[feature] Implement markers API (#1989)

* Implement markers API

Fixes #1856

* Correct import grouping in markers files

* Regenerate Swagger for markers API

* Shorten names for readability

* Cache markers for 6 hours

* Update DB ref

* Update envparsing.sh

5 files changed, 311 insertions, 3 deletions

diff --git a/internal/api/client.go b/internal/api/client.go
index d9f131e3b..e91ee2d2c 100644
--- a/internal/api/client.go
+++ b/internal/api/client.go
@@ -33,6 +33,7 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/api/client/followrequests"
 	"github.com/superseriousbusiness/gotosocial/internal/api/client/instance"
 	"github.com/superseriousbusiness/gotosocial/internal/api/client/lists"
+	"github.com/superseriousbusiness/gotosocial/internal/api/client/markers"
 	"github.com/superseriousbusiness/gotosocial/internal/api/client/media"
 	"github.com/superseriousbusiness/gotosocial/internal/api/client/notifications"
 	"github.com/superseriousbusiness/gotosocial/internal/api/client/preferences"
@@ -64,6 +65,7 @@ type Client struct {
 	followRequests *followrequests.Module // api/v1/follow_requests
 	instance       *instance.Module       // api/v1/instance
 	lists          *lists.Module          // api/v1/lists
+	markers        *markers.Module        // api/v1/markers
 	media          *media.Module          // api/v1/media, api/v2/media
 	notifications  *notifications.Module  // api/v1/notifications
 	preferences    *preferences.Module    // api/v1/preferences
@@ -104,6 +106,7 @@ func (c *Client) Route(r router.Router, m ...gin.HandlerFunc) {
 	c.followRequests.Route(h)
 	c.instance.Route(h)
 	c.lists.Route(h)
+	c.markers.Route(h)
 	c.media.Route(h)
 	c.notifications.Route(h)
 	c.preferences.Route(h)
@@ -132,6 +135,7 @@ func NewClient(db db.DB, p *processing.Processor) *Client {
 		followRequests: followrequests.New(p),
 		instance:       instance.New(p),
 		lists:          lists.New(p),
+		markers:        markers.New(p),
 		media:          media.New(p),
 		notifications:  notifications.New(p),
 		preferences:    preferences.New(p),
diff --git a/internal/api/client/markers/markers.go b/internal/api/client/markers/markers.go
new file mode 100644
index 000000000..fcf584d12
--- /dev/null
+++ b/internal/api/client/markers/markers.go
@@ -0,0 +1,45 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package markers
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	"github.com/superseriousbusiness/gotosocial/internal/processing"
+)
+
+const (
+	// BasePath is the base path for serving the markers API, minus the 'api' prefix
+	BasePath = "/v1/markers"
+)
+
+type Module struct {
+	processor *processing.Processor
+}
+
+func New(processor *processing.Processor) *Module {
+	return &Module{
+		processor: processor,
+	}
+}
+
+func (m *Module) Route(attachHandler func(method string, path string, f ...gin.HandlerFunc) gin.IRoutes) {
+	attachHandler(http.MethodGet, BasePath, m.MarkersGETHandler)
+	attachHandler(http.MethodPost, BasePath, m.MarkersPOSTHandler)
+}
diff --git a/internal/api/client/markers/markersget.go b/internal/api/client/markers/markersget.go
new file mode 100644
index 000000000..eb403dcc6
--- /dev/null
+++ b/internal/api/client/markers/markersget.go
@@ -0,0 +1,108 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package markers
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	apiutil "github.com/superseriousbusiness/gotosocial/internal/api/util"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/oauth"
+	"github.com/superseriousbusiness/gotosocial/internal/validate"
+)
+
+// MarkersGETHandler swagger:operation GET /api/v1/markers markersGet
+//
+// Get timeline markers by name
+//
+//	---
+//	tags:
+//	- markers
+//
+//	produces:
+//	- application/json
+//
+//	parameters:
+//	-
+//		name: timeline
+//		type: array
+//		items:
+//			type: string
+//			enum:
+//				- home
+//				- notifications
+//		description: Timelines to retrieve.
+//		in: query
+//
+//	security:
+//	- OAuth2 Bearer:
+//		- read:statuses
+//
+//	responses:
+//		'200':
+//			description: Requested markers
+//			schema:
+//				"$ref": "#/definitions/markers"
+//		'400':
+//			description: bad request
+//		'401':
+//			description: unauthorized
+//		'500':
+//			description: internal server error
+func (m *Module) MarkersGETHandler(c *gin.Context) {
+	authed, err := oauth.Authed(c, true, true, true, true)
+	if err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorUnauthorized(err, err.Error()), m.processor.InstanceGetV1)
+		return
+	}
+
+	names, errWithCode := parseMarkerNames(c.QueryArray("timeline[]"))
+	if errWithCode != nil {
+		apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGetV1)
+	}
+
+	marker, errWithCode := m.processor.Markers().Get(c.Request.Context(), authed.Account, names)
+	if errWithCode != nil {
+		apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGetV1)
+		return
+	}
+
+	c.JSON(http.StatusOK, marker)
+}
+
+// parseMarkerNames turns a list of strings into a set of valid marker timeline names, or returns an error.
+func parseMarkerNames(nameStrings []string) ([]apimodel.MarkerName, gtserror.WithCode) {
+	nameSet := make(map[apimodel.MarkerName]struct{}, apimodel.MarkerNameNumValues)
+	for _, timelineString := range nameStrings {
+		if err := validate.MarkerName(timelineString); err != nil {
+			return nil, gtserror.NewErrorBadRequest(err, err.Error())
+		}
+		nameSet[apimodel.MarkerName(timelineString)] = struct{}{}
+	}
+
+	i := 0
+	names := make([]apimodel.MarkerName, len(nameSet))
+	for name := range nameSet {
+		names[i] = name
+		i++
+	}
+
+	return names, nil
+}
diff --git a/internal/api/client/markers/markerspost.go b/internal/api/client/markers/markerspost.go
new file mode 100644
index 000000000..3167becac
--- /dev/null
+++ b/internal/api/client/markers/markerspost.go
@@ -0,0 +1,110 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package markers
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	apiutil "github.com/superseriousbusiness/gotosocial/internal/api/util"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/oauth"
+)
+
+// MarkersPOSTHandler swagger:operation POST /api/v1/markers markersPost
+//
+// Update timeline markers by name
+//
+//	---
+//	tags:
+//	- markers
+//
+//	consumes:
+//	- multipart/form-data
+//
+//	produces:
+//	- application/json
+//
+//	parameters:
+//	-
+//		name: home[last_read_id]
+//		type: string
+//		description: Last status ID read on the home timeline.
+//		in: formData
+//	-
+//		name: notifications[last_read_id]
+//		type: string
+//		description: Last notification ID read on the notifications timeline.
+//		in: formData
+//
+//	security:
+//	- OAuth2 Bearer:
+//		- write:statuses
+//
+//	responses:
+//		'200':
+//			description: Requested markers
+//			schema:
+//				"$ref": "#/definitions/markers"
+//		'400':
+//			description: bad request
+//		'401':
+//			description: unauthorized
+//		'409':
+//			description: conflict (when two clients try to update the same timeline at the same time)
+//		'500':
+//			description: internal server error
+func (m *Module) MarkersPOSTHandler(c *gin.Context) {
+	authed, err := oauth.Authed(c, true, true, true, true)
+	if err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorUnauthorized(err, err.Error()), m.processor.InstanceGetV1)
+		return
+	}
+
+	form := &apimodel.MarkerPostRequest{}
+	if err := c.ShouldBind(form); err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), m.processor.InstanceGetV1)
+		return
+	}
+
+	markers := make([]*gtsmodel.Marker, 0, apimodel.MarkerNameNumValues)
+	if homeLastReadID := form.HomeLastReadID(); homeLastReadID != "" {
+		markers = append(markers, &gtsmodel.Marker{
+			AccountID:  authed.Account.ID,
+			Name:       gtsmodel.MarkerNameHome,
+			LastReadID: homeLastReadID,
+		})
+	}
+	if notificationsLastReadID := form.NotificationsLastReadID(); notificationsLastReadID != "" {
+		markers = append(markers, &gtsmodel.Marker{
+			AccountID:  authed.Account.ID,
+			Name:       gtsmodel.MarkerNameNotifications,
+			LastReadID: notificationsLastReadID,
+		})
+	}
+
+	marker, errWithCode := m.processor.Markers().Update(c.Request.Context(), markers)
+	if errWithCode != nil {
+		apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGetV1)
+		return
+	}
+
+	c.JSON(http.StatusOK, marker)
+}
diff --git a/internal/api/model/marker.go b/internal/api/model/marker.go
index f64b75ab4..f2d5cb296 100644
--- a/internal/api/model/marker.go
+++ b/internal/api/model/marker.go
@@ -20,9 +20,9 @@ package model
 // Marker represents the last read position within a user's timelines.
 type Marker struct {
 	// Information about the user's position in the home timeline.
-	Home *TimelineMarker `json:"home"`
+	Home *TimelineMarker `json:"home,omitempty"`
 	// Information about the user's position in their notifications.
-	Notifications *TimelineMarker `json:"notifications"`
+	Notifications *TimelineMarker `json:"notifications,omitempty"`
 }
 
 // TimelineMarker contains information about a user's progress through a specific timeline.
@@ -32,5 +32,46 @@ type TimelineMarker struct {
 	// The timestamp of when the marker was set (ISO 8601 Datetime)
 	UpdatedAt string `json:"updated_at"`
 	// Used for locking to prevent write conflicts.
-	Version string `json:"version"`
+	Version int `json:"version"`
+}
+
+// MarkerName is the name of one of the timelines we can store markers for.
+type MarkerName string
+
+const (
+	MarkerNameHome          MarkerName = "home"
+	MarkerNameNotifications MarkerName = "notifications"
+	MarkerNameNumValues                = 2
+)
+
+// MarkerPostRequest models a request to update one or more markers.
+// This has two sets of fields to support a goofy nested map structure in both form data and JSON bodies.
+//
+// swagger:ignore
+type MarkerPostRequest struct {
+	Home                        *MarkerPostRequestMarker `json:"home"`
+	FormHomeLastReadID          string                   `form:"home[last_read_id]"`
+	Notifications               *MarkerPostRequestMarker `json:"notifications"`
+	FormNotificationsLastReadID string                   `form:"notifications[last_read_id]"`
+}
+
+type MarkerPostRequestMarker struct {
+	// The ID of the most recently viewed entity.
+	LastReadID string `json:"last_read_id"`
+}
+
+// HomeLastReadID should be used instead of Home or FormHomeLastReadID.
+func (r *MarkerPostRequest) HomeLastReadID() string {
+	if r.Home != nil {
+		return r.Home.LastReadID
+	}
+	return r.FormHomeLastReadID
+}
+
+// NotificationsLastReadID should be used instead of Notifications or FormNotificationsLastReadID.
+func (r *MarkerPostRequest) NotificationsLastReadID() string {
+	if r.Notifications != nil {
+		return r.Notifications.LastReadID
+	}
+	return r.FormNotificationsLastReadID
 }