Ballerina API Documentation
Complete API documentation for all Ballerina standard library modules and extended modules is published on Ballerina Central. This page provides a categorized index of the most important modules used in integration development.
Standard library modules
Network - protocol modules
| Module | Description | API Docs |
|---|
ballerina/http | HTTP client and service with HTTP/1.1 and HTTP/2 support | API Docs |
ballerina/grpc | gRPC client and service support | API Docs |
ballerina/graphql | GraphQL service and client support | API Docs |
ballerina/websocket | WebSocket client and service support | API Docs |
ballerina/websub | WebSub hub, publisher, and subscriber | API Docs |
ballerina/websubhub | WebSub hub implementation | API Docs |
ballerina/tcp | TCP client and listener | API Docs |
ballerina/udp | UDP client and listener | API Docs |
ballerina/ftp | FTP client and listener | API Docs |
ballerina/email | SMTP, POP3, and IMAP email support | API Docs |
Network - messaging modules
| Module | Description | API Docs |
|---|
ballerinax/kafka | Apache Kafka producer and consumer | API Docs |
ballerinax/rabbitmq | RabbitMQ client and listener | API Docs |
ballerinax/nats | NATS client and listener | API Docs |
ballerinax/stan | NATS Streaming (STAN) client | API Docs |
ballerinax/java.jms | JMS client support | API Docs |
ballerinax/mqtt | MQTT client and listener | API Docs |
ballerinax/asb | Azure Service Bus client | API Docs |
Database modules
| Module | Description | API Docs |
|---|
ballerina/sql | Generic SQL client abstraction | API Docs |
ballerinax/mysql | MySQL database client | API Docs |
ballerinax/postgresql | PostgreSQL database client | API Docs |
ballerinax/mssql | Microsoft SQL Server client | API Docs |
ballerinax/oracledb | Oracle Database client | API Docs |
ballerina/persist | Data persistence layer | API Docs |
Data handling modules
| Module | Description | API Docs |
|---|
ballerina/io | File and stream I/O operations | API Docs |
ballerina/xmldata | XML data processing utilities | API Docs |
ballerina/constraint | Data validation constraints | API Docs |
ballerina/regex | Regular expression support | API Docs |
ballerina/mime | MIME type handling | API Docs |
ballerina/url | URL encoding and decoding | API Docs |
ballerina/data.jsondata | JSON data processing | API Docs |
ballerina/data.xmldata | XML data binding | API Docs |
ballerina/data.csv | CSV data processing | API Docs |
ballerinax/health.hl7v2 | HL7 v2 message processing | API Docs |
ballerinax/health.fhir.r4 | FHIR R4 resource types | API Docs |
Security modules
| Module | Description | API Docs |
|---|
ballerina/auth | Authentication framework | API Docs |
ballerina/jwt | JWT token handling | API Docs |
ballerina/oauth2 | OAuth 2.0 client support | API Docs |
ballerina/crypto | Cryptographic operations | API Docs |
Utility modules
| Module | Description | API Docs |
|---|
ballerina/log | Logging framework | API Docs |
ballerina/time | Date, time, and timezone operations | API Docs |
ballerina/uuid | UUID generation | API Docs |
ballerina/cache | In-memory caching | API Docs |
ballerina/task | Task scheduling (cron, timers) | API Docs |
ballerina/file | File system operations | API Docs |
ballerina/os | Operating system utilities | API Docs |
ballerina/lang.runtime | Runtime management | API Docs |
Observability modules
| Module | Description | API Docs |
|---|
ballerina/observe | Observability and tracing | API Docs |
ballerinax/prometheus | Prometheus metrics | API Docs |
ballerinax/jaeger | Jaeger distributed tracing | API Docs |
Cloud and SaaS connector modules
| Module | Description | API Docs |
|---|
ballerinax/salesforce | Salesforce CRM client | API Docs |
ballerinax/github | GitHub API client | API Docs |
ballerinax/googleapis.sheets | Google Sheets client | API Docs |
ballerinax/googleapis.gmail | Gmail client | API Docs |
ballerinax/slack | Slack messaging client | API Docs |
ballerinax/twilio | Twilio messaging and voice | API Docs |
ballerinax/aws.s3 | AWS S3 object storage | API Docs |
ballerinax/aws.sqs | AWS SQS messaging | API Docs |
ballerinax/azure.functions | Azure Functions integration | API Docs |
AI and LLM modules
| Module | Description | API Docs |
|---|
ballerinax/ai.agent | AI agent framework | API Docs |
ballerinax/openai.chat | OpenAI Chat API client | API Docs |
ballerinax/openai.embeddings | OpenAI Embeddings API client | API Docs |
ballerinax/azure.openai | Azure OpenAI client | API Docs |
Browsing API docs
On Ballerina central
- Go to central.ballerina.io
- Use the search bar to find a module by name or keyword
- Filter by organization (
ballerina for standard library, ballerinax for extended modules)
- Select a module to view its API documentation, including types, functions, classes, and examples
In VS code
The WSO2 Integrator VS Code extension provides inline API documentation:
- Hover over a module import to see the module description
- Use
Ctrl+Click (or Cmd+Click on macOS) on a function or type to navigate to its definition
- Use the command palette (
Ctrl+Shift+P) and search for "Ballerina: Show API Docs"
See also