kjk / go-cookbook Goto Github PK

Hi.
on https://blog.kowalczyk.info/article/Jl3G/https-for-free-in-go-with-little-help-of-lets-encrypt.html
this link to code is broken- https://github.com/kjk/the-code/tree/master/free-ssl-certificates

Missing "/go" in path and should be https://github.com/kjk/the-code/tree/master/go/free-ssl-certificates

hey, I stumbled upon your article https://blog.kowalczyk.info/article/Jl3G/https-for-free-in-go-with-little-help-of-lets-encrypt.html

Is there any way to get publickey from cache? is it covered on your book?
and is publickey change when renewed after 3 month?

Line 48 of the code prints the output and the error(if any) from the external command's result.

go-cookbook/advanced-exec/03-live-progress-and-capture-v3.go

But I see that the output is printed first.
Then again under "out:"

I couldn't understand which part of the code is printing the first output.
Using: go version go1.11.2 windows/amd64

I'm following the free-ssl-certificates example, changed allowedHost to mine and httpPort to :80, and it is working, at least for the http part. However, the https part is not working.

When the program starts, it prints on the console:
Starting HTTP server on :80
Starting HTTPS server on :443

When using the https connection,

I'm getting

This site can’t be reached
site took too long to respond.

Checking back to the console, I see:

2019/05/07 11:11:11 http: TLS handshake error from 99.xx.xx.221:40820: context deadline exceeded
2019/05/07 11:11:11 http: TLS handshake error from 99.xx.xx.221:40826: acme/autocert: missing certificate
2019/05/07 11:11:11 http: TLS handshake error from 99.xx.xx.221:40828: acme/autocert: missing certificate
2019/05/07 11:11:11 http: TLS handshake error from 99.xx.xx.221:40822: acme/autocert: missing certificate
2019/05/07 11:11:11 http: TLS handshake error from 99.xx.xx.221:40830: acme/autocert: missing certificate
2019/05/07 11:11:11 http: TLS handshake error from 99.xx.xx.221:40832: acme/autocert: missing certificate
2019/05/07 11:11:11 http: TLS handshake error from 99.xx.xx.221:40860: acme/autocert: missing certificate
2019/05/07 11:11:11 http: TLS handshake error from 99.xx.xx.221:40824: acme/autocert: missing certificate

How to make it works? thx

Once again, I have a real site whose DNS name matches allowedHost. I've changed allowedHost to match, and it is working (by visiting my true DNS name) -- no complaining from the log, even with https.

New to golang, so bare with me if I don't understand some parts correctly :)
03-live-progress-and-capture-v1.go looks wrong with regards to parallelism:
in line 47 the cmd is actually started, while only later two goroutines try to capture stdOut and stdErr.
Hence if your computer is slow or loaded, the cmd is already finished and copyAndCapture will fail to get a hold on anything.
If I add a simple time.Sleep(100 * time.Millisecond) after the cmd.Start() to simulate slowness, I get two error behaviours from time to time:

1. rarely, but still sometimes copyAndCapture will fail to read (in line 19) but get an error read |0: file already closed
2. most of the times copyAndCapture will miss the output (I didn't understand how that happens): the output is visible in my shell, but outStr will be empty, hence no output from the captured string

Now this can be fixed in practice by shifting cmd.Start() e.g. to line 56, after the goroutines were started. While that works in practice, I still think it's not absolutely correct as go probably doesn't guarantees when the actual code of a goroutine is executed, so while cmd.Start() would appear later in the code, still copyAndCapture might be executed "too late".

Hi,

I'm following the free-ssl-certificates example, changed allowedHost to mine, and it is working, at least for the http part. However, the https part is not working.

When the program starts, it prints on the console:

Starting HTTP server on 127.0.0.1:8080
Starting HTTPS server on :443

• Is that normal? Shouldn't HTTPS server has an IP address as well?

• Visiting http://127.0.0.1:8080 works fine, but when trying to visit https://127.0.0.1:443/, I'll get

    This site can’t provide a secure connection
  

So,

• Am I suppose to visit https://127.0.0.1:443/?
• Shall I change more than the allowedHost, e.g., the httpPort as well? If so, what to change to?

thx