I thought that after getting the bytes, chunk the data, I need to have the
io.writer back before send the chunked data
So far I came up with this:
...
cmd.Stdin = conn
buf := new(bytes.Buffer)
cmd.Stdout = buf
bizz := buf.Bytes()
var i int
for {
n := int(math.Min(float64(rand.Intn(len(bizz))), float64(len(bizz))))
d := bizz[i : i+n]
i += n
z := bytes.NewBuffer(d)
kk := io.Writer(z)
//this line creates the error
time.Sleep(400 * time.Millisecond)
kk = conn
if i >= len(bizz) {
break
}
}
cmd.Stderr = conn
cmd.Run()
.....
But know I get this error:
conn.go:95:21: kk declared but not used
Il giorno mercoledì 7 luglio 2021 alle 15:49:56 UTC+2 mlevi...@gmail.com ha
scritto:
> You cannot *per se* convert an interface or a struct to a builtin like
> []byte
> You might wanna have a look at the Bytes method
> <https://golang.org/pkg/bytes/#Buffer.Bytes> of *bytes.Buffer, which
> returns the internal buffer of the type as a slice of bytes. Normally that
> would have been a good exercise to let you find it yourself, and I don't
> know if it is really "help" to give it to you directly, but as I said, once
> you are done with your small tool, the next step for you will be to go back
> from the basic Go constructs :)
>
> Glad I could help, and don't bother with the comments, the best "thank
> you" I can wish for is that we continue learning together ;)
> Hope the following adventures of your Go journey are as interesting as
> they are for me!
>
> Cheers
>
> Le mer. 7 juil. 2021 à 15:08, LetGo <non3...@gmail.com> a écrit :
>
>> Thanks for your answer!(:
>> You are right, but I just wanted to have this one little tool in Go and
>> I have never thought that could be that hard... ahahah
>>
>> By the way, it works as you said, it fixed the error! ( obviously.. )
>> the only thing left is to convert type *bytes.Buffer to []byte * I think*
>> and then I will be almost done.
>> Im already searching how to do that.
>>
>> Once it will work as I wish, I will add your names to my comments ( I
>> think this is better than any "thank you" ) in the code, to remind me of
>> your kind help(:
>>
>>
>>
>> Il giorno mercoledì 7 luglio 2021 alle 14:01:33 UTC+2 mlevi...@gmail.com
>> ha scritto:
>>
>>> [Sorry forgot to hit "Reply all"]
>>>
>>> Are you trying to cast cmd.Stdout here?
>>> What you can do is:
>>> buf := new(bytes.Buffer)
>>> cmd.Stdout = buf // buf is an io.Writer so this is fine
>>>
>>> but I don't get the point of the data := foo?
>>>
>>> Maybe, before trying to convert a whole complex program in Python to a
>>> whole working program in Go, you should take time to familiarize yourself
>>> with the language.
>>> Go through the Go tour <https://tour.golang.org/welcome/1>, read a
>>> little of the specs, have yourself code some small, simple programs that
>>> don't require using lots of std packages at once...
>>>
>>> Once you are familiar with the language constructs, which I have to say
>>> are pretty different from Python's, you will have a better understanding of
>>> where to start and how to implement your program. Otherwise I think this
>>> will all only get you confused.
>>> And understanding at least the important basics of Go will help you
>>> explain your pain points here, if any remains :)
>>>
>>> Hope this helps,
>>>
>>> Le mer. 7 juil. 2021 à 12:41, LetGo <non3...@gmail.com> a écrit :
>>>
>>>> One of these is this:
>>>> ...
>>>> buf := new(bytes.Buffer)
>>>> foo := buf(cmd.Stdout) // this line is 87
>>>> data := foo
>>>> var i int
>>>> ...
>>>>
>>>> pkg/conn.go:87:20: cannot call non-function buf (type *bytes.Buffer)
>>>> Il giorno mercoledì 7 luglio 2021 alle 12:10:03 UTC+2 LetGo ha scritto:
>>>>
>>>>> I tried also both of them, but I got stuck into a loop of errors
>>>>> again.. probably I coded in the wrong way
>>>>>
>>>>> Il giorno mercoledì 7 luglio 2021 alle 11:50:51 UTC+2 Brian Candler ha
>>>>> scritto:
>>>>>
>>>>>> It makes no sense to convert an io.Writer to a string.
>>>>>>
>>>>>> io.Writer is an interface: any type which has a Write() method. So
>>>>>> you can pass a string *to* a writer, to get it written somewhere, by
>>>>>> calling the Write() method. In general, you can't get a string *from* a
>>>>>> writer. If you google "go io.Writer" you'll get lots of tutorials and
>>>>>> examples.
>>>>>>
>>>>>> Depending on your application though, you might want to create a
>>>>>> bytes.Buffer <https://golang.org/pkg/bytes/#Buffer> or
>>>>>> strings.Builder <https://golang.org/pkg/strings/#Builder> object,
>>>>>> both of which are an io.Writer. The written data gets appended to a
>>>>>> buffer
>>>>>> that you can read later.
>>>>>>
>>>>>> On Wednesday, 7 July 2021 at 10:07:19 UTC+1 LetGo wrote:
>>>>>>
>>>>>>> Thanks for your answer!(:
>>>>>>> You are right, sorry!
>>>>>>> This is the code: https://play.golang.org/p/zEZ2HIUNffs
>>>>>>>
>>>>>>> About the lines, wow! Yes, you got them! ahah
>>>>>>> About the errors, I tried to convert ( cmd.Stdout ) io.Write to
>>>>>>> bytes/ strings, but.. I have then entered into a loop of errors...
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Il giorno martedì 6 luglio 2021 alle 21:32:10 UTC+2 Brian Candler ha
>>>>>>> scritto:
>>>>>>>
>>>>>>>> You haven't shown which lines 75, 76 and 83 correspond to. It's
>>>>>>>> easier if you put the whole code on play.golang.org, and we'll be
>>>>>>>> able to point to the error.
>>>>>>>>
>>>>>>>> But I'm guessing it's this:
>>>>>>>> data := cmd.Stdout
>>>>>>>> ...
>>>>>>>> n := int(math.Min(float64(rand.Intn(len(data))),
>>>>>>>> float64(len(data)))) << line 75?
>>>>>>>> d := data[i : i+n] << line 76?
>>>>>>>> ...
>>>>>>>> if i >= len(data) { << line 83?
>>>>>>>>
>>>>>>>> If I'm right, the compiler is saying: cmd.Stdout (which you
>>>>>>>> assigned to 'data') is of type io.Writer. It's not a string; you
>>>>>>>> can't
>>>>>>>> take len(...) of an io.Writer, nor can you slice it.
>>>>>>>>
>>>>>>>> On Tuesday, 6 July 2021 at 16:03:26 UTC+1 LetGo wrote:
>>>>>>>>
>>>>>>>>> I think I made some progress.... I think. Is it right what I'm
>>>>>>>>> doing ?
>>>>>>>>>
>>>>>>>>> ................
>>>>>>>>> cmd.Stdin = conn
>>>>>>>>> // cmd.Stdout = conn
>>>>>>>>> // data := []byte(cmd.Stdout)
>>>>>>>>> data := cmd.Stdout
>>>>>>>>> var i int
>>>>>>>>> for {
>>>>>>>>> n := int(math.Min(float64(rand.Intn(len(data))),
>>>>>>>>> float64(len(data))))
>>>>>>>>> d := data[i : i+n]
>>>>>>>>> i += n
>>>>>>>>> time.Sleep(400 * time.Millisecond)
>>>>>>>>> d = conn
>>>>>>>>>
>>>>>>>>> if i >= len(data) {
>>>>>>>>> break
>>>>>>>>> }
>>>>>>>>> }
>>>>>>>>> cmd.Stderr = conn
>>>>>>>>> cmd.Run()
>>>>>>>>> ............................
>>>>>>>>>
>>>>>>>>> But when I try to build I get these errors:
>>>>>>>>>
>>>>>>>>> conn.go:75:46: invalid argument data (type io.Writer) for len
>>>>>>>>> conn.go:76:16: cannot slice data (type io.Writer)
>>>>>>>>> conn.go:83:22: invalid argument data (type io.Writer) for len
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Il giorno martedì 29 giugno 2021 alle 19:37:04 UTC+2 LetGo ha
>>>>>>>>> scritto:
>>>>>>>>>
>>>>>>>>>> Thank you guys for all your answers and suggestions!
>>>>>>>>>> I really appreciate!
>>>>>>>>>> Sorry about the screenshots, it was the only way to make the
>>>>>>>>>> packets "human readable"
>>>>>>>>>> How could you code that kind of implementation based on your
>>>>>>>>>> knowledge and skill?
>>>>>>>>>> I have noone of these in golang ahah as I said, im too newbie to
>>>>>>>>>> do all this alone!
>>>>>>>>>> Also not working examples ( if they throw an error I don't care,
>>>>>>>>>> based on my code are fine!
>>>>>>>>>> These examples could rapresent a great start from me!(:
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Il giorno martedì 29 giugno 2021 alle 19:00:06 UTC+2
>>>>>>>>>> jesper.lou...@gmail.com ha scritto:
>>>>>>>>>>
>>>>>>>>>>> On Tue, Jun 29, 2021 at 5:24 PM LetGo <non3...@gmail.com> wrote:
>>>>>>>>>>>
>>>>>>>>>>>> Thanks for the answer! (:
>>>>>>>>>>>> In python it was straightforward to implement and it works like
>>>>>>>>>>>> a charm. It sends small packets with delay between each other
>>>>>>>>>>>> without even
>>>>>>>>>>>> care if it is UDP or TCP:
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>> Beware! This is an assumption that will break at some point in
>>>>>>>>>>> time. Currently the delay and the OS makes things straightforward
>>>>>>>>>>> for you.
>>>>>>>>>>> But TCP doesn't behave like you expect, and you are very likely to
>>>>>>>>>>> run into
>>>>>>>>>>> trouble if the machine, the network, or the system starts taking
>>>>>>>>>>> additional
>>>>>>>>>>> load.
>>>>>>>>>>>
>>>>>>>>>>> You need to frame the data. A good way is to use 4 bytes as a
>>>>>>>>>>> size (unsigned 32 bit integer), followed by a payload of that size.
>>>>>>>>>>> You can
>>>>>>>>>>> then avoid this becoming an uncontrolled explosion in your software
>>>>>>>>>>> at a
>>>>>>>>>>> later date. You can also close connections early if too large
>>>>>>>>>>> messages get
>>>>>>>>>>> sent, etc.
>>>>>>>>>>>
>>>>>>>>>>> --
>>>> You received this message because you are subscribed to the Google
>>>> Groups "golang-nuts" group.
>>>> To unsubscribe from this group and stop receiving emails from it, send
>>>> an email to golang-nuts...@googlegroups.com.
>>>>
>>> To view this discussion on the web visit
>>>> https://groups.google.com/d/msgid/golang-nuts/466d016b-b90b-4505-b4a8-7e5fc62679b4n%40googlegroups.com
>>>>
>>>> <https://groups.google.com/d/msgid/golang-nuts/466d016b-b90b-4505-b4a8-7e5fc62679b4n%40googlegroups.com?utm_medium=email&utm_source=footer>
>>>> .
>>>>
>>> --
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>>
>> <https://groups.google.com/d/msgid/golang-nuts/0f12076e-f325-4583-ba85-857084aec83dn%40googlegroups.com?utm_medium=email&utm_source=footer>
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>>
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