TypeScript/AssemblyScript library for writing subgraph mappings to be deployed to The Graph.
For a detailed guide on how to create a subgraph, please see the Graph CLI docs.
One step of creating the subgraph is writing mappings that will process blockchain events and will write entities into the store. These mappings are written in TypeScript/AssemblyScript.
The graph-ts
library provides APIs to access the Graph Node store,
blockchain data, smart contracts, data on IPFS, cryptographic functions
and more. To use it, all you have to do is add a dependency on it:
npm install --dev @graphprotocol/graph-ts # NPM
yarn add --dev @graphprotocol/graph-ts # Yarn
After that, you can import the store
API and other features from
this library in your mappings. A few examples:
import { store, crypto, Entity } from '@graphprotocol/graph-ts'
// This is just an example event type generated by `graph-cli`
// from an Ethereum smart contract ABI
import { NameRegistered } from './abis/SomeContract'
function handleNameRegistered(event: NameRegistered) {
let name = event.params.name
let owner = event.params.owner
// Example use of a crypto function
let id = crypto.keccak256(name).toHex()
// Example use of the `Entity` class
let entity = new Entity()
entity.setString('id', id)
entity.setBytes('name', name)
entity.setAddress('owner', address)
// Example use of the store API
store.set('Name', id, entity)
}
We will document the functionality provided by graph-ts
soon. Until
then, please check the types and modules exported from the
library source code.
Copyright © 2018 Graph Protocol, Inc. and contributors.
The Graph TypeScript library is dual-licensed under the MIT license and the Apache License, Version 2.0.
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.