1. View the Go file: exercise-maps.go, the code is as follows
package main
import (
"code.google.com/p/go-tour/wc"
)
func WordCount(s string) map[string]int {
return map[string]int{"x": 1}
}
func main() {
wc.Test(WordCount)
}
2. Run the file, Go reports an error: exercise-maps.go:4:2: cannot find package “code.google.com/p/go-tour/wc” in any of:
c:\go\src\code.google.com\p\go-tour\wc (from $GOROOT)
C:\Users\Administrator\go\src\code.google.com\p\go-tour\wc (from $GOPATH), as shown in Figure 1
PS E:\wwwroot\go\moretypes> go run exercise-maps.go
exercise-maps.go:4:2: cannot find package "code.google.com/p/go-tour/wc" in any of:
c:\go\src\code.google.com\p\go-tour\wc (from $GOROOT)
C:\Users\Administrator\go\src\code.google.com\p\go-tour\wc (from $GOPATH)
3. Open the Go Tour GitHub URL: https://github.com/golang/tour . After enabling the Lantern connection, install Go Tour from source. It reports an error: unrecognized import path “golang.org/x/tour”. Pinging golang.org prompts request timed out, as shown in Figure 2
PS E:\wwwroot\go\moretypes> go get golang.org/x/tour
package golang.org/x/tour: unrecognized import path "golang.org/x/tour" (https fetch: Get https://golang.org/x/tour?go-g
et=1: dial tcp 216.239.37.1:443: connectex: A connection attempt failed because the connected party did not properly res
pond after a period of time, or established connection failed because connected host has failed to respond.)
4. Open the URL https://golang.org/ in Chrome, and it loads normally, as shown in Figure 3
5. Use Lantern to configure an HTTP proxy for the command line. View Lantern’s advanced settings – HTTP(S) proxy server, as shown in Figure 4
6. Set the two environment variables HTTP_PROXY and HTTPS_PROXY in cmd. Execute the following two commands to set the environment variables and complete the configuration. Installing Go Tour from source no longer reports an error. Although Ping still fails, you can use Curl to open www.google.com, which indicates that the HTTP proxy has been set up successfully, as shown in Figure 5
C:\Users\Administrator>set HTTP_PROXY=http://127.0.0.1:50999
C:\Users\Administrator>set HTTPS_PROXY=http://127.0.0.1:50999
C:\Users\Administrator>go get golang.org/x/tour
C:\Users\Administrator>ping golang.org
Pinging golang.org [216.239.37.1] with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Ping statistics for 216.239.37.1:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),
C:\Users\Administrator>curl -vv http://www.google.com
* Rebuilt URL to: http://www.google.com/
* Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to 127.0.0.1 (127.0.0.1) port 50999 (#0)
> GET http://www.google.com/ HTTP/1.1
> Host: www.google.com
> User-Agent: curl/7.55.1
> Accept: */*
> Proxy-Connection: Keep-Alive
>
< HTTP/1.1 301 Moved Permanently
< Connection: close
< Cache-Control: max-age:86400
< Date: Friday, 27-Dec-19 16:57:05 CST
< Expires: Sat, 28 Dec 2019 16:57:05 GMT
< Keep-Alive: timeout=58
< Location: https://www.google.com/
< Content-Length: 0
<
* Closing connection 0
7. View the directory: C:\Users\Administrator\go\src\golang.org\x, the directory: tour already exists, as shown in Figure 6
8. Edit the Go file: exercise-maps.go, replace code.google.com/p/go-tour with: golang.org/x/tour, the code is as follows
package main
import (
"golang.org/x/tour/wc"
)
func WordCount(s string) map[string]int {
return map[string]int{"x": 1}
}
func main() {
wc.Test(WordCount)
}
9. Run the file, it runs normally, as shown in Figure 7
PS E:\wwwroot\go\moretypes> go run exercise-maps.go
FAIL
f("I am learning Go!") =
map[string]int{"x":1}
want:
map[string]int{"Go!":1, "I":1, "am":1, "learning":1}