Merge pull request #319 from IBM/Readme-Changes

move transform exceptions doc out of ray runtime to overview

data-processing-lib/doc/overview.md

@@ -42,6 +42,7 @@ the `DataAccess` instance (see below) according to the CLI parameters.
 To learn more consider the following:
 
 * [Transforms](transforms.md)
+* [Transform Exceptions](transform-exceptions.md)
 * [Transform Runtimes](transform-runtimes.md)
 * [Transform Examples](transform-tutorial-examples.md)
 * [Testing Transforms](transform-testing.md)

data-processing-lib/doc/ray-runtime.md

@@ -124,22 +124,6 @@ The `computed_execution_stats()` provides an opportunity to augment the statisti
 collected and aggregated by the TransformStatistics actor. It is called by the RayOrchestrator
 after all files have been processed.
 
-## Exceptions
-A transform may find that it needs to signal error conditions.
-For example, if a referenced model could not be loaded or
-a given input data (e.g., pyarrow Table) does not have the expected format (.e.g, columns).
-In general, it should identify such conditions by raising an exception. 
-With this in mind, there are two types of exceptions:
-
-1. Those that would not allow any data to be processed (e.g. model loading problem).
-2. Those that would not allow a specific datum to be processed (e.g. missing column).
-
-In the first situation the transform should throw an exception from the initializer, which
-will cause the Ray framework to terminate processing of all data. 
-In the second situation (identified in the `transform()` or `flush()` methods), the transform
-should throw an exception from the associated method.
-This will cause only the error-causing datume to be ignored and not written out,
-but allow continued processing of tables by the transform.
-In both cases, the framework will log the exception as an error.
+
 
 

data-processing-lib/doc/transform-exceptions.md

@@ -0,0 +1,17 @@
+# Exceptions
+A transform may find that it needs to signal error conditions.
+For example, if a referenced model could not be loaded or
+a given input data (e.g., pyarrow Table) does not have the expected format (.e.g, columns).
+In general, it should identify such conditions by raising an exception. 
+With this in mind, there are two types of exceptions:
+
+1. Those that would not allow any data to be processed (e.g. model loading problem).
+2. Those that would not allow a specific datum to be processed (e.g. missing column).
+
+In the first situation the transform should throw an exception from the initializer, which
+will cause the runtime to terminate processing of all data. 
+In the second situation (identified in the `transform()` or `flush()` methods), the transform
+should throw an exception from the associated method.
+This will cause only the error-causing datum to be ignored and not written out,
+but allow continued processing of tables by the transform.
+In both cases, the runtime will log the exception as an error.