Add listener support to readme (#96)

Co-authored-by: hfhbd <[email protected]>

Author: hfhbd

README.md

@@ -28,15 +28,37 @@ sqldelight {
 }
 ````
 
+## Usage
+
+```kotlin
+val driver = PostgresNativeDriver(
+    host = "localhost",
+    port = 5432,
+    user = "postgres",
+    database = "postgres",
+    password = "password",
+    options = null,
+    listenerSupport = ListenerSupport.Remote(coroutineScope)
+)
+```
+
+This driver supports local and remote listeners.
+Local listeners only notify this client, ideally for testing or using the database with only one client at a time with
+SQLDelight only.
+Remote listener support uses `NOTIFY` and `LISTEN`, so you can use this with multiple clients or with existing database
+triggers.
+SQLDelight uses and expects the table name as payload, but you can provide a mapper function. 
+
 ## License
 
 Apache 2
 
-This library uses some socket native code from [ktor](https://github.com/ktorio/ktor), licensed under Apache 2. 
+This library uses some socket native code from [ktor](https://github.com/ktorio/ktor), licensed under Apache 2.
 
 ## Contributing
 
 You need libpq installed: https://formulae.brew.sh/formula/libpq#default
+
 You have to add the compiler flags to your path too.
 The exact commands depend on your config, but you will get them during installing libpq with homebrew.
 

postgres-native-sqldelight-driver/src/commonMain/kotlin/app/softwork/sqldelight/postgresdriver/PostgresNativeDriver.kt

@@ -35,10 +35,10 @@ public class PostgresNativeDriver(
 
     private val listeners = mutableMapOf<Query.Listener, Job>()
 
-    private fun CoroutineScope.listen(queryKeysEscaped: List<String>, action: suspend (String) -> Unit) =
+    private fun CoroutineScope.listen(queryKeys: List<String>, action: suspend (String) -> Unit) =
         launch {
             notifications.filter {
-                it in queryKeysEscaped
+                it in queryKeys
             }.collect {
                 action(it)
             }
@@ -367,7 +367,12 @@ private fun CPointer<PGconn>.escaped(value: String): String {
 }
 
 public fun PostgresNativeDriver(
-    host: String, database: String, user: String, password: String, port: Int = 5432, options: String? = null,
+    host: String,
+    database: String,
+    user: String,
+    password: String,
+    port: Int = 5432,
+    options: String? = null,
     listenerSupport: ListenerSupport = ListenerSupport.None
 ): PostgresNativeDriver {
     val conn = PQsetdbLogin(