Send mailing list emails

Signed-off-by: Sacha Al Himdani <sacha@getprobo.com>

pkg/server/mailactions/confirm.go

@@ -0,0 +1,124 @@
+// Copyright (c) 2025 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+package mailactions
+
+import (
+	"errors"
+	"html/template"
+	"net/http"
+	"net/url"
+
+	"go.probo.inc/probo/pkg/mailman"
+)
+
+func confirmGetHandler() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		token := r.URL.Query().Get("token")
+		if token == "" {
+			renderPage(
+				w,
+				http.StatusBadRequest,
+				page{
+					Title:   "Invalid link",
+					Heading: "Invalid link",
+					Body:    "This confirmation link is missing required information. Please use the link from your email.",
+				},
+			)
+			return
+		}
+
+		renderPage(
+			w,
+			http.StatusOK,
+			page{
+				Title:   "Confirm subscription",
+				Heading: "Confirm your subscription",
+				Body:    "Click the button below to confirm that you want to receive updates.",
+				Form: &form{
+					ActionURL: template.URL("?token=" + url.QueryEscape(token)),
+					Button:    "Confirm subscription",
+					Danger:    false,
+				},
+			},
+		)
+	}
+}
+
+func confirmPostHandler(mailmanSvc *mailman.Service, tokenSecret string) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		token := r.URL.Query().Get("token")
+		if token == "" {
+			renderPage(
+				w,
+				http.StatusBadRequest,
+				page{
+					Title:   "Invalid link",
+					Heading: "Invalid link",
+					Body:    "This confirmation link is missing required information. Please use the link from your email.",
+				},
+			)
+			return
+		}
+
+		data, err := mailman.ValidateConfirmToken(tokenSecret, token)
+		if err != nil {
+			renderPage(
+				w,
+				http.StatusUnauthorized,
+				page{
+					Title:   "Invalid link",
+					Heading: "Invalid or expired link",
+					Body:    "This confirmation link is invalid or has expired. Confirmation links are valid for 30 days — please re-subscribe to get a new one.",
+				},
+			)
+			return
+		}
+
+		if err := mailmanSvc.ConfirmSubscriberByEmail(r.Context(), data.MailingListID, data.Email); err != nil {
+			if errors.Is(err, mailman.ErrSubscriberNotFound) {
+				renderPage(
+					w,
+					http.StatusNotFound, page{
+						Title:   "Not found",
+						Heading: "Subscription not found",
+						Body:    "We could not find your subscription. It may have already been cancelled or this link was already used.",
+					},
+				)
+				return
+			}
+
+			renderPage(
+				w,
+				http.StatusInternalServerError,
+				page{
+					Title:   "Something went wrong",
+					Heading: "Something went wrong",
+					Body:    "We could not confirm your subscription. Please try again later.",
+				},
+			)
+			return
+		}
+
+		renderPage(
+			w,
+			http.StatusOK,
+			page{
+				Title:   "Subscription confirmed",
+				Heading: "Subscription confirmed",
+				Body:    "You're now subscribed and will receive updates.",
+			},
+		)
+	}
+}