It does not work for me when using "v4"

[InFog]

This is the reason why I removed it from the guide.

This is the message I was getting:

package github.com/labstack/echo/v4: cannot find package "github.com/labstack/echo/v4" in any of:
    /usr/lib/go-1.13/src/github.com/labstack/echo/v4 (from $GOROOT)
    /home/junior/go/src/github.com/labstack/echo/v4 (from $GOPATH)

[InFog]

Update: I also tried it using Go 1.14. Still not working using the v4 example.

[lammel]

Using the outdated v3 version of echo is not an option anymore ;-)

Could you please open an issue instead and describe the steps you took there. This might have been caused by a recent merge to update the docs to v4.

[InFog]

Hi, @lammel.

I checked the README and it says only a couple specific versions of Go will understand using /vN suffix. When I opened the PR I was using Go 1.13 and maybe that was the cause of the issue, but now I'm on 1.14.7 and it is still not working. I ran go get github.com/labstack/echo and it properly installed Echo v4 (Commit 429a8db01d8ef92a568a98ab2a0c4275c3dfbe7e), but for some reason using /v4 does not work.

The steps:

$ mkdir myproject
$ cd myproject
$ go get github.com/labstack/echo/v4
package github.com/labstack/echo/v4: cannot find package "github.com/labstack/echo/v4" in any of:
    /usr/lib/go-1.14/src/github.com/labstack/echo/v4 (from $GOROOT)
    /home/junior/go/src/github.com/labstack/echo/v4 (from $GOPATH)
$ go get github.com/labstack/echo
$ echo $?
0

Just to be clear, if I install if with no /v4 prefix this is what I get when running the server:

   ____    __
  / __/___/ /  ___
 / _// __/ _ \/ _ \
/___/\__/_//_/\___/ v4.1.17
High performance, minimalist Go web framework

So, v4 is used anyway.

[lammel]

There must be something wrong with your GOPATH or lokal go.mod file. It just works as expected for me (removed pkgs from $GOPATH first)

rl@slimboy# go get -v github.com/labstack/echo/v4                                                                                                                      go: downloading github.com/labstack/echo/v4 v4.1.17
go: downloading golang.org/x/net v0.0.0-20201202161906-c7110b5ffcbb
go: downloading golang.org/x/crypto v0.0.0-20201203163018-be400aefbc4c
go: downloading github.com/labstack/gommon v0.3.0
go: downloading github.com/valyala/fasttemplate v1.2.1
go: downloading github.com/mattn/go-colorable v0.1.8
go: downloading github.com/mattn/go-isatty v0.0.12
go: downloading golang.org/x/sys v0.0.0-20201204225414-ed752295db88
go: downloading github.com/valyala/bytebufferpool v1.0.0
go: downloading golang.org/x/text v0.3.4

This is rather strange. Please cleanup all github.com/labstack packages from your GOPATH oder vendor dir and retry with go get -v github.com/labstack/echo/v4.

To be sure what is currently installed use find $GOPATH/pkg/mod/github.com/labstack and check for local go.mod file.

[InFog]

Thank you for the help, @lammel, I really appreciate it.

So, still no success here.

$ go get -v github.com/labstack/echo/v4       
github.com/labstack/echo (download)
package github.com/labstack/echo/v4: cannot find package "github.com/labstack/echo/v4" in any of:
    /usr/lib/go-1.14/src/github.com/labstack/echo/v4 (from $GOROOT)
    /home/junior/go/src/github.com/labstack/echo/v4 (from $GOPATH)

$ go version                                  
go version go1.14.7 linux/amd64

The go.mod installed file reads:

module github.com/labstack/echo/v4

go 1.15

require (
    github.com/dgrijalva/jwt-go v3.2.0+incompatible
    github.com/labstack/gommon v0.3.0
    github.com/mattn/go-colorable v0.1.7 // indirect
    github.com/stretchr/testify v1.4.0
    github.com/valyala/fasttemplate v1.2.1
    golang.org/x/crypto v0.0.0-20200820211705-5c72a883971a
    golang.org/x/net v0.0.0-20200822124328-c89045814202
    golang.org/x/sys v0.0.0-20200826173525-f9321e4c35a6 // indirect
    golang.org/x/text v0.3.3 // indirect
)

Strange... because the go version I have here is 1.14.

Somehow I have the correct version, but installing it with /v4 does not work.

[lammel]

I tried to reproduce the issue you are facing but it works out for me. echo v4 is only tagged for echo/v4 so I'm not sure, why it even works for you as your output states the version cannot be downloaded....

Which plattform are you using (Win/Linux/Mac)?

I even retested with an empty GOPATH:

rl@slimboy# export GOPATH=/tmp/go
rl@slimboy# go get -v github.com/labstack/echo
go: downloading github.com/labstack/echo v3.3.10+incompatible
go: downloading github.com/labstack/gommon v0.3.0
go: downloading golang.org/x/crypto v0.0.0-20200820211705-5c72a883971a
go: downloading github.com/mattn/go-isatty v0.0.12
go: downloading github.com/mattn/go-colorable v0.1.7
go: downloading github.com/valyala/fasttemplate v1.2.1
go: downloading golang.org/x/sys v0.0.0-20200826173525-f9321e4c35a6
go: downloading github.com/valyala/bytebufferpool v1.0.0
go: downloading golang.org/x/net v0.0.0-20200822124328-c89045814202
go: downloading golang.org/x/text v0.3.3
golang.org/x/sys/internal/unsafeheader
github.com/valyala/bytebufferpool
golang.org/x/text/transform
golang.org/x/sys/unix
golang.org/x/text/unicode/bidi
golang.org/x/crypto/acme
github.com/valyala/fasttemplate
golang.org/x/text/unicode/norm
golang.org/x/text/secure/bidirule
golang.org/x/net/idna
github.com/mattn/go-isatty
golang.org/x/crypto/acme/autocert
github.com/mattn/go-colorable
github.com/labstack/gommon/color
github.com/labstack/gommon/log
github.com/labstack/echo

After installation only the expected latest echo v3 version is installed to the Go path:

rl@slimboy# find /tmp/go -name '*echo*' -type d
/tmp/go/pkg/mod/github.com/labstack/echo@v3.3.10+incompatible
/tmp/go/pkg/mod/cache/download/github.com/labstack/echo

[InFog]

Which go version are you using, @lammel ?

[lammel]

Good catch. It is indeed not working with go v1.14.

rl@einstein# go1.14.1 get github.com/labstack/echo/v4                                                                                                                      package github.com/labstack/echo/v4: cannot find package "github.com/labstack/echo/v4" in any of:
    /home/rl/sdk/go1.14.1/src/github.com/labstack/echo/v4 (from $GOROOT)
    /tmp/go/src/github.com/labstack/echo/v4 (from $GOPATH)

For v1.13 and v1.14 the GO111MODULE=on is needed:

rl@einstein /t  GO111MODULE=on go1.14.1 get github.com/labstack/echo/v4                                                                                                     go: downloading github.com/labstack/echo v1.4.4
go: downloading github.com/labstack/echo/v4 v4.1.17
go: downloading github.com/labstack/echo v3.3.10+incompatible
go: github.com/labstack/echo/v4 upgrade => v4.1.17
...

I've pushed a fix (on master accidently) now, so I think we can close this PR. Let me know if it works for you too with GO111MODULE=on. A nice article with an explaination is here

[InFog]

Yep, with GO111MODULE=on it works.

Also, thanks for the link, it helped me understanding the issue with Go dependencies.

[lammel]

Me too ;-)