feat: reuse available session by default

Author: mpetazzoni

README.md

@@ -81,3 +81,6 @@ users may find useful:
     client application. The default is EWKT (string) and the most
     convenient for human inspection while still being usable by
     libraries like Shapely.
+* `reuse_session`: controls whether an existing runtime of the same type
+    and in the same region that is available should be re-used for this
+    connection. This is the default behavior.

wherobots/db/constants.py

@@ -7,10 +7,13 @@
 
 DEFAULT_ENDPOINT: str = "api.cloud.wherobots.com"  # "api.cloud.wherobots.com"
 STAGING_ENDPOINT: str = "api.staging.wherobots.com"  # "api.staging.wherobots.com"
+
 DEFAULT_RUNTIME: Runtime = Runtime.TINY
 DEFAULT_REGION: Region = Region.AWS_US_WEST_2
 DEFAULT_READ_TIMEOUT_SECONDS: float = 0.25
 DEFAULT_SESSION_WAIT_TIMEOUT_SECONDS: float = 900
+DEFAULT_REUSE_SESSION: bool = True
+
 MAX_MESSAGE_SIZE: int = 100 * 2**20  # 100MiB
 PROTOCOL_VERSION: str = "1.0.0"
 

wherobots/db/driver.py

@@ -19,6 +19,7 @@
 from .constants import (
     DEFAULT_ENDPOINT,
     DEFAULT_REGION,
+    DEFAULT_REUSE_SESSION,
     DEFAULT_RUNTIME,
     DEFAULT_READ_TIMEOUT_SECONDS,
     DEFAULT_SESSION_WAIT_TIMEOUT_SECONDS,
@@ -62,6 +63,7 @@ def connect(
     region: Region = None,
     wait_timeout: float = DEFAULT_SESSION_WAIT_TIMEOUT_SECONDS,
     read_timeout: float = DEFAULT_READ_TIMEOUT_SECONDS,
+    reuse_session: bool = DEFAULT_REUSE_SESSION,
     shutdown_after_inactive_seconds: Union[int, None] = None,
     results_format: Union[ResultsFormat, None] = None,
     data_compression: Union[DataCompression, None] = None,
@@ -83,8 +85,8 @@ def connect(
     region = region or DEFAULT_REGION
 
     logging.info(
-        "Requesting %s/%s runtime in %s from %s ...",
-        runtime.name,
+        "%s %s runtime in %s from %s ...",
+        "Recycling" if reuse_session else "Requesting",
         runtime.value,
         region.value,
         host,
@@ -97,7 +99,7 @@ def connect(
     try:
         resp = requests.post(
             url=f"{host}/sql/session",
-            params={"region": region.value},
+            params={"region": region.value, "reuse_session": reuse_session},
             json={
                 "runtimeId": runtime.value,
                 "shutdownAfterInactiveSeconds": shutdown_after_inactive_seconds,