Added ReadableLogRecord and ReadWriteLogRecord interfaces

api/src/OpenTelemetry/Internal/Logging/Types.hs

@@ -4,7 +4,10 @@
 module OpenTelemetry.Internal.Logging.Types (
   LoggerProvider (..),
   Logger (..),
-  LogRecord (..),
+  LogRecord,
+  mkLogRecord,
+  ReadableLogRecord (..),
+  ReadWriteLogRecord (..),
   ImmutableLogRecord (..),
   LogRecordArguments (..),
   emptyLogRecordArguments,
@@ -14,7 +17,7 @@ module OpenTelemetry.Internal.Logging.Types (
 
 import Data.Function (on)
 import qualified Data.HashMap.Strict as H
-import Data.IORef (IORef)
+import Data.IORef (IORef, atomicModifyIORef, modifyIORef, newIORef, readIORef)
 import Data.Int (Int64)
 import Data.Text (Text)
 import OpenTelemetry.Common (Timestamp, TraceFlags)
@@ -47,7 +50,29 @@ data Logger = Logger
 {- | This is a data type that can represent logs from various sources: application log files, machine generated events, system logs, etc. [Specification outlined here.](https://opentelemetry.io/docs/specs/otel/logs/data-model/)
 Existing log formats can be unambiguously mapped to this data type. Reverse mapping from this data type is also possible to the extent that the target log format has equivalent capabilities.
 -}
-data LogRecord a = LogRecord (IORef (ImmutableLogRecord a))
+newtype LogRecord a = LogRecord (IORef (ImmutableLogRecord a))
+
+
+mkLogRecord :: ImmutableLogRecord body -> IO (LogRecord body)
+mkLogRecord = fmap LogRecord . newIORef
+
+
+class ReadableLogRecord r where
+  readLogRecord :: r a -> IO (ImmutableLogRecord a)
+
+
+class (ReadableLogRecord r) => ReadWriteLogRecord r where
+  modifyLogRecord :: r a -> (ImmutableLogRecord a -> ImmutableLogRecord a) -> IO ()
+  atomicModifyLogRecord :: r a -> (ImmutableLogRecord a -> (ImmutableLogRecord a, b)) -> IO b
+
+
+instance ReadableLogRecord LogRecord where
+  readLogRecord (LogRecord ref) = readIORef ref
+
+
+instance ReadWriteLogRecord LogRecord where
+  modifyLogRecord (LogRecord ref) = modifyIORef ref
+  atomicModifyLogRecord (LogRecord ref) = atomicModifyIORef ref
 
 
 data ImmutableLogRecord body = ImmutableLogRecord

api/src/OpenTelemetry/Logging/Core.hs

@@ -16,7 +16,9 @@ module OpenTelemetry.Logging.Core (
   makeLogger,
 
   -- * @LogRecord@ operations
-  LogRecord (..),
+  LogRecord,
+  ReadableLogRecord (..),
+  ReadWriteLogRecord (..),
   LogRecordArguments (..),
   SeverityNumber (..),
   toShortName,
@@ -193,8 +195,7 @@ emitLogRecord
   -> m (LogRecord body)
 emitLogRecord l args = do
   ilr <- createImmutableLogRecord l args
-  lr <- liftIO $ newIORef ilr
-  pure $ LogRecord lr
+  liftIO $ mkLogRecord ilr
 
 
 {- | Add an attribute to a @LogRecord@.
@@ -215,10 +216,10 @@ For example, the 'otel.library.name' attribute is used to record the instrumenta
 
 Any additions to the 'otel.*' namespace MUST be approved as part of OpenTelemetry specification.
 -}
-addAttribute :: (MonadIO m, ToValue a) => LogRecord body -> Text -> a -> m ()
-addAttribute (LogRecord lr) k v =
+addAttribute :: (ReadWriteLogRecord r, MonadIO m, ToValue a) => r body -> Text -> a -> m ()
+addAttribute lr k v =
   liftIO $
-    modifyIORef'
+    modifyLogRecord
       lr
       ( \ilr@ImmutableLogRecord {logRecordAttributes, logRecordLogger} ->
           ilr
@@ -236,10 +237,10 @@ addAttribute (LogRecord lr) k v =
 
  This function may be slightly more performant than repeatedly calling 'addAttribute'.
 -}
-addAttributes :: (MonadIO m, ToValue a) => LogRecord body -> HashMap Text a -> m ()
-addAttributes (LogRecord lr) attrs =
+addAttributes :: (ReadWriteLogRecord r, MonadIO m, ToValue a) => r body -> HashMap Text a -> m ()
+addAttributes lr attrs =
   liftIO $
-    modifyIORef'
+    modifyLogRecord
       lr
       ( \ilr@ImmutableLogRecord {logRecordAttributes, logRecordLogger} ->
           ilr
@@ -256,5 +257,5 @@ addAttributes (LogRecord lr) attrs =
  using it to copy / otherwise use the data to further enrich
  instrumentation.
 -}
-logRecordGetAttributes :: (MonadIO m) => LogRecord a -> m LogAttributes
-logRecordGetAttributes (LogRecord lr) = liftIO $ logRecordAttributes <$> readIORef lr
+logRecordGetAttributes :: (ReadableLogRecord r, MonadIO m) => r a -> m LogAttributes
+logRecordGetAttributes lr = liftIO $ logRecordAttributes <$> readLogRecord lr