Implement restricting the IP protocol version for /dns4 and /dns6 multiaddr items in the HTTPx backend

Author: ntninja

CHANGELOG.md

@@ -9,6 +9,7 @@ Bugfixes:
 
  * The value of the `timeout` parameter on `ipfshttpclient.{connect,Client}` is no longer ignored when using the `requests` HTTP backend (default)
     * (The per-API-call `timeout` parameter was unaffected by this.)
+ * The HTTPx HTTP backend now properly applies address family restrictions encoded as part of the daemon MultiAddr (needed minor upstream change)
 
 py-ipfs-http-client 0.6.0 (30.06.2020)
 --------------------------------------

ipfshttpclient/http_httpx.py

@@ -7,8 +7,8 @@
 import math
 import socket
 import typing as ty
-import warnings
 
+import httpcore
 import httpx
 
 from . import encoding
@@ -26,7 +26,7 @@
 	import typing_extensions
 
 	# By using the precise types from HTTPx we'll also get type errors if our
-	# types become somehow incompatible with the one from that library
+	# types become somehow incompatible with the ones from that library
 	RequestArgs = typing_extensions.TypedDict("RequestArgs", {
 		"auth": "httpx._types.AuthTypes",
 		"cookies": "httpx._types.CookieTypes",
@@ -75,9 +75,10 @@ def map_args_to_httpx(
 
 
 class ClientSync(ClientSyncBase[httpx.Client]):
-	__slots__ = ("_session_base", "_session_kwargs")
+	__slots__ = ("_session_base", "_session_kwargs", "_session_laddr")
 	_session_base: "httpx._types.URLTypes"
 	_session_kwargs: RequestArgs
+	_session_laddr: ty.Optional[str]
 
 	def _init(self, addr: addr_t, base: str, *,  # type: ignore[no-any-unimported]
 	          auth: auth_t,
@@ -90,12 +91,15 @@ def _init(self, addr: addr_t, base: str, *,  # type: ignore[no-any-unimported]
 		host_numeric: bool
 		base_url, family, host_numeric = multiaddr_to_url_data(addr, base)
 
-		#FIXME once https://github.com/encode/httpcore/pull/100 is released
-		if family != socket.AF_UNSPEC and not host_numeric:
-			warnings.warn(
-				"Restricting the address family on name lookups is not yet supported by HTTPx",
-				UserWarning
-			)
+		self._session_laddr = None
+		if family != socket.AF_UNSPEC:
+			if family == socket.AF_INET:
+				self._session_laddr = "0.0.0.0"
+			elif family == socket.AF_INET6:
+				self._session_laddr = "::"
+			else:
+				assert False, ("multiaddr_to_url_data should only return a socket "
+				               "address family of AF_INET, AF_INET6 or AF_UNSPEC")
 
 		self._session_base = base_url
 		self._session_kwargs = map_args_to_httpx(
@@ -107,7 +111,18 @@ def _init(self, addr: addr_t, base: str, *,  # type: ignore[no-any-unimported]
 		)
 
 	def _make_session(self) -> httpx.Client:
-		return httpx.Client(**self._session_kwargs, base_url=self._session_base)
+		connection_pool = httpcore.SyncConnectionPool(
+			local_address = self._session_laddr,
+			
+			#XXX: Argument values duplicated from httpx._client.Client._init_transport:
+			keepalive_expiry          = 5.0,  #XXX: Value duplicated from httpx._client.KEEPALIVE_EXPIRY
+			max_connections           = 100,  #XXX: Value duplicated from httpx._config.DEFAULT_LIMITS
+			max_keepalive_connections = 20,   #XXX: Value duplicated from httpx._config.DEFAULT_LIMITS
+			ssl_context               = httpx.create_ssl_context(trust_env=True),
+		)
+		return httpx.Client(**self._session_kwargs,
+		                    base_url  = self._session_base,
+		                    transport = connection_pool)
 
 	def _do_raise_for_status(self, response: httpx.Response) -> None:
 		try:

test/unit/test_http_httpx.py

@@ -47,10 +47,10 @@
 def test_map_args_to_httpx(kwargs, expected):
 	assert ipfshttpclient.http_httpx.map_args_to_httpx(**kwargs) == expected
 
-@pytest.mark.parametrize("args,kwargs,expected_kwargs,expected_base", [
+@pytest.mark.parametrize("args,kwargs,expected_kwargs,expected_base,expected_laddr", [
 	(("/dns/localhost/tcp/5001/http", "api/v0"), {}, {
 		"params": [("stream-channels", "true")],
-	}, "http://localhost:5001/api/v0/"),
+	}, "http://localhost:5001/api/v0/", None),
 	
 	(("/dns6/ietf.org/tcp/443/https", "/base/"), {
 		"auth": ("user", "pass"),
@@ -59,15 +59,15 @@ def test_map_args_to_httpx(kwargs, expected):
 		"offline": True,
 		"timeout": (math.inf, math.inf),
 	}, {
-		#XXX: This should also store the expected address family somewhere
 		"auth": ("user", "pass"),
 		"cookies": cookiejar,
 		"headers": {"name": "value"},
 		"params": [("offline", "true"), ("stream-channels", "true")],
 		"timeout": (None, None, None, None),
-	}, "https://ietf.org:443/base/"),
+	}, "https://ietf.org:443/base/", "::"),
 ])
-def test_client_args_to_session_kwargs(args, kwargs, expected_kwargs, expected_base):
+def test_client_args_to_session_kwargs(args, kwargs, expected_kwargs, expected_base, expected_laddr):
 	client = ipfshttpclient.http_httpx.ClientSync(*args, **kwargs)
 	assert client._session_kwargs == expected_kwargs
-	assert client._session_base == expected_base
+	assert client._session_base == expected_base
+	assert client._session_laddr == expected_laddr

tox.ini

@@ -3,7 +3,7 @@
 minversion = 3.3
 envlist =
 	py3,
-	pypy3,
+	py3-httpx,
 	styleck,
 	typeck
 
@@ -45,7 +45,7 @@ deps =
 [testenv:py3-httpx]
 deps =
 	{[testenv]deps}
-	httpx (~=0.13.0)
+	httpx (~=0.14.0)  # Including its httpcore 0.10.* dependency
 setenv =
 	{[testenv]setenv}
 	PY_IPFS_HTTP_CLIENT_PREFER_HTTPX = yes
@@ -69,7 +69,7 @@ skip_install = true
 deps =
 	mypy ~= 0.782
 	pytest ~= 5.0
-	httpx ~= 0.13.0
+	httpx ~= 0.14.0
 commands =
 	mypy --config-file=tox.ini {posargs} -p ipfshttpclient