I have a go project whose structure is:
- internal
- client.go
main.go
go.mod
go.mod:
module github.com/zhaoyi0113/eml-transaction
go 1.17
require github.com/go-resty/resty/v2 v2.7.0
require golang.org/x/net v0.0.0-20211029224645-99673261e6eb // indirect
client.go:
func SendTransaction() {
}
main.go
package main
import (
"bufio"
"fmt"
"os"
"strconv"
"strings"
)
import "github.com/zhaoyi0113/eml-transaction/internal"
func main() {
SendTransaction()
}
The problem is that SendTransaction is invisible in main.go. When I run go build, I got below error:
./main.go:11:8: imported and not used: "github.com/zhaoyi0113/eml-transaction/internal"
./main.go:36:2: undefined: SendTransaction
./main.go:36:18: undefined: TransactionRequest
I don't understand why the import is not used. What is the right way to import it?
Just figured out how it works. I have to use internal as the prefix to call this method.
internal.SendTransaction(internal.TransactionRequest{})
``
Related
I am trying to run a simple hello world style program that imports a print function from a separate custom package but Go is unable to find it despite teh correct $GOPATH etc being set.
What is missing that will make teh file be picked up?
etherk1ll#ubuntu:~/Development/GoWorkSpace/src/sonarparser$ echo $GOPATH
/home/etherk1ll/Development/GoWorkSpace/
etherk1ll#ubuntu:~/Development/GoWorkSpace/src/sonarparser$ pwd
/home/etherk1ll/Development/GoWorkSpace/src/sonarparser
etherk1ll#ubuntu:~/Development/GoWorkSpace/src/sonarparser$ ls
jsonparser.go main.go
etherk1ll#ubuntu:~/Development/GoWorkSpace/src/sonarparser$ go run main.go
main.go:5:2: cannot find package "sonarparser/jsonparser" in any of:
/usr/local/go/src/sonarparser/jsonparser (from $GOROOT)
/home/etherk1ll/Development/GoWorkSpace/src/sonarparser/jsonparser (from $GOPATH)
main.go
package main
import (
"fmt"
"jsonparser"
)
func main() {
fmt.Println("Hello world 1")
fmt.Println(jsonparser.HelloTwo)
}
jsonparser.go
package jsonparser
import "fmt"
func HelloTwo() {
fmt.Println("Hello world 2")
}
Because jsonparser.go and main.go are in the same package, Go requires those files to have the same package name. And because you defined the main function for the execution, the package must be "main".
Step 1: So you should rename jsonparser.go's package to main.
// jsonparser.go
package main
import "fmt"
func HelloTwo() {
fmt.Println("Hello world 2")
}
Step 2: You need to update main.go file to correct the import path:
// main.go
package main
import (
"fmt"
)
func main() {
fmt.Println("Hello world 1")
HelloTwo()
}
Step 3: Then you run the following command (you must include all necessary files in the command)
go run main.go jsonparser.go
I can't understand why this :/
I tried go get -u ** with every url that I found.
Thanks
Golang:
$ go version
go version go1.13.3 windows/amd64
Source test:
package main
import (
"fmt"
"cloud.google.com/go/datastore"
)
var client *datastore.Client
func main() {
fmt.Println("Work")
}
Error:
$ go run main.go
# google.golang.org/grpc/internal/transport
..\..\..\..\google.golang.org\grpc\internal\transport\http_util.go:270:23: cannot use hf (type "vendor/golang.org/x/net/http2/hpack".HeaderField) as type
"golang.org/x/net/http2/hpack".HeaderField in argument to d.processHeaderField
..\..\..\..\google.golang.org\grpc\internal\transport\http_util.go:675:23: cannot use "golang.org/x/net/http2/hpack".NewDecoder(http2InitHeaderTableSize,
nil) (type *"golang.org/x/net/http2/hpack".Decoder) as type *"vendor/golang.org/x/net/http2/hpack".Decoder in assignment
Go requires you make use of any package that you import. In this case you are importing "cloud.google.com/go/datastore" but not doing anything with it. The global variable that you declared is also not being used. Since it seems you are just trying to test, so I would recommend you do something with it (atleast print it). Like-
package main
import (
"fmt"
"cloud.google.com/go/datastore"
)
var client *datastore.Client
func main() {
fmt.Println(client)
}
It appears that I cannot import this package: github.com/golang/protobuf/proto
When I try to build or use go get I get:cannot load github.com/golang/protobuf/proto: module github.com/golang/protobuf#latest (v1.3.2) found, but does not contain package github.com/golang/protobuf/proto
It is a popular package, I am surprised it does not seem to be working.
https://godoc.org/github.com/golang/protobuf/proto#Marshal
Has anybody encountered this?
Update:
I am simply trying to import this:
import (
"bytes"
"context"
"encoding/json"
"errors"
"fmt"
"github.com/golang/protobuf/proto"
)
GoLang does not resolve proto in the above path...
I try to install like this:
$ go get github.com/golang/protobuf/proto
go: finding github.com/golang/protobuf/proto latest
go get github.com/golang/protobuf/proto: module github.com/golang/protobuf#upgrade (v1.3.2) found, but does not contain package github.com/golang/protobuf/proto
Update2, not sure how the file helps but here it is:
package main
import (
"bytes"
"context"
"encoding/json"
"errors"
"fmt"
"github.com/golang/protobuf/proto"
"go_poc/plugins/com_styx_proto"
"io/ioutil"
"net/http"
"time"
)
func init() {
fmt.Println("styxBotDetect plugin is loaded!")
}
func (r registrable) RegisterHandlers(f func(
name string,
handler func(
context.Context,
map[string]interface{},
http.Handler) (http.Handler, error),
)) {
f(pluginName, r.registerHandlers)
}
func (r registrable) registerHandlers(ctx context.Context, extra map[string]interface{}, handler http.Handler) (http.Handler, error) {
// skipping some lines here
styxRqBytes, err := proto.Marshal(styxRq)
if err != nil {
http.Error(w, err.Error(), http.StatusNotAcceptable)
return
}
// more code
It turns out there was something wrong with the module cache, that's why the go tool was not able to fetch / update dependencies.
In such cases, clearing the module cache (might) help:
go clean -modcache
On the Terminal window, please run the following commands,
go clean -modcache
go get -u github.com/golang/protobuf/proto
Then run the following commands to get the packages downloaded and update in the .mod file
go mod init Version1
go mod tidy
I am attempting to do a local import but it fails.
My environment is:
echo $GOPATH
/home/peter/go
echo $GOROOT
/usr/local/go
The entry point is:
/home/peter/go/src/projects/pkgs1/main.go
The imported file is:
/home/peter/go/src/projects/pkgs2/stuff.go
main.go
package main
import (
"fmt"
"projects/pkgs2" // <- this does not resolve
)
func main(){
fmt.Println("123")
pkgs2.X()
}
stuff.go
package pkgs2
import "fmt"
func X(){
fmt.Println("X")
}
Any pointers on what I do wrong?
Your import path is correct and should resolve successfully, but as written, your program won't compile because the import isn't being used and there is no local function named x.
As mentioned by mkopriva your x function in pkgs2 isn't exported and you have not qualified it when trying to use it in your main package.
To export a function, it needs to start with a capital letter.
To use the function in another package, you need to prefix the package name to the function name.
main.go
package main
import (
"fmt"
"projects/pkgs2"
)
func main(){
fmt.Println("123")
pkgs2.X()
}
stuff.go
package pkgs2
import "fmt"
func X(){
fmt.Println("X")
}
Why the following works
package main
import (
"os"
cli "github.com/urfave/cli"
)
func main() {
cli.NewApp().Run(os.Args)
}
but when I change the cli import to following as suggested in https://github.com/urfave/cli
import (
"os"
cli "gopkg.in/urfave/cli.v2"
)
It gives this error undefined: cli.NewApp
v2 of the package has no NewApp() method.
As it doesn't initialize with defaults the example below is not exactly the same as the NewApp() method, but you can try something like this, if you want to give v2 of the package a try.
package main
import (
"os"
cli "gopkg.in/urfave/cli.v2"
)
func main() {
(&cli.App{}).Run(os.Args)
}
Make sure to read the README.md file contained in the v2 package, as it also contains updated instructions and examples.