Fix network handling

src/nile/common.py

@@ -28,25 +28,35 @@
     # subject to change
     "0x041a78e741e5af2fec34b695679bc6891742439f7afb8484ecd7766661ad02bf"
 )
+DEFAULT_GATEWAYS = {
+    "localhost": "http://127.0.0.1:5050/",
+    "goerli2": "https://alpha4-2.starknet.io",
+    "integration": "https://external.integration.starknet.io",
+}
 
 
 def get_gateways():
     """Get the StarkNet node details."""
-    try:
+    if os.path.exists(NODE_FILENAME):
         with open(NODE_FILENAME, "r") as f:
             gateway = json.load(f)
-            return gateway
-
-    except FileNotFoundError:
-        with open(NODE_FILENAME, "w") as f:
-            networks = {
-                "localhost": "http://127.0.0.1:5050/",
-                "goerli2": "https://alpha4-2.starknet.io",
-                "integration": "https://external.integration.starknet.io",
-            }
-            f.write(json.dumps(networks, indent=2))
-
-            return networks
+            gateways = {**DEFAULT_GATEWAYS, **gateway}
+            return gateways
+    else:
+        return DEFAULT_GATEWAYS
+
+
+def write_node_json(network, gateway_url):
+    """Create or update node.json with custom network."""
+    if not os.path.exists(NODE_FILENAME):
+        with open(NODE_FILENAME, "w") as fp:
+            json.dump({network: gateway_url}, fp)
+    else:
+        with open(NODE_FILENAME, "r+") as fp:
+            gateways = json.load(fp)
+            gateways[network] = gateway_url
+            fp.seek(0)
+            json.dump(gateways, fp, indent=2)
 
 
 GATEWAYS = get_gateways()

src/nile/core/node.py

@@ -1,25 +1,21 @@
 """Command to start StarkNet local network."""
-import json
 import logging
 import subprocess
 
-from nile.common import NODE_FILENAME
+from nile.common import DEFAULT_GATEWAYS, write_node_json
 
 
 def node(host="127.0.0.1", port=5050, seed=None, lite_mode=False):
     """Start StarkNet local network."""
     try:
         # Save host and port information to be used by other commands
-        file = NODE_FILENAME
         if host == "127.0.0.1":
             network = "localhost"
         else:
             network = host
         gateway_url = f"http://{host}:{port}/"
-        gateway = {network: gateway_url}
-
-        with open(file, "w+") as f:
-            json.dump(gateway, f)
+        if DEFAULT_GATEWAYS.get(network) != gateway_url:
+            write_node_json(network, gateway_url)
 
         command = ["starknet-devnet", "--host", host, "--port", str(port)]
 

tests/test_cli.py

@@ -148,7 +148,7 @@ async def test_node_forwards_args(mock_subprocess):
 )
 async def test_node_runs_gateway(opts, expected):
     # Node life
-    seconds = 15
+    seconds = 20
 
     host = opts.get("--host", "127.0.0.1")
     port = opts.get("--port", "5050")
@@ -177,10 +177,11 @@ async def test_node_runs_gateway(opts, expected):
     assert status == 200
 
     # Assert network and gateway_url is correct in node.json file
-    file = NODE_FILENAME
-    with open(file, "r") as f:
-        gateway = json.load(f)
-    assert gateway.get(network) == expected
+    if expected != "http://127.0.0.1:5050/":
+        file = NODE_FILENAME
+        with open(file, "r") as f:
+            gateway = json.load(f)
+        assert gateway.get(network) == expected
 
 
 @pytest.mark.asyncio

tests/test_common.py

@@ -1,7 +1,17 @@
 """Tests for common library."""
+import json
+
 import pytest
 
-from nile.common import parse_information, prepare_params, stringify
+from nile.common import (
+    DEFAULT_GATEWAYS,
+    NODE_FILENAME,
+    write_node_json,
+    get_gateways,
+    parse_information,
+    prepare_params,
+    stringify,
+)
 
 NETWORK = "goerli"
 ARGS = ["1", "2", "3"]
@@ -12,6 +22,12 @@
 STDOUT_2 = "SDTOUT_2"
 
 
+@pytest.fixture(autouse=True)
+def tmp_working_dir(monkeypatch, tmp_path):
+    monkeypatch.chdir(tmp_path)
+    return tmp_path
+
+
 @pytest.mark.parametrize(
     "args, expected",
     [
@@ -48,3 +64,46 @@ def test_parse_information():
 
     _a, _b = parse_information(target)
     assert _a, _b == (a, b)
+
+
+@pytest.mark.parametrize(
+    "network, url, gateway",
+    [
+        (None, None, {}),
+        ("localhost", "5051", {"localhost": "5051"}),
+        ("host", "port", {"host": "port"}),
+    ],
+)
+def test_get_gateways(network, url, gateway):
+    if network is not None:
+        write_node_json(network, url)
+
+    gateways = get_gateways()
+    expected = {**DEFAULT_GATEWAYS, **gateway}
+    assert gateways == expected
+
+    # Check that node.json gateway returns in the case of duplicate keys
+    if network == "localhost":
+        assert expected["localhost"] != "5050"
+        assert expected["localhost"] == "5051"
+
+
+@pytest.mark.parametrize(
+    "args1, args2, gateways",
+    [
+        (
+            ["NETWORK1", "URL1"],
+            ["NETWORK2", "URL2"],
+            {"NETWORK1": "URL1", "NETWORK2": "URL2"},
+        ),
+    ],
+)
+def test_write_node_json(args1, args2, gateways):
+    # Check that node.json is created and adds keys
+    write_node_json(*args1)
+    write_node_json(*args2)
+
+    with open(NODE_FILENAME, "r") as fp:
+        result = fp.read()
+        expected = json.dumps(gateways, indent=2)
+        assert result == expected