From cc85f0520caf5ab5759cca94f40de9f763231c81 Mon Sep 17 00:00:00 2001
From: Alex Osborne <aosborne@nla.gov.au>
Date: Tue, 20 May 2025 15:52:02 +0900
Subject: [PATCH] Add RecordingInputStream.asOutputStream()

Using RecordingInputStream requires an awkward workaround when the API being recorded is not in the form of an InputStream, for example, if it's asynchronous. This adds a method to access the underlying RecordingOutputStream so you can write to it directly when that would be easier.
---
 CHANGES.md                                          |  4 ++++
 .../java/org/archive/io/RecordingInputStream.java   | 13 +++++++++++--
 .../org/archive/io/RecordingInputStreamTest.java    | 13 ++++++++++++-
 3 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/CHANGES.md b/CHANGES.md
index 19c26b2f..6d9c5880 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,6 +1,10 @@
 2.0.0
 -----
 
+### New features
+
+- Added `RecordingInputStream.asOutputStream()` for direct writing of recorded data without an input stream. [#108](https://github.com/iipc/webarchive-commons/pull/108)
+
 ### Removals
 
 #### Removed Apache HttpClient 3.1
diff --git a/src/main/java/org/archive/io/RecordingInputStream.java b/src/main/java/org/archive/io/RecordingInputStream.java
index 95419280..3c9db61f 100644
--- a/src/main/java/org/archive/io/RecordingInputStream.java
+++ b/src/main/java/org/archive/io/RecordingInputStream.java
@@ -383,12 +383,12 @@ public synchronized void mark(int readlimit) {
 
     @Override
     public boolean markSupported() {
-        return this.in.markSupported(); 
+        return in != null && this.in.markSupported();
     }
 
     @Override
     public synchronized void reset() throws IOException {
-        this.in.reset();
+        if (in != null) this.in.reset();
         this.recordingOutputStream.reset();
     }
 
@@ -418,4 +418,13 @@ public void chopAtMessageBodyBegin() {
     public void clearForReuse() throws IOException {
         recordingOutputStream.clearForReuse();
     }
+
+    /**
+     * Returns an OutputStream that can be used for recording input data. This is useful if the input comes in some
+     * form other than an InputStream. For example, if the input is provided by a callback periodically called with
+     * a chunk of data.
+     */
+    public RecordingOutputStream asOutputStream() {
+        return this.recordingOutputStream;
+    }
 }
diff --git a/src/test/java/org/archive/io/RecordingInputStreamTest.java b/src/test/java/org/archive/io/RecordingInputStreamTest.java
index 9ddc7457..49160aa3 100644
--- a/src/test/java/org/archive/io/RecordingInputStreamTest.java
+++ b/src/test/java/org/archive/io/RecordingInputStreamTest.java
@@ -41,7 +41,6 @@ public class RecordingInputStreamTest {
     @TempDir
     File tempDir;
 
-
     /**
      * Test readFullyOrUntil soft (no exception) and hard (exception) 
      * length cutoffs, timeout, and rate-throttling. 
@@ -128,4 +127,16 @@ public void run() {
         }.start();
         
     }
+
+    @Test
+    public void testAsOutputStream() throws IOException {
+        RecordingInputStream ris = new RecordingInputStream(16384, (new File(
+                tempDir, "testAsOutputStream").getAbsolutePath()));
+        ris.open(null);
+        ris.asOutputStream().write("hello".getBytes());
+        ris.close();
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        ris.getReplayInputStream().readFullyTo(baos);
+        assertEquals("hello", baos.toString());
+    }
 }