Cannot find smart contracts from NPM modules (e.g. @openzeppelin/contracts) when truffle-plugin-verify is installed globally

Hello, whenever i try to verify my ERC721 Contract I get the error message: “Cannot find module ‘@openzeppelin/contracts/GSN/Context.sol’”.

I am using the openzeppelin library (installed via npm install).

My SmartContract starts like this:

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/ownership/Ownable.sol";

contract ChallengeManager is LockFactory, ERC721, Ownable {
...

The ERC721 Contract has a dependency to the requested “Context.sol” Contract.

I also tried to import “@openzeppelin/contracts/GSN/Context.sol” on my ChallengeManager Contract, but i still get the same Error.

[emilyJLin95]

Well, I just followed @script-money 's suggestion and copied all the files into the contracts directory

I wonder if there’s a way that we don’t have to do that and verify will recognize files that live in node_modules?

[dherbst]

I ran into this issue as well, truffle compile worked ok, and migrate worked as well. But when I tried test the openzeppelin artifact files couldn’t be found by the resolver.

I noticed the openzeppelin contracts were not listed in the compilation logs for test

Then I did truffle test --compile-all and that fixed it. Subsequent runs of truffle test without the --compile-all flag work as well now.

Dropping this here in hopes this helps someone get past this quicker than I did.