Lesson 15 : Subgraph mapping error

[NicolasMazzoleni]

Hello guys,

I am facing an issue here after running the mint-and-list script to the goerli testnet. Here are all the informations

1. The subgraph has been correctly deployed

2. After this, I executed following the course, this command in hardhat-nft-maretplace-fcc project
   yarn hardhat run scripts/mint-and-list.js --network goerli
   Everything went well in the Terminal, both Contracts are well deployed
   https://goerli.etherscan.io/address/0x69533f6bf3ba13b7527bacec0fc9fb817d88a9df
   https://goerli.etherscan.io/address/0x1034d9555bbf351a6e10997b6f3df7f66692b7a6

3. Went to the subgraph studio platform and saw this error below

Not sure exactly where this could come from, it's not very easy to understand it.
Here is the links of the repos:
https://github.com/NicolasMazzoleni/thegraph-nft-marketplace-fcc
https://github.com/NicolasMazzoleni/hardhat-nft-marketplace-fcc

Still trying to find the issue but if you have an idea that would be much appreciated.

Thank you for your help,
Nico

[0xpolarzero]

Hi @NicolasMazzoleni. These errors in the subgraph logs can sometimes be quite enigmatic.

In the code for handleItemListed in src/nft-marketplace.ts, it seems like there was an unexpected null entity. Which is weird because you made sure to load the activeItem, or create it if it doesn't exist.

Except that there is a little issue right here in your code, line 62:

 if (!activeItem) {
  new ActiveItem(getIdFromEventParams(event.params.tokenId, event.params.nft))
} 

See how the newly created ActiveItem is never assigned to the variable activeItem? I believe it's just a typo, as you did it correctly in the other functions.

Let me know if it works correctly after that.

[NicolasMazzoleni]

@0xpolarzero Thanks a lot didn't see that one.. Worked now ! Got the activeItems and itemListed objects in The Graph Studio Playground. Thanks a lot

[0xpolarzero]

@NicolasMazzoleni Amazing, glad it helped! Have fun!