add views/post-exporter

4 files changed, 253 insertions, 32 deletions

diff --git a/src/guff/disposition.cr b/src/guff/disposition.cr
new file mode 100644
index 0000000..96354b0
--- /dev/null
+++ b/src/guff/disposition.cr
@@ -0,0 +1,12 @@
+module Guff::Disposition
+  HEADER = "content-disposition"
+  FORMAT = "attachment; filename=\"%s\"; filename*=UTF-8''%s"
+
+  def self.header(name : String) : String
+    FORMAT % [name.gsub(/[%";]+/, "_"), URI.escape(name)]
+  end
+
+  def self.set(headers : HTTP::Headers, name : String)
+    headers[HEADER] = header(name)
+  end
+end
diff --git a/src/guff/handlers.cr b/src/guff/handlers.cr
index d6c526f..20c44ea 100644
--- a/src/guff/handlers.cr
+++ b/src/guff/handlers.cr
@@ -396,11 +396,12 @@ module Guff::Handlers
         path = context.request.path.not_nil!
 
         if /\/$/.match(path)
-          # TODO: render page
+          # send headers
           context.response.headers["x-frame-options"] = "SAMEORIGIN"
           context.response.content_type = "text/html; charset=utf-8"
           context.response.status_code = 200
 
+          # render page
           Views::Posts::Project.new(@context, r).to_s(context.response)
         else
           # redirect to project
@@ -501,11 +502,12 @@ module Guff::Handlers
     def call(context : HTTP::Server::Context)
       site_id, r = find(context.request)
       if site_id && r
-        # TODO: render page
+        # send headers
         context.response.headers["x-frame-options"] = "SAMEORIGIN"
         context.response.content_type = "text/html; charset=utf-8"
         context.response.status_code = 200
 
+        # render page
         Views::Blog::List.new(@context, site_id, r).to_s(context.response)
       else
         # unknown page
@@ -742,6 +744,48 @@ module Guff::Handlers
     end
   end
 
+  class ExportPostsAPIHandler < AuthenticatedHandler
+    def initialize(context : Context)
+      super(context, %w{admin editor})
+    end
+
+    def authenticated_call(context : HTTP::Server::Context)
+      req_path = context.request.path.not_nil!
+
+      if matching_request?(context.request.method, req_path) &&
+         valid_origin_headers?(context.request.headers)
+
+        # parse request parameters and get site_id
+        params = HTTP::Params.parse(context.request.body.not_nil!)
+        site_id = params["site_id"].not_nil!.to_i64
+
+        # create exporter
+        exporter = Views::PostExporter.new(
+          context: @context,
+          site_id: site_id,
+        )
+
+        # build response
+        context.response.headers["x-frame-options"] = "SAMEORIGIN"
+        context.response.status_code = 200
+        context.response.content_type = exporter.content_type
+        Disposition.set(context.response.headers, exporter.file_name)
+
+        # send response
+        exporter.to_s(context.response)
+      else
+        # not a matching request
+        call_next(context)
+      end
+    end
+
+    PATH_RE = %r{^/guff/api/export/posts}
+
+    private def matching_request?(method, path)
+      (method == "POST") && PATH_RE.match(path)
+    end
+  end
+
   HANDLERS = [{
     :dev  => true,
     :id   => :stub,
@@ -787,6 +831,11 @@ module Guff::Handlers
     :dev  => false,
     :id   => :file_api,
   }, {
+    # NOTE: special handler for api/export/posts, should load
+    # before api handler
+    :dev  => false,
+    :id   => :export_posts_api,
+  }, {
     :dev  => false,
     :id   => :api,
   }, {
@@ -822,6 +871,8 @@ module Guff::Handlers
       SessionHandler.new(context)
     when :file_api
       FileAPIHandler.new(context)
+    when :export_posts_api
+      ExportPostsAPIHandler.new(context)
     when :api
       APIHandler.new(context)
     when :assets
diff --git a/src/guff/views/post-exporter.cr b/src/guff/views/post-exporter.cr
new file mode 100644
index 0000000..0558c39
--- /dev/null
+++ b/src/guff/views/post-exporter.cr
@@ -0,0 +1,151 @@
+#
+# WXR Blog Post Exporter
+#
+# Based on the information at the following URLs:
+#   https://devtidbits.com/2011/03/16/the-wordpress-extended-rss-wxr-exportimport-xml-document-format-decoded-and-explained/
+#   http://wpcandy.com/made/the-sample-post-collection/
+#
+class Guff::Views::PostExporter
+  TEMPLATES = Template::Cache.new({
+    "head" => %{
+      <?xml version="1.0" encoding="UTF-8"?>
+      <!-- Generated by Guff %{version | h} on %{date_iso8601 | h}. -->
+
+      <rss version="2.0"
+        xmlns:content="http://purl.org/rss/1.0/modules/content/"
+        xmlns:wfw="http://wellformedweb.org/CommentAPI/"
+        xmlns:dc="http://purl.org/dc/elements/1.1/"
+        xmlns:wp="http://wordpress.org/export/1.0/"
+      >
+        <channel>
+          <title>%{name | h}</title>
+          <link>%{link | h}</link>
+          <description>%{text | h}</description>
+          <pubDate>%{date_rfc2822 | h}</pubDate>
+          <generator>https://guff.pablotron.org/?v=%{version | h}</generator>
+          <language>%{lang | h}</language>
+          <wp:wxr_version>1.0</wp:wxr_version>
+          <wp:base_site_url>%{link | h}</wp:base_site_url>
+          <wp:base_blog_url>%{link | h}</wp:base_blog_url>
+    }.strip,
+
+    "head_tag" => %{
+      <wp:tag>
+        <wp:tag_slug>%{tag | h}</wp:tag_slug>
+        <wp:tag_name>%{tag | h}</wp:tag_name>
+      </wp:tag>
+    }.strip,
+
+    "item_tag" => %{
+      <category domain="tag">%{tag | h}</category>
+    }.strip,
+
+    "item" => %{
+      <item>
+        %{tags}
+        <title>%{name | h}</title>
+        <link>%{link | h}</link>
+        <guid isPermaLink="false">%{link | h}</guid>
+        <description></description>
+        <content:encoded>%{body | h}</content:encoded>
+        <excerpt:encoded></excerpt:encoded>
+        <wp:post_id>%{post_id | h}</wp:post_id>
+        <wp:post_date>%{posted_at_text | h}</wp:post_date>
+        <wp:post_date_gmt>%{posted_at | h}</wp:post_date_gmt>
+        <wp:comment_status>closed</wp:comment_status>
+        <wp:ping_status>closed</wp:ping_status>
+        <wp:post_name>%{slug | h}</wp:post_name>
+        <wp:status>publish</wp:status>
+        <wp:post_parent>0</wp:post_parent>
+        <wp:menu_order>0</wp:menu_order>
+        <wp:post_type>post</wp:post_type>
+        <wp:post_password></wp:post_password>
+      </item>
+    },
+
+    "foot" => %{
+        </channel>
+      </rss>
+    }.strip,
+  })
+
+  # TODO: add additional export options
+  def initialize(
+    @context : Context,
+    @site_id : Int64,
+  )
+  end
+
+  # FIXME: language should be specified on a per-site basis
+  LANG = "en-US"
+
+  # FIXME: check this
+  RFC2822 = Time::Format.new("%c %z")
+
+  EMPTY_HASH = {} of String => String
+
+  def to_s(io)
+    # cache current timestamp
+    now = Time.now
+
+    # write header
+    io << TEMPLATES["head"].run({
+      "version"       => Guff::VERSION,
+      "lang"          => LANG,
+
+      # timestamps
+      "date_rfc2822"  => RFC2822.format(now),
+      "date_iso8601"  => ISO8601.format(now),
+
+      # TODO: site name, link, and description
+      "name"          => "Site Name",
+      "link"          => "https://example.com/",
+      "text"          => "Some description of this blog."
+    })
+
+    # TODO: write tags used by blog posts
+
+    # write posts
+    done, page = false, 0_i32
+    until done
+      page += 1
+      r = @context.models.blog.find(
+        site_id: @site_id,
+        page:    page
+      )
+
+      if r.rows.size > 0
+        r.rows.each do |row|
+          io << TEMPLATES["item"].run(row.merge({
+            "tags" => "",
+            "link" => "/todo/" + row["slug"],
+          }))
+        end
+      else
+        done = true
+      end
+    end
+
+    # write footer
+    io << TEMPLATES["foot"].run(EMPTY_HASH)
+  end
+
+  CONTENT_TYPE = "text/xml; charset=utf-8"
+
+  def content_type
+    CONTENT_TYPE
+  end
+
+  # NOTE: wordpress uses name.wordpress.YYYY-MM-DD.xml
+  FILE_NAME_FORMAT = "%s-posts-%s.xml"
+
+  FILE_NAME_TIME_FORMAT = Time::Format.new("%Y%m%d-%H%M%S")
+
+  def file_name
+    site = @context.models.site.get(site_id: @site_id)
+    FILE_NAME_FORMAT % [
+      site["name"].as(String),
+      FILE_NAME_TIME_FORMAT.format(Time.now),
+    ]
+  end
+end
diff --git a/src/views/panes/settings/import.ecr b/src/views/panes/settings/import.ecr
index 5201e77..2cfa7ad 100644
--- a/src/views/panes/settings/import.ecr
+++ b/src/views/panes/settings/import.ecr
@@ -103,36 +103,43 @@
         >WXR</a> format.
       </p>
 
-      <div class='form-group'>
-        <label for='export-site'>
-          Source Site
-        </label>
-
-        <select
-          id='export-site'
-          class='form-control'
-          title='Choose source site.'
-          aria-describedby='export-site-help'
-        ><%=
-          site_options
-        %></select>
-
-        <p id='export-site-help' class='help-block'>
-          Source site of blog posts to export.
-        </p>
-      </div><!-- form-group -->
-
-      <div class='form-group'>
-        <a
-          href='#'
-          id='export-posts'
-          class='btn btn-primary'
-          title='Export blog posts to file in WXR format.'
-        >
-          <i class='fa fa-download'></i>
-          Export Blog Posts
-        </a>
-      </div><!-- form-group -->
+      <form
+        id='export-posts-form'
+        method='post'
+        action='../guff/api/export/posts'
+      >
+        <div class='form-group'>
+          <label for='export-site'>
+            Source Site
+          </label>
+
+          <select
+            id='export-site'
+            name='site_id'
+            class='form-control'
+            title='Choose source site.'
+            aria-describedby='export-site-help'
+          ><%=
+            site_options
+          %></select>
+
+          <p id='export-site-help' class='help-block'>
+            Source site of blog posts to export.
+          </p>
+        </div><!-- form-group -->
+
+        <div class='form-group'>
+          <a
+            href='#'
+            id='export-posts'
+            class='btn btn-primary'
+            title='Export blog posts to file in WXR format.'
+          >
+            <i class='fa fa-download'></i>
+            Export Blog Posts
+          </a>
+        </div><!-- form-group -->
+      </form>
     </div><!-- panel-body -->
   </div><!-- panel -->
 </div><!-- tab-pane -->