Merge pull request #3 from brezinajn/master

Fix decodeRecord NPE

Author: jan-tennert

Diff for: Realtime/src/commonMain/kotlin/io/github/jan/supacompose/realtime/events/ChannelAction.kt

@@ -15,35 +15,42 @@ import kotlinx.serialization.json.decodeFromJsonElement
 @Serializable
 data class Column(val name: String, val type: String)
 
-sealed interface ChannelAction {
+interface HasRecord {
 
     /**
-     * Contains data of the row's columns
+     * The new record, if the action has one
      */
-    val columns: List<Column>
+    val record: JsonObject
+}
+
+interface HasOldRecord {
 
     /**
-     * The time when the action was committed
+     * The old record, if the action has one
      */
-    val commitTimestamp: Instant
+    val oldRecord: JsonObject
+}
+
+
+sealed interface ChannelAction {
 
     /**
-     * The old record, if the action has one
+     * Contains data of the row's columns
      */
-    val oldRecord: JsonObject? get() = null
+    val columns: List<Column>
 
     /**
-     * The new record, if the action has one
+     * The time when the action was committed
      */
-    val record: JsonObject? get() = null
+    val commitTimestamp: Instant
 
     @Serializable
     data class Insert(
         override val record: JsonObject,
         override val columns: List<Column>,
         @SerialName("commit_timestamp")
-        override val commitTimestamp: Instant
-    ): ChannelAction
+        override val commitTimestamp: Instant,
+    ) : ChannelAction, HasRecord
 
     @Serializable
     data class Update(
@@ -53,7 +60,7 @@ sealed interface ChannelAction {
         override val columns: List<Column>,
         @SerialName("commit_timestamp")
         override val commitTimestamp: Instant,
-    ): ChannelAction
+    ) : ChannelAction, HasRecord, HasOldRecord
 
     @Serializable
     data class Delete(
@@ -62,30 +69,46 @@ sealed interface ChannelAction {
         override val columns: List<Column>,
         @SerialName("commit_timestamp")
         override val commitTimestamp: Instant,
-    ): ChannelAction
+    ) : ChannelAction, HasOldRecord
 
     @Serializable
     data class Select(
         override val record: JsonObject,
         override val columns: List<Column>,
         @SerialName("commit_timestamp")
         override val commitTimestamp: Instant,
-    ): ChannelAction
+    ) : ChannelAction, HasRecord
 
 }
 
 /**
- * Decodes [ChannelAction.record] as [T] and returns it or null when either [ChannelAction.record] is null or it cannot be decoded as [T]
+ * Decodes [HasRecord.record] as [T] and returns it or returns null when it cannot be decoded as [T]
  */
-inline fun <reified T> ChannelAction.decodeRecordOrNull(json: Json = Json): T? {
+inline fun <reified T> HasRecord.decodeRecordOrNull(json: Json = Json): T? {
     return try {
-        record?.let { json.decodeFromJsonElement<T>(it) }
+        record.let { json.decodeFromJsonElement<T>(it) }
     } catch (e: Exception) {
         null
     }
 }
 
 /**
- * Decodes [ChannelAction.oldRecord] as [T] and returns it
+ * Decodes [HasOldRecord.oldRecord] as [T] and returns it or returns null when it cannot be decoded as [T]
+ */
+inline fun <reified T> HasOldRecord.decodeOldRecordOrNull(json: Json = Json): T? {
+    return try {
+        oldRecord.let { json.decodeFromJsonElement<T>(it) }
+    } catch (e: Exception) {
+        null
+    }
+}
+
+/**
+ * Decodes [HasRecord.record] as [T] and returns it
+ */
+inline fun <reified T> HasRecord.decodeRecord(json: Json = Json) = json.decodeFromJsonElement<T>(record)
+
+/**
+ * Decodes [HasOldRecord.oldRecord] as [T] and returns it
  */
-inline fun <reified T> ChannelAction.decodeRecord(json: Json = Json) = json.decodeFromJsonElement<T>(record!!)
+inline fun <reified T> HasOldRecord.decodeOldRecord(json: Json = Json) = json.decodeFromJsonElement<T>(oldRecord)