undefined: libp2p.NoEncryption error prevents application to compile and run

[grempe]

From blog post:

https://medium.com/coinmonks/code-a-simple-p2p-blockchain-in-go-46662601f417

If not commented out, this line breaks compilation of the sample program:

https://github.com/mycoralhealth/blockchain-tutorial/blob/master/p2p/main.go#L74

linter declares undefined libp2p.NoEncryption

Trying to run it results in:

$ go run main.go -l 10000 -secio
# command-line-arguments
./main.go:75:23: undefined: libp2p.NoEncryption

Commenting it out allows the program to run as expected.

[nosequeldeebee]

It looks like go-libp2p did indeed remove that method: https://godoc.org/github.com/libp2p/go-libp2p

Do you want to submit a pull request with that !secio section removed from the code?

[jorge-abarca]

While go-libp2p removed the NoEncryption method, the contributors added a variable that seems to be its replacement: NoSecurity.

You can see in their next commit that their echo example for a basic host changed NoEncryption() for NoSecurity.

I see the whole check was removed in #14 from the blockchain-tutorial repository, since the secio parameter and flag are still a part of the example, perhaps it would make sense to add the following lines of code on line 73:

if !secio {
	opts = append(opts, libp2p.NoSecurity)
}

These would be the replacement lines of go-libp2p's example. They seem to still be used at this moment.

I will submit a pull request with this change if that is more convenient for you.

[jorge-abarca]

I submitted PR #39, if you are interested to bring back the secio check functionality.