PlantUML in Slidev
This skill covers using PlantUML for creating UML and technical diagrams in Slidev. PlantUML excels at creating standard UML diagrams with more detailed control than Mermaid.
When to Use This Skill
-
Creating standard UML diagrams
-
Complex sequence diagrams with detailed notation
-
Component and deployment diagrams
-
Use case diagrams
-
Activity diagrams with swimlanes
-
C4 architecture diagrams
Enabling PlantUML
PlantUML is supported via the plantuml code block:
@startuml
Alice -> Bob: Hello
Bob --> Alice: Hi!
@enduml
Sequence Diagrams
Basic Sequence
@startuml
participant User
participant "Web Server" as WS
participant Database as DB
User -> WS: HTTP Request
activate WS
WS -> DB: SQL Query
activate DB
DB --> WS: Result Set
deactivate DB
WS --> User: HTTP Response
deactivate WS
@enduml
Participant Types
@startuml
actor User
boundary "API Gateway" as API
control "Auth Service" as Auth
entity "User Entity" as UE
database "PostgreSQL" as DB
collections "Cache" as Cache
queue "Message Queue" as MQ
User -> API: Request
API -> Auth: Validate
Auth -> DB: Query
@enduml
Grouping and Alternatives
@startuml
actor User
participant Service
User -> Service: Login
alt Valid credentials
Service --> User: Success
else Invalid credentials
Service --> User: Error 401
end
group Optional
User -> Service: Refresh Token
Service --> User: New Token
end
loop Health Check
Service -> Service: Ping
end
@enduml
Notes
@startuml
participant Alice
participant Bob
Alice -> Bob: Request
note left: This is a note\non the left
Bob --> Alice: Response
note right: This is a note\non the right
note over Alice, Bob: Note over both participants
@enduml
Class Diagrams
Basic Class
@startuml
class User {
-id: Long
-email: String
-password: String
+login(): Boolean
+logout(): void
}
class Order {
-id: Long
-total: BigDecimal
+addItem(item: Item): void
+removeItem(id: Long): void
+checkout(): Boolean
}
User "1" --> "*" Order: places
@enduml
Interfaces and Abstract Classes
@startuml
interface Serializable {
+serialize(): String
}
abstract class BaseEntity {
#id: Long
#createdAt: DateTime
{abstract} +validate(): Boolean
}
class User extends BaseEntity implements Serializable {
-name: String
+serialize(): String
+validate(): Boolean
}
@enduml
Relationships
@startuml
class A
class B
class C
class D
class E
class F
A --|> B : extends
C ..|> D : implements
E --* F : composition
G --o H : aggregation
I --> J : association
K ..> L : dependency
@enduml
Packages
@startuml
package "Domain Layer" {
class User
class Order
}
package "Infrastructure Layer" {
class UserRepository
class OrderRepository
}
package "Application Layer" {
class UserService
class OrderService
}
UserService --> User
UserService --> UserRepository
@enduml
Use Case Diagrams
@startuml
left to right direction
actor Customer
actor Admin
rectangle "E-Commerce System" {
usecase "Browse Products" as UC1
usecase "Add to Cart" as UC2
usecase "Checkout" as UC3
usecase "Manage Products" as UC4
usecase "Process Orders" as UC5
}
Customer --> UC1
Customer --> UC2
Customer --> UC3
Admin --> UC4
Admin --> UC5
UC3 ..> UC2 : <<include>>
@enduml
Activity Diagrams
Basic Flow
@startuml
start
:Receive Order;
if (Payment Valid?) then (yes)
:Process Order;
:Ship Items;
else (no)
:Notify Customer;
:Cancel Order;
endif
stop
@enduml
Swimlanes
@startuml
|Customer|
start
:Submit Order;
|Sales|
:Review Order;
if (Valid?) then (yes)
|Warehouse|
:Pick Items;
:Pack Items;
|Shipping|
:Ship Package;
|Customer|
:Receive Package;
else (no)
|Sales|
:Reject Order;
|Customer|
:Receive Notification;
endif
stop
@enduml
Parallel Processing
@startuml
start
:Initialize;
fork
:Process A;
fork again
:Process B;
fork again
:Process C;
end fork
:Merge Results;
stop
@enduml
Component Diagrams
@startuml
package "Frontend" {
[React App] as Web
[Mobile App] as Mobile
}
package "Backend" {
[API Gateway]
[Auth Service]
[User Service]
[Order Service]
}
package "Data Layer" {
database "PostgreSQL" as DB
database "Redis" as Cache
queue "RabbitMQ" as MQ
}
Web --> [API Gateway]
Mobile --> [API Gateway]
[API Gateway] --> [Auth Service]
[API Gateway] --> [User Service]
[API Gateway] --> [Order Service]
[User Service] --> DB
[Order Service] --> DB
[Order Service] --> MQ
[Auth Service] --> Cache
@enduml
Deployment Diagrams
@startuml
node "AWS Cloud" {
node "VPC" {
node "Public Subnet" {
[Load Balancer] as LB
}
node "Private Subnet" {
node "ECS Cluster" {
[API Container] as API
[Worker Container] as Worker
}
}
node "Data Subnet" {
database "RDS PostgreSQL" as DB
database "ElastiCache Redis" as Cache
}
}
}
actor User
User --> LB
LB --> API
API --> DB
API --> Cache
Worker --> DB
@enduml
State Diagrams
@startuml
[*] --> Draft
Draft --> Submitted : submit()
Submitted --> UnderReview : startReview()
UnderReview --> Approved : approve()
UnderReview --> Rejected : reject()
Rejected --> Draft : revise()
Approved --> Published : publish()
Published --> [*]
Draft : entry / loadDraft()
Draft : exit / saveDraft()
state UnderReview {
[*] --> Reviewing
Reviewing --> WaitingForInfo : requestInfo()
WaitingForInfo --> Reviewing : infoProvided()
}
@enduml
Styling
Skinparams
@startuml
skinparam backgroundColor #f8fafc
skinparam roundCorner 10
skinparam shadowing false
skinparam class {
BackgroundColor #e0f2fe
BorderColor #0284c7
FontColor #0c4a6e
}
skinparam sequence {
ArrowColor #0284c7
LifeLineBorderColor #64748b
ParticipantBackgroundColor #e0f2fe
}
class User {
+name: String
}
@enduml
Themes
@startuml
!theme cerulean
class MyClass {
+attribute: String
}
@enduml
Available themes: cerulean , materia , minty , sandstone , sketchy-outline , and more.
C4 Model Diagrams
Context Diagram
@startuml
!include https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/master/C4_Context.puml
Person(user, "Customer", "A user of our system")
System(system, "E-Commerce", "Online shopping platform")
System_Ext(payment, "Payment Gateway", "Handles payments")
System_Ext(shipping, "Shipping Provider", "Delivers packages")
Rel(user, system, "Uses")
Rel(system, payment, "Processes payments via")
Rel(system, shipping, "Ships orders via")
@enduml
Container Diagram
@startuml
!include https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/master/C4_Container.puml
Person(user, "Customer")
System_Boundary(system, "E-Commerce Platform") {
Container(web, "Web App", "React", "User interface")
Container(api, "API", "Node.js", "Business logic")
ContainerDb(db, "Database", "PostgreSQL", "Stores data")
Container(queue, "Queue", "RabbitMQ", "Async processing")
}
Rel(user, web, "Uses")
Rel(web, api, "API calls")
Rel(api, db, "Reads/Writes")
Rel(api, queue, "Publishes")
@enduml
Configuration
setup/plantuml.ts
import { definePlantUmlSetup } from '@slidev/types'
export default definePlantUmlSetup(() => { return { // Server URL (default uses public server) server: 'https://www.plantuml.com/plantuml', } })
Mermaid vs PlantUML
Feature Mermaid PlantUML
Syntax Simpler More verbose
UML compliance Partial Full
Rendering Client-side Server-side
C4 diagrams No Yes
Swimlanes No Yes
Customization Limited Extensive
Best Practices
-
Use PlantUML for: Standard UML, C4, complex diagrams
-
Use Mermaid for: Simple flowcharts, quick visualizations
-
Add skinparams: Customize for your presentation theme
-
Keep diagrams focused: One concept per diagram
-
Use proper UML notation: Follow standards for clarity
Output Format
When creating PlantUML diagrams:
DIAGRAM TYPE: [sequence/class/component/etc.] PURPOSE: [What it illustrates]
@startuml
[skinparams if needed]
[diagram content]
@enduml
KEY ELEMENTS:
- [Element]: [What it represents]
NOTES:
- [Any additional context]