Please find below my code snippet. Here credentialHash is not being set in the .then() call. Neither the "In then" or "Callback rejected" are being printed so I know that it is not running but I cant understand why. I've also included code for the setHash function in my smart contract.
let hash;
await ipfs.add(JSON.stringify(this.state.credential)).then((result, error) => {
hash = result.path;
if (error) {
console.error(error)
return;
}
// Store hash on blockchain
console.log("Hash before BC:" + hash);
this.state.contract.methods.setHash(hash).send({from: this.state.account}).then((resolve) => {
console.log("In then")
this.setState({credentialHash: hash});
}, (rejected) => {
console.log("Callback rejected");
});
console.log("After setting:" + this.state.credentialHash);
});function setHash(string memory _CredentialHash) public returns(string memory) { credentialHash = _CredentialHash; return _CredentialHash; }
The result returned from console.log(this.state.contract.methods.setHash(hash).send({from: this.state.account})) is :
Proxy {promise: Promise, eventEmitter: EventEmitter, resolve: ƒ, reject: ƒ}
[[Handler]]: Object
get: ƒ proxyHandler(target, name)
[[Prototype]]: Object
[[Target]]: PromiEvent
eventEmitter: EventEmitter
_events: Events
[[Prototype]]: Object
_eventsCount: 0
[[Prototype]]: Object
promise: Promise
[[Prototype]]: Promise
[[PromiseState]]: "pending"
[[PromiseResult]]: undefined
reject: ƒ ()
resolve: ƒ ()
[[Prototype]]: Object
[[IsRevoked]]: false
Try dropping the .then() syntax entirely and use only the async/await style. What does the code below give?
let hash, result;
try {
result = await ipfs.add(JSON.stringify(this.state.credential))
hash = result.path;
} catch (error) {
console.error(error)
return;
}
// Store hash on blockchain
console.log("Hash before BC:" + hash);
try {
await this.state.contract.methods.setHash(hash).send({
from: this.state.account
})
} catch(error) {
console.log("Callback rejected");
return
}
this.setState({
credentialHash: hash
});
console.log("After setting:" + this.state.credentialHash);
For anyone else with this issue, I finally found the answer. The default number of transactionConfirmationBlocks is 24 which takes a long time to complete. Setting this to 1 as below solved my issue.
this.setState({contract: new web3.eth.Contract(
credentialArtifact.abi,
deployedNetworkCred.address,
{transactionConfirmationBlocks: 1}
)});