Ensure URL fragments to named anchors also validate

build.sbt

@@ -46,7 +46,8 @@ lazy val core = project
     name := "paradox",
     libraryDependencies ++= Library.pegdown,
     libraryDependencies ++= Seq(
-      Library.st4
+      Library.st4,
+      Library.jsoup
     ),
     parallelExecution in Test := false
   )

core/src/main/scala/com/lightbend/paradox/ParadoxProcessor.scala

@@ -20,14 +20,14 @@ import com.lightbend.paradox.template.PageTemplate
 import com.lightbend.paradox.markdown._
 import com.lightbend.paradox.tree.Tree.{ Forest, Location }
 import java.io.{ File, FileOutputStream, OutputStreamWriter }
-import java.net.{ HttpURLConnection, URI }
 import java.nio.charset.StandardCharsets
 
+import org.jsoup.Jsoup
+import org.jsoup.nodes.Document
 import org.pegdown.ast._
 
 import scala.annotation.tailrec
 import scala.collection.JavaConverters._
-import scala.io.Source
 import scala.util.control.NonFatal
 import scala.util.matching.Regex
 
@@ -137,49 +137,65 @@ class ParadoxProcessor(reader: Reader = new Reader, writer: Writer = new Writer)
       validate(Some(root.location))
     }
 
-    def ignore(path: String) = ignorePaths.exists(_.pattern.matcher(path).matches())
-
-    linkCapturer.allLinks.foreach {
-      case CapturedLinkWithSources(CapturedAbsoluteLink(uri), sources) if validateAbsolute && !ignore(uri.toString) =>
-        validateExternalLink(uri, reportErrorOnSources(errorCollector, sources), logger)
-      case CapturedLinkWithSources(CapturedRelativeLink(path, fragment), sources) if !ignore(path) =>
-        fullSite.get(path) match {
-          case Some(file) =>
-            fragment.foreach { f =>
-              validateFragment(path, Source.fromFile(file, "UTF-8").mkString, f, reportErrorOnSources(errorCollector, sources))
-            }
-          case None =>
-            reportErrorOnSources(errorCollector, sources)(s"Could not find path [$path] in site")
-        }
-      case _ =>
-      // Ignore
-    }
+    linkCapturer.allLinks
+      .filterNot(l => ignorePaths.exists(_.pattern.matcher(l.link.toString).matches()))
+      .foreach {
+        case c @ CapturedLink(uri, fragments) if c.isInternal =>
+          fullSite.get(uri.getPath) match {
+            case Some(file) =>
+              if (c.hasFragments) {
+                validateFragments(uri.getPath, Jsoup.parse(file, "UTF-8"), fragments, errorCollector)
+              }
+            case None =>
+              reportErrorOnSources(errorCollector, c.allSources)(s"Could not find path [${uri.getPath}] in site")
+          }
+        case absolute if validateAbsolute =>
+          validateExternalLink(absolute, errorCollector, logger)
+        case _ =>
+        // Ignore
+      }
 
     errorCollector.logErrors(logger)
     errorCollector.errorCount
   }
 
-  private def validateExternalLink(uri: URI, reportError: String => Unit, logger: ParadoxLogger) = {
-    logger.info(s"Validating external link: $uri")
-    val conn = uri.toURL.openConnection().asInstanceOf[HttpURLConnection]
-    conn.addRequestProperty("User-Agent", "Paradox Link Validator <https://github.com/lightbend/paradox>")
+  private def validateExternalLink(capturedLink: CapturedLink, errorContext: ErrorContext, logger: ParadoxLogger) = {
+    logger.info(s"Validating external link: ${capturedLink.link}")
+
+    def reportError = reportErrorOnSources(errorContext, capturedLink.allSources)(_)
+    val url = capturedLink.link.toString
+
     try {
-      if (conn.getResponseCode / 100 == 3) {
-        reportError(s"Received a ${conn.getResponseCode} redirect on external link, location redirected to is [${conn.getHeaderField("Location")}]")
-      } else if (conn.getResponseCode != 200) {
-        reportError(s"Error validating external link, status code was ${conn.getResponseCode}")
+      val response = Jsoup.connect(url)
+        .userAgent("Paradox Link Validator <https://github.com/lightbend/paradox>")
+        .followRedirects(false)
+        .ignoreHttpErrors(true)
+        .ignoreContentType(true)
+        .execute()
+
+      // jsoup doesn't offer any simple way to clean up, the only way to close is to get the body stream and close it,
+      // but if you've already read the response body, that will throw an exception, and there's no way to check if
+      // you've already tried to read the response body, so we can't do that in a finally block, we have to do it
+      // explicitly every time we don't want to consume the stream.
+      def close() = response.bodyStream().close()
+
+      if (response.statusCode() / 100 == 3) {
+        close()
+        reportError(s"Received a ${response.statusCode()} ${response.statusMessage()} on external link, location redirected to is [${response.header("Location")}]")
+      } else if (response.statusCode() != 200) {
+        close()
+        reportError(s"Error validating external link, status was ${response.statusCode()} ${response.statusMessage()}")
       } else {
-        if (uri.getFragment != null) {
-          val content = Source.fromInputStream(conn.getInputStream).mkString
-          validateFragment(uri.toString, content, uri.getFragment, reportError)
+        if (capturedLink.hasFragments) {
+          validateFragments(url, response.parse(), capturedLink.fragments, errorContext)
+        } else {
+          close()
         }
       }
     } catch {
       case NonFatal(e) =>
         reportError(s"Exception occurred when validating external link: $e")
         logger.debug(e)
-    } finally {
-      conn.disconnect()
     }
   }
 
@@ -189,9 +205,13 @@ class ParadoxProcessor(reader: Reader = new Reader, writer: Writer = new Writer)
     }
   }
 
-  private def validateFragment(path: String, content: String, fragment: String, reportError: String => Unit) = {
-    if (!content.contains("id=\"" + fragment + "\"")) {
-      reportError(s"Could not find anchor id [$fragment] in page [$path]")
+  private def validateFragments(path: String, content: Document, fragments: List[CapturedLinkFragment], errorContext: ErrorContext): Unit = {
+    fragments.foreach {
+      case CapturedLinkFragment(Some(fragment), sources) =>
+        if (content.getElementById(fragment) == null && content.select(s"a[name=$fragment]").isEmpty) {
+          reportErrorOnSources(errorContext, sources)(s"Could not find anchor [$fragment] in page [$path]")
+        }
+      case _ =>
     }
   }
 

core/src/main/scala/com/lightbend/paradox/markdown/LinkCapturer.scala

@@ -89,10 +89,10 @@ class LinkCapturer {
     }
   }
 
-  def allLinks: List[CapturedLinkWithSources] = {
+  def allLinks: List[CapturedLink] = {
+    // First, resolve the links, discarding links that we can't resolve.
     links.collect {
-
-      case (page, node, uri) if isPageInSite(page, uri) =>
+      case Link(page, node, uri, fragment) if isPageInSite(page, uri) =>
         val path = node match {
           // Javadoc links may use the frames style, and may reference index.html, if so, need to drop it.
           case d: DirectiveNode if d.name == "javadoc" && uri.getQuery != null =>
@@ -107,19 +107,22 @@ class LinkCapturer {
         val pathWithIndex = if (path.endsWith("/")) uri.getPath + "index.html"
         else path
 
-        val relativePath = URI.create(page.path).resolve(pathWithIndex).getPath
-
-        (CapturedRelativeLink(relativePath, Option(uri.getFragment)), page, node)
-
-      case (page, node, uri) if uri.getAuthority != null =>
-        (CapturedAbsoluteLink(uri), page, node)
-
-    }.groupBy(_._1).map {
-      case (link, links) =>
-        CapturedLinkWithSources(link, links.map {
-          case (_, page, node) => (page.file, node)
-        })
-    }.toList
+        val resolvedUri = URI.create(page.path).resolve(pathWithIndex)
+        Link(page, node, resolvedUri, fragment)
+
+      case link @ Link(_, _, uri, _) if uri.getAuthority != null => link
+    }.groupBy(_.uri)
+      .toList
+      .map {
+        case (uri, links) =>
+          val fragments = links.groupBy(_.fragment)
+            .toList
+            .map {
+              case (fragment, links) =>
+                CapturedLinkFragment(fragment, links.map(l => (l.page.file, l.node)))
+            }
+          CapturedLink(uri, fragments)
+      }
   }
 
   private def isPageInSite(page: Page, uri: URI): Boolean = {
@@ -136,18 +139,29 @@ class LinkCapturer {
   }
 
   private var nodeOverride: Option[Node] = None
-  private var links: List[(Page, Node, URI)] = Nil
+
+  private case class Link(page: Page, node: Node, uri: URI, fragment: Option[String])
+
+  private var links: List[Link] = Nil
 
   def capture(page: Page, node: Node, rendering: LinkRenderer.Rendering): LinkRenderer.Rendering = {
-    links = (page, nodeOverride.getOrElse(node), URI.create(rendering.href)) :: links
+    val fullUri = URI.create(rendering.href)
+    val (uri, fragment) = if (fullUri.getFragment == null) (fullUri, None)
+    else (new URI(fullUri.getScheme, fullUri.getAuthority, fullUri.getPath, fullUri.getQuery, null), Some(fullUri.getFragment))
+    links = Link(page, nodeOverride.getOrElse(node), uri, fragment) :: links
     rendering
   }
 }
 
-case class CapturedLinkWithSources(link: CapturedLink, sources: List[(File, Node)])
-sealed trait CapturedLink
-case class CapturedAbsoluteLink(link: URI) extends CapturedLink
-case class CapturedRelativeLink(path: String, fragment: Option[String]) extends CapturedLink
+case class CapturedLink(link: URI, fragments: List[CapturedLinkFragment]) {
+  def allSources = fragments.flatMap(_.sources)
+
+  def isInternal = link.getAuthority == null && link.getPath != null
+
+  def hasFragments = fragments.size > 1 || fragments.headOption.flatMap(_.fragment).nonEmpty
+}
+
+case class CapturedLinkFragment(fragment: Option[String], sources: List[(File, Node)])
 
 private class LinkCapturerRenderer(capturer: LinkCapturer, renderer: LinkRenderer, page: Page) extends LinkRenderer {
   private def capture(node: Node, rendering: LinkRenderer.Rendering) = capturer.capture(page, node, rendering)

plugin/src/sbt-test/paradox/validation/build.sbt

@@ -1,2 +1,10 @@
 lazy val root = (project in file("."))
     .enablePlugins(ParadoxPlugin)
+
+lazy val additionalInternalMappings = settingKey[List[(File, String)]]("Additional mappings to add to paradox mappings")
+lazy val additionalMappings = settingKey[List[(File, String)]]("Additional mappings to add to paradox mappings")
+
+additionalInternalMappings := Nil
+additionalMappings := Nil
+(Compile / paradox / mappings) ++= additionalInternalMappings.value
+(Compile / paradoxValidateInternalLinks / mappings) ++= additionalMappings.value

plugin/src/sbt-test/paradox/validation/src/main/paradox/index.md

@@ -1,8 +1,12 @@
 [docs site path link](test.html#frag)
+[docs site path link name frag](test.html#namefrag)
 
 [outside docs path link](../outside.html#frag)
 
-https://www.lightbend.com/thispagedoesnotexist
+This URL should 404 (or otherwise fail)
+https://github.com/lightbend/thisrepodoesnotexist
+This URL should 301 (or otherwise fail)
+https://lightbend.com
 
 Including this in build means we depend on github.com being up. Probably ok.
 https://github.com/

plugin/src/sbt-test/paradox/validation/test

@@ -5,12 +5,11 @@
 -> paradoxValidateInternalLinks
 
 # Add the path, but without the fragment, so validation still fails
-> set (Compile / paradox / mappings) += (file("withoutfragment.html") -> ("test.html"))
+> set additionalInternalMappings := List(file("withoutfragment.html") -> ("test.html"))
 -> paradoxValidateInternalLinks
 
 # Now add the path with the fragment, validation should succeed
-> reload
-> set (Compile / paradox / mappings) += (file("withfragment.html") -> ("test.html"))
+> set additionalInternalMappings := List(file("withfragment.html") -> ("test.html"))
 > paradoxValidateInternalLinks
 
 # Now set a base path of /, validation should fail due to /../outside.html not existing
@@ -22,27 +21,32 @@
 -> paradoxValidateInternalLinks
 
 # Now add an /outside.html, but without a fragment, validation should fail
-> set (Compile / paradoxValidateInternalLinks / mappings) += (file("withoutfragment.html") -> ("/outside.html"))
+> set additionalMappings := List(file("withoutfragment.html") -> ("/outside.html"))
 -> paradoxValidateInternalLinks
 
 # Now add an /outside.html, with a fragment, validation should succeed
-> reload
-> set paradoxValidationSiteBasePath := Some("/docs")
-> set (Compile / paradox / mappings) += (file("withfragment.html") -> ("test.html"))
-> set (Compile / paradoxValidateInternalLinks / mappings) += (file("withfragment.html") -> ("/outside.html"))
+> set additionalMappings := List(file("withfragment.html") -> ("/outside.html"))
 > paradoxValidateInternalLinks
 
 # Also try setting the internal link with an absolute path
-> reload
-> set paradoxValidationSiteBasePath := Some("/docs")
-> set (Compile / paradoxValidateInternalLinks / mappings) += (file("withfragment.html") -> ("/docs/test.html"))
-> set (Compile / paradoxValidateInternalLinks / mappings) += (file("withfragment.html") -> ("/outside.html"))
+> set additionalInternalMappings := Nil
+> set additionalMappings += (file("withfragment.html") -> ("/docs/test.html"))
 > paradoxValidateInternalLinks
 
 # Finally, try validating external links, first check that it fails
 -> paradoxValidateLinks
-# Now ignore the link that fails
-> set paradoxValidationIgnorePaths += ("https://www.lightbend.com.*").r
-# The following test will fail if GitHub is down. That's fairly unlikely if we're running a CI build, since CI
-# depends on GitHub being up to run in the first place, and also being up to report the status of the build, etc.
+
+# Now make sure it fails when just the 404ing link is ignored
+> set paradoxValidationIgnorePaths := List(".*thisrepodoesnotexist.*".r)
+-> paradoxValidateLinks
+
+# Now make sure it fails when just the 401ing link is ignored
+> set paradoxValidationIgnorePaths := List("https://lightbend.com".r)
+-> paradoxValidateLinks
+
+# Now ignore both failing links, and it should pass. Note though that passing depends on GitHub being up,
+# since there is a valid link that points to GitHub. If we're running in CI, GitHub being up is an alright
+# assumption to make, given that GitHub triggered the build, and will have to be up to receive the status
+# report
+> set paradoxValidationIgnorePaths := List("https://lightbend.com".r, (".*thisrepodoesnotexist.*").r)
 > paradoxValidateLinks

plugin/src/sbt-test/paradox/validation/withfragment.html

@@ -1,5 +1,6 @@
 <html>
 <body>
 <a id="frag"></a>
+<a name="namefrag"></a>
 </body>
 </html>

project/Dependencies.scala

@@ -25,6 +25,7 @@ object Version {
   val sbtWeb     = "1.4.4"
   val scalatest  = "3.0.8"
   val st4        = "4.1"
+  val jsoup      = "1.12.1"
 }
 
 object Library {
@@ -38,4 +39,5 @@ object Library {
   val sbtWeb     = "com.typesafe.sbt"  % "sbt-web"    % Version.sbtWeb
   val scalatest  = "org.scalatest"    %% "scalatest"  % Version.scalatest
   val st4        = "org.antlr"         % "ST4"        % Version.st4
+  val jsoup      = "org.jsoup"         % "jsoup"      % Version.jsoup
 }