Initial commit

.gitignore

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+target/
+pom.xml.tag
+pom.xml.releaseBackup
+pom.xml.versionsBackup
+pom.xml.next
+release.properties
+dependency-reduced-pom.xml
+buildNumber.properties
+.mvn/timing.properties
+# https://github.com/takari/maven-wrapper#usage-without-binary-jar
+.mvn/wrapper/maven-wrapper.jar
+
+# Eclipse m2e generated files
+# Eclipse Core
+.project
+# JDT-specific (Eclipse Java Development Tools)
+.classpath
+
+# intellij
+.idea
+*.iml
+
+# vscode
+.vscode

ADOPTERS.md

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+# Adopters
+
+This is an alphabetical list of people and organizations who are using this
+project. If you'd like to be included here, please send a Pull Request that
+adds your information to this file.
+
+- [Pinterest](https://www.pinterest.com/)

CODE_OF_CONDUCT.md

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+# Code of Conduct
+
+At Pinterest, we work hard to ensure that our work environment is welcoming
+and inclusive to as many people as possible. We are committed to creating this
+environment for everyone involved in our open source projects as well. We
+welcome all participants regardless of ability, age, ethnicity, identified
+gender, religion (or lack there of), sexual orientation and socioeconomic
+status.
+
+This code of conduct details our expectations for upholding these values.
+
+## Good behavior
+
+We expect members of our community to exhibit good behavior including (but of
+course not limited to):
+
+- Using intentional and empathetic language.
+- Focusing on resolving instead of escalating conflict.
+- Providing constructive feedback.
+
+## Unacceptable behavior
+
+Some examples of unacceptable behavior (again, this is not an exhaustive
+list):
+
+- Harassment, publicly or in private.
+- Trolling.
+- Sexual advances (this isn’t the place for it).
+- Publishing other’s personal information.
+- Any behavior which would be deemed unacceptable in a professional environment.
+
+## Recourse
+
+If you are witness to or the target of unacceptable behavior, it should be
+reported to Pinterest at [email protected]. All reporters will
+be kept confidential and an appropriate response for each incident will be
+evaluated.
+
+If the maintainers do not uphold and enforce this code of conduct in
+good faith, community leadership will hold them accountable.

CONTRIBUTING.md

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+# Contributing
+
+First off, thanks for taking the time to contribute! This guide will answer
+some common questions about how this project works.
+
+While this is a Pinterest open source project, we welcome contributions from
+everyone. Regular outside contributors can become project maintainers.
+
+## Help
+
+If you're having trouble using this project, please start by reading the [`README.md`](README.md)
+and searching for solutions in the existing open and closed issues.
+
+## Security
+
+If you've found a security issue in one of our open source projects,
+please report it at [Bugcrowd](https://bugcrowd.com/pinterest); you may even
+make some money!
+
+## Code of Conduct
+
+Please be sure to read and understand our [`CODE_OF_CONDUCT.md`](CODE_OF_CONDUCT.md).
+We work hard to ensure that our projects are welcoming and inclusive to as many
+people as possible.
+
+## Reporting Issues
+
+If you have a bug report, please provide as much information as possible so that
+we can help you out:
+
+- Version of the project you're using.
+- Code (or even better whole projects) which reproduce the issue.
+- Steps which reproduce the issue.
+- Screenshots, GIFs or videos (if relavent).
+- Stack traces for crashes.
+- Any logs produced.
+
+## Making Changes
+
+1. Fork this repository to your own account
+2. Make your changes and verify that tests pass
+3. Commit your work and push to a new branch on your fork
+4. Submit a pull request
+5. Participate in the code review process by responding to feedback
+
+Once there is agreement that the code is in good shape, one of the project's
+maintainers will merge your contribution.
+
+To increase the chances that your pull request will be accepted:
+
+- Follow the coding style
+- Write tests for your changes
+- Write a good commit message
+
+## License
+
+By contributing to this project, you agree that your contributions will be
+licensed under its [license](LICENSE).

LICENSE

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README.md

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+# PubSub Client (PSC)
+
+PubSub Client (PSC) is a generic and extensible client library that allows applications to interact with different backend PubSub systems with a single unified interface. Designed with dev velocity, ease-of-adoption, and flexibility as guiding principles, and having been battle-tested at large scale, PSC is ready to handle production workloads from day one.
+
+## Highlights
+
+Some highlights of PSC include:
+- **Hiding PubSub complexities from application developers**: With out-of-the-box features such as optimized configurations and automated service endpoint discovery, application teams can focus on the application logic itself instead of spending precious time debugging client-server connectivity issues. At the same time, platform teams can fully control the clients and client versions that interact with their PubSub servers.
+
+- **Seamlessly switching between different PubSub systems**: With a singular, unified set of APIs for interacting with different PubSub systems, PSC provides the opportunity for client applications to seamlessly switch between PubSubs with zero code change.
+
+- **Automated error handling and remediation**: Built with reducing KTLO burden in mind, PSC is capable of automatically handling common errors and exceptions that occur in the client, all without causing disruption to the client application itself.
+
+- **Unified metrics**: PSC provides a unified set of metrics common to typical PubSub systems and tags them with useful information, allowing for human-friendly visibility into the status of the client
+
+- **Apache Flink support**: PSC comes out-of-the-box with the PSC-Flink connector, allowing [Apache Flink](https://github.com/apache/flink) data streaming jobs to leverage the benefits of PSC.
+
+## Current Status
+
+***PSC is currently under active development.***
+
+PSC currently supports [Apache Kafka](https://github.com/apache/kafka) and [MemQ](https://github.com/pinterest/memq) PubSub systems in Java, with support for more languages and PubSub systems coming soon.
+
+## Compatibility Matrix
+
+Please reference this compatibility matrix to determine which PSC version to adopt:
+
+|               | PSC 2.x  | PSC 3.x  |
+| ---           | ---      | ---      |
+| Apache Flink  | 1.11.1   | 1.15.1   |         
+| Apache Kafka  | 2.3.1    | 2.8.1    |
+| MemQ          | 0.2.20   | 0.2.20   |
+
+## Architecture
+![Image of PSC's Architecture](docs/images/psc-architecture.jpg)
+
+## Quick Start
+Detailed quick start instructions can be found [here](docs/quickstart.md).
+
+## Kafka Client to PSC Migration
+Please take a look at this [doc](/docs/nativekafkatopscmigration.md) for more information.
+
+## Blog
+Check out the original [PSC blog post](https://medium.com/pinterest-engineering/unified-pubsub-client-at-pinterest-397ccfaf508e) for more details and background!
+
+## Maintainers
+- Vahid Hashemian
+- Jeff Xiang
+- Jesus Zuniga
+
+## Contributors
+- Ambud Sharma
+- Shardul Jewalikar
+
+## License
+PubSub Client is distributed under Apache License, Version 2.0.