Namespaces Management

Organize your topics with namespaces in Danube.

Overview

Namespaces provide logical isolation for topics in your Danube cluster. Use namespaces to:

• Organize topics by application, team, or environment
• Apply policies at the namespace level
• Control access and resource allocation
• Separate production, staging, and development workloads

Commands

List Topics in a Namespace

View all topics within a specific namespace.

danube-admin-cli namespaces topics <NAMESPACE>

Basic Usage:

danube-admin-cli namespaces topics default

Output Formats:

# Plain text (default)
danube-admin-cli namespaces topics default

# JSON format - for automation
danube-admin-cli namespaces topics default --output json

Example Output (Plain Text):

Topics in namespace 'default':
  /default/user-events
  /default/payment-logs
  /default/analytics

Example Output (JSON):

[
  "/default/user-events",
  "/default/payment-logs",
  "/default/analytics"
]

---

View Namespace Policies

Get the policies configured for a namespace.

danube-admin-cli namespaces policies <NAMESPACE>

Basic Usage:

danube-admin-cli namespaces policies default

Output Formats:

# Plain text (default) - pretty printed
danube-admin-cli namespaces policies default

# JSON format
danube-admin-cli namespaces policies default --output json

Example Output (Plain Text):

Policies for namespace 'default':
{
  "max_topics_per_namespace": 1000,
  "max_producers_per_topic": 100,
  "max_consumers_per_topic": 100,
  "message_ttl_seconds": 604800,
  "retention_policy": "time_based"
}

Example Output (JSON):

{
  "max_topics_per_namespace": 1000,
  "max_producers_per_topic": 100,
  "max_consumers_per_topic": 100,
  "message_ttl_seconds": 604800,
  "retention_policy": "time_based"
}

Common Policies:

Policy	Description	Typical Values
max_topics_per_namespace	Maximum number of topics	100 - 10000
max_producers_per_topic	Maximum producers per topic	10 - 1000
max_consumers_per_topic	Maximum consumers per topic	10 - 1000
message_ttl_seconds	Message time-to-live	3600 (1h) - 604800 (7d)
retention_policy	How messages are retained	time_based, size_based

---

Create a Namespace

Create a new namespace in the cluster.

danube-admin-cli namespaces create <NAMESPACE>

Basic Usage:

# Create namespace
danube-admin-cli namespaces create production

Example Output:

✅ Namespace created: production

Naming Guidelines:

• Use lowercase letters and hyphens
• Keep names descriptive: production, staging, dev
• Avoid special characters
• Use consistent naming: team-app-env pattern

Examples:

# By environment
danube-admin-cli namespaces create production
danube-admin-cli namespaces create staging
danube-admin-cli namespaces create development

# By team
danube-admin-cli namespaces create analytics-team
danube-admin-cli namespaces create platform-team

# By application
danube-admin-cli namespaces create payment-service
danube-admin-cli namespaces create user-service

---

Delete a Namespace

Remove a namespace from the cluster.

danube-admin-cli namespaces delete <NAMESPACE>

Basic Usage:

danube-admin-cli namespaces delete old-namespace

Example Output:

✅ Namespace deleted: old-namespace

⚠️ Important Warnings:

1. All Topics Deleted: Deleting a namespace removes ALL topics within it
2. No Confirmation: This operation is immediate and irreversible
3. Active Connections: Connected producers/consumers will be disconnected
4. Data Loss: All messages in the namespace are permanently deleted

Safety Checklist:

# 1. List topics before deletion
danube-admin-cli namespaces topics my-namespace

# 2. Verify no critical topics
danube-admin-cli namespaces topics my-namespace --output json | grep -i critical

# 3. Check policies to understand impact
danube-admin-cli namespaces policies my-namespace

# 4. Only then delete
danube-admin-cli namespaces delete my-namespace

Common Workflows

1. Namespace Setup for New Application

# Create namespace
danube-admin-cli namespaces create payment-service

# Verify creation
danube-admin-cli brokers namespaces | grep payment-service

# Check default policies
danube-admin-cli namespaces policies payment-service

# Create topics in namespace
danube-admin-cli topics create /payment-service/transactions
danube-admin-cli topics create /payment-service/refunds
danube-admin-cli topics create /payment-service/notifications

2. Multi-Environment Setup

# Create environments
danube-admin-cli namespaces create production
danube-admin-cli namespaces create staging
danube-admin-cli namespaces create development

# List all namespaces
danube-admin-cli brokers namespaces

# Create same topics in each environment
for env in production staging development; do
  danube-admin-cli topics create /$env/user-events
  danube-admin-cli topics create /$env/order-events
done