Add integration tests using httpx

tests/test_using_httpx.py

@@ -0,0 +1,49 @@
+import pytest
+import httpx
+
+import stringdb
+
+
+@pytest.fixture(scope="session")
+def api():
+    with httpx.Client() as client:
+        yield stringdb.API(client=client)
+
+
+def test_api_with_httpx_client(api):
+    assert api.client is not None
+
+
+def test_api_current_version(api):
+    assert api.version == stringdb.CURRENT_VERSION
+
+
+def test_get_string_ids(api):
+    identifiers = ["edin", "attc"]
+    species = 7227
+
+    response = api.get_string_ids(identifiers, species)
+
+    for result in response:
+        assert result["queryItem"] in identifiers
+        assert result["ncbiTaxonId"] == species
+        assert "stringId" in result.keys()
+
+
+def test_get_interaction_partners(api):
+    identifiers = ["7227.FBpp0074940", "7227.FBpp0297062"]
+    species = 7227
+
+    response = api.get_interaction_partners(identifiers, species)
+
+    assert len(response) > 1
+
+
+def test_get_interaction_partners_limited(api):
+    identifiers = ["7227.FBpp0074940", "7227.FBpp0297062"]
+    species = 7227
+    limit = 1
+
+    response = api.get_interaction_partners(identifiers, species, limit)
+
+    assert len(response) == limit * len(identifiers)