add ktx syntax for storage metadata

Author: Bas Buijsen

firebase-storage/src/androidMain/kotlin/dev/gitlive/firebase/storage/storage.kt

@@ -126,7 +126,7 @@ fun FirebaseStorageMetadata.toStorageMetadata(): StorageMetadata {
         .setContentLanguage(this.contentLanguage)
         .setContentType(this.contentType)
         .apply {
-            customMetadata?.entries?.forEach {
+            customMetadata.entries.forEach {
                 (key, value) -> setCustomMetadata(key, value)
             }
         }.build()

firebase-storage/src/commonMain/kotlin/dev/gitlive/firebase/storage/storage.kt

@@ -64,15 +64,26 @@ interface ProgressFlow : Flow<Progress> {
     fun cancel()
 }
 
-
 expect class FirebaseStorageException : FirebaseException
 
 data class FirebaseStorageMetadata(
-    val md5Hash: String? = null,
-    val cacheControl: String? = null,
-    val contentDisposition: String? = null,
-    val contentEncoding: String? = null,
-    val contentLanguage: String? = null,
-    val contentType: String? = null,
-    val customMetadata: Map<String, String>? = null
-)
+    var md5Hash: String? = null,
+    var cacheControl: String? = null,
+    var contentDisposition: String? = null,
+    var contentEncoding: String? = null,
+    var contentLanguage: String? = null,
+    var contentType: String? = null,
+    var customMetadata: MutableMap<String, String> = mutableMapOf()
+) {
+    fun setCustomMetadata(key: String, value: String?) {
+        value?.let {
+            customMetadata[key] = it
+        }
+    }
+}
+
+fun storageMetadata(init: FirebaseStorageMetadata.() -> Unit): FirebaseStorageMetadata {
+    val metadata = FirebaseStorageMetadata()
+    metadata.init()
+    return metadata
+}

firebase-storage/src/iosMain/kotlin/dev/gitlive/firebase/storage/storage.kt

@@ -151,9 +151,9 @@ suspend inline fun <T, reified R> T.awaitResult(function: T.(callback: (R?, NSEr
 
 fun FirebaseStorageMetadata.toFIRMetadata(): FIRStorageMetadata {
     val metadata = FIRStorageMetadata()
-    val mappedMetadata: Map<Any?, String>? = this.customMetadata?.map {
+    val mappedMetadata: Map<Any?, String> = this.customMetadata.map {
         it.key to it.value
-    }?.toMap()
+    }.toMap()
     metadata.setCustomMetadata(mappedMetadata)
     metadata.setCacheControl(this.cacheControl)
     metadata.setContentDisposition(this.contentDisposition)