feat: allow fonts to be remote resources

Feature changes:
- publication resources used in font declarations (in CSS documents,
  in inline CSS content of XHTML documents or SVG, or in SVG's
  deprecated `font-face-uri` element) MAY be remote resources.
- remote resource check is dependent on content parsing, so the check is
  moved to *after* the resource contents are checked, and only
  run when checking an entire publication.

Fix:
- check that the item property "remote-resource" is properly set when
  required on items representing CSS documents

Internal changes:
- Add a new `FONT` type to XRefChecker references
- Register as `XRefChecker` references of type `FONT` the paths found in
  CSS `@font-face` declaration and SVG `font-face-uri` elements.
- Add a new `getTypes(path)` public method in `XRefChecker`, to get the
  type(s) of reference(s) to a given publication resource
- Add a new `isRemote(String path)` util method to `PathUtil`
- `CSSHandler` constructor only receives a `ValidationContext`
- add tests

Fix #871, Fix #672

src/main/java/com/adobe/epubcheck/css/CSSChecker.java

@@ -97,8 +97,7 @@ public void runChecks()
  return;
  }
 
- CSSHandler handler = new CSSHandler(path, context.xrefChecker.orNull(), report,
- context.version);
+ CSSHandler handler = new CSSHandler(context);
  if (this.mode == Mode.STRING && this.line > -1)
  {
  handler.setStartingLineNumber(this.line);

src/main/java/com/adobe/epubcheck/css/CSSHandler.java

@@ -1,6 +1,8 @@
 package com.adobe.epubcheck.css;
 
+import java.util.EnumSet;
 import java.util.List;
+import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -19,14 +21,21 @@
 import com.adobe.epubcheck.messages.MessageId;
 import com.adobe.epubcheck.opf.OPFChecker;
 import com.adobe.epubcheck.opf.OPFChecker30;
+import com.adobe.epubcheck.opf.ValidationContext;
 import com.adobe.epubcheck.opf.XRefChecker;
+import com.adobe.epubcheck.opf.XRefChecker.Type;
 import com.adobe.epubcheck.util.EPUBVersion;
 import com.adobe.epubcheck.util.FeatureEnum;
 import com.adobe.epubcheck.util.PathUtil;
+import com.adobe.epubcheck.vocab.PackageVocabs;
+import com.adobe.epubcheck.vocab.PackageVocabs.ITEM_PROPERTIES;
+import com.adobe.epubcheck.vocab.Property;
 import com.google.common.base.CharMatcher;
+import com.google.common.collect.Sets;
 
 public class CSSHandler implements CssContentHandler, CssErrorHandler
 {
+ final ValidationContext context;
  final String path;
  final XRefChecker xrefChecker;
  final Report report;
@@ -44,14 +53,17 @@ public class CSSHandler implements CssContentHandler, CssErrorHandler
  boolean hasFontFaceDeclarations = false;
  boolean inKeyFrames = false;
  CssAtRule atRule = null;
+
+ // properties the must be declared on the related OPF item
+ final Set<ITEM_PROPERTIES> detectedProperties = EnumSet.noneOf(ITEM_PROPERTIES.class);
 
- public CSSHandler(String path, XRefChecker xrefChecker, Report report,
- EPUBVersion version)
+ public CSSHandler(ValidationContext context)
  {
- this.path = path;
- this.xrefChecker = xrefChecker;
- this.report = report;
- this.version = version;
+ this.context = context;
+ this.path = context.path;
+ this.xrefChecker = context.xrefChecker.orNull();
+ this.report = context.report;
+ this.version = context.version;
  }
 
  private EPUBLocation getCorrectedEPUBLocation(String fileName, int lineNumber, int columnNumber, String context)
@@ -104,6 +116,7 @@ public void startDocument()
  @Override
  public void endDocument()
  {
+ checkProperties();
  }
 
  static final Pattern keyframesPattern = Pattern.compile("@((keyframes)|(-moz-keyframes)|(-webkit-keyframes)|(-o-keyframes))");
@@ -135,7 +148,7 @@ else if (uriOrString.getType() == CssConstruct.Type.STRING)
  }
  if (uri != null)
  {
- resolveAndRegister(uri, line, col, atRule.toCssString());
+ resolveAndRegister(uri, line, col, atRule.toCssString(), Type.GENERIC);
  }
  }
  }
@@ -255,7 +268,7 @@ else if (propertyName.equals("src"))
  {
  fontUri = ((CssURI) construct).toUriString();
  fontUri = PathUtil.resolveRelativeReference(path, fontUri);
- //check font mimetypes
+ // check font mimetypes
  String fontMimeType = xrefChecker.getMimeType(fontUri);
  if (fontMimeType != null)
  {
@@ -298,17 +311,20 @@ private void registerURIs(List<CssConstruct> constructs, int line, int col)
  {
  if (construct.getType() == CssConstruct.Type.URI)
  {
- resolveAndRegister(((CssURI) construct).toUriString(), line, col, construct.toCssString());
+ resolveAndRegister(((CssURI) construct).toUriString(), line, col, construct.toCssString(), inFontFace?Type.FONT:Type.GENERIC);
  }
  }
  }
 
- private void resolveAndRegister(String relativeRef, int line, int col, String context)
+ private void resolveAndRegister(String uri, int line, int col, String context, Type type)
  {
- if (relativeRef != null && relativeRef.trim().length() > 0)
+ if (uri != null && uri.trim().length() > 0)
  {
- String resolved = PathUtil.resolveRelativeReference(path, relativeRef);
- xrefChecker.registerReference(path, line + startingLineNumber, col, resolved, XRefChecker.Type.GENERIC);
+ String resolved = PathUtil.resolveRelativeReference(path, uri);
+ xrefChecker.registerReference(path, correctedLineNumber(line), correctedColumnNumber(line, col), resolved, type);
+ if (PathUtil.isRemote(resolved)) {
+ detectedProperties.add(ITEM_PROPERTIES.REMOTE_RESOURCES);
+ }
  }
  else
  {
@@ -339,6 +355,33 @@ private void handleFontFaceInfo()
  }
  }
  }
+
+ protected void checkProperties() {
+
+ // Exit early if we don't have container-level info (single file validation)
+ if (!context.ocf.isPresent()) // single file validation
+ {
+ return;
+ }
+
+ Set<ITEM_PROPERTIES> declaredProperties = Property.filter(context.properties, ITEM_PROPERTIES.class);
+
+ // Check that all properties found in the doc are declared on the OPF item
+ for (ITEM_PROPERTIES property : Sets.difference(detectedProperties, declaredProperties))
+ {
+ report.message(MessageId.OPF_014, EPUBLocation.create(path, startingLineNumber, startingLineNumber),
+ PackageVocabs.ITEM_VOCAB.getName(property));
+ }
+
+ // Check that properties declared in the OPF item were found in the content 
+ Set<ITEM_PROPERTIES> uncheckedProperties = Sets.difference(declaredProperties, detectedProperties)
+ .copyInto(EnumSet.noneOf(ITEM_PROPERTIES.class));
+ if (uncheckedProperties.contains(ITEM_PROPERTIES.REMOTE_RESOURCES))
+ {
+ uncheckedProperties.remove(ITEM_PROPERTIES.REMOTE_RESOURCES);
+ report.message(MessageId.OPF_018, EPUBLocation.create(path, startingLineNumber, startingLineNumber));
+ }
+ }
 
  public void setStartingLineNumber(int offset)
  {

src/main/java/com/adobe/epubcheck/opf/OPFChecker.java

@@ -150,20 +150,29 @@ public void runChecks()
  checkGuide();
  checkBindings();
 
+ // Check items content (publication resources)
  for (OPFItem item : items)
  {
  if (!item.getPath().matches("^[^:/?#]+://.*"))
  {
  checkItemContent(item);
  }
  }
+
+ // Checks items after the content-validation pass
+ // This allows to run checks depending on info collected in publication resources
+ for (OPFItem item : items) {
+ checkItemAfterResourceValidation(item);
+ }
 
  xrefChecker.checkReferences();
  }
+
+ protected void checkItemAfterResourceValidation(OPFItem item) {
+ }
 
  protected void checkBindings()
  {
-
  }
 
  protected void checkGuide()

src/main/java/com/adobe/epubcheck/opf/OPFChecker30.java

@@ -24,6 +24,7 @@
 
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Set;
@@ -38,6 +39,7 @@
 import com.adobe.epubcheck.messages.MessageId;
 import com.adobe.epubcheck.opf.MetadataSet.Metadata;
 import com.adobe.epubcheck.opf.ResourceCollection.Roles;
+import com.adobe.epubcheck.opf.XRefChecker.Type;
 import com.adobe.epubcheck.ops.OPSCheckerFactory;
 import com.adobe.epubcheck.overlay.OverlayCheckerFactory;
 import com.adobe.epubcheck.util.EPUBVersion;
@@ -133,7 +135,25 @@ protected void checkItem(OPFItem item, OPFHandler opfHandler)
 
  // Note: item fallback existence is checked in schematron, i.e.:
  // opfHandler.getItemById(item.getFallback().get()).isPresent() == true
-
+ }
+
+ @Override
+ protected void checkItemAfterResourceValidation(OPFItem item)
+ {
+ XRefChecker xrefChecker = context.xrefChecker.get();
+
+ // Report remote resources when not allowed
+ String mediatype = item.getMimeType();
+ if (item.getPath().matches("^[^:/?#]+://.*") 
+ && !(isAudioType(mediatype)
+ || isVideoType(mediatype)
+ || "application/x-shockwave-flash".equals(mediatype)
+ || isFontType(mediatype)
+ || xrefChecker.getTypes(item.getPath()).equals(EnumSet.of(Type.FONT))))
+ {
+ report.message(MessageId.RSC_006,
+ EPUBLocation.create(path, item.getLineNumber(), item.getColumnNumber()), item.getPath());
+ }
  }
 
  @Override
@@ -488,6 +508,13 @@ public static boolean isCommonVideoType(String type)
  return "video/h264".equals(type) || "video/webm".equals(type)
  || "video/mp4".equals(type);
  }
+
+ public static boolean isFontType(String type)
+ {
+ return type.startsWith("font/")
+ || type.startsWith("application/font-")
+ || type.equals("application/vnd.ms-opentype");
+ }
 
  public static boolean isBlessedFontType(String type)
  {

src/main/java/com/adobe/epubcheck/opf/OPFHandler.java

@@ -303,16 +303,6 @@ else if (name.equals("item"))
  String fallbackStyle = (context.version == EPUBVersion.VERSION_3) ? e
  .getAttribute("fallback") : e.getAttribute("fallback-style");
 
- if (context.version == EPUBVersion.VERSION_3 && href.matches("^[^:/?#]+://.*")
- && !OPFChecker30.isAudioType(mimeType)
- && !OPFChecker30.isVideoType(mimeType)
- && !"application/x-shockwave-flash".equals(mimeType))
- {
- report
- .message(MessageId.RSC_006,
- EPUBLocation.create(path, parser.getLineNumber(), parser.getColumnNumber()),
- href);
- }
 
  OPFItem.Builder itemBuilder = new OPFItem.Builder(id, href, mimeType,
  parser.getLineNumber(), parser.getColumnNumber()).fallback(fallback).fallbackStyle(
@@ -708,6 +698,5 @@ protected void reportItem(OPFItem item)
  EPUBLocation.create(path, item.getLineNumber(), item.getColumnNumber()));
  }
  }
-
  }
 }

src/main/java/com/adobe/epubcheck/opf/XRefChecker.java

@@ -22,9 +22,11 @@
 
 package com.adobe.epubcheck.opf;
 
+import java.util.EnumSet;
 import java.util.Enumeration;
 import java.util.HashSet;
 import java.util.Hashtable;
+import java.util.LinkedList;
 import java.util.Set;
 import java.util.Vector;
 
@@ -34,16 +36,20 @@
 import com.adobe.epubcheck.ocf.OCFPackage;
 import com.adobe.epubcheck.util.EPUBVersion;
 import com.adobe.epubcheck.util.FeatureEnum;
+import com.adobe.epubcheck.util.PathUtil;
 import com.adobe.epubcheck.vocab.PackageVocabs;
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Sets;
 
 public class XRefChecker
 {
 
  public static enum Type
  {
  GENERIC,
+ FONT,
  HYPERLINK,
  LINK,
  IMAGE,
@@ -153,6 +159,23 @@ public Optional<Boolean> hasValidFallback(String path)
  return resources.get(path) != null ? Optional.of(resources.get(path).hasValidItemFallback)
  : Optional.<Boolean> absent();
  }
+
+ /**
+ * Returns set (possibly multiple) types of refereences to the given resource
+ * @param path the path to a publication resource
+ * @return an immutable {@link EnumSet} containing the types of references to {@code path}. 
+ */
+ public Set<Type> getTypes(String path) {
+ LinkedList<Type> types = new LinkedList<>();
+ for (Reference reference : references)
+ {
+ if (Preconditions.checkNotNull(path).equals(reference.refResource))
+ {
+ types.add(reference.type);
+ }
+ }
+ return Sets.immutableEnumSet(types);
+ }
 
  public Set<String> getBindingsMimeTypes()
  {
@@ -200,7 +223,7 @@ public void registerReference(String srcResource, int srcLineNumber, int srcColu
  // see http://code.google.com/p/epubcheck/issues/detail?id=190
  // see http://code.google.com/p/epubcheck/issues/detail?id=261
  int query = ref.indexOf('?');
- if (query >= 0 && !ref.matches("^[^:/?#]+://.*"))
+ if (query >= 0 && !PathUtil.isRemote(ref))
  {
  ref = ref.substring(0, query).trim();
  }
@@ -245,7 +268,7 @@ private void checkReference(Reference ref)
  {
  if (version == EPUBVersion.VERSION_3 && ref.type == Type.LINK)
  {
- if (ref.refResource.matches("^[^:/?#]+://.*") || ocf.hasEntry(ref.refResource))
+ if (PathUtil.isRemote(ref.refResource) || ocf.hasEntry(ref.refResource))
  {
  return;
  }
@@ -256,13 +279,13 @@ private void checkReference(Reference ref)
  ref.refResource);
  }
  }
- else if (ref.refResource.matches("^[^:/?#]+://.*") && !(version == EPUBVersion.VERSION_3
- && (ref.type == Type.AUDIO || ref.type == Type.VIDEO)))
+ else if (PathUtil.isRemote(ref.refResource) && !(version == EPUBVersion.VERSION_3
+ && (ref.type == Type.AUDIO || ref.type == Type.VIDEO || ref.type == Type.FONT)))
  {
  report.message(MessageId.RSC_006,
  EPUBLocation.create(ref.source, ref.lineNumber, ref.columnNumber, ref.refResource));
  }
- else if (!ocf.hasEntry(ref.refResource) && !ref.refResource.matches("^[^:/?#]+://.*"))
+ else if (!ocf.hasEntry(ref.refResource) && !PathUtil.isRemote(ref.refResource))
  {
  report.message(MessageId.RSC_007,
  EPUBLocation.create(ref.source, ref.lineNumber, ref.columnNumber, ref.refResource),
@@ -382,7 +405,7 @@ else if (ref.fragment.contains("=") && host != null && host.item.getProperties()
  return;
  }
  // Fragment Identifier (by default)
- else
+ else if (!PathUtil.isRemote(ref.refResource))
  {
  Anchor anchor = res.anchors.get(ref.fragment);
  if (anchor == null)

src/main/java/com/adobe/epubcheck/ops/OPSHandler.java

@@ -268,6 +268,19 @@ else if (uri.getScheme() != null)
  }
  processHyperlink(href);
  }
+
+
+
+ protected void checkSVGFontFaceURI(XMLElement e, String attrNS, String attr)
+ {
+ String href = e.getAttributeNS(attrNS, attr);
+ if (xrefChecker.isPresent() && href != null)
+ {
+ href = PathUtil.resolveRelativeReference(base, href);
+ xrefChecker.get().registerReference(path, parser.getLineNumber(), parser.getColumnNumber(),
+ href, XRefChecker.Type.FONT);
+ }
+ }
 
  protected void processHyperlink(String href)
  {
@@ -343,6 +356,10 @@ else if (name.equals("image"))
  {
  checkImage(e, "http://www.w3.org/1999/xlink", "href");
  }
+ else if (name.equals("font-face-uri"))
+ {
+ checkSVGFontFaceURI(e, "http://www.w3.org/1999/xlink", "href");
+ }
  checkPaint(e, "fill");
  checkPaint(e, "stroke");
  }