Conceptualizing Transactions vs Internal Transactions

[paulgs9988]

I was hoping someone might be able to help me with conceptualizing some things. I am at the part of the tutorial where I just created the "withdraw" function in my FundMe contract and we just went over the three ways to transfer eth (i.e. transfer, send, call). The tutorial structures this code, it seems, that if you withdraw, you just withdraw the contract's eth to itself. So I changed the withdraw function so it looks like this:

function withdraw(address withdrawAddress) public {
        // -TRANSFER:
        payable(withdrawAddress).transfer(address(this).balance);
}

In other words, I want to be able to pass an address to which to withdraw the funds as a variable in the withdraw function. I was expecting this to transfer the contract's amount to my address when I enter my address and click "withdraw" in Remix, but instead of having a transaction for the amount "IN" to my address on etherscan, it only shows up as an "internal transaction" on the separate tab.

I was viewing this whole thing as sort of: the contract exists as a separate "account" on the chain, and I can send eth as an "out" transaction to that contract, but then when I click "withdraw" I should be able to get an "in" transaction into my address account as that contract "account" is drained. Is this not correct? Can someone help me clarify?

Below is a screen shot that shows how these "withdrawals" are shown as "internal transactions" from the contract address to my metamask address

[krakxn]

Refer this for a better understanding: #1218

While it is okay for now payable(withdrawAddress).transfer(address(this).balance);, it is important to note that this is a very critical error—which you will comprehend in the future from self-learning and completion of the course—and should be avoided. Just remember this.

Now, try to answer by yourself—I believe the above is sufficient—and if not, do not worry, I am here.

[paulgs9988]

From some other research I've done, it seems that "transactions" are like "address to address" transactions, whereas "internal transactions" are ones that are governed by some sort of logic in a smart contract. Is this correct? Also, why doesn't the "Activity" section of Metamask seem to recognize these internal transactions? I tried the following:

I funded and created my contract using one address (Address1), then I withdrew the funds to a separate address (Address2). I received the funds from the contract to Address2; however, the metamask UI doesn't show this transaction in the "activity" tab. The new amount just appeared. In order to see this transaction on etherscan, I have to view the "internal transactions" tab as you can see here:

https://rinkeby.etherscan.io/address/0xA6D1A0b97eC9BDdBB08Cb0824ea342AB78712Fc2#internaltx

I hope this clarifies my question a bit more.

[krakxn]

Elaborate read on this: https://coinmarketcap.com/alexandria/glossary/internal-transaction

Briefly: Transactions to smart contracts are irreversible and trackable and are sent by EOAs (externally owned accounts), when they interact with smart contracts, they create byproducts or side-effects of some sort such as Internal Transactions. In other words, an internal transaction is the consequence of smart contract logic that is triggered by an external transaction. A single interaction with a smart contract can create hundreds and thousands of internal transactions. Transactions are changes to the state of the Ethereum chain, i.e. they write data to the chain rather than reading it.

[alymurtazamemon]

@paulgs9988 This part is ok, that you have created a parameter for passing the address for withdrawal, but there should be one thing more and that is onlyOnwer. Otherwise, anybody can call this function and withdraw the amount.

And for your rest of transaction thing went our my head, I read three times. So I cannot answer it right now, maybe you brief your question more so I can understand what you are trying to say.

[paulgs9988]

Yes, thanks. I'll try to break it down a bit more. This is the process I took:
-Fund the contract with 0.026 ETH from Address A(so the value in the contract on etherscan now reads 0.026)
-I use the withdraw function to withdraw the contract's balance (0.026) to Address B.
-Now Address B has the 0.026 ETH added to it as can be seen by viewing the balance on Etherscan or Metamask

HOWEVER:
-The Metamask UI DOES NOT recognize any transaction IN to Address B if I check the "Activity" section (as it would if I just sent 0.026 ETH from Address A to Address B)
-ALSO: If I view the information for Address B on etherscan, I don't see any record of the 0.026 ETH transaction into the account in the transactions section. I have to click on the "Internal Transactions" tab in order to see the transaction. ( https://rinkeby.etherscan.io/address/0xA6D1A0b97eC9BDdBB08Cb0824ea342AB78712Fc2 ), if you click that link to the etherscan address, you will see what I mean. You can click "internal transactions" tab right next to "transactions."

I can only find a "technical sounding" description of the difference between a regular transaction and an "internal transaction" : an internal transaction is the consequence of smart contract logic that is triggered by an external transaction

But then I'm left with the question, "Well, what is an EXTERNAL transaction then?"

Hope this clarifies.

[krakxn]

A simplified explanation to distinguish both would be:

External txns: Transactions involving two addresses which do not involve any smart contract. Hence, no SC-logic (which could supposedly lead to further automated txns)

Internal txns: Transactions involving a smart contract, or b/w smart contracts (can further branch out to smart contract logic which leads to even more txns—hence the suitable name, internal txns)

[alymurtazamemon]

@krakxn 👍