Implement wxr importer

[derpixler]

We have to implement a custom wxr importer for the created wxr export files from single wmpl installation. We could not use the WordPress Importer-Plugin, there is no Hook to parse custom wxr elements.

If wpml2mlp in a Multisite aktiv also there have to exisxts under (Tools/import)[wp-admin/import.php]a section for the wpml2mlp wxr parser.

At the 0.0.1.2 version of wpml2mlp we have turned the xliff export format to the WordPress defauld wxr. On every Post there have Translations that are appended at the post item.

    <wp:translation lang="en" post_id="2401"/>
    <wp:translation lang="de" post_id="2491"/>
    <wp:translation lang="nl" post_id="2071"/>
    <wp:translation lang="es" post_id="2566"/>
    <wp:translation lang="fr" post_id="2593"/>

Our wxr parser have to map the Translations to mlp.

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Subtasks:

• [x] #25 Importer: XML-Parsing
  • [x] Iterators
  • [x] User parser
  • [x] Term parser
  • [x] Post parser
  • [x] Comment parser
• [ ] #49 Importer: Element Filter
  • [ ] Duplicate post filter
  • [ ] Duplicate term filter
  • [ ] Duplicate comment filter
  • [ ] Duplicate user filter
• [ ] #26 Importer: Datawriting
  • [x] User Importer
  • [x] Term Importer
  • [x] Post Importer
  • [x] File importer
  • [x] Comment Importer
• [x] #32 Importer: API
  • [x] Type\ImportUser
  • [x] Type\ImportTerm
  • [x] Type\ImportPost
  • [x] Type\ImportComment
• [ ] Modules: Object worker (connect iterators, parser, filters ( #49 ) and importer)
  • [x] User
  • [x] Terms
  • [x] Posts
  • [x] Comments
• [ ] Module: MLP relation
  • [x] Link posts
  • [ ] Link terms
• [ ] Ancestor resolving
  • [x] resolve post ancestors
  • [x] resolve term ancestors
  • [ ] resolve comment ancestors
• [ ] Relation resolving
  • [x] post/author relations
  • [ ] comment/post relations
  • [x] post/term relations
• [ ] Logging
• [ ] WP-CLI
  • [x] import command
• [ ] DI
  • [ ] Configure DI Container

[bueltge]

https://github.com/humanmade/WordPress-Importer

Helpful, I hope it.

[dnaber-de]

@bueltge The hint about XML pull parsers in McCue's post is a good one.

@derpixler: We could go with a combination of XMLReader and SimpleXML: http://stackoverflow.com/a/1835324/2169046