title: Jenkins Multibranch: Indexing error com.fasterxml.jackson.core.JsonParseException
body: <p>I have different multibranch pipelines configured and triggers based on branches, pull requests and tags from <code>GitHub</code> repositories. </p>
  
  <p>It was working as expected, but recently I couldn't figure out that repository scan is failing during indexing step with below error.</p>
  
  <p>I am new to <code>Jenkins</code> and plugins, need some guidance.</p>
  
  <pre><code>ERROR: [Mon Feb 18 06:14:37 UTC 2019] Could not update folder level actions from source HASH
  
  com.fasterxml.jackson.core.JsonParseException: Unexpected character ('&lt;' (code 60)): expected a valid value (number, String, array, object, 'true', 'false' or 'null')
   at [Source: (StringReader); line: 1, column: 2]
      at com.fasterxml.jackson.core.JsonParser._constructError(JsonParser.java:1804)
      at com.fasterxml.jackson.core.base.ParserMinimalBase._reportError(ParserMinimalBase.java:693)
      at com.fasterxml.jackson.core.base.ParserMinimalBase._reportUnexpectedChar(ParserMinimalBase.java:591)
      at com.fasterxml.jackson.core.json.ReaderBasedJsonParser._handleOddValue(ReaderBasedJsonParser.java:1902)
      at com.fasterxml.jackson.core.json.ReaderBasedJsonParser.nextToken(ReaderBasedJsonParser.java:757)
      at com.fasterxml.jackson.databind.ObjectMapper._initForReading(ObjectMapper.java:4141)
      at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4000)
      at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3004)
      at org.kohsuke.github.Requester.parse(Requester.java:629)
  
  Caused: org.kohsuke.github.HttpException: Server returned HTTP response code: 200, message: 'OK' for URL: GITHUB REPO URL
      at org.kohsuke.github.Requester.parse(Requester.java:646)
      at org.kohsuke.github.Requester.parse(Requester.java:607)
      at org.kohsuke.github.Requester._to(Requester.java:285)
      at org.kohsuke.github.Requester.to(Requester.java:247)
      at org.kohsuke.github.GitHub.getRepository(GitHub.java:475)
      at org.jenkinsci.plugins.github_branch_source.GitHubSCMSource.retrieveActions(GitHubSCMSource.java:1669)
      at jenkins.scm.api.SCMSource.fetchActions(SCMSource.java:765)
      at jenkins.branch.MultiBranchProject.computeChildren(MultiBranchProject.java:591)
      at com.cloudbees.hudson.plugins.folder.computed.ComputedFolder.updateChildren(ComputedFolder.java:277)
      at com.cloudbees.hudson.plugins.folder.computed.FolderComputation.run(FolderComputation.java:165)
      at jenkins.branch.MultiBranchProject$BranchIndexing.run(MultiBranchProject.java:1025)
      at hudson.model.ResourceController.execute(ResourceController.java:97)
      at hudson.model.Executor.run(Executor.java:429)
  [Mon Feb 18 06:14:37 UTC 2019] Finished branch indexing. Indexing took 0.27 sec
  </code></pre>