PostHog Debug Bundle

Overview

Collect diagnostic evidence for PostHog support tickets. Gathers SDK versions, API connectivity, feature flag status, event flow verification, and redacted configuration. All secrets are automatically redacted.

Prerequisites

• PostHog SDK installed in project
• Access to environment variables
• curl and jq available

Instructions

Tool discipline

Use Read to inspect the relevant configuration and implementation before proposing changes. Use Grep to locate initialization, capture, flag, and credential boundaries.

Step 1: Run Full Diagnostic Script

#!/bin/bash
set -euo pipefail

BUNDLE_DIR="posthog-debug-$(date +%Y%m%d-%H%M%S)"
mkdir -p "$BUNDLE_DIR"

echo "=== PostHog Debug Bundle ===" > "$BUNDLE_DIR/summary.txt"
echo "Generated: $(date -u +%Y-%m-%dT%H:%M:%SZ)" >> "$BUNDLE_DIR/summary.txt"
echo "" >> "$BUNDLE_DIR/summary.txt"

# --- Environment ---
echo "--- Runtime Environment ---" >> "$BUNDLE_DIR/summary.txt"
echo "Node: $(node --version 2>/dev/null || echo 'not found')" >> "$BUNDLE_DIR/summary.txt"
echo "npm: $(npm --version 2>/dev/null || echo 'not found')" >> "$BUNDLE_DIR/summary.txt"
echo "Python: $(python3 --version 2>/dev/null || echo 'not found')" >> "$BUNDLE_DIR/summary.txt"
echo "OS: $(uname -srm)" >> "$BUNDLE_DIR/summary.txt"
echo "" >> "$BUNDLE_DIR/summary.txt"

# --- SDK Versions ---
echo "--- PostHog SDK Versions ---" >> "$BUNDLE_DIR/summary.txt"
npm list posthog-js posthog-node 2>/dev/null >> "$BUNDLE_DIR/summary.txt" || echo "No npm PostHog packages" >> "$BUNDLE_DIR/summary.txt"
pip3 show posthog 2>/dev/null | grep -E "Name|Version" >> "$BUNDLE_DIR/summary.txt" || true
echo "" >> "$BUNDLE_DIR/summary.txt"

# --- API Connectivity ---
echo "--- API Connectivity ---" >> "$BUNDLE_DIR/summary.txt"
echo -n "US Cloud ingest: " >> "$BUNDLE_DIR/summary.txt"
curl -s -o /dev/null -w "%{http_code} (%{time_total}s)" https://us.i.posthog.com/healthz >> "$BUNDLE_DIR/summary.txt" 2>&1
echo "" >> "$BUNDLE_DIR/summary.txt"
echo -n "EU Cloud ingest: " >> "$BUNDLE_DIR/summary.txt"
curl -s -o /dev/null -w "%{http_code} (%{time_total}s)" https://eu.i.posthog.com/healthz >> "$BUNDLE_DIR/summary.txt" 2>&1
echo "" >> "$BUNDLE_DIR/summary.txt"
echo -n "App API: " >> "$BUNDLE_DIR/summary.txt"
curl -s -o /dev/null -w "%{http_code} (%{time_total}s)" https://us.posthog.com/api/ >> "$BUNDLE_DIR/summary.txt" 2>&1
echo "" >> "$BUNDLE_DIR/summary.txt"

# --- Environment Variables (redacted) ---
echo "" >> "$BUNDLE_DIR/summary.txt"
echo "--- Environment Variables (redacted) ---" >> "$BUNDLE_DIR/summary.txt"
env | grep -i posthog | sed 's/=.*/=***REDACTED***/' >> "$BUNDLE_DIR/summary.txt" 2>/dev/null || echo "No POSTHOG env vars found" >> "$BUNDLE_DIR/summary.txt"
echo "" >> "$BUNDLE_DIR/summary.txt"

# --- Key Type Detection ---
echo "--- API Key Types ---" >> "$BUNDLE_DIR/summary.txt"
if [ -n "${NEXT_PUBLIC_POSTHOG_KEY:-}" ]; then
  echo "Project key prefix: $(echo "$NEXT_PUBLIC_POSTHOG_KEY" | head -c 4)_..." >> "$BUNDLE_DIR/summary.txt"
fi
if [ -n "${POSTHOG_PERSONAL_API_KEY:-}" ]; then
  echo "Personal key prefix: $(echo "$POSTHOG_PERSONAL_API_KEY" | head -c 4)_..." >> "$BUNDLE_DIR/summary.txt"
fi

echo "" >> "$BUNDLE_DIR/summary.txt"
echo "Bundle complete: $BUNDLE_DIR/" >> "$BUNDLE_DIR/summary.txt"

Step 2: Test Event Capture Flow Only When Approved

set -euo pipefail
: "${POSTHOG_WRITE_PROBE_APPROVED:?Set only after the incident commander approves a synthetic write}"
test "$POSTHOG_WRITE_PROBE_APPROVED" = "yes"
: "${POSTHOG_PUBLIC_HOST:?Set the regional ingestion host for this project}"

# Send a named synthetic event and verify receipt. A 200 does not prove ingestion.
RESPONSE=$(curl -s -w "\n%{http_code}" -X POST "$POSTHOG_PUBLIC_HOST/i/v0/e/" \
  -H 'Content-Type: application/json' \
  -d "{
    \"api_key\": \"${NEXT_PUBLIC_POSTHOG_KEY}\",
    \"event\": \"debug_bundle_test\",
    \"distinct_id\": \"debug-$(date +%s)\",
    \"properties\": {\"test\": true}
  }")

HTTP_CODE=$(echo "$RESPONSE" | tail -1)
BODY=$(echo "$RESPONSE" | head -1)

echo "Capture test: HTTP $HTTP_CODE"
echo "Response: $BODY"

# Inspect the response for quota_limited and verify the named event plus ingestion warnings.

Step 3: Check Feature Flag Status

set -euo pipefail
# Evaluate flags via the current public endpoint.
curl -s -X POST "$POSTHOG_PUBLIC_HOST/flags?v=2" \
  -H 'Content-Type: application/json' \
  -d "{
    \"api_key\": \"${NEXT_PUBLIC_POSTHOG_KEY}\",
    \"distinct_id\": \"debug-test\"
  }" | jq '{
    flags: .flags,
    errorsParsingFlags: .errorsParsingFlags
  }'

Step 4: Verify Admin API Access

set -euo pipefail
# Test personal API key (if available)
if [ -n "${POSTHOG_PERSONAL_API_KEY:-}" ]; then
  curl -s "https://us.posthog.com/api/projects/" \
    -H "Authorization: Bearer $POSTHOG_PERSONAL_API_KEY" | \
    jq '[.[] | {id, name, created_at}]' > "$BUNDLE_DIR/projects.json" 2>/dev/null || \
    echo "Personal API key failed" >> "$BUNDLE_DIR/summary.txt"
fi

Step 5: Package and Review

set -euo pipefail
# Review for any accidentally included secrets
grep -rn "phc_\|phx_\|Bearer " "$BUNDLE_DIR/" | grep -v REDACTED | grep -v "prefix:" && \
  echo "WARNING: Potential secret found — review before sharing" || \
  echo "No secrets detected in bundle"

# Package
tar -czf "$BUNDLE_DIR.tar.gz" "$BUNDLE_DIR"
echo "Bundle created: $BUNDLE_DIR.tar.gz ($(du -h "$BUNDLE_DIR.tar.gz" | cut -f1))"

Checklist

Item	Collected	Purpose
Node/Python versions	Yes	SDK compatibility
PostHog SDK versions	Yes	Version-specific bugs
API connectivity	Yes	Network/firewall issues
Event capture test	Yes	End-to-end verification
Feature flag status	Yes	Flag evaluation issues
Environment vars (redacted)	Yes	Configuration problems
Key type detection	Yes	Wrong key type errors

Error Handling

Issue	Cause	Solution
All connectivity fails	Corporate firewall	Check proxy settings, try VPN
Capture returns non-200	Invalid API key	Verify phc_ key in project settings
/flags fails	Key/host mismatch	Ensure the project token matches the selected host region
Personal API 401	Expired key	Regenerate in Settings > Personal API Keys

Output

• posthog-debug-YYYYMMDD-HHMMSS.tar.gz archive containing:
  • summary.txt — Runtime, SDK versions, connectivity, redacted config
  • projects.json — Project list (if personal key available)
  • Test event capture and flag evaluation results

Examples

For delayed server events, record SDK versions, configured region, sanitized option names, connectivity status, queue lifecycle, and a bounded log excerpt. Before packaging, scan the bundle for project secrets, personal keys, authorization headers, emails, and event payloads.

Resources

See official PostHog references for current authority and verification boundaries.

• PostHog Status Page
• PostHog Support
• PostHog API Overview

Next Steps

For rate limit issues, see posthog-rate-limits.