Setting up a logger 

  log.Printf("message %s", "Hello World")

Network requests

Set Headers

  req.Header = http.Header{
    "Host": {"www.host.com"},
    "Content-Type": {"application/json"},
    "Authorization": {"Bearer Token"},
}

Can also do this, but note that Host header cannot be set this way

  req.Header.Set("Key", "Value")

Network Request

Flags

Check to see if a flag was changed or not

  modelFlagModified := flag.Lookup("model").Changed

Build Args

Go build Link

  main.go:
var inputVariable = "defaultValue"

bash:
go build -ldflags "-X main.inputValue=setValue" -o myapp
  
  -X importpath.name=value
	Set the value of the string variable in importpath named name to value.
	This is only effective if the variable is declared in the source code either uninitialized
	or initialized to a constant string expression. -X will not work if the initializer makes
	a function call or refers to other variables.
	Note that before Go 1.5 this option took two separate arguments.

Also note, to add to another package, you have to specify it by full path. So if the package “cmd” is located at app/cmd, you would set the build args like this:

  module_name="demo-cli"

BUILD_ARGS+=("-X" "'$module_name/app/cmd.binaryName=$app_name'")
BUILD_ARGS+=("-X" "'$module_name/app/cmd.gitVersion=$git_version'")
BUILD_ARGS+=("-X" "'$module_name/app/cmd.buildTime=$build_time'")