Fixes #198.

changes.md

@@ -1,3 +1,7 @@
+#### 0.7.4
+
+- Allow functions in leaf position of a workflow. [#198](https://github.com/onyx-platform/onyx/issues/198)
+
 #### 0.7.3
 
 - Bug fix: Kill-job no longer throws a malformed exception with bad parameters.

doc/user-guide/functions.md

@@ -15,6 +15,7 @@ This section outlines how Onyx programs execute behavior. Onyx uses plain Clojur
   - [Continue Policy](#continue-policy)
   - [Kill Policy](#kill-policy)
 - [Bulk Functions](#bulk-functions)
+- [Leaf Functions](#leaf-functions)
 
 <!-- END doctoc generated TOC please keep comment here to allow auto update -->
 
@@ -138,3 +139,16 @@ And an example catalog function to correspond to this entry:
 ```
 
 The default value for this option is `false`.
+
+#### Leaf Functions
+
+Sometimes you're going to want a node in your workflow with no outgoing connections that doesn't perform I/O against a database. You can do this by setting `:onyx/type` to `:output`, `:onyx/medium` to `:function`, and `:onyx/plugin` to `onyx.peer.function/function`. Then you can specify an `:onyx/fn` pointing to a regular Clojure function. For example:
+
+```clojure
+{:onyx/name :leaf-task
+ :onyx/fn ::add-to-results
+ :onyx/plugin :onyx.peer.function/function
+ :onyx/medium :function
+ :onyx/type :output
+ :onyx/batch-size 20}
+```

test/onyx/peer/leaf_function_test.clj

@@ -50,8 +50,7 @@
     :onyx/medium :function
     :onyx/type :output
     :onyx/batch-size batch-size
-    :onyx/max-peers 1
-    :onyx/doc "Writes segments to a core.async channel"}])
+    :onyx/max-peers 1}])
 
 (def workflow [[:in :inc] [:inc :out]])