Replace viper with standard JSON decoding

Fixes #817

Author: glyn

Gopkg.lock

@@ -2,10 +2,6 @@
   name = "github.com/spf13/cobra"
   version = "0.0.3"
 
-[[constraint]]
-  name = "github.com/spf13/viper"
-  version = "v1.2"
-
 [[constraint]]
   name = "github.com/Masterminds/semver"
   version = "1.4.2"

Gopkg.toml

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -16,7 +17,6 @@ import (
 	"github.com/deislabs/cnab-go/bundle/definition"
 	"github.com/deislabs/cnab-go/claim"
 	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
 )
 
 const installUsage = `Installs a Cloud Native Application Bundle (CNAB)
@@ -218,13 +218,15 @@ func overrides(overrides []string, paramDefs definition.Definitions) (map[string
 }
 
 func parseValues(file string) (map[string]interface{}, error) {
-	v := viper.New()
-	v.SetConfigFile(file)
-	err := v.ReadInConfig()
+	vals := map[string]interface{}{}
+	f, err := ioutil.ReadFile(file)
 	if err != nil {
 		return nil, err
 	}
-	return v.AllSettings(), nil
+	if err := json.Unmarshal(f, &vals); err != nil {
+		return nil, err
+	}
+	return vals, nil
 }
 
 func calculateParamValues(bun *bundle.Bundle, valuesFile string, setParams, setFilePaths []string, prevVals map[string]interface{}) (map[string]interface{}, error) {

cmd/duffle/install.go

@@ -1,32 +1,27 @@
 package manifest
 
 import (
-	"fmt"
+	"encoding/json"
+	"os"
 	"path/filepath"
 
-	"github.com/spf13/viper"
-
 	"github.com/deislabs/duffle/pkg/duffle"
 )
 
-// Load opens the named file for reading. If successful, the manifest is returned.
+// Load parses the named file into a manifest.
 func Load(name, dir string) (*Manifest, error) {
-	v := viper.New()
 	if name == "" {
-		v.SetConfigName(duffle.DuffleFilename)
-	} else {
-		v.SetConfigFile(filepath.Join(dir, name))
+		name = duffle.DuffleFilename + ".json"
 	}
-	v.AddConfigPath(dir)
-	err := v.ReadInConfig()
+	f, err := os.Open(filepath.Join(dir, name))
 	if err != nil {
-		return nil, fmt.Errorf("Error finding duffle config file: %s", err)
+		return nil, err
 	}
 
-	m := New()
-	err = v.Unmarshal(m)
-	if err != nil {
+	manifest := New()
+	if err := json.NewDecoder(f).Decode(&manifest); err != nil {
 		return nil, err
 	}
-	return m, nil
+
+	return manifest, nil
 }

pkg/duffle/manifest/load.go

@@ -12,27 +12,27 @@ import (
 
 // Manifest represents a duffle manifest.
 type Manifest struct {
-	Name             string                       `json:"name" mapstructure:"name"`
-	Version          string                       `json:"version" mapstructure:"version"`
-	SchemaVersion    string                       `json:"schemaVersion" mapstructure:"schemaVersion"`
-	Description      string                       `json:"description,omitempty" mapstructure:"description"`
-	Keywords         []string                     `json:"keywords,omitempty" mapstructure:"keywords"`
-	Maintainers      []bundle.Maintainer          `json:"maintainers,omitempty" mapstructure:"maintainers"`
-	InvocationImages map[string]*InvocationImage  `json:"invocationImages,omitempty" mapstructure:"invocationImages"`
-	Images           map[string]bundle.Image      `json:"images,omitempty" mapstructure:"images"`
-	Actions          map[string]bundle.Action     `json:"actions,omitempty" mapstructure:"actions"`
-	Parameters       *bundle.ParametersDefinition `json:"parameters,omitempty" mapstructure:"parameters"`
-	Credentials      map[string]bundle.Credential `json:"credentials,omitempty" mapstructure:"credentials"`
-	Definitions      definition.Definitions       `json:"definitions,omitempty" mapstructure:"definitions"`
-	Outputs          *bundle.OutputsDefinition    `json:"outputs,omitempty" mapstructure:"outputs"`
-	Custom           map[string]interface{}       `json:"custom,omitempty" mapstructure:"custom"`
+	Name             string                       `json:"name"`
+	Version          string                       `json:"version"`
+	SchemaVersion    string                       `json:"schemaVersion"`
+	Description      string                       `json:"description,omitempty"`
+	Keywords         []string                     `json:"keywords,omitempty"`
+	Maintainers      []bundle.Maintainer          `json:"maintainers,omitempty"`
+	InvocationImages map[string]*InvocationImage  `json:"invocationImages,omitempty"`
+	Images           map[string]bundle.Image      `json:"images,omitempty"`
+	Actions          map[string]bundle.Action     `json:"actions,omitempty"`
+	Parameters       *bundle.ParametersDefinition `json:"parameters,omitempty"`
+	Credentials      map[string]bundle.Credential `json:"credentials,omitempty"`
+	Definitions      definition.Definitions       `json:"definitions,omitempty"`
+	Outputs          *bundle.OutputsDefinition    `json:"outputs,omitempty"`
+	Custom           map[string]interface{}       `json:"custom,omitempty"`
 }
 
 // InvocationImage represents an invocation image component of a CNAB bundle
 type InvocationImage struct {
-	Name          string            `json:"name" mapstructure:"name"`
-	Builder       string            `json:"builder" mapstructure:"builder"`
-	Configuration map[string]string `json:"configuration" mapstructure:"configuration"`
+	Name          string            `json:"name"`
+	Builder       string            `json:"builder"`
+	Configuration map[string]string `json:"configuration"`
 }
 
 // New creates a new manifest with the Environments intialized.

pkg/duffle/manifest/manifest.go

@@ -110,8 +110,8 @@ func TestInvalidLoad(t *testing.T) {
 			if err == nil {
 				t.Errorf("expected an error to be thrown")
 			}
-			if !strings.Contains(err.Error(), "error(s) decoding") {
-				t.Errorf("expected err to contain %s but was %s", "error(s) decoding", err.Error())
+			if !strings.Contains(err.Error(), "json: cannot unmarshal array into Go struct field") {
+				t.Errorf("expected err to contain %s but was %s", "json: cannot unmarshal array into Go struct field", err.Error())
 			}
 		})
 	}