Allow escape sequences to span multiple lines and support default fg/bg colors

CHANGELOG.md

@@ -2,6 +2,7 @@
 ============
 
 * Your contribution here.
+* [#137](https://github.com/jenkinsci/ansicolor-plugin/pull/137): Allow escape sequences to span multiple lines and support color maps that set default background/foreground colors - [@dwnusbaum](https://github.com/dwnusbaum).
 
 0.6.1 (01/04/2019)
 ============

src/main/java/hudson/plugins/ansicolor/AnsiAttributeElement.java

@@ -1,5 +1,7 @@
 package hudson.plugins.ansicolor;
 
+import java.io.Serializable;
+
 /**
  * Represents an HTML elements which maps to an ANSI attribute.
  *
@@ -12,7 +14,9 @@
  * other software or testing the HTML may be emitted otherwise.
  */
 
-class AnsiAttributeElement {
+class AnsiAttributeElement implements Serializable {
+    private static final long serialVersionUID = 1L;
+
     public static enum AnsiAttrType {
         DEFAULT, BOLD, ITALIC, UNDERLINE, STRIKEOUT, FRAMED, OVERLINE, FG, BG, FGBG
     }
@@ -65,6 +69,11 @@ public int hashCode() {
         return result;
     }
 
+    @Override
+    public String toString() {
+        return "AnsiAttributeElement{ansiAttrType=" + ansiAttrType + ",name=" + name + ",attributes=" + attributes + "}";
+    }
+
     public static AnsiAttributeElement bold() {
         return new AnsiAttributeElement(AnsiAttributeElement.AnsiAttrType.BOLD, "b", "");
     }

src/main/java/hudson/plugins/ansicolor/AnsiHtmlOutputStream.java

@@ -30,7 +30,10 @@
 import java.io.IOException;
 import java.io.OutputStream;
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
 import java.util.Stack;
+import javax.annotation.Nonnull;
 
 /**
  * Filters an outputstream of ANSI escape sequences and emits appropriate HTML elements instead.
@@ -59,16 +62,27 @@ private static enum State {
     private boolean swapColors = false;  // true if negative / inverse mode is active (esc[7m)
 
     // A Deque might be a better choice, but we are constrained by the Java 5 API.
-    private ArrayList<AnsiAttributeElement> openTags = new ArrayList<AnsiAttributeElement>();
+    private ArrayList<AnsiAttributeElement> openTags;
 
     private OutputStream logOutput;
 
-    public AnsiHtmlOutputStream(final OutputStream os, final AnsiColorMap colorMap,
-        final AnsiAttributeElement.Emitter emitter) {
+    /**
+     * @param tagsToOpen A list of tags to open in the given order immediately after opening the tag for the default
+     * foreground/background colors (if such colors are specified by the color map) before any data is written to the
+     * underlying stream.
+     */
+    /*package*/ AnsiHtmlOutputStream(final OutputStream os, final AnsiColorMap colorMap,
+        final AnsiAttributeElement.Emitter emitter, @Nonnull List<AnsiAttributeElement> tagsToOpen) {
         super(os);
         this.logOutput = os;
         this.colorMap = colorMap;
         this.emitter = emitter;
+        this.openTags = new ArrayList<>(tagsToOpen);
+    }
+
+    public AnsiHtmlOutputStream(final OutputStream os, final AnsiColorMap colorMap,
+        final AnsiAttributeElement.Emitter emitter) {
+        this(os, colorMap, emitter, Collections.emptyList());
     }
 
     // Debug output for plugin developers. Puts the debug message into the html page
@@ -93,6 +107,13 @@ private void stopConcealing() {
         this.out = logOutput;
     }
 
+    /**
+     * @return A copy of the {@link AnsiAttributeElement}s which are currently opened, in order from outermost to innermost tag.
+     */
+    /*package*/ List<AnsiAttributeElement> getOpenTags() {
+        return new ArrayList<>(openTags);
+    }
+
     private void openTag(AnsiAttributeElement tag) throws IOException {
         openTags.add(tag);
         tag.emitOpen(emitter);
@@ -198,6 +219,9 @@ public void write(int data) throws IOException {
         // the preamble is an ANSI escape sequence itself.
 
         if (state == State.INIT) {
+            List<AnsiAttributeElement> tagsToOpen = new ArrayList<>(openTags);
+            openTags.clear();
+
             Integer defaultFg = colorMap.getDefaultForeground();
             Integer defaultBg = colorMap.getDefaultBackground();
 
@@ -207,6 +231,10 @@ public void write(int data) throws IOException {
                         (defaultFg != null ? "color: " + colorMap.getNormal(defaultFg) + ";" : "") + "\""));
             }
 
+            for (AnsiAttributeElement tag : tagsToOpen) {
+                openTag(tag);
+            }
+
             state = State.DATA;
         }
 

src/main/java/hudson/plugins/ansicolor/ColorConsoleAnnotator.java

@@ -31,8 +31,11 @@
 import hudson.model.Queue;
 import hudson.model.Run;
 import java.io.IOException;
+import java.util.Collections;
+import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
+import javax.annotation.Nonnull;
 import jenkins.model.Jenkins;
 import org.apache.commons.io.output.CountingOutputStream;
 import org.apache.commons.io.output.NullOutputStream;
@@ -50,39 +53,60 @@ final class ColorConsoleAnnotator extends ConsoleAnnotator<Object> {
     private static final long serialVersionUID = 1;
 
     private final String colorMapName;
+    private final @Nonnull List<AnsiAttributeElement> openTags;
 
-    ColorConsoleAnnotator(String colorMapName) {
+    ColorConsoleAnnotator(String colorMapName, List<AnsiAttributeElement> openTags) {
         this.colorMapName = colorMapName;
-        LOGGER.fine("creating annotator with colorMapName=" + colorMapName);
+        this.openTags = openTags;
+        LOGGER.log(Level.FINE, "creating annotator with colorMapName={0} openTags={1}", new Object[] { colorMapName, openTags });
+    }
+
+    ColorConsoleAnnotator(String colorMapName) {
+        this(colorMapName, Collections.emptyList());
     }
 
     @Override
     public ConsoleAnnotator<Object> annotate(Object context, MarkupText text) {
         String s = text.getText();
-        if (s.indexOf('\u001B') != -1) {
-            AnsiColorMap colorMap = Jenkins.get().getDescriptorByType(AnsiColorBuildWrapper.DescriptorImpl.class).getColorMap(colorMapName);
+        List<AnsiAttributeElement> nextOpenTags = openTags;
+        AnsiColorMap colorMap = Jenkins.get().getDescriptorByType(AnsiColorBuildWrapper.DescriptorImpl.class).getColorMap(colorMapName);
+        if (s.indexOf('\u001B') != -1 || !openTags.isEmpty() || colorMap.getDefaultBackground() != null || colorMap.getDefaultForeground() != null) {
             CountingOutputStream outgoing = new CountingOutputStream(new NullOutputStream());
             class EmitterImpl implements AnsiAttributeElement.Emitter {
                 CountingOutputStream incoming;
                 int adjustment;
                 int lastPoint = -1; // multiple HTML tags may be emitted for one control sequence
                 @Override
                 public void emitHtml(String html) {
-                    LOGGER.log(Level.FINEST, "emitting {0} @{1}/{2}", new Object[] { html, incoming.getCount(), s.length() });
-                    text.addMarkup(incoming.getCount(), html);
-                    if (incoming.getCount() != lastPoint) {
-                        lastPoint = incoming.getCount();
-                        int hide = incoming.getCount() - outgoing.getCount() - adjustment;
-                        LOGGER.log(Level.FINEST, "hiding {0} @{1}", new Object[] { hide, outgoing.getCount() + adjustment });
-                        text.addMarkup(outgoing.getCount() + adjustment, outgoing.getCount() + adjustment + hide, "<!--", "-->");
-                        adjustment += hide;
+                    int inCount = incoming.getCount();
+                    int outCount = outgoing.getCount() + adjustment;
+                    // All ANSI escapes sequences contain at least 2 bytes on modern platforms, so any HTML emitted
+                    // directly after the first character is received is due to the initialization process of the stream and
+                    // belongs at position 0 (i.e. default background/foreground colors).
+                    if (inCount == 1) {
+                        inCount = 0;
+                    }
+                    LOGGER.log(Level.FINEST, "emitting {0} @{1}/{2}", new Object[] { html, inCount, text.getText().length() });
+                    text.addMarkup(inCount, html);
+                    if (inCount != lastPoint) {
+                        lastPoint = inCount;
+                        int hide = inCount - outCount;
+                        // If openTags is not empty, but there are no escape sequences directly on this line, or if we
+                        // are emitting closing tags when closing the stream, there is nothing to hide.
+                        if (hide != 0) {
+                            LOGGER.log(Level.FINEST, "hiding {0} @{1}", new Object[] { hide, outCount });
+                            text.addMarkup(outCount, outCount + hide, "<!--", "-->");
+                            adjustment += hide;
+                        }
                     }
                 }
             }
             EmitterImpl emitter = new EmitterImpl();
-            CountingOutputStream incoming = new CountingOutputStream(new AnsiHtmlOutputStream(outgoing, colorMap, emitter));
-            emitter.incoming = incoming;
-            try {
+            // We need to reopen tags that were still open at the end of the previous line so the stream's state is
+            // correct in case those tags are closed in the middle of this line.
+            try (AnsiHtmlOutputStream ansiOs = new AnsiHtmlOutputStream(outgoing, colorMap, emitter, openTags);
+                    CountingOutputStream incoming = new CountingOutputStream(ansiOs)) {
+                emitter.incoming = incoming;
                 /*
                  * We only use AnsiHtmlOutputStream for its calls to Emitter.emitHtml when it encounters ANSI escape
                  * sequences; the output of the stream will be discarded. To know where to insert HTML in the MarkupText,
@@ -102,20 +126,30 @@ public void emitHtml(String html) {
                     }
                     incoming.write(c);
                 }
+                nextOpenTags = ansiOs.getOpenTags();
+                if (colorMap.getDefaultBackground() != null || colorMap.getDefaultForeground() != null) {
+                    // The default color scheme will be opened automatically at the beginning of the stream on the next
+                    // line, so we don't want to duplicate it.
+                    // AnsiHtmlOutputStream#getOpenTags makes a copy so calling `remove` is safe.
+                    nextOpenTags.remove(0);
+                }
+                // Tags open at the end of the line are closed when the stream is closed by the try-with-resources block.
             } catch (IOException x) {
                 LOGGER.log(Level.WARNING, null, x);
             }
             LOGGER.finer(() -> "\"" + StringEscapeUtils.escapeJava(s) + "\" → \"" + StringEscapeUtils.escapeJava(text.toString(true)) + "\"");
         }
-        return this;
+        return openTags == nextOpenTags
+                ? this
+                : new ColorConsoleAnnotator(colorMapName, nextOpenTags);
     }
 
     @Extension
     public static final class Factory extends ConsoleAnnotatorFactory<Object> {
 
         @Override
         public ConsoleAnnotator<Object> newInstance(Object context) {
-            LOGGER.fine("context=" + context);
+            LOGGER.log(Level.FINE, "context={0}", context);
             if (context instanceof Run) {
                 ColorizedAction action = ((Run) context).getAction(ColorizedAction.class);
                 if (action != null) {

src/test/java/hudson/plugins/ansicolor/AnsiColorBuildWrapperTest.java

@@ -88,6 +88,61 @@ public boolean perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListen
         });
     }
 
+    @Test
+    public void testMultilineEscapeSequence() throws Exception {
+        story.then(r -> {
+            FreeStyleProject p = r.createFreeStyleProject();
+            p.getBuildWrappersList().add(new AnsiColorBuildWrapper(null));
+            p.getBuildersList().add(new TestBuilder() {
+                @Override
+                public boolean perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListener listener) throws InterruptedException, IOException {
+                    listener.getLogger().println("\u001B[1;34mThis text should be bold and blue");
+                    listener.getLogger().println("Still bold and blue");
+                    listener.getLogger().println("\u001B[mThis text should be normal");
+                    return true;
+                }
+            });
+            FreeStyleBuild b = r.buildAndAssertSuccess(p);
+            StringWriter writer = new StringWriter();
+            b.getLogText().writeHtmlTo(0L, writer);
+            String html = writer.toString();
+            System.out.print(html);
+            assertThat(html.replaceAll("<!--.+?-->", ""),
+                allOf(
+                    containsString("<b><span style=\"color: #1E90FF;\">This text should be bold and blue\n</span></b>"),
+                    containsString("<b><span style=\"color: #1E90FF;\">Still bold and blue\n</span></b>"),
+                    not(containsString("\u001B[m"))));
+        });
+    }
+
+    @Test
+    public void testDefaultForegroundBackground() throws Exception {
+        story.then(r -> {
+            FreeStyleProject p = r.createFreeStyleProject();
+            // The VGA ColorMap sets default foreground and background colors.
+            p.getBuildWrappersList().add(new AnsiColorBuildWrapper("vga"));
+            p.getBuildersList().add(new TestBuilder() {
+                @Override
+                public boolean perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListener listener) throws InterruptedException, IOException {
+                    listener.getLogger().println("White on black");
+                    listener.getLogger().println("\u001B[1;34mBold and blue on black");
+                    listener.getLogger().println("Still bold and blue on black\u001B[mBack to white on black");
+                    return true;
+                }
+            });
+            FreeStyleBuild b = r.buildAndAssertSuccess(p);
+            StringWriter writer = new StringWriter();
+            b.getLogText().writeHtmlTo(0L, writer);
+            String html = writer.toString();
+            System.out.print(html);
+            assertThat(html.replaceAll("<!--.+?-->", ""),
+                allOf(
+                    containsString("<div style=\"background-color: #000000;color: #AAAAAA;\">White on black\n</div>"),
+                    containsString("<div style=\"background-color: #000000;color: #AAAAAA;\"><b><span style=\"color: #0000AA;\">Bold and blue on black\n</span></b></div>"),
+                    containsString("<div style=\"background-color: #000000;color: #AAAAAA;\"><b><span style=\"color: #0000AA;\">Still bold and blue on black</span></b>Back to white on black\n</div>")));
+        });
+    }
+
     @Issue("JENKINS-54133")
     @Test
     public void testWorkflowWrap() throws Exception {