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Data writers
Data writers are callback functions that Checkpoint invokes when the event of a contract is discovered at a particular block.
/**
* Callback function invoked by checkpoint when a contract event
* is encountered. A writer function should use the `mysql`
* object to write to the database entities based on the require logic.
*
* For example, if a graphql Entity is defined in the schema:
*
* ```graphql
* type Vote {
* id: ID!
* voter: String!
* }
* ```
*
* Then you can insert into the entity into the database like:
* ```typescript
* await args.mysql.queryAsync('INSERT INTO votes VALUES(?, ?);', ['voteId', 'voters-address']);
* ```
*
* Note, Graphql Entity names are lowercased with an 's' suffix when
* interacting with them in the database.
*e
*/
type CheckpointWriter = (args: {
tx: Transaction;
block: FullBlock;
event?: Event;
source: ContractSourceConfig;
mysql: AsyncMySqlPool;
instance: Checkpoint;
}) => Promise<void>;
/**
* Object map of events to CheckpointWriters.
*
* The CheckpointWriter function will be invoked when an
* event matching a key is found.
*
*/
interface CheckpointWriters {
[event: string]: CheckpointWriter;
}
Last modified 1yr ago