CHANGELOG.md

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

[1.2.0] - unreleased

Breaking changes

• Template field body_html renamed to email_body_html to reflect that only the email notifier consumes it (Telegram, Mattermost, and webhook always ignored it). Migration: in every template, replace body_html: with email_body_html:. This applies to templates defined inline in config.yaml and to any split files under templates.d/. Configs using the old name are rejected at load time with a clear error that lists email_body_html among the expected fields, so valerter --validate will point out every template that needs updating on the first run.

Fixed

• Dotted field access in templates (issue #25) — fields like server.hostname or http.request.method can now be referenced directly in Jinja templates using dotted notation, matching the shape users see in log payloads.
• Empty Telegram message guard (issue #26) — Telegram no longer 400s when a rendered body is empty. The notifier now substitutes a fallback string and records the drop reason, and the template documentation explicitly calls out that body_html (now email_body_html) is email-only so users do not accidentally leave body empty.

1.1.0 - 2026-04-15

Added

• Telegram notifier (issue #22) — native type: telegram notifier using the Bot API sendMessage endpoint. Supports multi-chat delivery (one sequential HTTP call per chat_id), HTML parse_mode by default, 429 Retry-After handling, automatic codepoint-safe truncation at Telegram's 4096 character limit, and a new valerter_alerts_truncated_total Prometheus counter.

Known Limitations

• Templates define a single body field that is shared across all notifiers. If you write a Markdown-flavored body (e.g. **bold**, triple-backtick fences) for Mattermost, Telegram will render those markers literally because it is configured with parse_mode: HTML. Workaround: override body_template on the Telegram notifier with HTML-friendly Jinja, for example body_template: "<b>{{ title|e }}</b>\n<pre>{{ body|e }}</pre>". A proper render-pipeline-per-notifier abstraction is planned for 1.2.

1.0.0 - 2026-04-14

Promote 1.0.0-rc.5 to stable. No functional changes.

Security

• Dependency updates via cargo update to pick up patched versions:
  • aws-lc-sys 0.35.0 → 0.39.1 (GHSA advisories on AWS-LC crypto/x509)
  • quinn-proto 0.11.13 → 0.11.14 (QUIC transport parameter DoS)
  • rustls-webpki 0.103.8 → 0.103.11 (CRL scope check)
  • bytes 1.11.0 → 1.11.1 (BytesMut::reserve integer overflow)

1.0.0-rc.5 - 2026-01-20

Final RC - Hardening and observability improvements before 1.0.0 stable.

Added

• TCP keepalive - Prevents silent connection drops on long-lived VictoriaLogs streams (60s keepalive on reqwest client)
• StreamBuffer size limit - 1MB max line size with valerter_lines_discarded_total{reason=oversized} metric to prevent OOM from malformed input
• Strict config validation - deny_unknown_fields rejects typos, URL format validation for VictoriaLogs and webhook endpoints
• Rust load-generator - High-performance testing tool achieving 100k logs/sec for stress testing
• Comprehensive debug logging - Strategic debug/trace logs across all modules for troubleshooting
• Performance test suite - Load testing scripts and documented results (10k+ logs/sec sustained)

Fixed

• Tracing span propagation - Use instrument() for async-safe span propagation in all notifier functions (engine, queue, mattermost, webhook, email)
• Notification success logging - Promoted from debug to info level for production visibility
• Metrics label cleanup - Removed unused rule_name label from alerts_dropped_total (global metric, not per-rule)
• RUST_LOG support - Now properly respects environment variable for log filtering

Changed

• Documentation overhaul - Rewrote README "Why Valerter" section, updated metrics docs with valerter_email_recipient_errors_total and valerter_notifier_config_errors_total, added performance report

1.0.0-rc.4 - 2026-01-16

Feature freeze - From this release, only bug fixes until 1.0.0 stable. No new features or refactoring.

Added

• Multi-file configuration - Split rules, templates, and notifiers into separate files in .d/ directories (rules.d/, templates.d/, notifiers.d/)
• Collision detection - Explicit errors when duplicate names are found across config files
• Warning for unused mattermost_channel - Warns when mattermost_channel is set but no Mattermost notifier in destinations

Changed

• BREAKING: notify.template required - Each rule must now specify its template explicitly (no more defaults.notify.template fallback)
• BREAKING: notify.destinations required - Each rule must specify at least one destination
• BREAKING: defaults.notify removed - The entire defaults.notify section has been removed
• BREAKING: notifiers section required - At least one notifier must be configured
• BREAKING: templates section required - At least one template must be defined
• BREAKING: MATTERMOST_WEBHOOK env var removed - Use notifiers section instead
• BREAKING: notify.channel renamed - Now notify.mattermost_channel for clarity
• Strict field validation - Unknown fields in notify section now cause parsing errors

Fixed

• Debian package - Creates .d/ directories on install

1.0.0-rc.3 - 2026-01-15

Changed

• Simplified tarball - Contains only binary + config.example.yaml (removed install.sh, uninstall.sh, valerter.service)
• Updated Quick Start - Clear separation between .deb and static binary installation paths

1.0.0-rc.2 - 2026-01-15

Added

• Log timestamp in notifications - Original log timestamp now included in all channels (Mattermost footer, Email template, Webhook payload)
• Configurable timezone - New timestamp_timezone setting for formatted timestamps (default: UTC)
• Cisco switches example - Complete alerting example for BPDU Guard violations in examples/cisco-switches/
• Nginx proxy documentation - Required configuration for streaming endpoints (proxy_buffering off)

Fixed

• VictoriaLogs streaming connection - Use HTTP GET instead of POST for /select/logsql/tail endpoint
• Email Outlook compatibility - Simplified template with better rendering across email clients
• Metric description - valerter_victorialogs_up now correctly documented as connection status

Changed

• Refactored config module - Split monolithic config.rs into focused submodules
• Refactored notify module - Split monolithic notify.rs into focused submodules

1.0.0-rc.1 - 2026-01-14

Added

• Email body template system - HTML email templates with body_html field
• Default email template - Built-in templates/default-email.html.j2
• Fail-fast validation - Startup error if email destination uses template without body_html
• Modular documentation - New docs/ folder with detailed guides (getting-started, configuration, notifiers, metrics, architecture)

Fixed

• Metrics recorder race condition - Resolved startup race in Prometheus recorder initialization

Changed

• BREAKING: color → accent_color - Template field renamed for clarity
• BREAKING: icon removed - Template field no longer supported
• README refactored - Reduced from 445 to ~110 lines, now a showcase with links to docs/
• Pipeline diagram - Mermaid replaced with static SVG (no overlay controls)

1.0.0-beta.1 - 2025-01-14

Added

• valerter_build_info metric - Exposes version label for Prometheus dashboards
• CHANGELOG.md - Document all changes following Keep a Changelog format

Fixed

• Debian package auto-restart - Service now automatically restarts on upgrade if running

Changed

• CI optimization - Skip CI for documentation and asset-only changes (.md, images)

1.0.0-alpha.2 - 2025-01-14

Added

• 6 new Prometheus metrics for self-monitoring:
  • valerter_alerts_passed_total - alerts that passed throttling
  • valerter_rule_panics_total - rule task panics (auto-restarted)
  • valerter_rule_errors_total - fatal rule errors
  • valerter_last_query_timestamp - timestamp of last successful query
  • valerter_victorialogs_up - VictoriaLogs connection status
  • valerter_query_duration_seconds - query latency histogram
• Official logo with SVG/PNG variants (light, dark, inverted, lockup)
• Example Prometheus alerts in README for monitoring valerter itself
• "Why Valerter?" section in README comparing with vmalert

Changed

• Simplified installation: valerter_latest_amd64.deb now available via /releases/latest/download/
• README header with centered logo and badges (License, Rust version)

1.0.0-alpha.1 - 2025-01-12

Added

• Initial alpha release
• Real-time log streaming from VictoriaLogs /tail API
• Multi-channel notifications: Mattermost, Email SMTP, Generic Webhook
• Declarative YAML configuration with regex/JSON parsing
• Intelligent throttling with configurable rate limiting per key
• Prometheus metrics endpoint (/metrics)
• Debian package (.deb) and tarball releases
• systemd service integration