Merge pull request #94 from ricardoseriani/avoid-ssh-file-not-found-e…

…rror

Avoid ssh config file not found error

README.md

@@ -10,7 +10,7 @@ For more information about installation, usage, examples and specific use cases,
 
 ### Build and Install from Source
 
-* [Go 1.12.5+](https://golang.org/dl/) is required
+* [Go 1.13+](https://golang.org/dl/) is required
 * Mole uses [Go Modules](https://blog.golang.org/using-go-modules) to manage its dependencies, so remember to clone the project outside `GOPATH` and unset it.
 
 ```sh

tunnel/config.go

@@ -41,6 +41,11 @@ func NewSSHConfigFile() (*SSHConfigFile, error) {
 	return &SSHConfigFile{sshConfig: cfg}, nil
 }
 
+func NewEmptySSHConfigStruct() *SSHConfigFile {
+	log.Debugf("generating an empty config struct")
+	return &SSHConfigFile{sshConfig: &ssh_config.Config{}}
+}
+
 // Get consults a ssh config file to extract some ssh server attributes
 // from it, returning a SSHHost. Any attribute which its value is an empty
 // string is an attribute that could not be found in the ssh config file.

tunnel/tunnel.go

@@ -1,6 +1,7 @@
 package tunnel
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"net"
@@ -49,7 +50,15 @@ func NewServer(user, address, key string) (*Server, error) {
 
 	c, err := NewSSHConfigFile()
 	if err != nil {
-		return nil, fmt.Errorf("error accessing %s: %v", host, err)
+		// Ignore file doesnt exists
+		if !errors.Is(err, os.ErrNotExist) {
+			return nil, fmt.Errorf("error accessing %s: %v", host, err)
+		}
+	}
+
+	// // If ssh config file doesnt exists, create an empty ssh config struct to avoid nil pointer deference
+	if errors.Is(err, os.ErrNotExist) {
+		c = NewEmptySSHConfigStruct()
 	}
 
 	h := c.Get(host)