Merge pull request #13 from wherobots/max/app-status

feat: handle upcoming PREPARE* AppStatus states

Author: mpetazzoni

wherobots/db/constants.py

@@ -1,5 +1,5 @@
 from enum import auto
-from strenum import LowercaseStrEnum
+from strenum import LowercaseStrEnum, StrEnum
 
 from .region import Region
 from .runtime import Runtime
@@ -67,3 +67,39 @@ class GeometryRepresentation(LowercaseStrEnum):
     EWKT = auto()
     EWKB = auto()
     GEOJSON = auto()
+
+
+class AppStatus(StrEnum):
+    PENDING = auto()
+    PREPARING = auto()
+    PREPARE_FAILED = auto()
+    REQUESTED = auto()
+    DEPLOYING = auto()
+    DEPLOY_FAILED = auto()
+    DEPLOYED = auto()
+    INITIALIZING = auto()
+    INIT_FAILED = auto()
+    READY = auto()
+    DESTROY_REQUESTED = auto()
+    DESTROYING = auto()
+    DESTROY_FAILED = auto()
+    DESTROYED = auto()
+
+    def is_starting(self):
+        return self in (
+            AppStatus.PENDING,
+            AppStatus.PREPARING,
+            AppStatus.REQUESTED,
+            AppStatus.DEPLOYING,
+            AppStatus.DEPLOYED,
+            AppStatus.INITIALIZING,
+        )
+
+    def is_terminal_state(self):
+        return self in (
+            AppStatus.PREPARE_FAILED,
+            AppStatus.DEPLOY_FAILED,
+            AppStatus.INIT_FAILED,
+            AppStatus.DESTROY_FAILED,
+            AppStatus.DESTROYED,
+        )

wherobots/db/driver.py

@@ -21,9 +21,10 @@
     DEFAULT_SESSION_WAIT_TIMEOUT_SECONDS,
     MAX_MESSAGE_SIZE,
     PROTOCOL_VERSION,
-    ResultsFormat,
+    AppStatus,
     DataCompression,
     GeometryRepresentation,
+    ResultsFormat,
 )
 from .errors import (
     InterfaceError,
@@ -107,11 +108,11 @@ def get_session_uri() -> str:
         r = requests.get(session_id_url, headers=headers)
         r.raise_for_status()
         payload = r.json()
-        status = payload.get("status")
+        status = AppStatus(payload.get("status"))
         logging.info(" ... %s", status)
-        if status in ("REQUESTED", "DEPLOYING", "DEPLOYED", "INITIALIZING"):
+        if status.is_starting():
             raise tenacity.TryAgain("SQL Session is not ready yet")
-        elif status == "READY":
+        elif status == AppStatus.READY:
             return payload["appMeta"]["url"]
         else:
             logging.error("SQL session creation failed: %s; should not retry.", status)
@@ -120,6 +121,7 @@ def get_session_uri() -> str:
     try:
         logging.info("Getting SQL session status from %s ...", session_id_url)
         session_uri = get_session_uri()
+        logging.debug("SQL session URI from app status: %s", session_uri)
     except Exception as e:
         raise InterfaceError("Could not acquire SQL session!", e)