website: go tour should give better error for missing package

[gopherbot]

by simonedichiara@maior.biz:

OS: Windows Seven Ultimate
Go: go version go1.0.1
GOROOT: C:\Go\
Path: C:\Go\bin
Install Package: go1.0.1.windows-amd64.msi
Browser: Firefox, IE, Chrome

The problem is the go tour won't compile. I hit run, "Waiting for remote
server" appears, then disappers and nothing happens.
I saw that http://127.0.0.1:3999/compile returns an empty json, like the following:
{"output":"","compile_errors":""}
Post data, instead, seems correct: 

body    
  package main 

  import "fmt" 

  func main() { 
    fmt.Println("Hello, 世界") 
  }

Attachments:

1. firefox_compile.JPG (160892 bytes)
2. Chrome_compile.JPG (158351 bytes)
3. firefox_post_data.JPG (40650 bytes)

[alexbrainman]

Comment 1:

I have no problem with Go Tour on windows:
C:\a\code\src>go get -v -d code.google.com/p/go-tour/
code.google.com/p/go-tour (download)
package code.google.com/p/go-tour
        imports code.google.com/p/go-tour
        imports code.google.com/p/go-tour: no Go source files in C:\a\code\src\code.google.com\p\go
tour
C:\a\code\src>cd code.google.com\p\go-tour\gotour
C:\a\code\src\code.google.com\p\go-tour\gotour>go build -v
code.google.com/p/go-tour/pic
code.google.com/p/go-tour/tree
code.google.com/p/go-tour/wc
code.google.com/p/go-tour/gotour
C:\a\code\src\code.google.com\p\go-tour\gotour>dir
 Volume in drive C has no label.
 Volume Serial Number is AAAA-BBBB
 Directory of C:\a\code\src\code.google.com\p\go-tour\gotour
02/05/2012  10:13 AM    <DIR>          .
02/05/2012  10:13 AM    <DIR>          ..
02/05/2012  10:11 AM               710 goplay.go
02/05/2012  10:13 AM         4,990,464 gotour.exe
02/05/2012  10:11 AM             4,169 local.go
               3 File(s)      4,995,343 bytes
               2 Dir(s)  132,038,553,600 bytes free
C:\a\code\src\code.google.com\p\go-tour\gotour>gotour.exe -help
Usage of gotour.exe:
  -html=false: render program output as HTML
  -http="127.0.0.1:3999": host:port to listen on
C:\a\code\src\code.google.com\p\go-tour\gotour>gotour.exe
2012/05/02 10:13:42 Serving content from C:\a\code\src\code.google.com\p\go-tour
2012/05/02 10:13:42 Open your web browser and visit http://127.0.0.1:3999/
C:\a\code\src\code.google.com\p\go-tour\gotour>set | find "GO"
GOPATH=C:\a\code
GOROOT=C:\a\go
LOGONSERVER=\\AURDC002
C:\a\code\src\code.google.com\p\go-tour\gotour>
I can open web browser on http://127.0.0.1:3999/ once gotour.exe is running. I can see
first page with "Hello ..." example. I can press "Run" button. I can see "Hello ..."
output printed in my browser.
Can you, please, tell us what steps you did, and which of the steps you got something
you didn't expect to get.
Thank you.
Alex

Status changed to WaitingForReply.

[gopherbot]

Comment 2 by simonedichiara@maior.biz:

Since the instructions only say: 
  You can also run it locally. First install Go and then use go to install gotour:
  go get code.google.com/p/go-tour/gotour
  and run the gotour executable. 
I didn't have done this: C:\a\code\src\code.google.com\p\go-tour\gotour>go build -v. And
that way it didn't work for me. 
As you described, it works. Thank you.
I think this http://code.google.com/p/go-tour/issues/detail?id=33 is a similar problem.

[alexbrainman]

Comment 3:

It says "use go to install gotour". I think gotour authors assume that you know how to
use "go tool", if you are installing gotour locally.
Perhaps some doco clarification required somewhere. Leaving it for adg.
Alex

Owner changed to @adg.

Status changed to WorkingAsIntended.

[gopherbot]

Comment 4 by simonedichiara@maior.biz:

I was using this C:\Go\bin\gotour.exe and it didn't work. 
I assumed that "use go to install gotour" simply meant to run this: "go get
code.google.com/p/go-tour/gotour". It actually generated the executable that I was using
(C:\Go\bin\gotour.exe) and so I thought that that was the way it was meant to be.
Anyway, thank you very much. :)

[alexbrainman]

Comment 5:

Using C:\Go\bin\gotour.exe should work too. If you build and install it with
C:\a\code\src\code.google.com\p\go-tour\gotour>go install
command. Please note, my GOPATH=C:\a\code, so my gotour.exe will end up in
C:\a\code\bin\gotour.exe. Is it similar with you? Maybe you are running wrong
gotour.exe, and it is out of date.
Alex

Status changed to WaitingForReply.

[gopherbot]

Comment 6 by simonedichiara@maior.biz:

I installed go. 
Then in the cmd shell I wrote "go get code.google.com/p/go-tour/gotour" and hit Enter.
No message displayed since I didn't use any parameter.
Then I executed the file C:\Go\bin\gotour.exe and it didn't work, as I described in my
first post.
Then I wrote here and, after your answer, I tried this:
"C:\Go\src\pkg\code.google.com\p\go-tour\gotour go build -v"
It compiled a gotour.exe in the same folder
(C:\Go\src\pkg\code.google.com\p\go-tour\gotour in my case). This new executable worked
fine for me.
I don't know if the other one, placed in C:\Go\bin\gotour.exe after "go get
code.google.com/p/go-tour/gotour", is and older version. But it's existence in that
folder confounded me, as it didn't work.
I know my english is not so good, so if you need any clarification, I can try to write
it out. xD

[alexbrainman]

Comment 7:

>
> Comment #6 on issue #3583 by simonedichiara@maior.biz: Local Go Tour doesn't
> compile
> https://golang.org/issue/3583
>
> I installed go.
> Then in the cmd shell I wrote "go get code.google.com/p/go-tour/gotour" and
> hit Enter.
> No message displayed since I didn't use any parameter.
That means that "go get" command worked successfully. Otherwise, it would complain. If
you want to see what "go get" command is doing in details, use "-x" flag.
> Then I executed the file C:\Go\bin\gotour.exe and it didn't work, as I
> described in my first post.
If you delete C:\Go\bin\gotour.exe file and try to build and install it again:
go install -x code.google.com/p/go-tour/gotour
you will see (because of -x) what "go install" command is doing and where it is
installing resulting executable. Perhaps it is doing something you do not expect.
Please, also run these commands
C:\a\code\src>go env
set GOROOT=C:\a\go
set GOBIN=
set GOARCH=386
set GOCHAR=8
set GOOS=windows
set GOEXE=.exe
set GOHOSTARCH=386
set GOHOSTOS=windows
set GOTOOLDIR=C:\a\go\pkg\tool\windows_386
set GOGCCFLAGS=-g -O2 -m32 -mthreads
set CGO_ENABLED=1
C:\a\code\src>set | find "GO"
GOPATH=C:\a\code
GOROOT=C:\a\go
and show results, to help us understand your environment.
> Then I wrote here and, after your answer, I tried this:
> "C:\Go\src\pkg\code.google.com\p\go-tour\gotour go build -v"
> It compiled a gotour.exe in the same folder
> (C:\Go\src\pkg\code.google.com\p\go-tour\gotour in my case). This new
> executable worked fine for me.
If you run "go build" command in C:\Go\src\pkg\code.google.com\p\go-tour\gotour, it will
just build gotour program and save it in the same folder where source files are. Unlike
"go install", it does not install its results into %GOPATH%\bin or %GOPATH%\pkg
directories.
If you want to use "go" command, you should, probably, read some manuals about it. For
example:
http://golang.org/doc/code.html
http://golang.org/cmd/go/
Alex

[gopherbot]

Comment 8 by simonedichiara@maior.biz:

Ok, I think we reproduced the problem.
Here my environment:
C:\Users\WIT>go env
set GOROOT=C:\Go
set GOBIN=
set GOARCH=amd64
set GOCHAR=6
set GOOS=windows
set GOEXE=.exe
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOTOOLDIR=C:\Go\pkg\
set GOGCCFLAGS=-g -O2 -m
set CGO_ENABLED=1
Then I deleted the following file: C:\Go\bin\gotour.exe
Then I used the "go install": 
C:\Users\WIT>go install -x code.google.com/p/go-tour/gotour
WORK=C:\Users\WIT\AppData\Local\Temp\go-build796384398
mkdir -p $WORK\code.google.com\p\go-tour\gotour\_obj\
cd C:\Go\src\pkg\code.google.com\p\go-tour\gotour
C:\Go\pkg\tool\windows_amd64\6g.exe -o
$WORK\code.google.com\p\go-tour\gotour\_obj\_go_.6 -p code.google.com/p/go-tour/gotour
-D _/C_/Go/src/pkg/code.google.com/p/go-tour/gotour -I $WORK .\goplay.go .\local.go
C:\Go\pkg\tool\windows_amd64\pack.exe grc $WORK\code.google.com\p\go-tour\gotour.a
$WORK\code.google.com\p\go-tour\gotour\_obj\_go_.6
cd .
C:\Go\pkg\tool\windows_amd64\6l.exe -o
$WORK\code.google.com\p\go-tour\gotour\_obj\a.out.exe -L $WORK
$WORK\code.google.com\p\go-tour\gotour.a
mkdir -p C:\Go\bin\
cp $WORK\code.google.com\p\go-tour\gotour\_obj\a.out.exe C:\Go\bin\gotour.exe
It, as expected, recreated the file C:\Go\bin\gotour.exe. But this file doesn't work for
me. It gives me the problem I described in my first post here. I compile e nothing
happens.
So:
- C:\a\code\src\code.google.com\p\go-tour\gotour>go build -v <-- THIS WORKS FOR ME
- go install -x code.google.com/p/go-tour/gotour <-- THIS DOESN'T WORK

[alexbrainman]

Comment 9:

I can't reproduce your problem. And I have no good ideas where to look. The only thing
that looks suspicious in your setup is your GOTOOLDIR value - mine is
GOTOOLDIR=c:\go\pkg\tool\windows_386.
The only good suggestion I have is for you to look at gotour program itself, to see
where and why it breaks. You should be able to put print statements to make sure all
code is executed as expected.
Leaving it for others.
Alex

Status changed to Accepted.

[gopherbot]

Comment 10 by simonedichiara@maior.biz:

I don't know if this could help, but:
I changed this: 
    if err != nil {
        if out != nil {
            resp.Errors = string(out)
        } else {
            resp.Errors = err.Error()
        }
    } else {
        resp.Output = string(out)
    }
To this:
    if err != nil {
        if out != nil {
            log.Println("out != nil")
            log.Println(string(out))
            resp.Errors = string(out)
        } else {
            log.Println("out == nil")
            log.Println(err.Error())
            resp.Errors = err.Error()
        }
    } else {
        log.Println("err == nil")
        log.Println(string(out))
        resp.Output = string(out)
    }
The output is in the attached file.

Attachments:

1. compile_test_go_tour.JPG (31151 bytes)

[gopherbot]

Comment 11 by simonedichiara@maior.biz:

The file I modified is this: code.google.com/p/go-tour/gotour/goplay.go

[gopherbot]

Comment 12 by simonedichiara@maior.biz:

I printed err.Error()
        if out != nil {
            log.Println("out != nil")
            log.Println(string(out))
            log.Println(err.Error())
            resp.Errors = string(out)
        } 
The output is in the attached file.

Attachments:

1. compile_test_go_tour_error_print.JPG (35991 bytes)

[gopherbot]

Comment 13 by simonedichiara@maior.biz:

The error in the preceding posts happens only when I use "go install -x
code.google.com/p/go-tour/gotour".
It doesn't happen if I use "C:\Go\src\pkg\code.google.com\p\go-tour\gotour>go build -v".

Attachments:

1. compile_test_go_tour_good_print.JPG (32074 bytes)

[gopherbot]

Comment 14 by simonedichiara@maior.biz:

Ok, the error happens only when the file gotour.exe is in the following directory:
"C:\Go\bin". If I run it from that path, it doesn't work. If I run it from somewhere
else, there are no problems.

[gopherbot]

Comment 15 by simonedichiara@maior.biz:

I think that goplay.go should at least be changed like this, to ensure it always return
an error when there is one, and doesn't return the empty output:
        if out != nil && string(out) != "" {
            resp.Errors = string(out)
        } else {
            resp.Errors = err.Error()
        }
I don't know if this is the correct way to do it, but that's the idea.

Attachments:

1. compile_after_change.JPG (45338 bytes)

[alexbrainman]

Comment 16:

Your last findings do help. But I need more information. Please show us output of all
these commands:
dir C:\Go\src\pkg\code.google.com\p\go-tour\gotour
dir C:\Go\bin\gotour.exe
echo %PATH%
Thank you.
There are many problems you are seeing. It seems, gotour sometimes can't find go.exe to
be able to compile code samples from web browser. We do not know why yet, but if you
answer my request, I might make some suggestions.
You do not see error message, because gotour.exe does not show it to you (as you have
discovered). It is not correct behavior, so I have asked to change gotour
(http://golang.org/cl/6201066/). Hopefully, if my change is accepted, you will
be able to see your error message properly.
Next problem is the error message: ".\go.exe: error 2 (Format Message failed with
err=15100)". My message now says "exec: "go": executable file not found in %PATH%". So,
I wonder, why yours is different. Also, it seems syscall.FormatMessage winapi function
failed to fetch English error message for your error #2 (ERROR_FILE_NOT_FOUND). That is
another mystery to investigate. But one thing at a time. :-)
Alex

[gopherbot]

Comment 17 by simonedichiara@maior.biz:

Output of the commands, as you requested:
Microsoft Windows [Versione 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. Tutti i diritti riservati.
C:\Users\WIT>dir C:\Go\src\pkg\code.google.com\p\go-tour\gotour
 Il volume nell'unità C non ha etichetta.
 Numero di serie del volume: D6B2-D948
 Directory di C:\Go\src\pkg\code.google.com\p\go-tour\gotour
08/05/2012  23:21    <DIR>          .
08/05/2012  23:21    <DIR>          ..
09/05/2012  08:45               792 goplay.go
08/05/2012  21:05             4.169 local.go
               2 File          4.961 byte
               2 Directory  61.870.792.704 byte disponibili
C:\Users\WIT>dir C:\Go\bin\gotour.exe
 Il volume nell'unità C non ha etichetta.
 Numero di serie del volume: D6B2-D948
 Directory di C:\Go\bin
09/05/2012  08:24         5.435.392 gotour.exe
               1 File      5.435.392 byte
               0 Directory  61.870.559.232 byte disponibili
C:\Users\WIT>echo %PATH%
C:\Program Files (x86)\AMD APP\bin\x86_64;C:\Program Files (x86)\AMD APP\bin\x86
;C:\Program Files (x86)\PC Connectivity Solution\;C:\Program Files (x86)\MiKTeX
2.9\miktex\bin;C:\Program Files\Common Files\Microsoft Shared\Windows Live;C:\Pr
ogram Files (x86)\Common Files\Microsoft Shared\Windows Live;C:\Windows\system32
;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\
;C:\Program Files (x86)\ATI Technologies\ATI.ACE\Core-Static;C:\Program Files (x
86)\Windows Live\Shared;C:\Program Files (x86)\Common Files\Acronis\SnapAPI\;C:\
Program Files\Mercurial;C:\Program Files\TortoiseHg\;C:\Program Files (x86)\Micr
osoft SQL Server\100\Tools\Binn\;C:\Program Files\Microsoft SQL Server\100\Tools
\Binn\;C:\Program Files\Microsoft SQL Server\100\DTS\Binn\;C:\Program Files (x86
)\Microsoft ASP.NET\ASP.NET Web Pages\v1.0\;C:\Program Files (x86)\Calibre2\;C:\
Go\bin

[gopherbot]

Comment 18 by simonedichiara@maior.biz:

This resolved my problem about the path of gotour, but doesn't make it more
understandable. I modified code.google.com/p/go-tour/gotour/local.go
From this: out, err = run(dir, "go", "build", "-o", bin, file)
To this: var goroot = runtime.GOROOT()
         var gobin = goroot + "bin\\go"
     out, err = run(dir, gobin, "build", "-o", bin, file)

[gopherbot]

Comment 19 by simonedichiara@maior.biz:

For linux:
    var goroot = runtime.GOROOT()
    var gobin = ""
    if runtime.GOOS == "windows" {
        gobin = goroot + "bin\\go"
    } else {
        gobin = goroot + "/bin/go"
    }
As before, I know this maybe not right, but it's just a suggestion.
I hope this will help. :)

[gopherbot]

Comment 20 by simonedichiara@maior.biz:

I tried, as far as I can, to track down the problem.
I modified os/exec/exec.go like this: log.Println("START FILE: " + c.Path), so that I
could look at the file it was trying to execute.
So, when gotour.exe is in the following dir "C:\Go\bin" the executed file is this:
".\go.exe". This doesn't work.
When gotour.exe is, for example, on the desktop, the executed file is this:
"C:\Go\bin\go.exe". And this works. The same is when I put gotour.exe on C: and so on.

[gopherbot]

Comment 21 by simonedichiara@maior.biz:

Could the problem be that os.Stat() succeeds at looking for info about the file, even if
the path is something like this ".\go.exe", but os.StartProcess cannot execute it that
way?

[alexbrainman]

Comment 22:

Your problem is you can't run go.exe. But sometimes you can.
Perhaps, your go.exe is not in your PATH. But sometimes it happens to be in your
"current" directory. The way Windows finds executables to run, it looks in the current
directory first, then it searches every directory listed in PATH environment variable in
turn. Your PATH is quite long, but the only one that looks like Go related is C:\Go\bin
in the very end. Please, run
dir C:\Go\bin\
to see if go.exe is in there. Also, if you run this:
package main
import (
    "fmt"
    "log"
    "os/exec"
)
func main() {
    exe, err := exec.LookPath("go")
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("go program lives in %s\n", exe)
}
it should tell you where your go.exe lives.
If you have go.exe in C:\Go\bin\, then you should be able to run it from there, like this
cd c:\go\bin
.\go.exe
Try it from command line see if that works.
Perhaps, your c:\go\bin\go.exe is corrupted or something, and you are actually running
go.exe from some other directory. But when you are in c:\go\bin then go.exe there has to
be tried first, and it fails. Try my little program above and run it from different
places and see what it does.
Thank you.
Alex

[gopherbot]

Comment 23 by simonedichiara@maior.biz:

I tested with your app from various paths (desktop, c:, c:\go\bin). Output is in the
attached files. All the log print is from my other tests. I hope it doesn't bother you.
I tried this: 
  cd c:\go\bin
  .\go.exe
and it works without problems.
> Perhaps, your c:\go\bin\go.exe is corrupted or something, and you are actually running
go.exe from some other directory.
From my previous tests I think it runs the right go.exe: when I put "gotour.exe" in a
directory that is not "c:\go\bin", it tries to run "C:\Go\bin\go.exe" and this works.
When "gotour.exe" is in "c:\go\bin", it tries to run ".\go.exe" and this doesn't work.

Attachments:

1. go_app_test_c_root.JPG (148103 bytes)
2. go_app_test_desktop.JPG (156972 bytes)
3. go_app_test_go_bin.JPG (154557 bytes)

[gopherbot]

Comment 24 by simonedichiara@maior.biz:

One screenshot for all the tests. The previous were done wrong. I'm sorry. :)

Attachments:

1. go_app_test_all.JPG (314493 bytes)

[alexbrainman]

Comment 25:

I think I can recreate your problem now. I started new
https://golang.org/issue/3622, because, I think, it is Go related
(not go-tour).
I also do not like the error message you are getting, so I started
https://golang.org/issue/3623 to track it separately too. Please run
program listed there and post your results in
https://golang.org/issue/3623.
Thank you.
Alex

[rsc]

Comment 26:

I changed the tour web site to say 'go get code.google.com/p/go-tour/...' which should
install both the binary and the packages. However, we should still make the error
reporting better.

[rsc]

Comment 27:

Labels changed: added priority-later, removed priority-triage.

[rsc]

Comment 28:

Labels changed: added go1.2maybe.

[rsc]

Comment 29:

Labels changed: added documentation.

[robpike]

Comment 30:

Labels changed: removed go1.2maybe.

[rsc]

Comment 31:

Labels changed: added go1.3maybe.

[rsc]

Comment 32:

Labels changed: added release-none, removed go1.3maybe.

[adg]

Comment 33:

Labels changed: added repo-tour.

[adg]

Comment 34:

I doubt this is still a real issue.

Status changed to TimedOut.