2.6. UML Sequence Diagram

• https://mermaid-js.github.io/mermaid/#/sequenceDiagram

2.6.1. Connections

• -> - Solid line without arrow

• --> - Dotted line without arrow

• ->> - Solid line with arrowhead

• -->> - Dotted line with arrowhead

• -x - Solid line with a cross at the end (async)

• --x - Dotted line with a cross at the end (async)

2.6.2. Conversation

```mermaid
sequenceDiagram

    participant Alice
    participant Bob

    Alice ->> Bob: Hello, how are you?
    Bob -->> Alice: Great!
```

2.6.3. Nested

```mermaid
sequenceDiagram

    participant Client
    participant Server
    participant Database

    activate Client
    Client ->> +Server: HTTP Request
    Server ->> +Database: SQL Query
    Database -->> -Server: Result
    Server -->> -Client: HTTP Response
    deactivate Client
```

2.6.4. Async

```mermaid
sequenceDiagram

participant Client
participant Server
participant Database

activate Client

Client -x +Server: HTTP Request
Client -x Server: HTTP Request
Server ->> +Database: SQL Query
Client -x Server: HTTP Request
Client -x Server: HTTP Request
Client -x Server: HTTP Request

Database -->> -Server: Result

Server --x -Client: HTTP Response

deactivate Client
```

2.6.5. Rationale