ethereum | Drupal Ethereum module | Cryptocurrency library

to test locally you need to make use of mocks which can simulate having an oracle network. Because you're working locally, a Chainlink node doesn't know about your local blockchain, so you can't actually do proper VRF requests. Note you can try deploy a local Chainlink node and a local blockchain and have them talk, but it isn't fully supported yet so you may get mixed results. Anyway, as per the hardhat starter kit that you linked, you can set the defaultNetwork to be 'hardhat' in the hardhat.config.js file, then when you deploy and run the integration tests (yarn test-integration), it will use mocks to mock up the VRF node, and to test the requesting of a random number. See the test here, and the mock contracts and linktoken get deployed here

it appears your env variables are not set correctly, and it looks like in this case it's your WEB3_INFURA_PROJECT_ID.

You can fix it by setting the variable in your .env file and adding dotenv: .env to your brownie-config.yaml.

brownie-config.yaml:

dotenv: .env .env:

export WEB3_INFURA_PROJECT_ID=YOUR_PROJECT_ID_HERE Remember to save these files.

Additionally, you should be on at least brownie version v1.14.6. You can find out what version you're on with:

brownie --version

I fixed this, I was passing constructor parameters of Portfolio to _PortfolioState, this won't update the values the next time. Instead of passing these values to _PortfolioState, I used widget.coin and widget.days to extract the data from the Portfolio class.

Thanks to this StackOverflow link: Passing Data to a Stateful Widget in Flutter

It appears 1.10.9-stable version has a problem and is returning a -rpc error. GETH 1.10.8-stable version works fine when running the geth command with --rpc

This is fixed in Brownie v1.18.1. However, you will need to install Python 3.9.10 in order to get the latest brownie. For this to work in a virtual environment you can't use venv. Here is a process that works for me:

• install virtualenv on your standard Python version
• download python 3.9.10 and install it without "add to path" into a dedicated directory e.g. $home/pythonversions
• in your project directory create a virtual environment like so

python -m virtualenv -p=""

• start your virtual environment e.g. home>..venv\Scripts\activate.ps1

• test if your python version is the desired one with python --version

• Now install Cython to avoid another error.

• Install nodeenv in order to install ganage

• Activate with nodeenv -p (for this step you will need PowerShell with admin rights)

• Install ganache with npm

• Install eth-brownie with pip check if you got the latest version with

brownie --version

There is no simple answer to this question, but I will give it a try.

It would be of course best if you can find a course that is using the version 0.8 of Solidity. That way, you can learn all the latest Solidity features that were introduced in the past couple of years. However, fact that the course us using version 0.8 should not be the only criteria. For example, it is also important that the course has good approach in teaching you the concepts of smart contracts and how is that realized on the Ethereum platform. I personally have learned Ethereum platform and Solidity using a course which uses outdated Solidity version. But the course itself was good, and has given me a good foundation. It was easy for me to then pick up the differences that were introduced in the later versions. However, note that I am an software engineer with over 10 years of experience, so that helps a lot.

With all that said, my suggestion would be the following. If you are an experienced developer, just go with any course that has good reviews, you can figure out the differences between the version without much issues. If you are however new to the world of software development, try finding a course that uses some more recent version, as you might struggle with some of the differences.

i had the same issue. i had this compiler setting:

You cannot delete an image from IPFS the way you interact with the database. (giving the IPNS of the content and user sends an http request to delete it).

When you upload your content, you pin it to a node. Now the thing is the node that your content is pinned should be unpinned. So if you have a control over that node, If you started your own node, you unpin it and then ipfs will garbage collect it.

https://docs.ipfs.io/concepts/persistence/#garbage-collection

But if an image has been added and copied to another node, any person with the fingerprint can find it again. So whoever controls that node should unpin it.

In order to interact with an ERC20 token, you have to create an instance of it from the desired contract. You would need to import ERC20 to your nfts contracts, and then create an ERC20 token instance pointing to your token. It would be something like this: