feat(oauth,mastodon): mastodon instace selection and list fetching

.example.env

@@ -1,2 +1,3 @@
 TWITTER_CLIENT_ID=**********************************
 TWITTER_CLIENT_SECRET=**************************************************
+INSTANCES_SOCIAL_TOKEN=********************************************************************************************************************************

components/datalists_options.templ

@@ -0,0 +1,97 @@
+package components
+
+import (
+	"os"
+	"net/url"
+	"net/http"
+	"encoding/json"
+	"log"
+	"slices"
+	"extrovert/internals"
+	"fmt"
+	"errors"
+)
+
+type Instance struct {
+	Name string `json:"name"`
+}
+
+func fetchInstanceList(limit int) ([]Instance, error) {
+
+	u, err := url.ParseRequestURI("https://instances.social/api/1.0/instances/list")
+	if err != nil {
+		return []Instance{}, err
+	}
+
+	u.Query().Add("min_version", "0.1.0")
+	u.Query().Add("sort_by", "active_users")
+	u.Query().Add("count", fmt.Sprintf("%v", limit))
+	u.Query().Add("prohibted_content", "nudity_nocw")
+	u.Query().Add("prohibted_content", "pornography_nocw")
+	u.Query().Add("prohibted_content", "illegalContentLinks")
+	u.Query().Add("prohibted_content", "spam")
+	u.Query().Add("prohibted_content", "advertising")
+
+	req, err := http.NewRequest(http.MethodGet, u.String(), bytes.NewReader([]byte("")))
+	if err != nil {
+		return []Instance{}, err
+	}
+	req.Header.Add("Authorization", "Bearer "+os.Getenv("INSTANCES_SOCIAL_TOKEN"))
+
+	res, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return []Instance{}, err
+	}
+
+	body, err := io.ReadAll(res.Body)
+	if err != nil {
+		return []Instance{}, err
+	} else if res.StatusCode != 200 {
+		return []Instance{}, errors.New(string(body))
+	}
+
+	var list struct {
+		Instances []Instance `json:"instances"`
+	}
+	err = json.Unmarshal(body, &list)
+
+	return list.Instances, err
+}
+
+var INSTANCES = []Instance{
+	/*
+		These servers are not endorsed, curated or affiliated by Capytal in any way, shape
+		or form. All the instances where got from the top 15 listed in https://joinmastodon.org/servers,
+		at July 8th, 2024 (2024-07-08).
+	*/
+	{Name: "mastodon.social"},
+	{Name: "mstdn.social"},
+	{Name: "mas.to"},
+	{Name: "social.vivaldi.net"},
+	{Name: "mastodonapp.uk"},
+	{Name: "universeodon.com"},
+	{Name: "c.im"},
+	{Name: "mstdn.party"},
+	{Name: "toot.community"},
+	{Name: "ohai.social"},
+	{Name: "mstdn.business"},
+	{Name: "ieji.de"},
+	{Name: "toot.io"},
+	{Name: "masto.nu"},
+	{Name: "mstdn.plus"},
+}
+
+func getInstanceList(limit int) []Instance {
+	i, err := fetchInstanceList(limit)
+	if err != nil {
+		log.Printf("WARN: Unable to fetch Mastodon instance datalist due to:\n%s\n\nFall backing into static list.", err.Error())
+		return INSTANCES
+	}
+	return internals.RemoveDuplicates(slices.Concat(INSTANCES, i))
+}
+
+templ InstancesOptions(limit int) {
+	for _, v := range getInstanceList(limit) {
+		<option value={ v.Name }></option>
+	}
+}

components/logins.templ

@@ -21,3 +21,32 @@ var loginUrl = fmt.Sprintf("https://x.com/i/oauth2/authorize"+
 templ LoginTwitter() {
 	<a href={ templ.SafeURL(loginUrl) } rel="">Login on Twitter</a>
 }
+
+templ LoginMastodon() {
+	<button popovertargetaction="show" popovertarget="mastodon-login">Login on Mastodon</button>
+	<div id="mastodon-login" popover>
+		<dialog open>
+			<article>
+				<header>
+					<button
+						popovertargetaction="hide"
+						popovertarget="mastodon-login"
+						aria-label="Close"
+						rel="prev"
+					></button>
+					<label for="instance-url">Choose a instance</label>
+				</header>
+				<input
+					type="url"
+					name="instance-url"
+					placeholder="Instance Url"
+					aria-label="Instance Url"
+					list="instance-suggestions"
+				/>
+				<datalist id="instance-suggestions">
+					@InstancesOptions(20)
+				</datalist>
+			</article>
+		</dialog>
+	</div>
+}

internals/helpers.go

@@ -6,6 +6,18 @@ import (
 	"slices"
 )
 
+func RemoveDuplicates[T comparable](slice []T) []T {
+	keys := make(map[T]bool)
+	list := []T{}
+	for _, entry := range slice {
+		if _, value := keys[entry]; !value {
+			keys[entry] = true
+			list = append(list, entry)
+		}
+	}
+	return list
+}
+
 func GetCookie(name string, w http.ResponseWriter, r *http.Request) *http.Cookie {
 	name = fmt.Sprintf("__Host-%s-%s-%s", APP_NAME, APP_VERSION, name)
 

routes/index.templ

@@ -21,13 +21,13 @@ templ IndexPage() {
 				<main
 					style="height:15rem"
 				>
-					<form
+					<aside
 						style="height:100%;display:flex;gap:2rem;"
 					>
-						<fieldset style="display:flex;flex-direction:column;gap:1rem;width:15rem;">
+						<div style="display:flex;flex-direction:column;gap:1rem;width:15rem;">
 							@components.LoginTwitter()
-							<button>Login on Mastodon</button>
+							@components.LoginMastodon()
-						</fieldset>
+						</div>
 						<fieldset>
 							<textarea
 								style="height:100%;resize:none;"
@@ -36,7 +36,7 @@ templ IndexPage() {
 								aria-label="Post input"
 							></textarea>
 						</fieldset>
-					</form>
+					</aside>
 				</main>
 				<footer>
 					@components.Warning("In Development") {

routes/mastodon_login.templ

@@ -0,0 +1,98 @@
+package routes
+
+import (
+	"net/http"
+	"fmt"
+	"encoding/json"
+	"errors"
+	"os"
+
+	"extrovert/layouts"
+	"extrovert/internals"
+	"log"
+)
+
+type MastodonTokenResponse struct {
+	Type    string `json:"token_type"`
+	Token   string `json:"access_token"`
+	Expires int    `json:"expires_in"`
+	Scope   string `json:"scope"`
+}
+
+func MastodonLoginHandler(w http.ResponseWriter, r *http.Request) {
+	error := internals.HttpErrorHelper(w)
+
+	code := r.URL.Query().Get("code")
+	if code == "" {
+		error(
+			"Bad request",
+			errors.New("Missing \"code\" parameter"),
+			http.StatusBadRequest,
+		)
+		return
+	}
+
+	tReq := fmt.Sprintf("https://api.twitter.com/2/oauth2/token"+
+		"?grant_type=authorization_code"+
+		"&client_id=%s"+
+		"&code_verifier=challenge"+
+		"&code=%s"+
+		"&challenge_method=plain"+
+		"&redirect_uri=http://localhost:7331/api/oauth/twitter",
+		os.Getenv("TWITTER_CLIENT_ID"),
+		code,
+	)
+
+	t, err := http.Post(tReq, "application/x-www-form-urlencoded", bytes.NewReader([]byte("")))
+	if error("Error trying to request token from twitter", err, http.StatusInternalServerError) {
+		return
+	}
+
+	b, err := io.ReadAll(t.Body)
+	if error("Error trying to read response body from twitter", err, http.StatusInternalServerError) {
+		return
+	} else if t.StatusCode < 200 || t.StatusCode > 299 {
+		error(
+			"Error trying to request token from twitter, returned non-200 code",
+			errors.New(fmt.Sprintf("Code: %v, Return value: %s", t.StatusCode, string(b))),
+			http.StatusInternalServerError,
+		)
+		return
+	}
+
+	var res TwitterTokenResponse
+	err = json.Unmarshal(b, &res)
+	if error("Error trying to parse response body from twitter", err, http.StatusInternalServerError) {
+		return
+	}
+
+	log.Print(res)
+
+	c := internals.GetCookie("twitter-data", w, r)
+	c.Value = res.Token
+	http.SetCookie(w, c)
+
+	MastodonLogin().Render(context.Background(), w)
+}
+
+templ MastodonLogin() {
+	@layouts.Page("Project Extrovert") {
+		<dialog open>
+			<article>
+				<header>
+					<p>Logged into Twitter!</p>
+				</header>
+				<p>
+					Your account was succefully connected with project-extrovert!
+					Click "Ok" to return to the index page.
+				</p>
+				<footer>
+					<a href="/index.html">
+						<button>Ok</button>
+					</a>
+				</footer>
+			</article>
+		</dialog>
+		@IndexPage()
+	}
+}