From 57b6027431452ffce40725043a9a82a63ca5670a Mon Sep 17 00:00:00 2001
From: Lloyd McKenzie <lmckenzie@gevityinc.com>
Date: Wed, 20 Nov 2019 23:27:01 +0100
Subject: [PATCH] Enable packages containing instructions to append files

---
 .../java/org/hl7/fhir/utilities/TextFile.java    | 12 ++++++++++--
 .../org/hl7/fhir/utilities/cache/NpmPackage.java | 16 ++++++++++++++++
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/TextFile.java b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/TextFile.java
index 05091e8fa..6a3fa47bd 100644
--- a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/TextFile.java
+++ b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/TextFile.java
@@ -61,6 +61,9 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -194,8 +197,13 @@ public class TextFile {
     OutputStream sw = new FileOutputStream(file);
     sw.write(bytes);
     sw.flush();
-    sw.close();
-    
+    sw.close(); 
+  }
+  
+  public static void appendBytesToFile(byte[] bytes, String path) throws IOException {
+    byte[] linebreak = new byte[] {13, 10};
+    Files.write(Paths.get(path), linebreak, StandardOpenOption.APPEND);
+    Files.write(Paths.get(path), bytes, StandardOpenOption.APPEND);
   }
 
   public static byte[] fileToBytes(String srcFile) throws FileNotFoundException, IOException {
diff --git a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/cache/NpmPackage.java b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/cache/NpmPackage.java
index 128414c34..fcbd3847f 100644
--- a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/cache/NpmPackage.java
+++ b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/cache/NpmPackage.java
@@ -498,10 +498,26 @@ public class NpmPackage {
   }
 
   public void unPack(String dir) throws IOException {
+    unPack (dir, false);
+  }
+
+  public void unPackWithAppend(String dir) throws IOException {
+    unPack (dir, true);
+  }
+
+  public void unPack(String dir, boolean withAppend) throws IOException {
     for (String s : content.keySet()) {
       String fn = Utilities.path(dir, s);
       String dn = Utilities.getDirectoryForFile(fn);
       Utilities.createDirectory(dn);
+      File f = new File(s);
+      if (withAppend && f.getName().startsWith("_append.")) {
+        String appendFn = Utilities.path(dir, Utilities.getDirectoryForFile(s), f.getName().substring(8));
+        if (new File(appendFn).exists())
+          TextFile.appendBytesToFile(content.get(s), appendFn);        
+        else
+          TextFile.bytesToFile(content.get(s), appendFn);        
+      } else
       TextFile.bytesToFile(content.get(s), fn);
     }
     if (path != null)