1 files changed, 50 insertions, 0 deletions
diff --git a/scripts/lib/glfm/render_static_html.rb b/scripts/lib/glfm/render_static_html.rb
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index 00000000000..d533e586fe1
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+++ b/scripts/lib/glfm/render_static_html.rb
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+# frozen_string_literal: true
+
+require_relative 'constants'
+require_relative 'shared'
+
+# Purpose:
+# - Reads a set of markdown examples from a hash which has been serialized to disk
+# - Converts each example to static HTML using the `markdown` helper
+# - Writes the HTML for each example to a hash which is serialized to disk
+#
+# It should be invoked via `rails runner` from the Rails root directory.
+# It is intended to be invoked from the `update_example_snapshots.rb` script class.
+module Glfm
+  class RenderStaticHtml
+    include Constants
+    include Shared
+
+    def process
+      markdown_yml_path = ARGV[0]
+      markdown_hash = YAML.load_file(markdown_yml_path)
+
+      # NOTE: We COULD parallelize this loop like the Javascript WYSIWYG example generation does,
+      # but it wouldn't save much time. Most of the time is spent loading the Rails environment
+      # via `rails runner`. In initial testing, this loop only took ~7 seconds while the entire
+      # script took ~20 seconds. Unfortunately, there's no easy way to execute
+      # `ApplicationController.helpers.markdown` without using `rails runner`
+      static_html_hash = markdown_hash.transform_values do |markdown|
+        ApplicationController.helpers.markdown(markdown)
+      end
+
+      static_html_tempfile_path = Dir::Tmpname.create(STATIC_HTML_TEMPFILE_BASENAME) do |path|
+        tmpfile = File.open(path, 'w')
+        YAML.dump(static_html_hash, tmpfile)
+        tmpfile.close
+      end
+
+      # Write the path to the output file to stdout
+      print static_html_tempfile_path
+    end
+  end
+end
+
+# current_user must be in global scope for `markdown` helper to work. Currently it's not supported
+# to pass it in the context.
+def current_user
+  # TODO: This will likely need to be a more realistic user object for some of the GLFM examples
+  User.new
+end
+
+Glfm::RenderStaticHtml.new.process