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![logo](site2/website/static/img/pulsar.svg)

Pulsar is a distributed pub-sub messaging platform with a very
flexible messaging model and an intuitive client API.

Learn more about Pulsar at https://pulsar.apache.org

## Main features

* Horizontally scalable (Millions of independent topics and millions
  of messages published per second)
* Strong ordering and consistency guarantees
* Low latency durable storage
* Topic and queue semantics
* Load balancer
* Designed for being deployed as a hosted service:
  * Multi-tenant
  * Authentication
  * Authorization
  * Quotas
  * Support mixing very different workloads
  * Optional hardware isolation
* Keeps track of consumer cursor position
* REST API for provisioning, admin and stats
* Geo replication
* Transparent handling of partitioned topics
* Transparent batching of messages

## Repositories

This repository is the main repository of Apache Pulsar. Pulsar PMC also maintains other repositories for
components in the Pulsar ecosystem, including connectors, adapters, and other language clients.

- [Pulsar Core](https://github.com/apache/pulsar)

### Helm Chart

- [Pulsar Helm Chart](https://github.com/apache/pulsar-helm-chart)

### Ecosystem

- [Pulsar Adapters](https://github.com/apache/pulsar-adapters)
- [Pulsar Connectors](https://github.com/apache/pulsar-connectors)
- [Pulsar SQL (Pulsar Presto Connector)](https://github.com/apache/pulsar-presto)

### Clients

- [.NET/C# Client](https://github.com/apache/pulsar-dotpulsar)
- [Go Client](https://github.com/apache/pulsar-client-go)
- [NodeJS Client](https://github.com/apache/pulsar-client-node)
- [Ruby Client](https://github.com/apache/pulsar-client-ruby)

### Dashboard & Management Tools

- [Pulsar Manager](https://github.com/apache/pulsar-manager)

### Documentation

- [Pulsar Translation](https://github.com/apache/pulsar-translation)

### CI/CD

- [Pulsar CI](https://github.com/apache/pulsar-test-infra)

## Build Pulsar

Requirements:
 * Java 8 JDK (for building Pulsar)
   * When building Pulsar on a higher version (higher than Java 8), the resulting artifacts are not compatible with Java 8 runtime because of some issues, such as [issue 8445](https://github.com/apache/pulsar/issues/8445).
 * Maven 3.6.1+

Compile and install:

```bash
$ mvn install -DskipTests
```

## Minimal build (This skips most of external connectors and tiered storage handlers)
```
mvn install -Pcore-modules
```

Run Unit Tests:

```bash
$ mvn test
```

Run Individual Unit Test:

```bash
$ cd module-name (e.g: pulsar-client)
$ mvn test -Dtest=unit-test-name (e.g: ConsumerBuilderImplTest)
```

Run Selected Test packages:

```bash
$ cd module-name (e.g: pulsar-broker)
$ mvn test -pl module-name -Dinclude=org/apache/pulsar/**/*.java
```

Start standalone Pulsar service:

```bash
$ bin/pulsar standalone
```

Check https://pulsar.apache.org for documentation and examples.

## Setting up your IDE

Apache Pulsar is using [lombok](https://projectlombok.org/) so you have to ensure your IDE setup with
required plugins.

### Intellij

#### Configure annotation processing in IntelliJ

1. Open Annotation Processors Settings dialog box by going to
   `Settings -> Build, Execution, Deployment -> Compiler -> Annotation Processors`.

2. Select the following buttons:
   1. "Enable annotation processing"
   2. "Obtain processors from project classpath"
   3. "Store generated sources relative to: Module content root"

3. Set the generated source directories to be equal to the Maven directories:
   1. Set "Production sources directory:" to "target/generated-sources/annotations".
   2. Set "Test sources directory:" to "target/generated-test-sources/test-annotations".

4. Click "OK".

5. Install the lombok plugin in intellij.

#### Further configuration in IntelliJ 

* When working on the Pulsar core modules in IntelliJ, reduce the number of active projects in IntelliJ to speed up IDE actions and reduce unrelated IDE warnings.
  * In IntelliJ's Maven UI's tree view under "Profiles"
    * Activate "core-modules" Maven profile
    * De-activate "main" Maven profile
    * Run the "Reload All Maven Projects" action from the Maven UI toolbar. You can also find the action by the name in the IntelliJ "Search Everywhere" window that gets activated by pressing the **Shift** key twice.

* Run the "Generate Sources and Update Folders For All Projects" action from the Maven UI toolbar. You can also find the action by the name in the IntelliJ "Search Everywhere" window that gets activated by pressing the **Shift** key twice. Running the action takes about 10 minutes for all projects. This is faster when the "core-modules" profile is the only active profile.


#### IntelliJ usage tips

* In the case of compilation errors with missing Protobuf classes, ensure to run the "Generate Sources and Update Folders For All Projects" action.

* All of the Pulsar source code doesn't compile properly in IntelliJ and there are compilation errors.
  * Use the "core-modules" profile if working on the Pulsar core modules since the source code for those modules can be compiled in IntelliJ.
  * Sometimes it might help to mark a specific project ignored in IntelliJ Maven UI by right-clicking the project name and select **Ignore Projects** from the menu.
  * Currently, it is not always possible to run unit tests directly from the IDE because of the compilation issues. As a workaround, individual test classes can be run by using the `mvn test -Dtest=TestClassName` command.

### Eclipse

Follow the instructions [here](https://howtodoinjava.com/automation/lombok-eclipse-installation-examples/)
to configure your Eclipse setup.

## Build Pulsar docs

Refer to the docs [README](site2/README.md).

## Contact

##### Mailing lists

| Name                                                                          | Scope                           |                                                                 |                                                                     |                                                                              |
|:------------------------------------------------------------------------------|:--------------------------------|:----------------------------------------------------------------|:--------------------------------------------------------------------|:-----------------------------------------------------------------------------|
| [users@pulsar.apache.org](mailto:users@pulsar.apache.org) | User-related discussions        | [Subscribe](mailto:users-subscribe@pulsar.apache.org) | [Unsubscribe](mailto:users-unsubscribe@pulsar.apache.org) | [Archives](http://mail-archives.apache.org/mod_mbox/pulsar-users/) |
| [dev@pulsar.apache.org](mailto:dev@pulsar.apache.org)     | Development-related discussions | [Subscribe](mailto:dev-subscribe@pulsar.apache.org)   | [Unsubscribe](mailto:dev-unsubscribe@pulsar.apache.org)   | [Archives](http://mail-archives.apache.org/mod_mbox/pulsar-dev/)   |

##### Slack

Pulsar slack channel at https://apache-pulsar.slack.com/

You can self-register at https://apache-pulsar.herokuapp.com/

## License

Licensed under the Apache License, Version 2.0: http://www.apache.org/licenses/LICENSE-2.0

## Crypto Notice

This distribution includes cryptographic software. The country in which you currently reside may have restrictions on the import, possession, use, and/or re-export to another country, of encryption software. BEFORE using any encryption software, please check your country's laws, regulations and policies concerning the import, possession, or use, and re-export of encryption software, to see if this is permitted. See <http://www.wassenaar.org/> for more information.

The U.S. Government Department of Commerce, Bureau of Industry and Security (BIS), has classified this software as Export Commodity Control Number (ECCN) 5D002.C.1, which includes information security software using or performing cryptographic functions with asymmetric algorithms. The form and manner of this Apache Software Foundation distribution makes it eligible for export under the License Exception ENC Technology Software Unrestricted (TSU) exception (see the BIS Export Administration Regulations, Section 740.13) for both object code and source code.

The following provides more details on the included cryptographic software: Pulsar uses the SSL library from Bouncy Castle written by http://www.bouncycastle.org.