Encode images as base64

2 files changed, 29 insertions, 2 deletions

diff --git a/src/main/java/org/zwobble/mammoth/DocumentConverter.java b/src/main/java/org/zwobble/mammoth/DocumentConverter.java
index dce76ad..da10324 100644
--- a/src/main/java/org/zwobble/mammoth/DocumentConverter.java
+++ b/src/main/java/org/zwobble/mammoth/DocumentConverter.java
@@ -1,9 +1,12 @@
 package org.zwobble.mammoth;
 
+import com.google.common.io.ByteStreams;
 import org.zwobble.mammoth.documents.*;
 import org.zwobble.mammoth.html.Html;
 import org.zwobble.mammoth.html.HtmlNode;
 
+import java.io.IOException;
+import java.util.Base64;
 import java.util.List;
 import java.util.Map;
 
@@ -127,7 +130,19 @@ public class DocumentConverter {
 
             @Override
             public List<HtmlNode> visit(Image image) {
-                throw new UnsupportedOperationException();
+                // TODO: handle empty content type
+                return image.getContentType()
+                    .map(contentType -> {
+                        try {
+                            String base64 = Base64.getEncoder().encodeToString(ByteStreams.toByteArray(image.open()));
+                            String src = "data:" + contentType + ";base64," + base64;
+                            return list(Html.selfClosingElement("img", map("src", src)));
+                        } catch (IOException exception) {
+                            // TODO: return a result with a warning
+                            throw new RuntimeException(exception);
+                        }
+                    })
+                    .orElse(list());
             }
         });
     }
diff --git a/src/test/java/org/zwobble/mammoth/tests/DocumentConverterTests.java b/src/test/java/org/zwobble/mammoth/tests/DocumentConverterTests.java
index 1890334..9287f74 100644
--- a/src/test/java/org/zwobble/mammoth/tests/DocumentConverterTests.java
+++ b/src/test/java/org/zwobble/mammoth/tests/DocumentConverterTests.java
@@ -6,7 +6,9 @@ import org.zwobble.mammoth.documents.*;
 import org.zwobble.mammoth.html.Html;
 import org.zwobble.mammoth.html.HtmlNode;
 
+import java.io.ByteArrayInputStream;
 import java.util.List;
+import java.util.Optional;
 
 import static com.natpryce.makeiteasy.MakeItEasy.*;
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -105,7 +107,7 @@ public class DocumentConverterTests {
                 new TableRow(list(
                     new TableCell(list(paragraphWithText("Bottom left"))),
                     new TableCell(list(paragraphWithText("Bottom right")))))))),
-            
+
             deepEquals(list(Html.element("table", list(
                 Html.element("tr", list(
                     Html.element("td", list(Html.element("p", list(Html.text("Top left"))))),
@@ -136,6 +138,16 @@ public class DocumentConverterTests {
             deepEquals(list(Html.element("a", map("id", "doc-42-start")))));
     }
 
+    @Test
+    public void imagesAreConvertedToImageTagsWithDataUriByDefault() {
+        Image image = new Image(
+            Optional.empty(),
+            Optional.of("image/png"),
+            () -> new ByteArrayInputStream(new byte[]{97, 98, 99}));
+        assertThat(
+            convertToHtml(image),
+            deepEquals(list(Html.selfClosingElement("img", map("src", "data:image/png;base64,YWJj")))));
+    }
 
     private List<HtmlNode> convertToHtml(DocumentElement element) {
         return documentConverter().convertToHtml(element);