Add OAuth2 integration example, have fun! https://github.com/iris-contrib/community-board/issues/4

Former-commit-id: e4f9dfbdfe16c9ca1ad84ac5a844a5d060fb3b5e

README.md

@@ -163,7 +163,7 @@ $ rizla main.go
 <details>
 <summary>Legends</summary>
 
-I'm sorry for taking this personally but I really need to thanks each one of them because they stood up [♡](https://github.com/kataras/iris#support) for me when others trying to "bullying" my personality in order to deflame Iris. 
+I'm sorry for taking this personally but I really need to thank each one of them because they stood up [♡](https://github.com/kataras/iris#support) for me when others tried to "bullying" my personality in order to deflame Iris.
 
 All of us should read and respect the official [golang](https://golang.org/conduct) and [iris](https://github.com/iris-contrib/community-board/blob/master/CODE-OF-CONDUCT.md) community **Code of Conduct**. This type of commitment and communication is the way of making Go great.
 

_examples/README.md

@@ -44,6 +44,7 @@ It doesn't contains "best ways" neither explains all its features. It's just a s
     * [Request Logger](beginner/request-logger/main.go)
     * [Basic Authentication](beginner/basicauth/main.go)
 * [Level: Intermediate](intermediate)
+    * [OAUth2](intermediate/oauth2/main.go)
     * [Transactions](intermediate/transactions/main.go)
     * [HTTP Testing](intermediate/httptest/main_test.go)
     * [Watch & Compile Typescript source files](intermediate/typescript/main.go)

_examples/intermediate/oauth2/main.go

@@ -0,0 +1,409 @@
+package main
+
+// Any OAuth2 (even the pure golang/x/net/oauth2) package
+// can be used with Iris but at this example we will see the markbates' goth:
+//
+// $ go get github.com/markbates/goth/...
+//
+// This OAuth2 example works with sessions, so we will need
+// to attach a session manager.
+// Optionally: for even more secure session values,
+// developers can use any third-party package to add a custom cookie encoder/decoder.
+// At this example we will use the gorilla's securecookie:
+//
+// $ go get github.com/gorilla/securecookie
+// Example of securecookie can be found at "sessions/securecookie" example folder.
+
+// Notes:
+// The whole example is converted by markbates/goth/example/main.go.
+// It's tested with my own TWITTER application and it worked, even for localhost.
+// I guess that everything else works as expected, all bugs reported by goth library's community
+// are fixed in the time I wrote that example, have fun!
+import (
+	"errors"
+	"os"
+	"sort"
+
+	"github.com/kataras/iris"
+	"github.com/kataras/iris/context"
+	"github.com/kataras/iris/sessions"
+	"github.com/kataras/iris/view"
+
+	"github.com/gorilla/securecookie" // optionally, used for session's encoder/decoder
+
+	"github.com/markbates/goth"
+	"github.com/markbates/goth/providers/amazon"
+	"github.com/markbates/goth/providers/auth0"
+	"github.com/markbates/goth/providers/bitbucket"
+	"github.com/markbates/goth/providers/box"
+	"github.com/markbates/goth/providers/dailymotion"
+	"github.com/markbates/goth/providers/deezer"
+	"github.com/markbates/goth/providers/digitalocean"
+	"github.com/markbates/goth/providers/discord"
+	"github.com/markbates/goth/providers/dropbox"
+	"github.com/markbates/goth/providers/facebook"
+	"github.com/markbates/goth/providers/fitbit"
+	"github.com/markbates/goth/providers/github"
+	"github.com/markbates/goth/providers/gitlab"
+	"github.com/markbates/goth/providers/gplus"
+	"github.com/markbates/goth/providers/heroku"
+	"github.com/markbates/goth/providers/instagram"
+	"github.com/markbates/goth/providers/intercom"
+	"github.com/markbates/goth/providers/lastfm"
+	"github.com/markbates/goth/providers/linkedin"
+	"github.com/markbates/goth/providers/meetup"
+	"github.com/markbates/goth/providers/onedrive"
+	"github.com/markbates/goth/providers/openidConnect"
+	"github.com/markbates/goth/providers/paypal"
+	"github.com/markbates/goth/providers/salesforce"
+	"github.com/markbates/goth/providers/slack"
+	"github.com/markbates/goth/providers/soundcloud"
+	"github.com/markbates/goth/providers/spotify"
+	"github.com/markbates/goth/providers/steam"
+	"github.com/markbates/goth/providers/stripe"
+	"github.com/markbates/goth/providers/twitch"
+	"github.com/markbates/goth/providers/twitter"
+	"github.com/markbates/goth/providers/uber"
+	"github.com/markbates/goth/providers/wepay"
+	"github.com/markbates/goth/providers/xero"
+	"github.com/markbates/goth/providers/yahoo"
+	"github.com/markbates/goth/providers/yammer"
+)
+
+// These are some function helpers that you may use if you want
+
+// GetProviderName is a function used to get the name of a provider
+// for a given request. By default, this provider is fetched from
+// the URL query string. If you provide it in a different way,
+// assign your own function to this variable that returns the provider
+// name for your request.
+var GetProviderName = func(ctx context.Context) (string, error) {
+	// try to get it from the url param "provider"
+	if p := ctx.URLParam("provider"); p != "" {
+		return p, nil
+	}
+
+	// try to get it from the url PATH parameter "{provider} or :provider or {provider:string} or {provider:alphabetical}"
+	if p := ctx.Params().Get("provider"); p != "" {
+		return p, nil
+	}
+
+	// try to get it from context's per-request storage
+	if p := ctx.Values().GetString("provider"); p != "" {
+		return p, nil
+	}
+	// if not found then return an empty string with the corresponding error
+	return "", errors.New("you must select a provider")
+}
+
+/*
+BeginAuthHandler is a convienence handler for starting the authentication process.
+It expects to be able to get the name of the provider from the query parameters
+as either "provider" or ":provider".
+
+BeginAuthHandler will redirect the user to the appropriate authentication end-point
+for the requested provider.
+
+See https://github.com/markbates/goth/examples/main.go to see this in action.
+*/
+func BeginAuthHandler(ctx context.Context) {
+	url, err := GetAuthURL(ctx)
+	if err != nil {
+		ctx.StatusCode(iris.StatusBadRequest)
+		ctx.Writef("%v", err)
+		return
+	}
+
+	ctx.Redirect(url, iris.StatusTemporaryRedirect)
+}
+
+/*
+GetAuthURL starts the authentication process with the requested provided.
+It will return a URL that should be used to send users to.
+
+It expects to be able to get the name of the provider from the query parameters
+as either "provider" or ":provider" or from the context's value of "provider" key.
+
+I would recommend using the BeginAuthHandler instead of doing all of these steps
+yourself, but that's entirely up to you.
+*/
+func GetAuthURL(ctx context.Context) (string, error) {
+	providerName, err := GetProviderName(ctx)
+	if err != nil {
+		return "", err
+	}
+
+	provider, err := goth.GetProvider(providerName)
+	if err != nil {
+		return "", err
+	}
+	sess, err := provider.BeginAuth(SetState(ctx))
+	if err != nil {
+		return "", err
+	}
+
+	url, err := sess.GetAuthURL()
+	if err != nil {
+		return "", err
+	}
+
+	ctx.Session().Set(providerName, sess.Marshal())
+	return url, nil
+}
+
+// SetState sets the state string associated with the given request.
+// If no state string is associated with the request, one will be generated.
+// This state is sent to the provider and can be retrieved during the
+// callback.
+var SetState = func(ctx context.Context) string {
+	state := ctx.URLParam("state")
+	if len(state) > 0 {
+		return state
+	}
+
+	return "state"
+
+}
+
+// GetState gets the state returned by the provider during the callback.
+// This is used to prevent CSRF attacks, see
+// http://tools.ietf.org/html/rfc6749#section-10.12
+var GetState = func(ctx context.Context) string {
+	return ctx.URLParam("state")
+}
+
+/*
+CompleteUserAuth does what it says on the tin. It completes the authentication
+process and fetches all of the basic information about the user from the provider.
+
+It expects to be able to get the name of the provider from the query parameters
+as either "provider" or ":provider".
+
+See https://github.com/markbates/goth/examples/main.go to see this in action.
+*/
+var CompleteUserAuth = func(ctx context.Context) (goth.User, error) {
+	providerName, err := GetProviderName(ctx)
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	provider, err := goth.GetProvider(providerName)
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	value := ctx.Session().GetString(providerName)
+	if value == "" {
+		return goth.User{}, errors.New("session value for " + providerName + " not found")
+	}
+
+	sess, err := provider.UnmarshalSession(value)
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	user, err := provider.FetchUser(sess)
+	if err == nil {
+		// user can be found with existing session data
+		return user, err
+	}
+
+	// get new token and retry fetch
+	_, err = sess.Authorize(provider, ctx.Request().URL.Query())
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	ctx.Session().Set(providerName, sess.Marshal())
+	return provider.FetchUser(sess)
+}
+
+// Logout invalidates a user session.
+func Logout(ctx context.Context) error {
+	providerName, err := GetProviderName(ctx)
+	if err != nil {
+		return err
+	}
+
+	ctx.Session().Delete(providerName)
+	return nil
+}
+
+// End of the "some function helpers".
+
+func main() {
+	goth.UseProviders(
+		twitter.New(os.Getenv("TWITTER_KEY"), os.Getenv("TWITTER_SECRET"), "http://localhost:3000/auth/twitter/callback"),
+		// If you'd like to use authenticate instead of authorize in Twitter provider, use this instead.
+		// twitter.NewAuthenticate(os.Getenv("TWITTER_KEY"), os.Getenv("TWITTER_SECRET"), "http://localhost:3000/auth/twitter/callback"),
+
+		facebook.New(os.Getenv("FACEBOOK_KEY"), os.Getenv("FACEBOOK_SECRET"), "http://localhost:3000/auth/facebook/callback"),
+		fitbit.New(os.Getenv("FITBIT_KEY"), os.Getenv("FITBIT_SECRET"), "http://localhost:3000/auth/fitbit/callback"),
+		gplus.New(os.Getenv("GPLUS_KEY"), os.Getenv("GPLUS_SECRET"), "http://localhost:3000/auth/gplus/callback"),
+		github.New(os.Getenv("GITHUB_KEY"), os.Getenv("GITHUB_SECRET"), "http://localhost:3000/auth/github/callback"),
+		spotify.New(os.Getenv("SPOTIFY_KEY"), os.Getenv("SPOTIFY_SECRET"), "http://localhost:3000/auth/spotify/callback"),
+		linkedin.New(os.Getenv("LINKEDIN_KEY"), os.Getenv("LINKEDIN_SECRET"), "http://localhost:3000/auth/linkedin/callback"),
+		lastfm.New(os.Getenv("LASTFM_KEY"), os.Getenv("LASTFM_SECRET"), "http://localhost:3000/auth/lastfm/callback"),
+		twitch.New(os.Getenv("TWITCH_KEY"), os.Getenv("TWITCH_SECRET"), "http://localhost:3000/auth/twitch/callback"),
+		dropbox.New(os.Getenv("DROPBOX_KEY"), os.Getenv("DROPBOX_SECRET"), "http://localhost:3000/auth/dropbox/callback"),
+		digitalocean.New(os.Getenv("DIGITALOCEAN_KEY"), os.Getenv("DIGITALOCEAN_SECRET"), "http://localhost:3000/auth/digitalocean/callback", "read"),
+		bitbucket.New(os.Getenv("BITBUCKET_KEY"), os.Getenv("BITBUCKET_SECRET"), "http://localhost:3000/auth/bitbucket/callback"),
+		instagram.New(os.Getenv("INSTAGRAM_KEY"), os.Getenv("INSTAGRAM_SECRET"), "http://localhost:3000/auth/instagram/callback"),
+		intercom.New(os.Getenv("INTERCOM_KEY"), os.Getenv("INTERCOM_SECRET"), "http://localhost:3000/auth/intercom/callback"),
+		box.New(os.Getenv("BOX_KEY"), os.Getenv("BOX_SECRET"), "http://localhost:3000/auth/box/callback"),
+		salesforce.New(os.Getenv("SALESFORCE_KEY"), os.Getenv("SALESFORCE_SECRET"), "http://localhost:3000/auth/salesforce/callback"),
+		amazon.New(os.Getenv("AMAZON_KEY"), os.Getenv("AMAZON_SECRET"), "http://localhost:3000/auth/amazon/callback"),
+		yammer.New(os.Getenv("YAMMER_KEY"), os.Getenv("YAMMER_SECRET"), "http://localhost:3000/auth/yammer/callback"),
+		onedrive.New(os.Getenv("ONEDRIVE_KEY"), os.Getenv("ONEDRIVE_SECRET"), "http://localhost:3000/auth/onedrive/callback"),
+
+		//Pointed localhost.com to http://localhost:3000/auth/yahoo/callback through proxy as yahoo
+		// does not allow to put custom ports in redirection uri
+		yahoo.New(os.Getenv("YAHOO_KEY"), os.Getenv("YAHOO_SECRET"), "http://localhost.com"),
+		slack.New(os.Getenv("SLACK_KEY"), os.Getenv("SLACK_SECRET"), "http://localhost:3000/auth/slack/callback"),
+		stripe.New(os.Getenv("STRIPE_KEY"), os.Getenv("STRIPE_SECRET"), "http://localhost:3000/auth/stripe/callback"),
+		wepay.New(os.Getenv("WEPAY_KEY"), os.Getenv("WEPAY_SECRET"), "http://localhost:3000/auth/wepay/callback", "view_user"),
+		//By default paypal production auth urls will be used, please set PAYPAL_ENV=sandbox as environment variable for testing
+		//in sandbox environment
+		paypal.New(os.Getenv("PAYPAL_KEY"), os.Getenv("PAYPAL_SECRET"), "http://localhost:3000/auth/paypal/callback"),
+		steam.New(os.Getenv("STEAM_KEY"), "http://localhost:3000/auth/steam/callback"),
+		heroku.New(os.Getenv("HEROKU_KEY"), os.Getenv("HEROKU_SECRET"), "http://localhost:3000/auth/heroku/callback"),
+		uber.New(os.Getenv("UBER_KEY"), os.Getenv("UBER_SECRET"), "http://localhost:3000/auth/uber/callback"),
+		soundcloud.New(os.Getenv("SOUNDCLOUD_KEY"), os.Getenv("SOUNDCLOUD_SECRET"), "http://localhost:3000/auth/soundcloud/callback"),
+		gitlab.New(os.Getenv("GITLAB_KEY"), os.Getenv("GITLAB_SECRET"), "http://localhost:3000/auth/gitlab/callback"),
+		dailymotion.New(os.Getenv("DAILYMOTION_KEY"), os.Getenv("DAILYMOTION_SECRET"), "http://localhost:3000/auth/dailymotion/callback", "email"),
+		deezer.New(os.Getenv("DEEZER_KEY"), os.Getenv("DEEZER_SECRET"), "http://localhost:3000/auth/deezer/callback", "email"),
+		discord.New(os.Getenv("DISCORD_KEY"), os.Getenv("DISCORD_SECRET"), "http://localhost:3000/auth/discord/callback", discord.ScopeIdentify, discord.ScopeEmail),
+		meetup.New(os.Getenv("MEETUP_KEY"), os.Getenv("MEETUP_SECRET"), "http://localhost:3000/auth/meetup/callback"),
+
+		//Auth0 allocates domain per customer, a domain must be provided for auth0 to work
+		auth0.New(os.Getenv("AUTH0_KEY"), os.Getenv("AUTH0_SECRET"), "http://localhost:3000/auth/auth0/callback", os.Getenv("AUTH0_DOMAIN")),
+		xero.New(os.Getenv("XERO_KEY"), os.Getenv("XERO_SECRET"), "http://localhost:3000/auth/xero/callback"),
+	)
+
+	// OpenID Connect is based on OpenID Connect Auto Discovery URL (https://openid.net/specs/openid-connect-discovery-1_0-17.html)
+	// because the OpenID Connect provider initialize it self in the New(), it can return an error which should be handled or ignored
+	// ignore the error for now
+	openidConnect, _ := openidConnect.New(os.Getenv("OPENID_CONNECT_KEY"), os.Getenv("OPENID_CONNECT_SECRET"), "http://localhost:3000/auth/openid-connect/callback", os.Getenv("OPENID_CONNECT_DISCOVERY_URL"))
+	if openidConnect != nil {
+		goth.UseProviders(openidConnect)
+	}
+
+	m := make(map[string]string)
+	m["amazon"] = "Amazon"
+	m["bitbucket"] = "Bitbucket"
+	m["box"] = "Box"
+	m["dailymotion"] = "Dailymotion"
+	m["deezer"] = "Deezer"
+	m["digitalocean"] = "Digital Ocean"
+	m["discord"] = "Discord"
+	m["dropbox"] = "Dropbox"
+	m["facebook"] = "Facebook"
+	m["fitbit"] = "Fitbit"
+	m["github"] = "Github"
+	m["gitlab"] = "Gitlab"
+	m["soundcloud"] = "SoundCloud"
+	m["spotify"] = "Spotify"
+	m["steam"] = "Steam"
+	m["stripe"] = "Stripe"
+	m["twitch"] = "Twitch"
+	m["uber"] = "Uber"
+	m["wepay"] = "Wepay"
+	m["yahoo"] = "Yahoo"
+	m["yammer"] = "Yammer"
+	m["gplus"] = "Google Plus"
+	m["heroku"] = "Heroku"
+	m["instagram"] = "Instagram"
+	m["intercom"] = "Intercom"
+	m["lastfm"] = "Last FM"
+	m["linkedin"] = "Linkedin"
+	m["onedrive"] = "Onedrive"
+	m["paypal"] = "Paypal"
+	m["twitter"] = "Twitter"
+	m["salesforce"] = "Salesforce"
+	m["slack"] = "Slack"
+	m["meetup"] = "Meetup.com"
+	m["auth0"] = "Auth0"
+	m["openid-connect"] = "OpenID Connect"
+	m["xero"] = "Xero"
+
+	var keys []string
+	for k := range m {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+
+	providerIndex := &ProviderIndex{Providers: keys, ProvidersMap: m}
+
+	// create our app,
+	// set a view
+	// set sessions
+	// and setup the router for the showcase
+	app := iris.New()
+
+	// attach and build our templates
+	app.AttachView(view.HTML("./templates", ".html"))
+
+	// attach a session manager
+	cookieName := "mycustomsessionid"
+	// AES only supports key sizes of 16, 24 or 32 bytes.
+	// You either need to provide exactly that amount or you derive the key from what you type in.
+	hashKey := []byte("the-big-and-secret-fash-key-here")
+	blockKey := []byte("lot-secret-of-characters-big-too")
+	secureCookie := securecookie.New(hashKey, blockKey)
+	sessManager := sessions.New(sessions.Config{
+		Cookie: cookieName,
+		Encode: secureCookie.Encode,
+		Decode: secureCookie.Decode,
+	})
+	app.AttachSessionManager(sessManager)
+
+	// start of the router
+
+	app.Get("/auth/{provider}/callback", func(ctx context.Context) {
+
+		user, err := CompleteUserAuth(ctx)
+		if err != nil {
+			ctx.StatusCode(iris.StatusInternalServerError)
+			ctx.Writef("%v", err)
+			return
+		}
+		ctx.ViewData("", user)
+		if err := ctx.View("user.html"); err != nil {
+			ctx.Writef("%v", err)
+		}
+	})
+
+	app.Get("/logout/{provider}", func(ctx context.Context) {
+		Logout(ctx)
+		ctx.Redirect("/", iris.StatusTemporaryRedirect)
+	})
+
+	app.Get("/auth/{provider}", func(ctx context.Context) {
+		// try to get the user without re-authenticating
+		if gothUser, err := CompleteUserAuth(ctx); err == nil {
+			ctx.ViewData("", gothUser)
+			if err := ctx.View("user.html"); err != nil {
+				ctx.Writef("%v", err)
+			}
+		} else {
+			BeginAuthHandler(ctx)
+		}
+	})
+
+	app.Get("/", func(ctx context.Context) {
+
+		ctx.ViewData("", providerIndex)
+
+		if err := ctx.View("index.html"); err != nil {
+			ctx.Writef("%v", err)
+		}
+	})
+
+	// http://localhost:3000
+	app.Run(iris.Addr("localhost:3000"))
+}
+
+type ProviderIndex struct {
+	Providers    []string
+	ProvidersMap map[string]string
+}

_examples/intermediate/oauth2/templates/index.html

@@ -0,0 +1,3 @@
+{{range $key,$value:=.Providers}}
+    <p><a href="/auth/{{$value}}">Log in with {{index $.ProvidersMap $value}}</a></p>
+{{end}}

_examples/intermediate/oauth2/templates/user.html

@@ -0,0 +1,11 @@
+<p><a href="/logout/{{.Provider}}">logout</a></p>
+<p>Name: {{.Name}} [{{.LastName}}, {{.FirstName}}]</p>
+<p>Email: {{.Email}}</p>
+<p>NickName: {{.NickName}}</p>
+<p>Location: {{.Location}}</p>
+<p>AvatarURL: {{.AvatarURL}} <img src="{{.AvatarURL}}"></p>
+<p>Description: {{.Description}}</p>
+<p>UserID: {{.UserID}}</p>
+<p>AccessToken: {{.AccessToken}}</p>
+<p>ExpiresAt: {{.ExpiresAt}}</p>
+<p>RefreshToken: {{.RefreshToken}}</p>

_examples/intermediate/sessions/securecookie/main.go

@@ -1,13 +1,16 @@
 package main
 
-import (
+// developers can use any library to add a custom cookie encoder/decoder.
-	// developers can use any library to add a custom cookie encoder/decoder.
+// At this example we use the gorilla's securecookie package:
-	// At this example we use the gorilla's securecookie library:
+// $ go get github.com/gorilla/securecookie
-	"github.com/gorilla/securecookie"
+// $ go run main.go
 
+import (
 	"github.com/kataras/iris"
 	"github.com/kataras/iris/context"
 	"github.com/kataras/iris/sessions"
+
+	"github.com/gorilla/securecookie"
 )
 
 func main() {