ref: now caching OSM images

.gitignore

@@ -27,3 +27,4 @@ erl_crash.dump
 /pictures/*
 /send_mention.sh
 /release.sh
+/cache

config/dev.exs

@@ -34,6 +34,7 @@ config :logger, :console, format: "[$level] $message\n"
 config :phoenix, :stacktrace_depth, 20
 
 config :wwwtech, storage_path: "/home/ckruse/sites/wwwtech/pictures"
+config :wwwtech, cache_path: "/home/ckruse/sites/wwwtech/cache"
 
 # Configure your database
 config :wwwtech, Wwwtech.Repo,

config/prod.exs

@@ -25,6 +25,7 @@ config :logger, :out_log,
 
 
 config :wwwtech, storage_path: "/home/ckruse/pictures_wwwtech"
+config :wwwtech, cache_path: "/home/ckruse/cache_wwwtech"
 
 # ## SSL Support
 #

web/controllers/cache_controller.ex

@@ -0,0 +1,48 @@
+defmodule Wwwtech.CacheController do
+  use Wwwtech.Web, :controller
+  use Wwwtech.Web, :web_controller
+
+  alias Wwwtech.Note
+  alias Wwwtech.Picture
+  alias Wwwtech.Article
+
+  plug :set_mention_header
+  plug :set_caching_headers
+
+  @allowed_hosts [
+    ~r/^https?:\/\/staticmap.openstreetmap.de/
+  ]
+
+  def show(conn, %{"url" => url}) do
+    is_allowed = Enum.any?(@allowed_hosts, fn(x) -> Regex.match?(x, url) end)
+
+    if is_allowed do
+      send_cached_reply(conn, url)
+    else
+      conn |> put_status(403) |> text("Access forbidden")
+    end
+  end
+
+  defp send_cached_reply(conn, url) do
+    file_name = url2filename(url)
+
+    if not File.exists?(file_name) do
+      get_url(url, file_name)
+    end
+
+    send_file(conn, 200, file_name)
+  end
+
+  defp get_url(url, cache_file) do
+    rsp = HTTPotion.get(url)
+    if HTTPotion.Response.success?(rsp) do
+      File.write!(cache_file, rsp.body)
+    else
+      raise "Error getting URL"
+    end
+  end
+
+  defp url2filename(url) do
+    Application.get_env(:wwwtech, :cache_path) <> "/" <> Regex.replace(~r/[^a-z0-9A-Z]/, url, "_")
+  end
+end

web/router.ex

@@ -35,6 +35,8 @@ defmodule Wwwtech.Router do
 
     resources "/pictures", PictureController
     get "/pictures.atom", PictureController, :index_atom
+
+    get "/cache", CacheController, :show
   end
 
   scope "/", Wwwtech do

web/templates/picture/picture.html.eex

@@ -25,7 +25,7 @@ p_type = if assigns[:type], do: assigns[:type], else: :thumbnail
   </div>
 
   <%= if assigns[:index] == nil and assigns[:exif] != nil and @exif[:gps_latitude] != nil and @exif[:gps_longitude] != nil do %>
-    <a class="osm" href="http://www.openstreetmap.org/?lat=<%= to_degrees(@exif[:gps_latitude], @exif[:gps_latitude_ref]) %>&amp;lon=<%= to_degrees(@exif[:gps_longitude], @exif[:gps_longitude_ref]) %>&amp;mlat=<%= to_degrees(@exif[:gps_latitude], @exif[:gps_latitude_ref]) %>&amp;mlon=<%= to_degrees(@exif[:gps_longitude], @exif[:gps_longitude_ref]) %>&amp;zoom=16"><img src="http://staticmap.openstreetmap.de/staticmap.php?center=<%= to_degrees(@exif[:gps_latitude], @exif[:gps_latitude_ref]) %>,<%= to_degrees(@exif[:gps_longitude], @exif[:gps_longitude_ref]) %>&amp;markers=<%= to_degrees(@exif[:gps_latitude], @exif[:gps_latitude_ref]) %>,<%= to_degrees(@exif[:gps_longitude], @exif[:gps_longitude_ref]) %>&amp;zoom=16&amp;size=640x480"></a>
+    <a class="osm" href="http://www.openstreetmap.org/?lat=<%= to_degrees(@exif[:gps_latitude], @exif[:gps_latitude_ref]) %>&amp;lon=<%= to_degrees(@exif[:gps_longitude], @exif[:gps_longitude_ref]) %>&amp;mlat=<%= to_degrees(@exif[:gps_latitude], @exif[:gps_latitude_ref]) %>&amp;mlon=<%= to_degrees(@exif[:gps_longitude], @exif[:gps_longitude_ref]) %>&amp;zoom=16"><img src="<%= cache_path(@conn, :show, url: "http://staticmap.openstreetmap.de/staticmap.php?center=#{to_degrees(@exif[:gps_latitude], @exif[:gps_latitude_ref])},#{to_degrees(@exif[:gps_longitude], @exif[:gps_longitude_ref])}&markers=#{to_degrees(@exif[:gps_latitude], @exif[:gps_latitude_ref])},#{to_degrees(@exif[:gps_longitude], @exif[:gps_longitude_ref])}&zoom=16&size=640x480") %>"></a>
   <% end %>
 
   <%= if assigns[:index] == nil and @picture.posse do %>