<!DOCTYPE html><html lang="en"><head><meta charSet="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge"/><title>Client API Docs · Apache Heron</title><meta name="viewport" content="width=device-width"/><meta name="generator" content="Docusaurus"/><meta name="description" content="&lt;!--"/><meta name="docsearch:version" content="0.20.1-incubating"/><meta name="docsearch:language" content="en"/><meta property="og:title" content="Client API Docs · Apache Heron"/><meta property="og:type" content="website"/><meta property="og:url" content="https://heron.apache.org/"/><meta property="og:description" content="&lt;!--"/><meta property="og:image" content="https://heron.apache.org/img/undraw_online.svg"/><meta name="twitter:card" content="summary"/><meta name="twitter:image" content="https://heron.apache.org/img/undraw_tweetstorm.svg"/><link rel="shortcut icon" href="/img/favicon-32x32.png"/><link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/default.min.css"/><link rel="alternate" type="application/atom+xml" href="https://heron.apache.org/blog/atom.xml" title="Apache Heron Blog ATOM Feed"/><link rel="alternate" type="application/rss+xml" href="https://heron.apache.org/blog/feed.xml" title="Apache Heron Blog RSS Feed"/><script>
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href="/docs/0.20.1-incubating/getting-started-local-single-node">Local (Single Node)</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/getting-started-migrate-storm-topologies">Migrate Storm Topologies</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/getting-started-troubleshooting-guide">Troubleshooting Guide</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Deployment</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/deployment-overview">Deployment Overiew</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/deployment-configuration">Configuration</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/deployment-api-server">The Heron API Server</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Topology Development APIs</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/topology-development-streamlet-api">The Heron Streamlet API for Java</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/topology-development-eco-api">The ECO API for Java</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/topology-development-topology-api-java">The Heron Topology API for Java</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/topology-development-topology-api-python">The Heron Topology API for Python</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/topology-development-streamlet-scala">The Heron Streamlet API for Scala</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Client API Docs</h3><ul class=""><li class="navListItem navListItemActive"><a class="navItem" href="/docs/0.20.1-incubating/client-api-docs-overview">Client API Docs</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Guides</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/guides-effectively-once-java-topologies">Effectively Once Java Topologies</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/guides-data-model">Heron Data Model</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/guides-tuple-serialization">Tuple Serialization</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/guides-ui-guide">Heron UI Guide</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/guides-topology-tuning">Topology Tuning Guide</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/guides-packing-algorithms">Packing Algorithms</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/guides-simulator-mode">Simulator Mode</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/guides-troubeshooting-guide">Topology Troubleshooting Guide</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Heron Concepts</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/heron-design-goals">Heron Design Goals</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/heron-topology-concepts">Heron Topologies</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/heron-streamlet-concepts">Heron Streamlets</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/heron-architecture">Heron Architecture</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/heron-delivery-semantics">Heron Delivery Semantics</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">State Managers</h3><ul class=""><li class="navListItem"><a class="navItem" 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href="/docs/0.20.1-incubating/schedulers-k8s-by-hand">Kubernetes by hand</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/schedulers-k8s-with-helm">Kubernetes with Helm</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/schedulers-aurora-cluster">Aurora Cluster</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/schedulers-aurora-local">Aurora Locally</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/schedulers-local">Local Cluster</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/schedulers-nomad">Nomad</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/schedulers-mesos-local-mac">Mesos Cluster Locally</a></li><li class="navListItem"><a class="navItem" href="/docs/0.20.1-incubating/schedulers-slurm">Slurm Cluster</a></li><li class="navListItem"><a class="navItem" 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<p>You can view Pydocs <a href="http://heron.apache.org/api/python">here</a></p>
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