Merge pull request #65779 from cblecker/mergo-update

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>. update github.com/imdario/mergo to v0.3.5 **What this PR does / why we need it**: Updates github.com/imdario/mergo library to v0.3.5. We were pinned because of a functionality change in the dependency, however, a new function was introduced with similar functionality to the old. There is apparently some Debian packaging issues (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=878254) because of this. I'm still not clear what those are, unless they are forcing the library to update, as opposed to using our `vendor/`. That said, this will allow for some of those vendor conflicts to resolve for anyone else who is using client-go, so that's at least worthwhile. **Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*: fixes #27543, fixes https://github.com/kubernetes/client-go/issues/431 **Special notes for your reviewer**: **Release note**: ```release-note NONE ```
2018-08-17 14:43:48 -07:00 · 2018-08-17 14:43:48 -07:00 · 6b41352679
parent 008165027b e9cf2b0f79
commit 6b41352679
17 changed files with 619 additions and 99 deletions
--- a/Godeps/Godeps.json
+++ b/Godeps/Godeps.json
@ -2246,8 +2246,8 @@
 		},
 		{
 			"ImportPath": "github.com/imdario/mergo",
-			"Comment": "0.1.3-8-g6633656",
-			"Rev": "6633656539c1639d9d78127b7d47c622b5d7b6dc"
+			"Comment": "v0.3.5",
+			"Rev": "9316a62528ac99aaecb4e47eadd6dc8aa6533d58"
 		},
 		{
 			"ImportPath": "github.com/inconshreveable/mousetrap",
--- a/staging/src/k8s.io/apiextensions-apiserver/Godeps/Godeps.json
+++ b/staging/src/k8s.io/apiextensions-apiserver/Godeps/Godeps.json
@ -536,7 +536,7 @@
 		},
 		{
 			"ImportPath": "github.com/imdario/mergo",
-			"Rev": "6633656539c1639d9d78127b7d47c622b5d7b6dc"
+			"Rev": "9316a62528ac99aaecb4e47eadd6dc8aa6533d58"
 		},
 		{
 			"ImportPath": "github.com/inconshreveable/mousetrap",
--- a/staging/src/k8s.io/apiserver/Godeps/Godeps.json
+++ b/staging/src/k8s.io/apiserver/Godeps/Godeps.json
@ -512,7 +512,7 @@
 		},
 		{
 			"ImportPath": "github.com/imdario/mergo",
-			"Rev": "6633656539c1639d9d78127b7d47c622b5d7b6dc"
+			"Rev": "9316a62528ac99aaecb4e47eadd6dc8aa6533d58"
 		},
 		{
 			"ImportPath": "github.com/jonboulle/clockwork",
--- a/staging/src/k8s.io/client-go/Godeps/Godeps.json
+++ b/staging/src/k8s.io/client-go/Godeps/Godeps.json
@ -156,7 +156,7 @@
 		},
 		{
 			"ImportPath": "github.com/imdario/mergo",
-			"Rev": "6633656539c1639d9d78127b7d47c622b5d7b6dc"
+			"Rev": "9316a62528ac99aaecb4e47eadd6dc8aa6533d58"
 		},
 		{
 			"ImportPath": "github.com/json-iterator/go",
--- a/staging/src/k8s.io/client-go/tools/clientcmd/client_config.go
+++ b/staging/src/k8s.io/client-go/tools/clientcmd/client_config.go
@ -175,10 +175,6 @@ func (config *DirectClientConfig) ClientConfig() (*restclient.Config, error) {
 	// only try to read the auth information if we are secure
 	if restclient.IsConfigTransportTLS(*clientConfig) {
 		var err error
-
-		// mergo is a first write wins for map value and a last writing wins for interface values
-		// NOTE: This behavior changed with https://github.com/imdario/mergo/commit/d304790b2ed594794496464fadd89d2bb266600a.
-		//       Our mergo.Merge version is older than this change.
 		var persister restclient.AuthProviderConfigPersister
 		if config.configAccess != nil {
 			authInfoName, _ := config.getAuthInfoName()
@ -188,13 +184,13 @@ func (config *DirectClientConfig) ClientConfig() (*restclient.Config, error) {
 		if err != nil {
 			return nil, err
 		}
-		mergo.Merge(clientConfig, userAuthPartialConfig)
+		mergo.MergeWithOverwrite(clientConfig, userAuthPartialConfig)

 		serverAuthPartialConfig, err := getServerIdentificationPartialConfig(configAuthInfo, configClusterInfo)
 		if err != nil {
 			return nil, err
 		}
-		mergo.Merge(clientConfig, serverAuthPartialConfig)
+		mergo.MergeWithOverwrite(clientConfig, serverAuthPartialConfig)
 	}

 	return clientConfig, nil
@ -214,7 +210,7 @@ func getServerIdentificationPartialConfig(configAuthInfo clientcmdapi.AuthInfo,
 	configClientConfig.CAFile = configClusterInfo.CertificateAuthority
 	configClientConfig.CAData = configClusterInfo.CertificateAuthorityData
 	configClientConfig.Insecure = configClusterInfo.InsecureSkipTLSVerify
-	mergo.Merge(mergedConfig, configClientConfig)
+	mergo.MergeWithOverwrite(mergedConfig, configClientConfig)

 	return mergedConfig, nil
 }
@ -279,8 +275,8 @@ func (config *DirectClientConfig) getUserIdentificationPartialConfig(configAuthI
 		promptedConfig := makeUserIdentificationConfig(*promptedAuthInfo)
 		previouslyMergedConfig := mergedConfig
 		mergedConfig = &restclient.Config{}
-		mergo.Merge(mergedConfig, promptedConfig)
-		mergo.Merge(mergedConfig, previouslyMergedConfig)
+		mergo.MergeWithOverwrite(mergedConfig, promptedConfig)
+		mergo.MergeWithOverwrite(mergedConfig, previouslyMergedConfig)
 		config.promptedCredentials.username = mergedConfig.Username
 		config.promptedCredentials.password = mergedConfig.Password
 	}
@ -423,11 +419,11 @@ func (config *DirectClientConfig) getContext() (clientcmdapi.Context, error) {

 	mergedContext := clientcmdapi.NewContext()
 	if configContext, exists := contexts[contextName]; exists {
-		mergo.Merge(mergedContext, configContext)
+		mergo.MergeWithOverwrite(mergedContext, configContext)
 	} else if required {
 		return clientcmdapi.Context{}, fmt.Errorf("context %q does not exist", contextName)
 	}
-	mergo.Merge(mergedContext, config.overrides.Context)
+	mergo.MergeWithOverwrite(mergedContext, config.overrides.Context)

 	return *mergedContext, nil
 }
@ -439,11 +435,11 @@ func (config *DirectClientConfig) getAuthInfo() (clientcmdapi.AuthInfo, error) {

 	mergedAuthInfo := clientcmdapi.NewAuthInfo()
 	if configAuthInfo, exists := authInfos[authInfoName]; exists {
-		mergo.Merge(mergedAuthInfo, configAuthInfo)
+		mergo.MergeWithOverwrite(mergedAuthInfo, configAuthInfo)
 	} else if required {
 		return clientcmdapi.AuthInfo{}, fmt.Errorf("auth info %q does not exist", authInfoName)
 	}
-	mergo.Merge(mergedAuthInfo, config.overrides.AuthInfo)
+	mergo.MergeWithOverwrite(mergedAuthInfo, config.overrides.AuthInfo)

 	return *mergedAuthInfo, nil
 }
@ -454,13 +450,13 @@ func (config *DirectClientConfig) getCluster() (clientcmdapi.Cluster, error) {
 	clusterInfoName, required := config.getClusterName()

 	mergedClusterInfo := clientcmdapi.NewCluster()
-	mergo.Merge(mergedClusterInfo, config.overrides.ClusterDefaults)
+	mergo.MergeWithOverwrite(mergedClusterInfo, config.overrides.ClusterDefaults)
 	if configClusterInfo, exists := clusterInfos[clusterInfoName]; exists {
-		mergo.Merge(mergedClusterInfo, configClusterInfo)
+		mergo.MergeWithOverwrite(mergedClusterInfo, configClusterInfo)
 	} else if required {
 		return clientcmdapi.Cluster{}, fmt.Errorf("cluster %q does not exist", clusterInfoName)
 	}
-	mergo.Merge(mergedClusterInfo, config.overrides.ClusterInfo)
+	mergo.MergeWithOverwrite(mergedClusterInfo, config.overrides.ClusterInfo)
 	// An override of --insecure-skip-tls-verify=true and no accompanying CA/CA data should clear already-set CA/CA data
 	// otherwise, a kubeconfig containing a CA reference would return an error that "CA and insecure-skip-tls-verify couldn't both be set"
 	caLen := len(config.overrides.ClusterInfo.CertificateAuthority)
--- a/staging/src/k8s.io/client-go/tools/clientcmd/client_config_test.go
+++ b/staging/src/k8s.io/client-go/tools/clientcmd/client_config_test.go
@ -28,21 +28,83 @@ import (
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
 )

-func TestOldMergoLib(t *testing.T) {
-	type T struct {
-		X string
+func TestMergoSemantics(t *testing.T) {
+	type U struct {
+		A string
+		B int64
 	}
-	dst := T{X: "one"}
-	src := T{X: "two"}
-	mergo.Merge(&dst, &src)
-	if dst.X != "two" {
-		// mergo.Merge changed in an incompatible way with
-		//
-		//   https://github.com/imdario/mergo/commit/d304790b2ed594794496464fadd89d2bb266600a
-		//
-		// We have to stay with the old version which still does eager
-		// copying from src to dst in structs.
-		t.Errorf("mergo.Merge library found with incompatible, new behavior")
+	type T struct {
+		S []string
+		X string
+		Y int64
+		U U
+	}
+	var testDataStruct = []struct {
+		dst      T
+		src      T
+		expected T
+	}{
+		{
+			dst:      T{X: "one"},
+			src:      T{X: "two"},
+			expected: T{X: "two"},
+		},
+		{
+			dst:      T{X: "one", Y: 5, U: U{A: "four", B: 6}},
+			src:      T{X: "two", U: U{A: "three", B: 4}},
+			expected: T{X: "two", Y: 5, U: U{A: "three", B: 4}},
+		},
+		{
+			dst:      T{S: []string{"test3", "test4", "test5"}},
+			src:      T{S: []string{"test1", "test2", "test3"}},
+			expected: T{S: []string{"test1", "test2", "test3"}},
+		},
+	}
+	for _, data := range testDataStruct {
+		err := mergo.MergeWithOverwrite(&data.dst, &data.src)
+		if err != nil {
+			t.Errorf("error while merging: %s", err)
+		}
+		if !reflect.DeepEqual(data.dst, data.expected) {
+			// The mergo library has previously changed in a an incompatible way.
+			// example:
+			//
+			//   https://github.com/imdario/mergo/commit/d304790b2ed594794496464fadd89d2bb266600a
+			//
+			// This test verifies that the semantics of the merge are what we expect.
+			// If they are not, the mergo library may have been updated and broken
+			// unexpectedly.
+			t.Errorf("mergo.MergeWithOverwrite did not provide expected output: %+v doesn't match %+v", data.dst, data.expected)
+		}
+	}
+
+	var testDataMap = []struct {
+		dst      map[string]int
+		src      map[string]int
+		expected map[string]int
+	}{
+		{
+			dst:      map[string]int{"rsc": 6543, "r": 2138, "gri": 1908, "adg": 912, "prt": 22},
+			src:      map[string]int{"rsc": 3711, "r": 2138, "gri": 1908, "adg": 912},
+			expected: map[string]int{"rsc": 3711, "r": 2138, "gri": 1908, "adg": 912, "prt": 22},
+		},
+	}
+	for _, data := range testDataMap {
+		err := mergo.MergeWithOverwrite(&data.dst, &data.src)
+		if err != nil {
+			t.Errorf("error while merging: %s", err)
+		}
+		if !reflect.DeepEqual(data.dst, data.expected) {
+			// The mergo library has previously changed in a an incompatible way.
+			// example:
+			//
+			//   https://github.com/imdario/mergo/commit/d304790b2ed594794496464fadd89d2bb266600a
+			//
+			// This test verifies that the semantics of the merge are what we expect.
+			// If they are not, the mergo library may have been updated and broken
+			// unexpectedly.
+			t.Errorf("mergo.MergeWithOverwrite did not provide expected output: %+v doesn't match %+v", data.dst, data.expected)
+		}
 	}
 }

@ -574,3 +636,46 @@ func TestNamespaceOverride(t *testing.T) {

 	matchStringArg("foo", ns, t)
 }
+
+func TestAuthConfigMerge(t *testing.T) {
+	content := `
+apiVersion: v1
+clusters:
+- cluster:
+    server: https://localhost:8080
+  name: foo-cluster
+contexts:
+- context:
+    cluster: foo-cluster
+    user: foo-user
+    namespace: bar
+  name: foo-context
+current-context: foo-context
+kind: Config
+users:
+- name: foo-user
+  user:
+    exec:
+      apiVersion: client.authentication.k8s.io/v1alpha1
+      args:
+      - arg-1
+      - arg-2
+      command: foo-command
+`
+	tmpfile, err := ioutil.TempFile("", "kubeconfig")
+	if err != nil {
+		t.Error(err)
+	}
+	defer os.Remove(tmpfile.Name())
+	if err := ioutil.WriteFile(tmpfile.Name(), []byte(content), 0666); err != nil {
+		t.Error(err)
+	}
+	config, err := BuildConfigFromFlags("", tmpfile.Name())
+	if err != nil {
+		t.Error(err)
+	}
+	if !reflect.DeepEqual(config.ExecProvider.Args, []string{"arg-1", "arg-2"}) {
+		t.Errorf("Got args %v when they should be %v\n", config.ExecProvider.Args, []string{"arg-1", "arg-2"})
+	}
+
+}
--- a/staging/src/k8s.io/client-go/tools/clientcmd/loader.go
+++ b/staging/src/k8s.io/client-go/tools/clientcmd/loader.go
@ -211,7 +211,7 @@ func (rules *ClientConfigLoadingRules) Load() (*clientcmdapi.Config, error) {
 	mapConfig := clientcmdapi.NewConfig()

 	for _, kubeconfig := range kubeconfigs {
-		mergo.Merge(mapConfig, kubeconfig)
+		mergo.MergeWithOverwrite(mapConfig, kubeconfig)
 	}

 	// merge all of the struct values in the reverse order so that priority is given correctly
@ -219,14 +219,14 @@ func (rules *ClientConfigLoadingRules) Load() (*clientcmdapi.Config, error) {
 	nonMapConfig := clientcmdapi.NewConfig()
 	for i := len(kubeconfigs) - 1; i >= 0; i-- {
 		kubeconfig := kubeconfigs[i]
-		mergo.Merge(nonMapConfig, kubeconfig)
+		mergo.MergeWithOverwrite(nonMapConfig, kubeconfig)
 	}

 	// since values are overwritten, but maps values are not, we can merge the non-map config on top of the map config and
 	// get the values we expect.
 	config := clientcmdapi.NewConfig()
-	mergo.Merge(config, mapConfig)
-	mergo.Merge(config, nonMapConfig)
+	mergo.MergeWithOverwrite(config, mapConfig)
+	mergo.MergeWithOverwrite(config, nonMapConfig)

 	if rules.ResolvePaths() {
 		if err := ResolveLocalPaths(config); err != nil {
--- a/staging/src/k8s.io/kube-aggregator/Godeps/Godeps.json
+++ b/staging/src/k8s.io/kube-aggregator/Godeps/Godeps.json
@ -228,7 +228,7 @@
 		},
 		{
 			"ImportPath": "github.com/imdario/mergo",
-			"Rev": "6633656539c1639d9d78127b7d47c622b5d7b6dc"
+			"Rev": "9316a62528ac99aaecb4e47eadd6dc8aa6533d58"
 		},
 		{
 			"ImportPath": "github.com/inconshreveable/mousetrap",
--- a/staging/src/k8s.io/sample-apiserver/Godeps/Godeps.json
+++ b/staging/src/k8s.io/sample-apiserver/Godeps/Godeps.json
@ -220,7 +220,7 @@
 		},
 		{
 			"ImportPath": "github.com/imdario/mergo",
-			"Rev": "6633656539c1639d9d78127b7d47c622b5d7b6dc"
+			"Rev": "9316a62528ac99aaecb4e47eadd6dc8aa6533d58"
 		},
 		{
 			"ImportPath": "github.com/inconshreveable/mousetrap",
--- a/staging/src/k8s.io/sample-controller/Godeps/Godeps.json
+++ b/staging/src/k8s.io/sample-controller/Godeps/Godeps.json
@ -88,7 +88,7 @@
 		},
 		{
 			"ImportPath": "github.com/imdario/mergo",
-			"Rev": "6633656539c1639d9d78127b7d47c622b5d7b6dc"
+			"Rev": "9316a62528ac99aaecb4e47eadd6dc8aa6533d58"
 		},
 		{
 			"ImportPath": "github.com/json-iterator/go",
--- a/vendor/github.com/imdario/mergo/.gitignore
+++ b/vendor/github.com/imdario/mergo/.gitignore
@ -0,0 +1,33 @@
+#### joe made this: http://goel.io/joe
+
+#### go ####
+# Binaries for programs and plugins
+*.exe
+*.dll
+*.so
+*.dylib
+
+# Test binary, build with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Project-local glide cache, RE: https://github.com/Masterminds/glide/issues/736
+.glide/
+
+#### vim ####
+# Swap
+[._]*.s[a-v][a-z]
+[._]*.sw[a-p]
+[._]s[a-v][a-z]
+[._]sw[a-p]
+
+# Session
+Session.vim
+
+# Temporary
+.netrwhist
+*~
+# Auto-generated tag files
+tags
--- a/vendor/github.com/imdario/mergo/.travis.yml
+++ b/vendor/github.com/imdario/mergo/.travis.yml
@ -1,2 +1,7 @@
 language: go
-install: go get -t
+install:
+  - go get -t
+  - go get golang.org/x/tools/cmd/cover
+  - go get github.com/mattn/goveralls
+script:
+  - $HOME/gopath/bin/goveralls -service=travis-ci -repotoken $COVERALLS_TOKEN
--- a/vendor/github.com/imdario/mergo/CODE_OF_CONDUCT.md
+++ b/vendor/github.com/imdario/mergo/CODE_OF_CONDUCT.md
@ -0,0 +1,46 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as contributors and maintainers pledge to making participation in our project and our community a harassment-free experience for everyone, regardless of age, body size, disability, ethnicity, gender identity and expression, level of experience, nationality, personal appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable behavior and are expected to take appropriate and fair corrective action in response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct, or to ban temporarily or permanently any contributor for other behaviors that they deem inappropriate, threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces when an individual is representing the project or its community. Examples of representing a project or community include using an official project e-mail address, posting via an official social media account, or acting as an appointed representative at an online or offline event. Representation of a project may be further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by contacting the project team at i@dario.im. The project team will review and investigate all complaints, and will respond in a way that it deems appropriate to the circumstances. The project team is obligated to maintain confidentiality with regard to the reporter of an incident. Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good faith may face temporary or permanent repercussions as determined by other members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4, available at [http://contributor-covenant.org/version/1/4][version]
+
+[homepage]: http://contributor-covenant.org
+[version]: http://contributor-covenant.org/version/1/4/
--- a/vendor/github.com/imdario/mergo/README.md
+++ b/vendor/github.com/imdario/mergo/README.md
@ -2,14 +2,72 @@

 A helper to merge structs and maps in Golang. Useful for configuration default values, avoiding messy if-statements.

-Also a lovely [comune](http://en.wikipedia.org/wiki/Mergo) (municipality) in the Province of Ancona in the Italian region Marche.
-
-![Mergo dall'alto](http://www.comune.mergo.an.it/Siti/Mergo/Immagini/Foto/mergo_dall_alto.jpg)
+Also a lovely [comune](http://en.wikipedia.org/wiki/Mergo) (municipality) in the Province of Ancona in the Italian region of Marche.

 ## Status

-It is ready for production use. It works fine although it may use more of testing. Here some projects in the wild using Mergo:
+It is ready for production use. [It is used in several projects by Docker, Google, The Linux Foundation, VMWare, Shopify, etc](https://github.com/imdario/mergo#mergo-in-the-wild).

+[![GoDoc][3]][4]
+[![GoCard][5]][6]
+[![Build Status][1]][2]
+[![Coverage Status][7]][8]
+[![Sourcegraph][9]][10]
+
+[1]: https://travis-ci.org/imdario/mergo.png
+[2]: https://travis-ci.org/imdario/mergo
+[3]: https://godoc.org/github.com/imdario/mergo?status.svg
+[4]: https://godoc.org/github.com/imdario/mergo
+[5]: https://goreportcard.com/badge/imdario/mergo
+[6]: https://goreportcard.com/report/github.com/imdario/mergo
+[7]: https://coveralls.io/repos/github/imdario/mergo/badge.svg?branch=master
+[8]: https://coveralls.io/github/imdario/mergo?branch=master
+[9]: https://sourcegraph.com/github.com/imdario/mergo/-/badge.svg
+[10]: https://sourcegraph.com/github.com/imdario/mergo?badge
+
+### Latest release
+
+[Release v0.3.4](https://github.com/imdario/mergo/releases/tag/v0.3.4).
+
+### Important note
+
+Please keep in mind that in [0.3.2](//github.com/imdario/mergo/releases/tag/0.3.2) Mergo changed `Merge()`and `Map()` signatures to support [transformers](#transformers). An optional/variadic argument has been added, so it won't break existing code.
+
+If you were using Mergo **before** April 6th 2015, please check your project works as intended after updating your local copy with ```go get -u github.com/imdario/mergo```. I apologize for any issue caused by its previous behavior and any future bug that Mergo could cause (I hope it won't!) in existing projects after the change (release 0.2.0).
+
+### Donations
+
+If Mergo is useful to you, consider buying me a coffee, a beer or making a monthly donation so I can keep building great free software. :heart_eyes:
+
+<a href='https://ko-fi.com/B0B58839' target='_blank'><img height='36' style='border:0px;height:36px;' src='https://az743702.vo.msecnd.net/cdn/kofi1.png?v=0' border='0' alt='Buy Me a Coffee at ko-fi.com' /></a>
+[![Beerpay](https://beerpay.io/imdario/mergo/badge.svg)](https://beerpay.io/imdario/mergo)
+[![Beerpay](https://beerpay.io/imdario/mergo/make-wish.svg)](https://beerpay.io/imdario/mergo)
+<a href="https://liberapay.com/dario/donate"><img alt="Donate using Liberapay" src="https://liberapay.com/assets/widgets/donate.svg"></a>
+
+### Mergo in the wild
+
+- [moby/moby](https://github.com/moby/moby)
+- [kubernetes/kubernetes](https://github.com/kubernetes/kubernetes)
+- [vmware/dispatch](https://github.com/vmware/dispatch)
+- [Shopify/themekit](https://github.com/Shopify/themekit)
+- [imdario/zas](https://github.com/imdario/zas)
+- [matcornic/hermes](https://github.com/matcornic/hermes)
+- [OpenBazaar/openbazaar-go](https://github.com/OpenBazaar/openbazaar-go)
+- [kataras/iris](https://github.com/kataras/iris)
+- [michaelsauter/crane](https://github.com/michaelsauter/crane)
+- [go-task/task](https://github.com/go-task/task)
+- [sensu/uchiwa](https://github.com/sensu/uchiwa)
+- [ory/hydra](https://github.com/ory/hydra)
+- [sisatech/vcli](https://github.com/sisatech/vcli)
+- [dairycart/dairycart](https://github.com/dairycart/dairycart)
+- [projectcalico/felix](https://github.com/projectcalico/felix)
+- [resin-os/balena](https://github.com/resin-os/balena)
+- [go-kivik/kivik](https://github.com/go-kivik/kivik)
+- [Telefonica/govice](https://github.com/Telefonica/govice)
+- [supergiant/supergiant](supergiant/supergiant)
+- [SergeyTsalkov/brooce](https://github.com/SergeyTsalkov/brooce)
+- [soniah/dnsmadeeasy](https://github.com/soniah/dnsmadeeasy)
+- [ohsu-comp-bio/funnel](https://github.com/ohsu-comp-bio/funnel)
 - [EagerIO/Stout](https://github.com/EagerIO/Stout)
 - [lynndylanhurley/defsynth-api](https://github.com/lynndylanhurley/defsynth-api)
 - [russross/canvasassignments](https://github.com/russross/canvasassignments)
@ -17,12 +75,17 @@ It is ready for production use. It works fine although it may use more of testin
 - [casualjim/exeggutor](https://github.com/casualjim/exeggutor)
 - [divshot/gitling](https://github.com/divshot/gitling)
 - [RWJMurphy/gorl](https://github.com/RWJMurphy/gorl)
-
-[![Build Status][1]][2]
-[![GoDoc](https://godoc.org/github.com/imdario/mergo?status.svg)](https://godoc.org/github.com/imdario/mergo)
-
-[1]: https://travis-ci.org/imdario/mergo.png
-[2]: https://travis-ci.org/imdario/mergo
+- [andrerocker/deploy42](https://github.com/andrerocker/deploy42)
+- [elwinar/rambler](https://github.com/elwinar/rambler)
+- [tmaiaroto/gopartman](https://github.com/tmaiaroto/gopartman)
+- [jfbus/impressionist](https://github.com/jfbus/impressionist)
+- [Jmeyering/zealot](https://github.com/Jmeyering/zealot)
+- [godep-migrator/rigger-host](https://github.com/godep-migrator/rigger-host)
+- [Dronevery/MultiwaySwitch-Go](https://github.com/Dronevery/MultiwaySwitch-Go)
+- [thoas/picfit](https://github.com/thoas/picfit)
+- [mantasmatelis/whooplist-server](https://github.com/mantasmatelis/whooplist-server)
+- [jnuthong/item_search](https://github.com/jnuthong/item_search)
+- [bukalapak/snowboard](https://github.com/bukalapak/snowboard)

 ## Installation

@ -35,25 +98,116 @@ It is ready for production use. It works fine although it may use more of testin

 ## Usage

-You can only merge same-type structs with exported fields initialized as zero value of their type and same-types maps. Mergo won't merge unexported (private) fields but will do recursively any exported one. Also maps will be merged recursively except for structs inside maps (because they are not addressable using Go reflection).
+You can only merge same-type structs with exported fields initialized as zero value of their type and same-types maps. Mergo won't merge unexported (private) fields but will do recursively any exported one. It won't merge empty structs value as [they are not considered zero values](https://golang.org/ref/spec#The_zero_value) either. Also maps will be merged recursively except for structs inside maps (because they are not addressable using Go reflection).

-    if err := mergo.Merge(&dst, src); err != nil {
-        // ...
-    }
+```go
+if err := mergo.Merge(&dst, src); err != nil {
+    // ...
+}
+```

-Additionally, you can map a map[string]interface{} to a struct (and otherwise, from struct to map), following the same restrictions as in Merge(). Keys are capitalized to find each corresponding exported field.
+Also, you can merge overwriting values using the transformer `WithOverride`.

-    if err := mergo.Map(&dst, srcMap); err != nil {
-        // ...
-    }
+```go
+if err := mergo.Merge(&dst, src, mergo.WithOverride); err != nil {
+    // ...
+}
+```

-Warning: if you map a struct to map, it won't do it recursively. Don't expect Mergo to map struct members of your struct as map[string]interface{}. They will be just assigned as values.
+Additionally, you can map a `map[string]interface{}` to a struct (and otherwise, from struct to map), following the same restrictions as in `Merge()`. Keys are capitalized to find each corresponding exported field.
+
+```go
+if err := mergo.Map(&dst, srcMap); err != nil {
+    // ...
+}
+```
+
+Warning: if you map a struct to map, it won't do it recursively. Don't expect Mergo to map struct members of your struct as `map[string]interface{}`. They will be just assigned as values.

 More information and examples in [godoc documentation](http://godoc.org/github.com/imdario/mergo).

+### Nice example
+
+```go
+package main
+
+import (
+	"fmt"
+	"github.com/imdario/mergo"
+)
+
+type Foo struct {
+	A string
+	B int64
+}
+
+func main() {
+	src := Foo{
+		A: "one",
+		B: 2,
+	}
+	dest := Foo{
+		A: "two",
+	}
+	mergo.Merge(&dest, src)
+	fmt.Println(dest)
+	// Will print
+	// {two 2}
+}
+```
+
 Note: if test are failing due missing package, please execute:

-    go get gopkg.in/yaml.v1
+    go get gopkg.in/yaml.v2
+
+### Transformers
+
+Transformers allow to merge specific types differently than in the default behavior. In other words, now you can customize how some types are merged. For example, `time.Time` is a struct; it doesn't have zero value but IsZero can return true because it has fields with zero value. How can we merge a non-zero `time.Time`?
+
+```go
+package main
+
+import (
+	"fmt"
+	"github.com/imdario/mergo"
+        "reflect"
+        "time"
+)
+
+type timeTransfomer struct {
+}
+
+func (t timeTransfomer) Transformer(typ reflect.Type) func(dst, src reflect.Value) error {
+	if typ == reflect.TypeOf(time.Time{}) {
+		return func(dst, src reflect.Value) error {
+			if dst.CanSet() {
+				isZero := dst.MethodByName("IsZero")
+				result := isZero.Call([]reflect.Value{})
+				if result[0].Bool() {
+					dst.Set(src)
+				}
+			}
+			return nil
+		}
+	}
+	return nil
+}
+
+type Snapshot struct {
+	Time time.Time
+	// ...
+}
+
+func main() {
+	src := Snapshot{time.Now()}
+	dest := Snapshot{}
+	mergo.Merge(&dest, src, mergo.WithTransformers(timeTransfomer{}))
+	fmt.Println(dest)
+	// Will print
+	// { 2018-01-12 01:15:00 +0000 UTC m=+0.000000001 }
+}
+```
+

 ## Contact me

--- a/vendor/github.com/imdario/mergo/map.go
+++ b/vendor/github.com/imdario/mergo/map.go
@ -31,7 +31,8 @@ func isExported(field reflect.StructField) bool {
 // Traverses recursively both values, assigning src's fields values to dst.
 // The map argument tracks comparisons that have already been seen, which allows
 // short circuiting on recursive types.
-func deepMap(dst, src reflect.Value, visited map[uintptr]*visit, depth int) (err error) {
+func deepMap(dst, src reflect.Value, visited map[uintptr]*visit, depth int, config *Config) (err error) {
+	overwrite := config.Overwrite
 	if dst.CanAddr() {
 		addr := dst.UnsafeAddr()
 		h := 17 * addr
@ -57,10 +58,17 @@ func deepMap(dst, src reflect.Value, visited map[uintptr]*visit, depth int) (err
 			}
 			fieldName := field.Name
 			fieldName = changeInitialCase(fieldName, unicode.ToLower)
-			if v, ok := dstMap[fieldName]; !ok || isEmptyValue(reflect.ValueOf(v)) {
+			if v, ok := dstMap[fieldName]; !ok || (isEmptyValue(reflect.ValueOf(v)) || overwrite) {
 				dstMap[fieldName] = src.Field(i).Interface()
 			}
 		}
+	case reflect.Ptr:
+		if dst.IsNil() {
+			v := reflect.New(dst.Type().Elem())
+			dst.Set(v)
+		}
+		dst = dst.Elem()
+		fallthrough
 	case reflect.Struct:
 		srcMap := src.Interface().(map[string]interface{})
 		for key := range srcMap {
@ -85,21 +93,24 @@ func deepMap(dst, src reflect.Value, visited map[uintptr]*visit, depth int) (err
 					srcKind = reflect.Ptr
 				}
 			}
+
 			if !srcElement.IsValid() {
 				continue
 			}
 			if srcKind == dstKind {
-				if err = deepMerge(dstElement, srcElement, visited, depth+1); err != nil {
+				if err = deepMerge(dstElement, srcElement, visited, depth+1, config); err != nil {
+					return
+				}
+			} else if dstKind == reflect.Interface && dstElement.Kind() == reflect.Interface {
+				if err = deepMerge(dstElement, srcElement, visited, depth+1, config); err != nil {
+					return
+				}
+			} else if srcKind == reflect.Map {
+				if err = deepMap(dstElement, srcElement, visited, depth+1, config); err != nil {
 					return
 				}
 			} else {
-				if srcKind == reflect.Map {
-					if err = deepMap(dstElement, srcElement, visited, depth+1); err != nil {
-						return
-					}
-				} else {
-					return fmt.Errorf("type mismatch on %s field: found %v, expected %v", fieldName, srcKind, dstKind)
-				}
+				return fmt.Errorf("type mismatch on %s field: found %v, expected %v", fieldName, srcKind, dstKind)
 			}
 		}
 	}
@ -117,18 +128,35 @@ func deepMap(dst, src reflect.Value, visited map[uintptr]*visit, depth int) (err
 // doesn't apply if dst is a map.
 // This is separated method from Merge because it is cleaner and it keeps sane
 // semantics: merging equal types, mapping different (restricted) types.
-func Map(dst, src interface{}) error {
+func Map(dst, src interface{}, opts ...func(*Config)) error {
+	return _map(dst, src, opts...)
+}
+
+// MapWithOverwrite will do the same as Map except that non-empty dst attributes will be overridden by
+// non-empty src attribute values.
+// Deprecated: Use Map(…) with WithOverride
+func MapWithOverwrite(dst, src interface{}, opts ...func(*Config)) error {
+	return _map(dst, src, append(opts, WithOverride)...)
+}
+
+func _map(dst, src interface{}, opts ...func(*Config)) error {
 	var (
 		vDst, vSrc reflect.Value
 		err        error
 	)
+	config := &Config{}
+
+	for _, opt := range opts {
+		opt(config)
+	}
+
 	if vDst, vSrc, err = resolveValues(dst, src); err != nil {
 		return err
 	}
 	// To be friction-less, we redirect equal-type arguments
 	// to deepMerge. Only because arguments can be anything.
 	if vSrc.Kind() == vDst.Kind() {
-		return deepMerge(vDst, vSrc, make(map[uintptr]*visit), 0)
+		return deepMerge(vDst, vSrc, make(map[uintptr]*visit), 0, config)
 	}
 	switch vSrc.Kind() {
 	case reflect.Struct:
@ -142,5 +170,5 @@ func Map(dst, src interface{}) error {
 	default:
 		return ErrNotSupported
 	}
-	return deepMap(vDst, vSrc, make(map[uintptr]*visit), 0)
+	return deepMap(vDst, vSrc, make(map[uintptr]*visit), 0, config)
 }
--- a/vendor/github.com/imdario/mergo/merge.go
+++ b/vendor/github.com/imdario/mergo/merge.go
@ -12,10 +12,34 @@ import (
 	"reflect"
 )

+func hasExportedField(dst reflect.Value) (exported bool) {
+	for i, n := 0, dst.NumField(); i < n; i++ {
+		field := dst.Type().Field(i)
+		if field.Anonymous && dst.Field(i).Kind() == reflect.Struct {
+			exported = exported || hasExportedField(dst.Field(i))
+		} else {
+			exported = exported || len(field.PkgPath) == 0
+		}
+	}
+	return
+}
+
+type Config struct {
+	Overwrite    bool
+	AppendSlice  bool
+	Transformers Transformers
+}
+
+type Transformers interface {
+	Transformer(reflect.Type) func(dst, src reflect.Value) error
+}
+
 // Traverses recursively both values, assigning src's fields values to dst.
 // The map argument tracks comparisons that have already been seen, which allows
 // short circuiting on recursive types.
-func deepMerge(dst, src reflect.Value, visited map[uintptr]*visit, depth int) (err error) {
+func deepMerge(dst, src reflect.Value, visited map[uintptr]*visit, depth int, config *Config) (err error) {
+	overwrite := config.Overwrite
+
 	if !src.IsValid() {
 		return
 	}
@ -32,68 +56,190 @@ func deepMerge(dst, src reflect.Value, visited map[uintptr]*visit, depth int) (e
 		// Remember, remember...
 		visited[h] = &visit{addr, typ, seen}
 	}
+
+	if config.Transformers != nil && !isEmptyValue(dst) {
+		if fn := config.Transformers.Transformer(dst.Type()); fn != nil {
+			err = fn(dst, src)
+			return
+		}
+	}
+
 	switch dst.Kind() {
 	case reflect.Struct:
-		for i, n := 0, dst.NumField(); i < n; i++ {
-			if err = deepMerge(dst.Field(i), src.Field(i), visited, depth+1); err != nil {
-				return
+		if hasExportedField(dst) {
+			for i, n := 0, dst.NumField(); i < n; i++ {
+				if err = deepMerge(dst.Field(i), src.Field(i), visited, depth+1, config); err != nil {
+					return
+				}
+			}
+		} else {
+			if dst.CanSet() && !isEmptyValue(src) && (overwrite || isEmptyValue(dst)) {
+				dst.Set(src)
 			}
 		}
 	case reflect.Map:
+		if dst.IsNil() && !src.IsNil() {
+			dst.Set(reflect.MakeMap(dst.Type()))
+		}
 		for _, key := range src.MapKeys() {
 			srcElement := src.MapIndex(key)
 			if !srcElement.IsValid() {
 				continue
 			}
 			dstElement := dst.MapIndex(key)
-			switch reflect.TypeOf(srcElement.Interface()).Kind() {
-			case reflect.Struct:
+			switch srcElement.Kind() {
+			case reflect.Chan, reflect.Func, reflect.Map, reflect.Interface, reflect.Slice:
+				if srcElement.IsNil() {
+					continue
+				}
 				fallthrough
-			case reflect.Map:
-				if err = deepMerge(dstElement, srcElement, visited, depth+1); err != nil {
-					return
+			default:
+				if !srcElement.CanInterface() {
+					continue
+				}
+				switch reflect.TypeOf(srcElement.Interface()).Kind() {
+				case reflect.Struct:
+					fallthrough
+				case reflect.Ptr:
+					fallthrough
+				case reflect.Map:
+					srcMapElm := srcElement
+					dstMapElm := dstElement
+					if srcMapElm.CanInterface() {
+						srcMapElm = reflect.ValueOf(srcMapElm.Interface())
+						if dstMapElm.IsValid() {
+							dstMapElm = reflect.ValueOf(dstMapElm.Interface())
+						}
+					}
+					if err = deepMerge(dstMapElm, srcMapElm, visited, depth+1, config); err != nil {
+						return
+					}
+				case reflect.Slice:
+					srcSlice := reflect.ValueOf(srcElement.Interface())
+
+					var dstSlice reflect.Value
+					if !dstElement.IsValid() || dstElement.IsNil() {
+						dstSlice = reflect.MakeSlice(srcSlice.Type(), 0, srcSlice.Len())
+					} else {
+						dstSlice = reflect.ValueOf(dstElement.Interface())
+					}
+
+					if !isEmptyValue(src) && (overwrite || isEmptyValue(dst)) && !config.AppendSlice {
+						dstSlice = srcSlice
+					} else if config.AppendSlice {
+						dstSlice = reflect.AppendSlice(dstSlice, srcSlice)
+					}
+					dst.SetMapIndex(key, dstSlice)
 				}
 			}
-			if !dstElement.IsValid() {
+			if dstElement.IsValid() && reflect.TypeOf(srcElement.Interface()).Kind() == reflect.Map {
+				continue
+			}
+
+			if srcElement.IsValid() && (overwrite || (!dstElement.IsValid() || isEmptyValue(dstElement))) {
+				if dst.IsNil() {
+					dst.Set(reflect.MakeMap(dst.Type()))
+				}
 				dst.SetMapIndex(key, srcElement)
 			}
 		}
+	case reflect.Slice:
+		if !dst.CanSet() {
+			break
+		}
+		if !isEmptyValue(src) && (overwrite || isEmptyValue(dst)) && !config.AppendSlice {
+			dst.Set(src)
+		} else if config.AppendSlice {
+			dst.Set(reflect.AppendSlice(dst, src))
+		}
 	case reflect.Ptr:
 		fallthrough
 	case reflect.Interface:
 		if src.IsNil() {
 			break
-		} else if dst.IsNil() {
-			if dst.CanSet() && isEmptyValue(dst) {
+		}
+		if src.Kind() != reflect.Interface {
+			if dst.IsNil() || overwrite {
+				if dst.CanSet() && (overwrite || isEmptyValue(dst)) {
+					dst.Set(src)
+				}
+			} else if src.Kind() == reflect.Ptr {
+				if err = deepMerge(dst.Elem(), src.Elem(), visited, depth+1, config); err != nil {
+					return
+				}
+			} else if dst.Elem().Type() == src.Type() {
+				if err = deepMerge(dst.Elem(), src, visited, depth+1, config); err != nil {
+					return
+				}
+			} else {
+				return ErrDifferentArgumentsTypes
+			}
+			break
+		}
+		if dst.IsNil() || overwrite {
+			if dst.CanSet() && (overwrite || isEmptyValue(dst)) {
 				dst.Set(src)
 			}
-		} else if err = deepMerge(dst.Elem(), src.Elem(), visited, depth+1); err != nil {
+		} else if err = deepMerge(dst.Elem(), src.Elem(), visited, depth+1, config); err != nil {
 			return
 		}
 	default:
-		if dst.CanSet() && !isEmptyValue(src) {
+		if dst.CanSet() && !isEmptyValue(src) && (overwrite || isEmptyValue(dst)) {
 			dst.Set(src)
 		}
 	}
 	return
 }

-// Merge sets fields' values in dst from src if they have a zero
-// value of their type.
-// dst and src must be valid same-type structs and dst must be
-// a pointer to struct.
-// It won't merge unexported (private) fields and will do recursively
-// any exported field.
-func Merge(dst, src interface{}) error {
+// Merge will fill any empty for value type attributes on the dst struct using corresponding
+// src attributes if they themselves are not empty. dst and src must be valid same-type structs
+// and dst must be a pointer to struct.
+// It won't merge unexported (private) fields and will do recursively any exported field.
+func Merge(dst, src interface{}, opts ...func(*Config)) error {
+	return merge(dst, src, opts...)
+}
+
+// MergeWithOverwrite will do the same as Merge except that non-empty dst attributes will be overriden by
+// non-empty src attribute values.
+// Deprecated: use Merge(…) with WithOverride
+func MergeWithOverwrite(dst, src interface{}, opts ...func(*Config)) error {
+	return merge(dst, src, append(opts, WithOverride)...)
+}
+
+// WithTransformers adds transformers to merge, allowing to customize the merging of some types.
+func WithTransformers(transformers Transformers) func(*Config) {
+	return func(config *Config) {
+		config.Transformers = transformers
+	}
+}
+
+// WithOverride will make merge override non-empty dst attributes with non-empty src attributes values.
+func WithOverride(config *Config) {
+	config.Overwrite = true
+}
+
+// WithAppendSlice will make merge append slices instead of overwriting it
+func WithAppendSlice(config *Config) {
+	config.AppendSlice = true
+}
+
+func merge(dst, src interface{}, opts ...func(*Config)) error {
 	var (
 		vDst, vSrc reflect.Value
 		err        error
 	)
+
+	config := &Config{}
+
+	for _, opt := range opts {
+		opt(config)
+	}
+
 	if vDst, vSrc, err = resolveValues(dst, src); err != nil {
 		return err
 	}
 	if vDst.Type() != vSrc.Type() {
 		return ErrDifferentArgumentsTypes
 	}
-	return deepMerge(vDst, vSrc, make(map[uintptr]*visit), 0)
+	return deepMerge(vDst, vSrc, make(map[uintptr]*visit), 0, config)
 }
--- a/vendor/github.com/imdario/mergo/mergo.go
+++ b/vendor/github.com/imdario/mergo/mergo.go
@ -32,7 +32,7 @@ type visit struct {
 	next *visit
 }

-// From src/pkg/encoding/json.
+// From src/pkg/encoding/json/encode.go.
 func isEmptyValue(v reflect.Value) bool {
 	switch v.Kind() {
 	case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
@ -46,7 +46,14 @@ func isEmptyValue(v reflect.Value) bool {
 	case reflect.Float32, reflect.Float64:
 		return v.Float() == 0
 	case reflect.Interface, reflect.Ptr:
+		if v.IsNil() {
+			return true
+		}
+		return isEmptyValue(v.Elem())
+	case reflect.Func:
 		return v.IsNil()
+	case reflect.Invalid:
+		return true
 	}
 	return false
 }