Add support for OPML export

Signed-off-by: AKP <tom@tdpain.net>

6 files changed, 101 insertions, 0 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index cb49c46..f8af81a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,8 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+* Support for OPML exports
 
 ## [0.1.0] - 2022-04-14
 Initial release
diff --git a/walrss/internal/core/feeds.go b/walrss/internal/core/feeds.go
index c9e4022..3aefd4c 100644
--- a/walrss/internal/core/feeds.go
+++ b/walrss/internal/core/feeds.go
@@ -2,6 +2,7 @@ package core
 
 import (
 	"errors"
+	"github.com/codemicro/walrss/walrss/internal/core/opml"
 	"github.com/codemicro/walrss/walrss/internal/db"
 	"github.com/codemicro/walrss/walrss/internal/state"
 	"github.com/lithammer/shortuuid/v4"
@@ -74,3 +75,15 @@ func UpdateFeed(st *state.State, feed *db.Feed) error {
 	}
 	return nil
 }
+
+func ExportFeedsForUser(st *state.State, userID string) ([]byte, error) {
+	var feeds []*db.Feed
+	user, err := GetUserByID(st, userID)
+	if err != nil {
+		return nil, err
+	}
+	if err := st.Data.Find(&feeds, bh.Where("UserID").Eq(userID)); err != nil {
+		return nil, err
+	}
+	return opml.FromFeeds(feeds, user.Email).ToBytes()
+}
diff --git a/walrss/internal/core/opml/opml.go b/walrss/internal/core/opml/opml.go
new file mode 100644
index 0000000..809a6b8
--- /dev/null
+++ b/walrss/internal/core/opml/opml.go
@@ -0,0 +1,60 @@
+package opml
+
+import (
+	"encoding/xml"
+	"github.com/codemicro/walrss/walrss/internal/db"
+	"time"
+)
+
+type OPML struct {
+	XMLName xml.Name `xml:"opml"`
+	Version string   `xml:"version,attr"`
+	Head    struct {
+		Title       string    `xml:"title"`
+		DateCreated time.Time `xml:"dateCreated,omitempty"`
+		OwnerEmail  string    `xml:"ownerEmail,omitempty"`
+	} `xml:"head"`
+	Body struct {
+		Outlines []*Outline `xml:"outline"`
+	} `xml:"body"`
+}
+
+// Outline holds all information about an outline.
+type Outline struct {
+	Outlines []*Outline `xml:"outline"`
+	Text     string     `xml:"text,attr"`
+	Title    string     `xml:"title,attr,omitempty"`
+	Type     string     `xml:"type,attr,omitempty"`
+	XMLURL   string     `xml:"xmlUrl,attr,omitempty"`
+}
+
+func FromBytes(x []byte) (*OPML, error) {
+	o := new(OPML)
+	if err := xml.Unmarshal(x, o); err != nil {
+		return nil, err
+	}
+	return o, nil
+}
+
+func (o *OPML) ToBytes() ([]byte, error) {
+	return xml.Marshal(o)
+}
+
+func FromFeeds(feeds []*db.Feed, userEmailAddress string) *OPML {
+	o := new(OPML)
+	o.Version = "2.0"
+	o.Head.Title = "Walrss feed export"
+	o.Head.OwnerEmail = userEmailAddress
+	o.Head.DateCreated = time.Now().UTC()
+
+	for _, feed := range feeds {
+		o.Body.Outlines = append(o.Body.Outlines, &Outline{
+			Text:   feed.Name,
+			Title:  feed.Name,
+			Type:   "rss",
+			XMLURL: feed.URL,
+		})
+	}
+
+	return o
+}
diff --git a/walrss/internal/http/exportImport.go b/walrss/internal/http/exportImport.go
new file mode 100644
index 0000000..89b2ecf
--- /dev/null
+++ b/walrss/internal/http/exportImport.go
@@ -0,0 +1,21 @@
+package http
+
+import (
+	"github.com/codemicro/walrss/walrss/internal/core"
+	"github.com/gofiber/fiber/v2"
+)
+
+func (s *Server) exportAsOPML(ctx *fiber.Ctx) error {
+	currentUserID := getCurrentUserID(ctx)
+	if currentUserID == "" {
+		return requestStandardSignIn(ctx)
+	}
+
+	exported, err := core.ExportFeedsForUser(s.state, currentUserID)
+	if err != nil {
+		return err
+	}
+
+	ctx.Set(fiber.HeaderContentType, "application/xml")
+	return ctx.Send(exported)
+}
diff --git a/walrss/internal/http/http.go b/walrss/internal/http/http.go
index 72a8634..295a91f 100644
--- a/walrss/internal/http/http.go
+++ b/walrss/internal/http/http.go
@@ -91,6 +91,8 @@ func (s *Server) registerHandlers() {
 
 	s.app.Post(urls.SendTestEmail, s.sendTestEmail)
 
+	s.app.Get(urls.ExportAsOPML, s.exportAsOPML)
+
 	s.app.Use(urls.Statics, static.NewHandler())
 }
 
diff --git a/walrss/internal/urls/urls.go b/walrss/internal/urls/urls.go
index 2edcc2e..835bbc7 100644
--- a/walrss/internal/urls/urls.go
+++ b/walrss/internal/urls/urls.go
@@ -18,6 +18,9 @@ const (
 	EditFeedItem       = Edit + "/feed/:id"
 	CancelEditFeedItem = Edit + "/feed/:id/cancel"
 
+	Export       = "/export"
+	ExportAsOPML = Export + "/opml"
+
 	New         = "/new"
 	NewFeedItem = New + "/feed"