Handle (log/fallback) connection errors when fetching well-known/matrix/client URLs

Author: mk-fg

lib/matrix_client/client.ex

@@ -449,14 +449,14 @@ defmodule M51.MatrixClient.Client do
 
     wellknown_url = "https://" <> hostname <> "/.well-known/matrix/client"
 
-    case httpoison.get!(wellknown_url) do
-      %HTTPoison.Response{status_code: 200, body: body} ->
+    case httpoison.get(wellknown_url) do
+      {:ok, %HTTPoison.Response{status_code: 200, body: body}} ->
         data = Jason.decode!(body)
         base_url = data["m.homeserver"]["base_url"]
         Logger.debug("Well-known request for #{wellknown_url} yielded #{base_url}")
         base_url
 
-      %HTTPoison.Response{status_code: 404} ->
+      {:ok, %HTTPoison.Response{status_code: 404}} ->
         base_url = "https://" <> hostname
 
         Logger.debug(
@@ -466,7 +466,7 @@ defmodule M51.MatrixClient.Client do
 
         base_url
 
-      res ->
+      {:ok, res} ->
         # The next call will probably fail, but this spares error handling in this one.
         base_url = "https://" <> hostname
 
@@ -476,6 +476,18 @@ defmodule M51.MatrixClient.Client do
         )
 
         base_url
+
+      {:error, %HTTPoison.Error{reason: err}} ->
+        # Treat this in the same way as HTTP error codes above - perm error and fallback
+        base_url = "https://" <> hostname
+
+        Logger.warn(
+          "Well-known request for #{wellknown_url} failed" <>
+            " with connection error [#{err}]. Falling back to #{base_url}"
+        )
+
+        base_url
+
     end
   end
 

test/format/common_test.exs

@@ -117,21 +117,21 @@ defmodule M51.FormatTest do
 
   test "Matrix link to IRC" do
     MockHTTPoison
-    |> expect(:get!, 4, fn url ->
+    |> expect(:get, 4, fn url ->
       assert url == "https://example.org/.well-known/matrix/client"
 
-      %HTTPoison.Response{
+      {:ok, %HTTPoison.Response{
         status_code: 200,
         body: ~s({"m.homeserver": {"base_url": "https://api.example.org"}})
-      }
+      }}
     end)
-    |> expect(:get!, 1, fn url ->
+    |> expect(:get, 1, fn url ->
       assert url == "https://homeserver.org/.well-known/matrix/client"
 
-      %HTTPoison.Response{
+      {:ok, %HTTPoison.Response{
         status_code: 200,
         body: ~s({"m.homeserver": {"base_url": "https://api.homeserver.org"}})
-      }
+      }}
     end)
 
     assert M51.Format.matrix2irc(~s(<a href="https://example.org">foo</a>)) ==
@@ -178,13 +178,13 @@ defmodule M51.FormatTest do
 
   test "Matrix link to IRC (404 on well-known)" do
     MockHTTPoison
-    |> expect(:get!, 1, fn url ->
+    |> expect(:get, 1, fn url ->
       assert url == "https://example.org/.well-known/matrix/client"
 
-      %HTTPoison.Response{
+      {:ok, %HTTPoison.Response{
         status_code: 404,
         body: ~s(this is not JSON)
-      }
+      }}
     end)
 
     assert M51.Format.matrix2irc(~s(<img src="mxc://example.org/foo" />)) ==

test/matrix_client/client_test.exs

@@ -32,9 +32,9 @@ defmodule M51.MatrixClient.ClientTest do
 
   def expect_login(mock_httpoison) do
     mock_httpoison
-    |> expect(:get!, fn url ->
+    |> expect(:get, fn url ->
       assert url == "https://matrix.example.org/.well-known/matrix/client"
-      %HTTPoison.Response{status_code: 404, body: "Error 404"}
+      {:ok, %HTTPoison.Response{status_code: 404, body: "Error 404"}}
     end)
     |> expect(:get!, fn url ->
       assert url == "https://matrix.example.org/_matrix/client/r0/login"
@@ -81,15 +81,15 @@ defmodule M51.MatrixClient.ClientTest do
 
   test "connection to non-homeserver", %{sup_pid: sup_pid} do
     MockHTTPoison
-    |> expect(:get!, fn url ->
+    |> expect(:get, fn url ->
       assert url == "https://example.org/.well-known/matrix/client"
 
-      %HTTPoison.Response{
+      {:ok, %HTTPoison.Response{
         status_code: 404,
         body: """
           Error 404
         """
-      }
+      }}
     end)
     |> expect(:get!, fn url ->
       assert url == "https://example.org/_matrix/client/r0/login"
@@ -119,15 +119,15 @@ defmodule M51.MatrixClient.ClientTest do
 
   test "connection without well-known", %{sup_pid: sup_pid} do
     MockHTTPoison
-    |> expect(:get!, fn url ->
+    |> expect(:get, fn url ->
       assert url == "https://matrix.example.org/.well-known/matrix/client"
 
-      %HTTPoison.Response{
+      {:ok, %HTTPoison.Response{
         status_code: 404,
         body: """
           Error 404
         """
-      }
+      }}
     end)
     |> expect(:get!, fn url ->
       assert url == "https://matrix.example.org/_matrix/client/r0/login"
@@ -192,8 +192,8 @@ defmodule M51.MatrixClient.ClientTest do
 
   test "connection with well-known", %{sup_pid: sup_pid} do
     MockHTTPoison
-    |> expect(:get!, fn _url ->
-      %HTTPoison.Response{
+    |> expect(:get, fn _url ->
+      {:ok, %HTTPoison.Response{
         status_code: 200,
         body: """
           {
@@ -202,7 +202,7 @@ defmodule M51.MatrixClient.ClientTest do
             }
           }
         """
-      }
+      }}
     end)
     |> expect(:get!, fn url ->
       assert url == "https://matrix.example.com/_matrix/client/r0/login"
@@ -270,15 +270,15 @@ defmodule M51.MatrixClient.ClientTest do
 
   test "connection without password flow", %{sup_pid: sup_pid} do
     MockHTTPoison
-    |> expect(:get!, fn url ->
+    |> expect(:get, fn url ->
       assert url == "https://matrix.example.org/.well-known/matrix/client"
 
-      %HTTPoison.Response{
+      {:ok, %HTTPoison.Response{
         status_code: 404,
         body: """
           Error 404
         """
-      }
+      }}
     end)
     |> expect(:get!, fn url ->
       assert url == "https://matrix.example.org/_matrix/client/r0/login"
@@ -314,15 +314,15 @@ defmodule M51.MatrixClient.ClientTest do
 
   test "connection with invalid password", %{sup_pid: sup_pid} do
     MockHTTPoison
-    |> expect(:get!, fn url ->
+    |> expect(:get, fn url ->
       assert url == "https://matrix.example.org/.well-known/matrix/client"
 
-      %HTTPoison.Response{
+      {:ok, %HTTPoison.Response{
         status_code: 404,
         body: """
           Error 404
         """
-      }
+      }}
     end)
     |> expect(:get!, fn url ->
       assert url == "https://matrix.example.org/_matrix/client/r0/login"
@@ -374,9 +374,9 @@ defmodule M51.MatrixClient.ClientTest do
 
   test "registration", %{sup_pid: sup_pid} do
     MockHTTPoison
-    |> expect(:get!, fn url ->
+    |> expect(:get, fn url ->
       assert url == "https://matrix.example.org/.well-known/matrix/client"
-      %HTTPoison.Response{status_code: 404, body: "Error 404"}
+      {:ok, %HTTPoison.Response{status_code: 404, body: "Error 404"}}
     end)
     |> expect(:post!, fn url, body ->
       assert url == "https://matrix.example.org/_matrix/client/r0/register"

test/matrix_client/poller_test.exs

@@ -1146,23 +1146,23 @@ defmodule M51.MatrixClient.PollerTest do
     test "messages (is_backlog=#{is_backlog})" do
       if unquote(is_backlog) do
         MockHTTPoison
-        |> expect(:get!, 0, fn url ->
+        |> expect(:get, 0, fn url ->
           assert url == "https://matrix.org/.well-known/matrix/client"
 
-          %HTTPoison.Response{
+          {:ok, %HTTPoison.Response{
             status_code: 200,
             body: ~s({"m.homeserver": {"base_url": "https://matrix-client.matrix.org"}})
-          }
+          }}
         end)
       else
         MockHTTPoison
-        |> expect(:get!, 5, fn url ->
+        |> expect(:get, 5, fn url ->
           assert url == "https://matrix.org/.well-known/matrix/client"
 
-          %HTTPoison.Response{
+          {:ok, %HTTPoison.Response{
             status_code: 200,
             body: ~s({"m.homeserver": {"base_url": "https://matrix-client.matrix.org"}})
-          }
+          }}
         end)
       end