Update docs, fix some errors

Storage/src/commonMain/kotlin/io/github/jan/supabase/storage/BucketApi.kt

@@ -323,6 +323,11 @@ sealed interface BucketApi {
          */
         const val UPSERT_HEADER = "x-upsert"
 
+        /**
+         * The header to use for the user metadata
+         */
+        const val METADATA_HEADER = "x-metadata"
+
     }
 
 }

Storage/src/commonMain/kotlin/io/github/jan/supabase/storage/BucketApiImpl.kt

@@ -29,6 +29,8 @@ import kotlinx.serialization.json.jsonPrimitive
 import kotlinx.serialization.json.put
 import kotlinx.serialization.json.putJsonArray
 import kotlinx.serialization.json.putJsonObject
+import kotlin.io.encoding.Base64
+import kotlin.io.encoding.ExperimentalEncodingApi
 import kotlin.time.Duration
 
 internal class BucketApiImpl(override val bucketId: String, val storage: StorageImpl, resumableCache: ResumableCache) : BucketApi {
@@ -265,6 +267,7 @@ internal class BucketApiImpl(override val bucketId: String, val storage: Storage
         return FileUploadResponse(id, path, key)
     }
 
+    @OptIn(ExperimentalEncodingApi::class)
     private fun HttpRequestBuilder.defaultUploadRequest(
         path: String,
         data: UploadData,
@@ -277,6 +280,9 @@ internal class BucketApiImpl(override val bucketId: String, val storage: Storage
         })
         header(HttpHeaders.ContentType, optionBuilder.contentType ?: ContentType.defaultForFilePath(path))
         header(UPSERT_HEADER, optionBuilder.upsert.toString())
+        optionBuilder.userMetadata?.let {
+            header(BucketApi.METADATA_HEADER, Base64.encode(it.toString().encodeToByteArray()))
+        }
     }
 
     override suspend fun changePublicStatusTo(public: Boolean) = storage.updateBucket(bucketId) {

Storage/src/commonMain/kotlin/io/github/jan/supabase/storage/FileObject.kt

@@ -59,18 +59,18 @@ data class FileObjectV2(
     @SerialName("updated_at")
     val updatedAt: Instant? = null,
     @SerialName("created_at")
-    val createdAt: Instant?,
+    val createdAt: Instant,
     @SerialName("last_accessed_at")
     val lastAccessedAt: Instant? = null,
-    val metadata: JsonObject?,
+    val metadata: JsonObject? = null,
     val size: Long,
     @SerialName("content_type")
     val rawContentType: String,
-    val etag: String?,
+    val etag: String? = null,
     @SerialName("last_modified")
-    val lastModified: Instant?,
+    val lastModified: Instant? = null,
     @SerialName("cache_control")
-    val cacheControl: String?,
+    val cacheControl: String? = null,
     @Transient @PublishedApi internal val serializer: SupabaseSerializer = KotlinXSerializer()
 ) {
 

Storage/src/commonMain/kotlin/io/github/jan/supabase/storage/UploadOptionBuilder.kt

@@ -13,6 +13,7 @@ import kotlinx.serialization.json.jsonObject
  * Builder for uploading files with additional options
  * @param serializer The serializer to use for encoding the metadata
  * @param upsert Whether to update the file if it already exists
+ * @param userMetadata The user metadata to upload with the file
  * @param contentType The content type of the file. If null, the content type will be inferred from the file extension
  */
 class UploadOptionBuilder(
@@ -24,7 +25,8 @@ class UploadOptionBuilder(
 ) {
 
     /**
-     * Overrides the HTTP request
+     * Adds an [HttpRequestOverride] to the upload request
+     * @param override The override to add
      */
     fun httpOverride(override: HttpRequestOverride) {
         httpRequestOverrides.add(override)