 5d
```
gantt
dateFormat  YYYY-MM-DD
title Adding GANTT diagram to mermaid
excludes weekdays 2014-01-10

section A section
Completed task            :done,    des1, 2014-01-06,2014-01-08
Active task               :active,  des2, 2014-01-09, 3d
Future task               :         des3, after des2, 5d
Future task2              :         des4, after des3, 5d

# Class diagram

More details in Mermaid docs.

```mermaid
classDiagram
Class01 <|-- AveryLongClass : Cool
Class03 *-- Class04
Class05 o-- Class06
Class07 .. Class08
Class09 --> C2 : Where am i?
Class09 --* C3
Class09 --|> Class07
Class07 : equals()
Class07 : Object[] elementData
Class01 : size()
Class01 : int chimp
Class01 : int gorilla
Class08 <--> C2: Cool label
```
classDiagram
Class01 <|-- AveryLongClass : Cool
Class03 *-- Class04
Class05 o-- Class06
Class07 .. Class08
Class09 --> C2 : Where am i?
Class09 --* C3
Class09 --|> Class07
Class07 : equals()
Class07 : Object[] elementData
Class01 : size()
Class01 : int chimp
Class01 : int gorilla
Class08 <--> C2: Cool label

# Entity Relationship

More details in Mermaid docs.

```mermaid
erDiagram
    CUSTOMER ||--o{ ORDER : places
    ORDER ||--|{ LINE-ITEM : contains
    CUSTOMER }|..|{ DELIVERY-ADDRESS : uses
```
erDiagram
    CUSTOMER ||--o{ ORDER : places
    ORDER ||--|{ LINE-ITEM : contains
    CUSTOMER }|..|{ DELIVERY-ADDRESS : uses

# User Journey

More details in Mermaid docs.

```mermaid
journey
    title My working day
    section Go to work
      Make tea: 5: Me
      Go upstairs: 3: Me
      Do work: 1: Me, Cat
    section Go home
      Go downstairs: 5: Me
      Sit down: 5: Me
```
journey
    title My working day
    section Go to work
      Make tea: 5: Me
      Go upstairs: 3: Me
      Do work: 1: Me, Cat
    section Go home
      Go downstairs: 5: Me
      Sit down: 5: Me

🧜‍♀️ Mermaid website
https://mermaid-js.github.io/mermaid/