add update checks

includes cache of latest version and page to view if updates are
available with a link to the latest update's release notes and a link to
check for the latest update now, refreshing the cache manually.

admin.go

@@ -13,16 +13,17 @@ package writefreely
 import (
 	"database/sql"
 	"fmt"
+	"net/http"
+	"runtime"
+	"strconv"
+	"time"
+
 	"github.com/gogits/gogs/pkg/tool"
 	"github.com/gorilla/mux"
 	"github.com/writeas/impart"
 	"github.com/writeas/web-core/auth"
 	"github.com/writeas/web-core/log"
 	"github.com/writeas/writefreely/config"
-	"net/http"
-	"runtime"
-	"strconv"
-	"time"
 )
 
 var (
@@ -112,7 +113,6 @@ func handleViewAdminDash(app *App, u *User, w http.ResponseWriter, r *http.Reque
 		Message:       r.FormValue("m"),
 		ConfigMessage: r.FormValue("cm"),
 	}
-
 	showUserPage(w, "admin", p)
 	return nil
 }
@@ -451,3 +451,30 @@ func adminResetPassword(app *App, u *User, newPass string) error {
 	}
 	return nil
 }
+
+func handleViewAdminUpdates(app *App, u *User, w http.ResponseWriter, r *http.Request) error {
+	check := r.URL.Query().Get("check")
+
+	if check == "now" && app.cfg.App.UpdateChecks {
+		app.updates.CheckNow()
+	}
+
+	p := struct {
+		*UserPage
+		LastChecked      string
+		LatestVersion    string
+		LatestReleaseURL string
+		UpdateAvailable  bool
+	}{
+		UserPage: NewUserPage(app, r, u, "Updates", nil),
+	}
+	if app.cfg.App.UpdateChecks {
+		p.LastChecked = app.updates.lastCheck.Format("January 2, 2006, 3:04 PM")
+		p.LatestVersion = app.updates.LatestVersion()
+		p.LatestReleaseURL = app.updates.ReleaseURL()
+		p.UpdateAvailable = app.updates.AreAvailable()
+	}
+
+	showUserPage(w, "app-updates", p)
+	return nil
+}

app.go

@@ -30,7 +30,7 @@ import (
 	"github.com/gorilla/schema"
 	"github.com/gorilla/sessions"
 	"github.com/manifoldco/promptui"
-	"github.com/writeas/go-strip-markdown"
+	stripmd "github.com/writeas/go-strip-markdown"
 	"github.com/writeas/impart"
 	"github.com/writeas/web-core/auth"
 	"github.com/writeas/web-core/converter"
@@ -72,6 +72,7 @@ type App struct {
 	keys         *key.Keychain
 	sessionStore *sessions.CookieStore
 	formDecoder  *schema.Decoder
+	updates      *updatesCache
 
 	timeline *localTimeline
 }
@@ -346,6 +347,8 @@ func Initialize(apper Apper, debug bool) (*App, error) {
 	if err != nil {
 		return nil, fmt.Errorf("init keys: %s", err)
 	}
+	apper.App().InitUpdates()
+
 	apper.App().InitSession()
 
 	apper.App().InitDecoder()

config.ini.example

@@ -23,4 +23,5 @@ max_blogs         = 1
 federation        = true
 public_stats      = true
 private           = false
+update_checks     = true
 

config/config.go

@@ -12,8 +12,9 @@
 package config
 
 import (
-	"gopkg.in/ini.v1"
 	"strings"
+
+	"gopkg.in/ini.v1"
 )
 
 const (
@@ -89,6 +90,9 @@ type (
 
 		// Defaults
 		DefaultVisibility string `ini:"default_visibility"`
+
+		// Check for Updates
+		UpdateChecks bool `ini:"update_checks"`
 	}
 
 	// Config holds the complete configuration for running a writefreely instance

go.mod

@@ -67,7 +67,7 @@ require (
 	golang.org/x/lint v0.0.0-20181217174547-8f45f776aaf1 // indirect
 	golang.org/x/net v0.0.0-20190206173232-65e2d4e15006 // indirect
 	golang.org/x/sys v0.0.0-20190209173611-3b5209105503 // indirect
-	golang.org/x/tools v0.0.0-20190208222737-3744606dbb67 // indirect
+	golang.org/x/tools v0.0.0-20190208222737-3744606dbb67
 	google.golang.org/appengine v1.4.0 // indirect
 	gopkg.in/alecthomas/kingpin.v3-unstable v3.0.0-20180810215634-df19058c872c // indirect
 	gopkg.in/bufio.v1 v1.0.0-20140618132640-567b2bfa514e // indirect

routes.go

@@ -11,13 +11,14 @@
 package writefreely
 
 import (
+	"net/http"
+	"path/filepath"
+	"strings"
+
 	"github.com/gorilla/mux"
 	"github.com/writeas/go-webfinger"
 	"github.com/writeas/web-core/log"
 	"github.com/writefreely/go-nodeinfo"
-	"net/http"
-	"path/filepath"
-	"strings"
 )
 
 // InitStaticRoutes adds routes for serving static files.
@@ -147,6 +148,7 @@ func InitRoutes(apper Apper, r *mux.Router) *mux.Router {
 	write.HandleFunc("/admin/page/{slug}", handler.Admin(handleViewAdminPage)).Methods("GET")
 	write.HandleFunc("/admin/update/config", handler.AdminApper(handleAdminUpdateConfig)).Methods("POST")
 	write.HandleFunc("/admin/update/{page}", handler.Admin(handleAdminUpdateSite)).Methods("POST")
+	write.HandleFunc("/admin/updates", handler.Admin(handleViewAdminUpdates)).Methods("GET")
 
 	// Handle special pages first
 	write.HandleFunc("/login", handler.Web(viewLogin, UserLevelNoneRequired))

semver.go

@@ -0,0 +1,315 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package semver implements comparison of semantic version strings.
+// In this package, semantic version strings must begin with a leading "v",
+// as in "v1.0.0".
+//
+// The general form of a semantic version string accepted by this package is
+//
+//	vMAJOR[.MINOR[.PATCH[-PRERELEASE][+BUILD]]]
+//
+// where square brackets indicate optional parts of the syntax;
+// MAJOR, MINOR, and PATCH are decimal integers without extra leading zeros;
+// PRERELEASE and BUILD are each a series of non-empty dot-separated identifiers
+// using only alphanumeric characters and hyphens; and
+// all-numeric PRERELEASE identifiers must not have leading zeros.
+//
+// This package follows Semantic Versioning 2.0.0 (see semver.org)
+// with two exceptions. First, it requires the "v" prefix. Second, it recognizes
+// vMAJOR and vMAJOR.MINOR (with no prerelease or build suffixes)
+// as shorthands for vMAJOR.0.0 and vMAJOR.MINOR.0.
+
+// Package writefreely
+// copied from
+// https://github.com/golang/tools/blob/master/internal/semver/semver.go
+// slight modifications made
+package writefreely
+
+// parsed returns the parsed form of a semantic version string.
+type parsed struct {
+	major      string
+	minor      string
+	patch      string
+	short      string
+	prerelease string
+	build      string
+	err        string
+}
+
+// IsValid reports whether v is a valid semantic version string.
+func IsValid(v string) bool {
+	_, ok := semParse(v)
+	return ok
+}
+
+// CompareSemver returns an integer comparing two versions according to
+// according to semantic version precedence.
+// The result will be 0 if v == w, -1 if v < w, or +1 if v > w.
+//
+// An invalid semantic version string is considered less than a valid one.
+// All invalid semantic version strings compare equal to each other.
+func CompareSemver(v, w string) int {
+	pv, ok1 := semParse(v)
+	pw, ok2 := semParse(w)
+	if !ok1 && !ok2 {
+		return 0
+	}
+	if !ok1 {
+		return -1
+	}
+	if !ok2 {
+		return +1
+	}
+	if c := compareInt(pv.major, pw.major); c != 0 {
+		return c
+	}
+	if c := compareInt(pv.minor, pw.minor); c != 0 {
+		return c
+	}
+	if c := compareInt(pv.patch, pw.patch); c != 0 {
+		return c
+	}
+	return comparePrerelease(pv.prerelease, pw.prerelease)
+}
+
+func semParse(v string) (p parsed, ok bool) {
+	if v == "" || v[0] != 'v' {
+		p.err = "missing v prefix"
+		return
+	}
+	p.major, v, ok = parseInt(v[1:])
+	if !ok {
+		p.err = "bad major version"
+		return
+	}
+	if v == "" {
+		p.minor = "0"
+		p.patch = "0"
+		p.short = ".0.0"
+		return
+	}
+	if v[0] != '.' {
+		p.err = "bad minor prefix"
+		ok = false
+		return
+	}
+	p.minor, v, ok = parseInt(v[1:])
+	if !ok {
+		p.err = "bad minor version"
+		return
+	}
+	if v == "" {
+		p.patch = "0"
+		p.short = ".0"
+		return
+	}
+	if v[0] != '.' {
+		p.err = "bad patch prefix"
+		ok = false
+		return
+	}
+	p.patch, v, ok = parseInt(v[1:])
+	if !ok {
+		p.err = "bad patch version"
+		return
+	}
+	if len(v) > 0 && v[0] == '-' {
+		p.prerelease, v, ok = parsePrerelease(v)
+		if !ok {
+			p.err = "bad prerelease"
+			return
+		}
+	}
+	if len(v) > 0 && v[0] == '+' {
+		p.build, v, ok = parseBuild(v)
+		if !ok {
+			p.err = "bad build"
+			return
+		}
+	}
+	if v != "" {
+		p.err = "junk on end"
+		ok = false
+		return
+	}
+	ok = true
+	return
+}
+
+func parseInt(v string) (t, rest string, ok bool) {
+	if v == "" {
+		return
+	}
+	if v[0] < '0' || '9' < v[0] {
+		return
+	}
+	i := 1
+	for i < len(v) && '0' <= v[i] && v[i] <= '9' {
+		i++
+	}
+	if v[0] == '0' && i != 1 {
+		return
+	}
+	return v[:i], v[i:], true
+}
+
+func parsePrerelease(v string) (t, rest string, ok bool) {
+	// "A pre-release version MAY be denoted by appending a hyphen and
+	// a series of dot separated identifiers immediately following the patch version.
+	// Identifiers MUST comprise only ASCII alphanumerics and hyphen [0-9A-Za-z-].
+	// Identifiers MUST NOT be empty. Numeric identifiers MUST NOT include leading zeroes."
+	if v == "" || v[0] != '-' {
+		return
+	}
+	i := 1
+	start := 1
+	for i < len(v) && v[i] != '+' {
+		if !isIdentChar(v[i]) && v[i] != '.' {
+			return
+		}
+		if v[i] == '.' {
+			if start == i || isBadNum(v[start:i]) {
+				return
+			}
+			start = i + 1
+		}
+		i++
+	}
+	if start == i || isBadNum(v[start:i]) {
+		return
+	}
+	return v[:i], v[i:], true
+}
+
+func parseBuild(v string) (t, rest string, ok bool) {
+	if v == "" || v[0] != '+' {
+		return
+	}
+	i := 1
+	start := 1
+	for i < len(v) {
+		if !isIdentChar(v[i]) {
+			return
+		}
+		if v[i] == '.' {
+			if start == i {
+				return
+			}
+			start = i + 1
+		}
+		i++
+	}
+	if start == i {
+		return
+	}
+	return v[:i], v[i:], true
+}
+
+func isIdentChar(c byte) bool {
+	return 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z' || '0' <= c && c <= '9' || c == '-'
+}
+
+func isBadNum(v string) bool {
+	i := 0
+	for i < len(v) && '0' <= v[i] && v[i] <= '9' {
+		i++
+	}
+	return i == len(v) && i > 1 && v[0] == '0'
+}
+
+func isNum(v string) bool {
+	i := 0
+	for i < len(v) && '0' <= v[i] && v[i] <= '9' {
+		i++
+	}
+	return i == len(v)
+}
+
+func compareInt(x, y string) int {
+	if x == y {
+		return 0
+	}
+	if len(x) < len(y) {
+		return -1
+	}
+	if len(x) > len(y) {
+		return +1
+	}
+	if x < y {
+		return -1
+	} else {
+		return +1
+	}
+}
+
+func comparePrerelease(x, y string) int {
+	// "When major, minor, and patch are equal, a pre-release version has
+	// lower precedence than a normal version.
+	// Example: 1.0.0-alpha < 1.0.0.
+	// Precedence for two pre-release versions with the same major, minor,
+	// and patch version MUST be determined by comparing each dot separated
+	// identifier from left to right until a difference is found as follows:
+	// identifiers consisting of only digits are compared numerically and
+	// identifiers with letters or hyphens are compared lexically in ASCII
+	// sort order. Numeric identifiers always have lower precedence than
+	// non-numeric identifiers. A larger set of pre-release fields has a
+	// higher precedence than a smaller set, if all of the preceding
+	// identifiers are equal.
+	// Example: 1.0.0-alpha < 1.0.0-alpha.1 < 1.0.0-alpha.beta <
+	// 1.0.0-beta < 1.0.0-beta.2 < 1.0.0-beta.11 < 1.0.0-rc.1 < 1.0.0."
+	if x == y {
+		return 0
+	}
+	if x == "" {
+		return +1
+	}
+	if y == "" {
+		return -1
+	}
+	for x != "" && y != "" {
+		x = x[1:] // skip - or .
+		y = y[1:] // skip - or .
+		var dx, dy string
+		dx, x = nextIdent(x)
+		dy, y = nextIdent(y)
+		if dx != dy {
+			ix := isNum(dx)
+			iy := isNum(dy)
+			if ix != iy {
+				if ix {
+					return -1
+				} else {
+					return +1
+				}
+			}
+			if ix {
+				if len(dx) < len(dy) {
+					return -1
+				}
+				if len(dx) > len(dy) {
+					return +1
+				}
+			}
+			if dx < dy {
+				return -1
+			} else {
+				return +1
+			}
+		}
+	}
+	if x == "" {
+		return -1
+	} else {
+		return +1
+	}
+}
+
+func nextIdent(x string) (dx, rest string) {
+	i := 0
+	for i < len(x) && x[i] != '.' {
+		i++
+	}
+	return x[:i], x[i:]
+}

templates/user/admin/app-updates.tmpl

@@ -0,0 +1,23 @@
+{{define "app-updates"}}
+{{template "header" .}}
+
+<style type="text/css">
+</style>
+
+<div class="content-container snug">
+	{{template "admin-header" .}}
+
+	{{if not .UpdateAvailable}}
+  <p class="alert info">WriteFreely is up to date.</p>
+  {{else}}
+  <p class="alert info">WriteFreely {{.LatestVersion}} is available.</p>
+  <section class="changelog">
+    For details on features, bug fixes or notes on upgrading, <a href="{{.LatestReleaseURL}}">read the release notes</a>.
+  </section>
+  {{end}}
+  <p>Last checked at: {{.LastChecked}}. <a href="/admin/updates?check=now">Check now</a>.</p>
+
+{{template "footer" .}}
+
+{{template "body-end" .}}
+{{end}}

templates/user/include/header.tmpl

@@ -69,6 +69,7 @@
 		{{if not .SingleUser}}
 		<a href="/admin/users" {{if eq .Path "/admin/users"}}class="selected"{{end}}>Users</a>
 		<a href="/admin/pages" {{if eq .Path "/admin/pages"}}class="selected"{{end}}>Pages</a>
+		{{if .UpdateChecks}}<a href="/admin/updates" {{if eq .Path "/admin/updates"}}class="selected"{{end}}>Updates</a>{{end}}
 		{{end}}
 	</nav>
 </header>

updates.go

@@ -0,0 +1,103 @@
+/*
+ * Copyright © 2018-2019 A Bunch Tell LLC.
+ *
+ * This file is part of WriteFreely.
+ *
+ * WriteFreely is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, included
+ * in the LICENSE file in this source code package.
+ */
+
+package writefreely
+
+import (
+	"io/ioutil"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+)
+
+// updatesCacheTime is the default interval between cache updates for new
+// software versions
+const updatesCacheTime = 12 * time.Hour
+
+// updatesCache holds data about current and new releases of the writefreely
+// software
+type updatesCache struct {
+	mu             sync.Mutex
+	frequency      time.Duration
+	lastCheck      time.Time
+	latestVersion  string
+	currentVersion string
+}
+
+// CheckNow asks for the latest released version of writefreely and updates
+// the cache last checked time. If the version postdates the current 'latest'
+// the version value is replaced.
+func (uc *updatesCache) CheckNow() error {
+	uc.mu.Lock()
+	defer uc.mu.Unlock()
+	latestRemote, err := newVersionCheck(uc.currentVersion)
+	if err != nil {
+		return err
+	}
+	uc.lastCheck = time.Now()
+	if CompareSemver(latestRemote, uc.latestVersion) == 1 {
+		uc.latestVersion = latestRemote
+	}
+	return nil
+}
+
+// AreAvailable updates the cache if the frequency duration has passed
+// then returns if the latest release is newer than the current running version.
+func (uc updatesCache) AreAvailable() bool {
+	if time.Since(uc.lastCheck) > uc.frequency {
+		uc.CheckNow()
+	}
+	return CompareSemver(uc.latestVersion, uc.currentVersion) == 1
+}
+
+// LatestVersion returns the latest stored version available.
+func (uc updatesCache) LatestVersion() string {
+	return uc.latestVersion
+}
+
+// ReleaseURL returns the full URL to the blog.writefreely.org release notes
+// for the latest version as stored in the cache.
+func (uc updatesCache) ReleaseURL() string {
+	ver := strings.TrimPrefix(uc.latestVersion, "v")
+	ver = strings.TrimSuffix(ver, ".0")
+	return "https://blog.writefreely.org/version-" + strings.ReplaceAll(ver, ".", "-")
+}
+
+// newUpdatesCache returns an initialized updates cache
+func newUpdatesCache() *updatesCache {
+	cache := updatesCache{
+		frequency:      updatesCacheTime,
+		currentVersion: "v" + softwareVer,
+	}
+	cache.CheckNow()
+	return &cache
+}
+
+// InitUpdates initializes the updates cache, if the config value is set
+func (app *App) InitUpdates() {
+	if app.cfg.App.UpdateChecks {
+		app.updates = newUpdatesCache()
+	}
+}
+
+func newVersionCheck(serverVersion string) (string, error) {
+	res, err := http.Get("https://version.writefreely.org")
+	if err == nil && res.StatusCode == http.StatusOK {
+		defer res.Body.Close()
+
+		body, err := ioutil.ReadAll(res.Body)
+		if err != nil {
+			return "", err
+		}
+		return string(body), nil
+	}
+	return "", err
+}