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NODE OPERATORS Overview Running a Chainlink Node Fulfilling Requests Run an Ethereum Client Performing System Maintenance Connecting to a Remote Database Configuration Variables Enabling HTTPS Connections Best Security and Operating Practices Best Practices for Nodes on AWS Miscellaneous
ORACLE JOBS Migrating to v2 Jobs Cron Direct Request Flux Monitor Keeper Off-chain Reporting Webhook HTTP Bridge JSON Parse CBOR Parse ETH ABI Decode ETH ABI Decode Log ETH ABI Encode ETH Call ETH Tx Multiply Divide Any Mean Median Mode Sum
v1 JSON JOBS [DEPRECATED] Job Specifications Core Adapters Initiators
EXTERNAL ADAPTERS Introduction External Adapters in Solidity Building External Adapters Bridges: Adding External Adapters to Nodes
EXTERNAL INITIATORS Introduction Building External Initiators Adding External Initiators to Nodes

Tasks

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What is a Task?

NOTE

This page refers to tasks in the latest version of Chainlink jobs (otherwise known as TOML, or v2 jobs). For documentation on the legacy job format, see v1 job specs.

A task is essentially the equivalent of the old adapters but more flexible. Tasks can be composed in arbitrary order into pipelines. Pipelines consist of one or more threads of execution where tasks are executed in a well-defined order.

Chainlink has a number of built-in tasks which are listed below. You can also create your own external adapters for tasks which are accessed through a bridge.

Shared attributes

All tasks share a few common attributes:

index: when a task has more than one input (or the pipeline overall needs to support more than one final output), and the ordering of the values matters, the index parameter can be used to specify that ordering.

data_1 [type="http" method="get" url="https://chain.link/eth_usd"       index=0]
data_2 [type="http" method="get" url="https://chain.link/eth_dominance" index=1]
multiword_abi_encode [type="eth_abi_encode" method="fulfill(uint256,uint256)"]

data_1 -> multiword_abi_encode
data_2 -> multiword_abi_encode

timeout: The maximum duration that the task is allowed to run before it is considered to be errored. Overrides the maxTaskDuration value in the job spec.