libcni: Improved error messages.

Improved the error reporting to be more descriptive when configuration
files are not filed while using the cni-tool.

diff --git a/libcni/conf.go b/libcni/conf.go
index 4fa2bfe..c7738c6 100644 (file)
--- a/libcni/conf.go
+++ b/libcni/conf.go
@@ -16,7 +16,6 @@ package libcni
 
 import (
        "encoding/json"
-       "errors"
        "fmt"
        "io/ioutil"
        "os"
@@ -33,7 +32,13 @@ func (e NotFoundError) Error() string {
        return fmt.Sprintf(`no net configuration with name "%s" in %s`, e.Name, e.Dir)
 }
 
-var NoConfigsFoundError = errors.New("no net configurations found")
+type NoConfigsFoundError struct {
+       Dir string
+}
+
+func (e NoConfigsFoundError) Error() string {
+       return fmt.Sprintf(`no net configurations found in %s`, e.Dir)
+}
 
 func ConfFromBytes(bytes []byte) (*NetworkConfig, error) {
        conf := &NetworkConfig{Bytes: bytes}
@@ -149,7 +154,7 @@ func LoadConf(dir, name string) (*NetworkConfig, error) {
        case err != nil:
                return nil, err
        case len(files) == 0:
-               return nil, NoConfigsFoundError
+               return nil, NoConfigsFoundError{Dir: dir}
        }
        sort.Strings(files)
 
@@ -187,16 +192,12 @@ func LoadConfList(dir, name string) (*NetworkConfigList, error) {
        singleConf, err := LoadConf(dir, name)
        if err != nil {
                // A little extra logic so the error makes sense
-               switch {
-               // neither configlists nor config files found
-               case len(files) == 0 && err == NoConfigsFoundError:
-                       return nil, err
-               // config lists found but no config files found
-               case len(files) != 0 && err == NoConfigsFoundError:
+               if _, ok := err.(NoConfigsFoundError); len(files) != 0 && ok {
+                       // Config lists found but no config files found
                        return nil, NotFoundError{dir, name}
-               default: // either not found or parse error
-                       return nil, err
                }
+
+               return nil, err
        }
        return ConfListFromConf(singleConf)
 }