export:puml

Generate PlantUML diagrams from the active product’s feature model, database models, dependencies, and Docker topology.

Table of contents

1. Usage
2. Diagram modes
3. Output options
4. Examples
5. Feature model (default)
6. Class diagram (--classes)
   1. Example output
7. Dependency graph (--deps)
8. Deployment diagram (--deployment)
9. UVL resolution
10. Refinement mixins
11. Error reporting
12. Requirements
13. See also

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Usage

splent export:puml [OPTIONS]

Diagram modes

By default, export:puml generates a feature model diagram. Use flags to select other modes.

Flag	Diagram	What it shows
(none)	Feature model	Components with contracts (routes, models, services, hooks, env vars) + UVL constraints
--classes	UML class diagram	SQLAlchemy models with attributes, types, PKs, unique, nullable, methods, FK relationships with cardinality
--deps	Dependency graph	Clean feature nodes (colored by mandatory/optional) + requires arrows
--deployment	Docker deployment	Containers, images, ports, volumes, networks, and dependencies

Output options

Option	Description
--pdf	Also export as PDF (requires PlantUML + rsvg-convert)
--png	Also export as PNG
--svg	Also export as SVG
-o PATH	Custom output path (without extension)

Files are saved to <product>/exports/puml/ by default.

Examples

# Feature model (default)
splent export:puml

# Class diagram as PDF
splent export:puml --classes --pdf

# Dependency graph as PNG
splent export:puml --deps --png

# Docker deployment as SVG
splent export:puml --deployment --svg

# All formats at once
splent export:puml --classes --pdf --png --svg

# Custom output path
splent export:puml --classes -o docs/diagrams/models --pdf

Feature model (default)

Generates a component diagram showing all features declared in pyproject.toml with the following details.

• Cardinality. Mandatory or optional (from UVL)
• Contract details. Routes, blueprints, models, services, hooks, docker, env vars (from [tool.splent.contract] in each feature’s pyproject.toml)
• Dependencies. requires arrows between features (from UVL constraints)

splent export:puml

The output is written to exports/puml/<product>.puml.

Class diagram (--classes)

Parses models.py from each feature and generates a UML class diagram with the following elements.

• Classes grouped by feature (as <<Feature>> packages)
• Attributes. Name, type (int, str, datetime, bool), stereotypes (<<PK>>, <<unique>>), nullable (?)
• Methods. Public methods extracted from the model class
• Relationships. Foreign keys with cardinality ("1" -- "1" or "1" -- "*"), detected from db.ForeignKey and db.relationship (handles both quoted and unquoted target names)

splent export:puml --classes

The output is written to exports/puml/<product>_classes.puml.

Example output

package "auth" <<Feature>> {
  class User {
    + id : int <<PK>>
    + email : str? <<unique>>
    + password : str
    + created_at : datetime
    + active : bool
    ..
    + set_password()
    + check_password()
  }
}

package "profile" <<Feature>> {
  class UserProfile {
    + id : int <<PK>>
    + user_id : int <<unique>>
    + name : str
    + surname : str
  }
}

User "1" -- "1" UserProfile : profile

Dependency graph (--deps)

A clean, minimal diagram showing only feature nodes and dependency arrows. Features are color-coded.

• Dark blue (#2E86C1). Mandatory features
• Light blue (#AED6F1). Optional features

splent export:puml --deps

The output is written to exports/puml/<product>_deps.puml.

Deployment diagram (--deployment)

Reads all docker-compose.yml files (product + features + CLI) and generates a deployment diagram showing the following.

• Containers with appropriate shapes.
  • node for application containers
  • database for MariaDB/MySQL/PostgreSQL
  • storage for Redis
  • collections for mail services (MailHog)
• Ports. The host:container mappings
• Dependencies. depends_on relationships
• Named volumes. Persistent data volumes

splent export:puml --deployment

The output is written to exports/puml/<product>_deployment.puml.

UVL resolution

The command reads [tool.splent].spl from the product’s pyproject.toml and resolves that model the same way every other command does, from the working copy at splent_spl_<core>/, then from .splent_cache/spls/, then by downloading it with the DOI recorded under [tool.splent.spl_model].

If the product names no SPL, it falls back to the legacy [tool.splent.uvl].file configuration.

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Refinement mixins

When generating class diagrams (--classes), features that declare [tool.splent.refinement].extends.models in their pyproject.toml are handled specially. Mixin classes (classes defined without explicit base classes) are detected and their attributes and methods are merged into the target model in the diagram. This means the class diagram reflects the fully composed model, not the raw source files.

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Error reporting

When PlantUML fails to render a diagram, the actual PlantUML error output (stderr and stdout) is displayed directly, making it easier to diagnose syntax issues in the generated .puml file.

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Requirements

• PlantUML. Required for --pdf, --png, --svg rendering. Installed in the CLI Docker container.
• rsvg-convert. Required for PDF/PNG conversion from SVG. Part of librsvg2-bin in the CLI container.
• UVL file. Must be configured via [tool.splent].spl (SPL catalog, preferred) or [tool.splent.uvl].file (legacy) in the product’s pyproject.toml.
• Feature contracts. For full detail in the feature model, features should have [tool.splent.contract] in their pyproject.toml (auto-generated by feature:release).

See also

• product:validate. Validate the UVL model and check for conflicts between features
• feature:contract. Infer and write feature contracts