plantuml-ascii

# Standard ASCII output
plantuml -txt diagram.puml
 
# Unicode-enhanced output (better looking)
plantuml -utxt diagram.puml
 
# Using JAR directly
java -jar plantuml.jar -txt diagram.puml
java -jar plantuml.jar -utxt diagram.puml

@startuml
actor User
participant "Web App" as App
database "Database" as DB
 
User -> App : Login Request
App -> DB : Validate Credentials
DB --> App : User Data
App --> User : Auth Token
@enduml

@startuml
class User {
  +id: int
  +name: string
  +email: string
  +login(): bool
}
 
class Order {
  +id: int
  +total: float
  +items: List
  +calculateTotal(): float
}
 
User "1" -- "*" Order : places
@enduml

@startuml
start
:Initialize;
if (Is Valid?) then (yes)
  :Process Data;
  :Save Result;
else (no)
  :Log Error;
  stop
endif
:Complete;
stop
@enduml

@startuml
[*] --> Idle
Idle --> Processing : start
Processing --> Success : complete
Processing --> Error : fail
Success --> [*]
Error --> Idle : retry
@enduml

@startuml
[Client] as client
[API Gateway] as gateway
[Service A] as svcA
[Service B] as svcB
[Database] as db
 
client --> gateway
gateway --> svcA
gateway --> svcB
svcA --> db
svcB --> db
@enduml

@startuml
actor "User" as user
actor "Admin" as admin
 
rectangle "System" {
  user -- (Login)
  user -- (View Profile)
  user -- (Update Settings)
  admin -- (Manage Users)
  admin -- (Configure System)
}
@enduml

@startuml
actor "User" as user
node "Load Balancer" as lb
node "Web Server 1" as ws1
node "Web Server 2" as ws2
database "Primary DB" as db1
database "Replica DB" as db2
 
user --> lb
lb --> ws1
lb --> ws2
ws1 --> db1
ws2 --> db1
db1 --> db2 : replicate
@enduml

# Specify output directory
plantuml -txt -o ./output diagram.puml
 
# Process all files in directory
plantuml -txt ./diagrams/
 
# Include dot files (hidden files)
plantuml -txt -includeDot diagrams/
 
# Verbose output
plantuml -txt -v diagram.puml
 
# Specify charset
plantuml -txt -charset UTF-8 diagram.puml

<target name="generate-ascii">
  <plantuml dir="./src" format="txt" />
</target>
 
<target name="generate-unicode-ascii">
  <plantuml dir="./src" format="utxt" />
</target>

     ,---.          ,---.
     |Bob|          |Alice|
     `---'          `---'
      |   hello      |
      |------------->|
      |              |
      |  Is it ok?   |
      |<-------------|
      |              |

┌─────┐        ┌─────┐
│ Bob │        │Alice│
└─────┘        └─────┘
  │   hello      │
  │─────────────>│
  │              │
  │  Is it ok?   │
  │<─────────────│
  │              │

# Create sequence diagram in ASCII
cat > seq.puml << 'EOF'
@startuml
Alice -> Bob: Request
Bob --> Alice: Response
@enduml
EOF
 
plantuml -txt seq.puml
cat seq.atxt
 
# Create with Unicode
plantuml -utxt seq.puml
cat seq.utxt