refactor postgres connection string building (#27723) (#27869)

Backport #27723 by @mpldr

This patchset changes the connection string builder to use net.URL and
the host/port parser to use the stdlib function for splitting host from
port. It also adds a footnote about a potentially required portnumber
for postgres UNIX sockets.

Fixes: #24552

Co-authored-by: Moritz Poldrack <33086936+mpldr@users.noreply.github.com>

docs/content/administration/config-cheat-sheet.en-us.md

@@ -423,7 +423,7 @@ The following configuration set `Content-Type: application/vnd.android.package-a
 ## Database (`database`)
 
 - `DB_TYPE`: **mysql**: The database type in use \[mysql, postgres, mssql, sqlite3\].
-- `HOST`: **127.0.0.1:3306**: Database host address and port or absolute path for unix socket \[mysql, postgres\] (ex: /var/run/mysqld/mysqld.sock).
+- `HOST`: **127.0.0.1:3306**: Database host address and port or absolute path for unix socket \[mysql, postgres[^1]\] (ex: /var/run/mysqld/mysqld.sock).
 - `NAME`: **gitea**: Database name.
 - `USER`: **root**: Database username.
 - `PASSWD`: **_empty_**: Database user password. Use \`your password\` or """your password""" for quoting if you use special characters in the password.
@@ -454,6 +454,8 @@ The following configuration set `Content-Type: application/vnd.android.package-a
 - `CONN_MAX_LIFETIME` **0 or 3s**: Sets the maximum amount of time a DB connection may be reused - default is 0, meaning there is no limit (except on MySQL where it is 3s - see #6804 & #7071).
 - `AUTO_MIGRATION` **true**: Whether execute database models migrations automatically.
 
+[^1]: It may be necessary to specify a hostport even when listening on a unix socket, as the port is part of the socket name. see [#24552](https://github.com/go-gitea/gitea/issues/24552#issuecomment-1681649367) for additional details.
+
 Please see #8540 & #8273 for further discussion of the appropriate values for `MAX_OPEN_CONNS`, `MAX_IDLE_CONNS` & `CONN_MAX_LIFETIME` and their
 relation to port exhaustion.
 

docs/content/usage/actions/act-runner.en-us.md

@@ -268,6 +268,40 @@ The runner will fetch jobs from the Gitea instance and run them automatically.
 
 Since act runner is still in development, it is recommended to check the latest version and upgrade it regularly.
 
+## Systemd service
+
+It is also possible to run act-runner as a [systemd](https://en.wikipedia.org/wiki/Systemd) service. Create an unprivileged `act_runner` user on your system, and the following file in `/etc/systemd/system/act_runner.service`. The paths in `ExecStart` and `WorkingDirectory` may need to be adjusted depending on where you installed the `act_runner` binary, its configuration file, and the home directory of the `act_runner` user.
+
+```ini
+[Unit]
+Description=Gitea Actions runner
+Documentation=https://gitea.com/gitea/act_runner
+After=docker.service
+
+[Service]
+ExecStart=/usr/local/bin/act_runner daemon --config /etc/act_runner/config.yaml
+ExecReload=/bin/kill -s HUP $MAINPID
+WorkingDirectory=/var/lib/act_runner
+TimeoutSec=0
+RestartSec=10
+Restart=always
+User=act_runner
+
+[Install]
+WantedBy=multi-user.target
+```
+
+Then:
+
+```bash
+# load the new systemd unit file
+sudo systemctl daemon-reload
+# start the service and enable it at boot
+sudo systemctl enable act_runner --now
+```
+
+If using Docker, the `act_runner` user should also be added to the `docker` group before starting the service. Keep in mind that this effectively gives `act_runner` root access to the system [[1]](https://docs.docker.com/engine/security/#docker-daemon-attack-surface).
+
 ## Configuration variable
 
 You can create configuration variables on the user, organization and repository level.

modules/setting/database.go

@@ -6,6 +6,7 @@ package setting
 import (
 	"errors"
 	"fmt"
+	"net"
 	"net/url"
 	"os"
 	"path"
@@ -135,15 +136,18 @@ func DBConnStr() (string, error) {
 // parsePostgreSQLHostPort parses given input in various forms defined in
 // https://www.postgresql.org/docs/current/static/libpq-connect.html#LIBPQ-CONNSTRING
 // and returns proper host and port number.
-func parsePostgreSQLHostPort(info string) (string, string) {
-	host, port := "127.0.0.1", "5432"
-	if strings.Contains(info, ":") && !strings.HasSuffix(info, "]") {
-		idx := strings.LastIndex(info, ":")
-		host = info[:idx]
-		port = info[idx+1:]
-	} else if len(info) > 0 {
+func parsePostgreSQLHostPort(info string) (host, port string) {
+	if h, p, err := net.SplitHostPort(info); err == nil {
+		host, port = h, p
+	} else {
+		// treat the "info" as "host", if it's an IPv6 address, remove the wrapper
 		host = info
+		if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
+			host = host[1 : len(host)-1]
 		}
+	}
+
+	// set fallback values
 	if host == "" {
 		host = "127.0.0.1"
 	}
@@ -155,14 +159,22 @@ func parsePostgreSQLHostPort(info string) (string, string) {
 
 func getPostgreSQLConnectionString(dbHost, dbUser, dbPasswd, dbName, dbParam, dbsslMode string) (connStr string) {
 	host, port := parsePostgreSQLHostPort(dbHost)
-	if host[0] == '/' { // looks like a unix socket
-		connStr = fmt.Sprintf("postgres://%s:%s@:%s/%s%ssslmode=%s&host=%s",
-			url.PathEscape(dbUser), url.PathEscape(dbPasswd), port, dbName, dbParam, dbsslMode, host)
-	} else {
-		connStr = fmt.Sprintf("postgres://%s:%s@%s:%s/%s%ssslmode=%s",
-			url.PathEscape(dbUser), url.PathEscape(dbPasswd), host, port, dbName, dbParam, dbsslMode)
+	connURL := url.URL{
+		Scheme:   "postgres",
+		User:     url.UserPassword(dbUser, dbPasswd),
+		Host:     net.JoinHostPort(host, port),
+		Path:     dbName,
+		OmitHost: false,
+		RawQuery: dbParam,
 	}
-	return connStr
+	query := connURL.Query()
+	if dbHost[0] == '/' { // looks like a unix socket
+		query.Add("host", dbHost)
+		connURL.Host = ":" + port
+	}
+	query.Set("sslmode", dbsslMode)
+	connURL.RawQuery = query.Encode()
+	return connURL.String()
 }
 
 // ParseMSSQLHostPort splits the host into host and port

modules/setting/database_test.go

@@ -10,46 +10,49 @@ import (
 )
 
 func Test_parsePostgreSQLHostPort(t *testing.T) {
-	tests := []struct {
+	tests := map[string]struct {
 		HostPort string
 		Host     string
 		Port     string
 	}{
-		{
+		"host-port": {
 			HostPort: "127.0.0.1:1234",
 			Host:     "127.0.0.1",
 			Port:     "1234",
 		},
-		{
+		"no-port": {
 			HostPort: "127.0.0.1",
 			Host:     "127.0.0.1",
 			Port:     "5432",
 		},
-		{
+		"ipv6-port": {
 			HostPort: "[::1]:1234",
-			Host:     "[::1]",
+			Host:     "::1",
 			Port:     "1234",
 		},
-		{
+		"ipv6-no-port": {
 			HostPort: "[::1]",
-			Host:     "[::1]",
+			Host:     "::1",
 			Port:     "5432",
 		},
-		{
+		"unix-socket": {
 			HostPort: "/tmp/pg.sock:1234",
 			Host:     "/tmp/pg.sock",
 			Port:     "1234",
 		},
-		{
+		"unix-socket-no-port": {
 			HostPort: "/tmp/pg.sock",
 			Host:     "/tmp/pg.sock",
 			Port:     "5432",
 		},
 	}
-	for _, test := range tests {
+	for k, test := range tests {
+		t.Run(k, func(t *testing.T) {
+			t.Log(test.HostPort)
 			host, port := parsePostgreSQLHostPort(test.HostPort)
 			assert.Equal(t, test.Host, host)
 			assert.Equal(t, test.Port, port)
+		})
 	}
 }
 
@@ -72,7 +75,7 @@ func Test_getPostgreSQLConnectionString(t *testing.T) {
 			Name:    "gitea",
 			Param:   "",
 			SSLMode: "false",
-			Output:  "postgres://testuser:space%20space%20%21%23$%25%5E%5E%25%5E%60%60%60-=%3F=@:5432/giteasslmode=false&host=/tmp/pg.sock",
+			Output:  "postgres://testuser:space%20space%20%21%23$%25%5E%5E%25%5E%60%60%60-=%3F=@:5432/gitea?host=%2Ftmp%2Fpg.sock&sslmode=false",
 		},
 		{
 			Host:    "localhost",
@@ -82,7 +85,7 @@ func Test_getPostgreSQLConnectionString(t *testing.T) {
 			Name:    "gitea",
 			Param:   "",
 			SSLMode: "true",
-			Output:  "postgres://pgsqlusername:I%20love%20Gitea%21@localhost:5432/giteasslmode=true",
+			Output:  "postgres://pgsqlusername:I%20love%20Gitea%21@localhost:5432/gitea?sslmode=true",
 		},
 	}
 

web_src/js/markup/math.js

@@ -15,18 +15,28 @@ export async function renderMath() {
     import(/* webpackChunkName: "katex" */'katex/dist/katex.css'),
   ]);
 
+  const MAX_CHARS = 1000;
+  const MAX_SIZE = 25;
+  const MAX_EXPAND = 1000;
+
   for (const el of els) {
     const target = targetElement(el);
     if (target.hasAttribute('data-render-done')) continue;
     const source = el.textContent;
+
+    if (source.length > MAX_CHARS) {
+      displayError(target, new Error(`Math source of ${source.length} characters exceeds the maximum allowed length of ${MAX_CHARS}.`));
+      continue;
+    }
+
     const displayMode = el.classList.contains('display');
     const nodeName = displayMode ? 'p' : 'span';
 
     try {
       const tempEl = document.createElement(nodeName);
       katex.render(source, tempEl, {
-        maxSize: 25,
-        maxExpand: 50,
+        maxSize: MAX_SIZE,
+        maxExpand: MAX_EXPAND,
         displayMode,
       });
       target.replaceWith(tempEl);