feat: HTTPClient health check

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "mospy-wallet"
-version = "0.5.3"
+version = "0.5.4"
 description = "This package is a fork of cosmospy and is a light framework for the cosmos ecosystem"
 authors = [
     { name = "ctrl-felix", email = "[email protected]" },

src/mospy/clients/HTTPClient.py

@@ -6,7 +6,7 @@
 from mospy.Transaction import Transaction
 
 from mospy.exceptions.clients import NodeException
-from mospy.exceptions.clients import NodeTimeoutException, TransactionNotFound, TransactionTimeout
+from mospy.exceptions.clients import NodeTimeoutException, TransactionNotFound, TransactionTimeout, NotAnApiNode
 
 
 class HTTPClient:
@@ -15,10 +15,33 @@ class HTTPClient:
 
     Args:
         api (str): URL to a Api node
+        check_api (bool): Check if the Api node is reachable. Returns either NotAnApiNode or NodeException if the node is not healthy.
     """
 
-    def __init__(self, *, api: str = "https://rest.cosmos.directory/cosmoshub"):
-        self._api = api
+    def __init__(self, *, api: str = "https://rest.cosmos.directory/cosmoshub", check_api: bool = False):
+        self._api = api.rstrip("/")
+
+        # Check API if reachable
+        if check_api:
+            self.check_api()
+
+    def check_api(self):
+        """
+        Checks if the API is reachable. Returns a NodeException or a NotAnApiNode Exception when the check failed.
+        """
+        try:
+            check_response = httpx.get(self._api + "/node_info")
+        except httpx.HTTPError:
+            raise NodeException(
+                "The passed url is not reachable. To disable the health check pass check_api=false to the HTTPClient constructor.")
+
+        if check_response.status_code != 200:
+            # Check if the returned text matches the one returned by an RPC
+            if "404 page not found" in check_response.text:
+                raise NotAnApiNode("Please pass an API endpoint to the HTTPClient. You probably passed an RPC.")
+            else:
+                raise NodeException(
+                    "Health couldn't be verified. To disable the health check pass check_api=false to the HTTPClient constructor.")
 
     def _make_post_request(self, path, payload, timeout):
         try:

src/mospy/exceptions/clients.py

@@ -12,4 +12,7 @@ class TransactionTimeout(Exception):
 
 class TransactionNotFound(Exception):
     """Raised when the transaction couldn't be found on chain."""
-    pass
+    pass
+
+class NotAnApiNode(Exception):
+    """The url passed to the constructor couldn't be detected as API node. This might be because you passed the rpc endpoint instead."""

tests/clients/test_httpclient.py

@@ -5,6 +5,8 @@
 from mospy import Transaction
 from mospy.clients import HTTPClient
 
+from mospy.exceptions.clients import NotAnApiNode, NodeException
+
 API = "https://cosmos-rest.publicnode.com"
 
 class TestHTTPClientClass:
@@ -21,6 +23,23 @@ def test_account_data_loading(self):
 
         assert account.next_sequence >= 0
 
+    def test_node_health_check(self):
+        try:
+            client = HTTPClient(api="https://cosmos-rpc.publicnode.com", check_api=True)
+        except NotAnApiNode:
+            assert True
+        else:
+            assert False
+
+        try:
+            client = HTTPClient(api="https://dead-url-awdbnawdbauiowd.com", check_api=True)
+        except NodeException:
+            assert True
+        else:
+            assert False
+
+        client = HTTPClient(api="https://dead-url-awdbnawdbauiowd.com", check_api=False)
+
     def test_transaction_submitting(self):
         account = Account(
             seed_phrase=self.seed_phrase,