Docs: Markdown is no longer web app only

Android renders Markdown since 1.17.8 (#310).

.github/workflows/release.yaml

@@ -37,7 +37,7 @@ jobs:
           cache: 'npm'
           cache-dependency-path: './web/package-lock.json'
       - name: Docker login
-        uses: docker/login-action@dbcb813823bdd20940b903addbd779551569679f # v4.6.0
+        uses: docker/login-action@371161bbe7024a29a25c5e19bfcbc0804fe9ad2c # v4.5.2
         with:
           username: ${{ github.repository_owner }}
           password: ${{ secrets.DOCKER_HUB_TOKEN }}

docs/publish.md

@@ -666,7 +666,7 @@ them with a comma, e.g. `tag1,tag2,tag3`.
 _Supported on:_ :material-android: :material-firefox:
 
 You can format messages using [Markdown](https://www.markdownguide.org/basic-syntax/) 🤩. That means you can use 
-**bold text**, *italicized text*, links, images, and more. Supported Markdown features (web app only for now):
+**bold text**, *italicized text*, links, images, and more. Supported Markdown features:
 
 - [Emphasis](https://www.markdownguide.org/basic-syntax/#emphasis) such as **bold** (`**bold**`), *italics* (`*italics*`)
 - [Links](https://www.markdownguide.org/basic-syntax/#links) (`[some tool](https://ntfy.sh)`)

message/cache.go

@@ -300,7 +300,8 @@ func (c *Cache) MarkPublished(m *model.Message) error {
 	return err
 }
 
-// MessagesCount returns the total number of messages in the cache
+// MessagesCount returns the total number of messages in the cache. On Postgres, this is the
+// planner's estimate once the table has been analyzed, not an exact count.
 func (c *Cache) MessagesCount() (int, error) {
 	rows, err := c.db.ReadOnly().Query(c.queries.selectMessagesCount)
 	if err != nil {

message/cache_postgres.go

@@ -62,8 +62,13 @@ const (
 		ORDER BY time, id
 	`
 	postgresUpdateMessagePublishedQuery = `UPDATE message SET published = TRUE WHERE mid = $1`
-	postgresSelectMessagesCountQuery    = `SELECT COUNT(*) FROM message`
+	// Planner estimate, since a COUNT(*) scans the whole table; reltuples is -1 if never analyzed
-	postgresSelectTopicsQuery           = `SELECT topic FROM message GROUP BY topic`
+	postgresSelectMessagesCountQuery = `
+		SELECT CASE WHEN reltuples < 0 THEN (SELECT COUNT(*) FROM message) ELSE reltuples::BIGINT END
+		FROM pg_class
+		WHERE oid = 'message'::regclass
+	`
+	postgresSelectTopicsQuery = `SELECT topic FROM message GROUP BY topic`
 
 	postgresDeleteExpiredMessagesQuery         = `DELETE FROM message WHERE mid IN (SELECT mid FROM message WHERE expires <= $1 AND published = TRUE LIMIT $2)`
 	postgresMarkExpiredAttachmentsDeletedQuery = `UPDATE message SET attachment_deleted = TRUE WHERE mid IN (SELECT mid FROM message WHERE attachment_expires > 0 AND attachment_expires <= $1 AND attachment_deleted = FALSE LIMIT $2)`

message/cache_postgres_test.go

@@ -74,3 +74,28 @@ func TestPostgresStore_Migration_From14(t *testing.T) {
 	require.Nil(t, err)
 	require.Equal(t, dbtest.PostgresSchema(t, freshDB), dbtest.PostgresSchema(t, testDB))
 }
+
+func TestPostgresStore_MessagesCount_UsesPlannerEstimate(t *testing.T) {
+	// The manager calls MessagesCount every minute for a metric; a COUNT(*) scans the whole
+	// table on every call, so once the table has been analyzed, the planner's estimate is used
+	testDB := dbtest.CreateTestPostgres(t)
+	store, err := message.NewPostgresStore(testDB, 0, 0)
+	require.Nil(t, err)
+	for i := 0; i < 10; i++ {
+		require.Nil(t, store.AddMessage(model.NewDefaultMessage("mytopic", "some message")))
+	}
+
+	// Never analyzed: falls back to an exact count
+	count, err := store.MessagesCount()
+	require.Nil(t, err)
+	require.Equal(t, 10, count)
+
+	// Analyzed, then rows deleted: the estimate lags until the next (auto)analyze
+	_, err = testDB.Exec(`ANALYZE message`)
+	require.Nil(t, err)
+	_, err = testDB.Exec(`DELETE FROM message WHERE id IN (SELECT id FROM message LIMIT 4)`)
+	require.Nil(t, err)
+	count, err = store.MessagesCount()
+	require.Nil(t, err)
+	require.Equal(t, 10, count)
+}