Initial work on a URL analyzer plugin

lib/nulform/plugins/urlanalyzer.ex

@@ -0,0 +1,51 @@
+defmodule Nulform.Plugins.URLAnalyzer do
+    @moduledoc """
+        This is an example plugin which analyzes URLs on IRC. It scans incoming
+        IRC messages for URLs and analyzes them, returning data about them.
+
+        The algorithm for analyzing URLs is as follows:
+        * Send HEAD request to URL. Store content-length, content-type, and
+          HTTP code.
+        * If an error happened, return the collected data.
+        * If request succeeded and content-type is text/html, issue a GET
+          request to the URL.
+        * Try to find <title> contents from body and return it with other data
+          if found.
+    """
+
+    def run() do
+        run nil
+    end
+
+    def run(parent) do
+        receive do
+            {:nulform, :set_parent, parent} ->
+                :ok = :inets.start()
+
+            {:nulform, :urlanalyze, url, id} ->
+                Kernel.spawn __MODULE__, :run_analyzer, [parent, Kernel.binary_to_list url]
+        end
+
+        run parent
+    end
+
+    def run_analyzer(parent, url) do
+        {:ok, {{_, status, _}, headers, body}} = :httpc.request :head, {url, []}, [], []
+        [content_type | _] = String.split to_binary(headers['content-type']), ";"
+
+        if status != 200 do
+            result = {status, content_type, headers['content-length'], body}
+        else
+            if content_type == "text/html" do
+                {:ok, {{_, status, _}, headers, body}} = :httpc.request url
+            end
+            result = {status, content_type, headers['content_length'], body}
+        end
+
+        parent <- result
+    end
+
+    def find_urls(message) do
+        []
+    end
+end