Multiple providers in alpha config (#947)

* Initial commit of multiple provider logic:
1. Created new provider options.
2. Created legacy provider options and conversion options.
3. Added Providers to alpha Options.
4. Started Validation migration of multiple providers
5. Tests.

* fixed lint issues

* additional lint fixes

* Nits and alterations based on CR: manliy splitting large providers validation function and adding comments to provider options

* fixed typo

* removed weird : file

* small CR changes

* Removed GoogleGroups validation due to new allowed-groups (including tests). Added line in CHANGELOG

* Update pkg/apis/options/providers.go

Co-authored-by: Joel Speed <Joel.speed@hotmail.co.uk>

* Update pkg/apis/options/providers.go

Co-authored-by: Joel Speed <Joel.speed@hotmail.co.uk>

* Update pkg/apis/options/providers.go

Co-authored-by: Nick Meves <nick.meves@greenhouse.io>

* Initial commit of multiple provider logic:
1. Created new provider options.
2. Created legacy provider options and conversion options.
3. Added Providers to alpha Options.
4. Started Validation migration of multiple providers
5. Tests.

* fixed lint issues

* additional lint fixes

* Nits and alterations based on CR: manliy splitting large providers validation function and adding comments to provider options

* small CR changes

* auto generates alpha_config.md

* rebase (mainly service alpha options related conflicts)

* removed :

* Nits and alterations based on CR: manliy splitting large providers validation function and adding comments to provider options

* small CR changes

* Removed GoogleGroups validation due to new allowed-groups (including tests). Added line in CHANGELOG

* "cntd. rebase"

* ran make generate again

* last conflicts

* removed duplicate client id validation

* 1. Removed provider prefixes
2. altered optionsWithNilProvider logic
3. altered default provider logic
4. moved change in CHANELOG to 7.0.0

* fixed TestGoogleGroupOptions test

* ran make generate

* moved CHANGLOG line to 7.1.1

* moved changelog comment to 7.1.2 (additional rebase)

Co-authored-by: Yana Segal <yana.segal@nielsen.com>
Co-authored-by: Joel Speed <Joel.speed@hotmail.co.uk>
Co-authored-by: Nick Meves <nick.meves@greenhouse.io>

pkg/apis/options/load_test.go

@@ -14,6 +14,49 @@ import (
 )
 
 var _ = Describe("Load", func() {
+	optionsWithNilProvider := NewOptions()
+	optionsWithNilProvider.Providers = nil
+
+	legacyOptionsWithNilProvider := &LegacyOptions{
+		LegacyUpstreams: LegacyUpstreams{
+			PassHostHeader:  true,
+			ProxyWebSockets: true,
+			FlushInterval:   DefaultUpstreamFlushInterval,
+		},
+
+		LegacyHeaders: LegacyHeaders{
+			PassBasicAuth:        true,
+			PassUserHeaders:      true,
+			SkipAuthStripHeaders: true,
+		},
+
+		LegacyServer: LegacyServer{
+			HTTPAddress:  "127.0.0.1:4180",
+			HTTPSAddress: ":443",
+		},
+
+		LegacyProvider: LegacyProvider{
+			ProviderType:    "google",
+			AzureTenant:     "common",
+			ApprovalPrompt:  "force",
+			UserIDClaim:     "email",
+			OIDCEmailClaim:  "email",
+			OIDCGroupsClaim: "groups",
+		},
+
+		Options: Options{
+			ProxyPrefix:        "/oauth2",
+			PingPath:           "/ping",
+			RealClientIPHeader: "X-Real-IP",
+			ForceHTTPS:         false,
+			Cookie:             cookieDefaults(),
+			Session:            sessionOptionsDefaults(),
+			Templates:          templatesDefaults(),
+			SkipAuthPreflight:  false,
+			Logging:            loggingDefaults(),
+		},
+	}
+
 	Context("with a testOptions structure", func() {
 		type TestOptionSubStruct struct {
 			StringSliceOption []string `flag:"string-slice-option" cfg:"string_slice_option"`
@@ -294,12 +337,12 @@ var _ = Describe("Load", func() {
 			Entry("with an empty Options struct, should return default values", &testOptionsTableInput{
 				flagSet:        NewFlagSet,
 				input:          &Options{},
-				expectedOutput: NewOptions(),
+				expectedOutput: optionsWithNilProvider,
 			}),
 			Entry("with an empty LegacyOptions struct, should return default values", &testOptionsTableInput{
 				flagSet:        NewLegacyFlagSet,
 				input:          &LegacyOptions{},
-				expectedOutput: NewLegacyOptions(),
+				expectedOutput: legacyOptionsWithNilProvider,
 			}),
 		)
 	})