ipinfo Location Check Silently Swallows All Network Errors With No Logging or Fallback Notification

[kunal-10-cloud]

Description

base.py lines 100–105 perform a network call to ipinfo.io to geolocate the user, but catch all OSError exceptions silently:

self._client_details = None
if check_location:
    try:
        self._client_details = ipinfo.getHandler().getDetails()
    except OSError:
        pass  # Complete silence — no logging, no warning

When this call fails, _client_details remains None, which cascades to _get_gcp_region() returning None, causing the GCS URL optimisation (choosing a region-local bucket) to silently fall back to the default. The user receives no indication that the location check failed or that their downloads may be coming from a suboptimal region.

---

Steps to Reproduce

import malariagen_data
 
# In an environment where ipinfo.io is blocked
# (corporate firewall, institutional network, etc.):
ag3 = malariagen_data.Ag3()
 
# No warning, no log message — but data may be downloading from a distant GCS region.
print(ag3._gcp_region)  # None — silently fell back to default

---

Root Cause

The except OSError: pass block discards the exception entirely — no log entry, no user-facing warning, no debug message. The resulting None value for _client_details propagates silently through _get_gcp_region(), meaning the GCS bucket selection optimisation is disabled without the user's knowledge.

The failure mode is indistinguishable from a successful lookup that returned no location data.

---

Why This Is a Problem

1. Performance Impact

Researchers in regions with nearby GCS buckets (e.g., us-central1) may unknowingly download multi-GB datasets from a distant bucket. The latency increase can be dramatic for large genomic data access, with no indication that anything is wrong.

2. Debuggability

When users report slow data access, there is no log entry to indicate the location check failed. Support and debugging become guesswork — there is nothing in the application state or logs to correlate slow downloads with a failed ipinfo.io lookup.

3. Prevalence in Target Environments

Institutional and corporate networks — the environments where many researchers operate — frequently block external lookup services like ipinfo.io. These are precisely the users most likely to be affected, and least likely to understand why performance is degraded.

---

Expected Behavior

A failed location check should:

1. Be logged at DEBUG level so that users running with debug=True can diagnose the issue.
2. Optionally emit a user-facing warning explaining that region-optimal storage selection is unavailable and how to manually specify a region-local URL.
   The fallback behaviour itself is acceptable — the fix is about making the failure visible and diagnosable, not about preventing it.

---

Proposed Fix

Before (current behaviour — base.py, lines 100–105):

self._client_details = None
if check_location:
    try:
        self._client_details = ipinfo.getHandler().getDetails()
    except OSError:
        pass  # Complete silence — no logging, no warning

After (proposed fix):

self._client_details = None
if check_location:
    try:
        self._client_details = ipinfo.getHandler().getDetails()
    except OSError as exc:
        self._log.debug("Location check failed: %s", exc)
        warnings.warn(
            "Could not determine client location via ipinfo.io "
            f"({exc}). Region-optimal GCS bucket selection is unavailable. "
            "You can manually specify a region using the `url` parameter.",
            UserWarning,
            stacklevel=2,
        )

The debug-level log ensures the failure is captured when diagnostic logging is enabled. The UserWarning gives researchers in restricted network environments an actionable message without being intrusive in normal usage.

---

Expected Impact After Resolution

• Failed location checks are logged at DEBUG level, visible when debug=True.
• Users in restricted network environments receive an informative UserWarning explaining the fallback and how to manually specify a region-local URL.
• Support burden is reduced — slow download reports can be immediately correlated with the warning rather than requiring infrastructure-level investigation.
• No change to fallback behaviour; the fix is purely additive and fully backward-compatible.

---

Affected File

File	Lines	Code
base.py	100–105	except OSError: pass

---

Severity

Medium — No crash or data corruption, but causes silent, undiagnosable performance degradation for users on restricted networks, which is a common deployment environment for the target research audience.

[kunal-10-cloud]

Hi @jonbrenas, i have raised a PR(#1312) against this issue, please look at it once whenever you are available
Please let me know if any changes are required