rebuild docker image

2026-01-13 13:43:59 -06:00 · 2026-01-13 13:43:59 -06:00 · 1f9bdd57cf
commit 1f9bdd57cf
parent 953d044c9b
10 changed files with 780 additions and 11 deletions
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@ -1,5 +1,5 @@
 # GitLab CI/CD Configuration for Towerops Agent
-# Builds and publishes Docker image to GitLab Container Registry
+# Builds and publishes Docker image to Docker Hub

 stages:
  - test
@ -7,9 +7,9 @@ stages:
  - release

 variables:
-  # GitLab Container Registry
-  REGISTRY: registry.gitlab.com
-  IMAGE_NAME: towerops/towerops-agent
+  # Docker Hub Registry
+  REGISTRY: docker.io
+  IMAGE_NAME: gmcintire/towerops-agent
  # Docker BuildKit for better caching
  DOCKER_BUILDKIT: 1
  DOCKER_TLS_CERTDIR: "/certs"
@ -17,6 +17,8 @@ variables:
 # Test stage - compile and check code
 test:
  stage: test
+  tags:
+    - vntx
  image: rust:1.83-alpine
  before_script:
    - apk add --no-cache musl-dev
@ -37,11 +39,13 @@ test:
 # Build Docker image for branches (test build)
 build:test:
  stage: build
+  tags:
+    - vntx
  image: docker:24-dind
  services:
    - docker:24-dind
  before_script:
-    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
+    - docker login -u $DOCKERHUB_USERNAME -p $DOCKERHUB_TOKEN
  script:
    - |
      docker build \
@ -59,11 +63,13 @@ build:test:
 # Build and push for main branch
 build:main:
  stage: build
+  tags:
+    - vntx
  image: docker:24-dind
  services:
    - docker:24-dind
  before_script:
-    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
+    - docker login -u $DOCKERHUB_USERNAME -p $DOCKERHUB_TOKEN
  script:
    - |
      docker build \
@ -82,11 +88,13 @@ build:main:
 # Release build for tags (versioned releases)
 release:
  stage: release
+  tags:
+    - vntx
  image: docker:24-dind
  services:
    - docker:24-dind
  before_script:
-    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
+    - docker login -u $DOCKERHUB_USERNAME -p $DOCKERHUB_TOKEN
  script:
    - |
      # Extract version from tag (assumes tags like v0.1.0)
@ -114,11 +122,13 @@ release:

 build:multiarch:
  stage: build
+  tags:
+    - vntx
  image: docker:24-dind
  services:
    - docker:24-dind
  before_script:
-    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
+    - docker login -u $DOCKERHUB_USERNAME -p $DOCKERHUB_TOKEN
    # Enable buildx for multi-arch
    - docker buildx create --use --name multiarch-builder
    - docker buildx inspect --bootstrap
--- a/CLAUDE.md
+++ b/CLAUDE.md
@ -0,0 +1,390 @@
+# Towerops Agent - Development Notes
+
+This file provides context for Claude Code when working on the Rust agent.
+
+## Project Overview
+
+Lightweight Rust agent for remote SNMP polling. Deployed on customer networks to poll local SNMP devices and report metrics to Towerops API via HTTPS.
+
+## What's Complete ✅
+
+### Architecture & Design
+- [x] Complete module structure (12 source files)
+- [x] Configuration types matching Phoenix API responses
+- [x] Metric types (SensorReading, InterfaceStat) with proper serialization
+- [x] Event loop with 5 concurrent tasks (tokio::select!)
+- [x] SQLite buffering with 24-hour retention
+- [x] Error types and result handling throughout
+
+### Core Functionality
+- [x] **API Client** (`api_client.rs`)
+  - fetch_config() - GET /api/v1/agent/config
+  - submit_metrics() - POST /api/v1/agent/metrics
+  - heartbeat() - POST /api/v1/agent/heartbeat
+  - Uses reqwest with rustls-tls (30s timeout)
+
+- [x] **Storage** (`buffer/storage.rs`)
+  - store_metric() - Save metrics to SQLite
+  - get_pending_metrics() - Retrieve unsent metrics
+  - mark_metrics_sent() - Track submission
+  - cleanup_old_metrics() - Remove old data
+  - Last poll time tracking per equipment
+
+- [x] **Scheduler** (`poller/scheduler.rs`)
+  - Config refresh every 5 minutes
+  - Metrics flush every 30 seconds
+  - Heartbeat every 60 seconds
+  - Cleanup every hour
+  - Poll check every 5 seconds
+
+- [x] **Executor** (`poller/executor.rs`)
+  - poll_sensors() - Poll configured sensors
+  - poll_interfaces() - Poll interface statistics
+  - Parallel polling with tokio::join!
+  - Applies sensor divisors
+
+- [x] **Main** (`main.rs`)
+  - CLI with clap (--api-url, --token, etc.)
+  - Environment variable support
+  - Logging with tracing
+  - Graceful startup/shutdown
+
+### Build & Deployment
+- [x] Cargo.toml with optimized release profile
+  - opt-level = "z"
+  - lto = true
+  - codegen-units = 1
+  - strip = true
+- [x] Multi-stage Dockerfile (Alpine, ~10-20 MB)
+- [x] docker-compose.example.yml
+- [x] README with user documentation
+- [x] .gitignore and .dockerignore
+
+### Build Status
+```bash
+✅ cargo build --release - SUCCESS
+⚠️  5 warnings (unused code - expected)
+📦 Target size optimized for minimal footprint
+```
+
+## What's Incomplete 🔄
+
+### CRITICAL: SNMP Library Integration
+
+**Location**: `src/snmp/client.rs`
+
+**Problem**: The `snmp` crate v0.2 API is different than initially designed. Current implementation:
+- Validates IP addresses
+- Returns error for actual SNMP operations
+- Compiles successfully but doesn't poll
+
+**Current Code**:
+```rust
+pub async fn get(...) -> SnmpResult<SnmpValue> {
+    // Validates IP
+    // Returns: "SNMP implementation incomplete"
+}
+
+pub async fn walk(...) -> SnmpResult<Vec<(String, SnmpValue)>> {
+    // Validates IP
+    // Returns: empty vec
+}
+```
+
+**What's Needed**:
+
+1. Research the correct `snmp` crate 0.2 API:
+```bash
+cargo doc --open --package snmp
+```
+
+2. Implement actual SNMP operations:
+   - Create session with proper parameters
+   - Perform GET request for single OID
+   - Perform GETNEXT/WALK for OID subtrees
+   - Handle response parsing
+   - Map errors (timeout, auth failure, etc.)
+
+3. Key questions to answer:
+   - How to create SyncSession? (signature changed)
+   - How to send GET request? (method name/signature)
+   - How to send GETNEXT? (for walk implementation)
+   - How to parse responses? (varbinds format)
+   - How to handle errors? (error enum changed)
+
+4. Reference implementation:
+   - Check `snmp` crate examples directory
+   - Look at crate tests for usage patterns
+   - May need to read source code directly
+
+**Alternatives if `snmp` v0.2 doesn't work**:
+- `snmp-mp` crate (more actively maintained)
+- `snmp-parser` crate (lower level, more control)
+- `rasn-snmp` crate (ASN.1 based)
+
+**Estimated Effort**: 4-8 hours
+
+### Testing Gaps
+
+- [ ] Unit tests for SNMP client (depends on SNMP integration)
+- [ ] Unit tests for storage (SQLite operations)
+- [ ] Unit tests for API client (mock server)
+- [ ] Integration test with real SNMP device
+
+## Development Workflow
+
+### Quick Start
+
+1. **Build the agent**:
+```bash
+cargo build --release
+```
+
+2. **Run locally** (needs Phoenix backend running):
+```bash
+cargo run -- \
+  --api-url http://localhost:4000 \
+  --token <get-from-ui> \
+  --database-path ./test.db
+```
+
+3. **Watch logs**:
+```bash
+RUST_LOG=debug cargo run -- ...
+```
+
+### Testing Changes
+
+1. **Check compilation**:
+```bash
+cargo check
+```
+
+2. **Run tests**:
+```bash
+cargo test
+```
+
+3. **Format code**:
+```bash
+cargo fmt
+```
+
+4. **Check for issues**:
+```bash
+cargo clippy
+```
+
+### Docker Testing
+
+1. **Build image**:
+```bash
+docker build -t towerops-agent:test .
+```
+
+2. **Run container**:
+```bash
+docker run --rm \
+  -e TOWEROPS_API_URL=http://host.docker.internal:4000 \
+  -e TOWEROPS_AGENT_TOKEN=<token> \
+  -e RUST_LOG=info \
+  -v $(pwd)/data:/data \
+  towerops-agent:test
+```
+
+### CI/CD Pipeline
+
+**Automated builds** via GitLab CI (`.gitlab-ci.yml`):
+- Push to branch → test + build with branch tag
+- Push to main → test + build + tag as `latest`
+- Create tag (e.g., `v0.1.0`) → test + build + release
+
+**Registry**: `registry.gitlab.com/towerops/towerops-agent`
+
+**See**: `DEPLOYMENT.md` for complete CI/CD documentation
+
+## Integration with Phoenix Backend
+
+### API Endpoints (from agent perspective)
+
+**GET /api/v1/agent/config**
+- Headers: `Authorization: Bearer <token>`
+- Response: Equipment list with sensors and interfaces
+- Called every 5 minutes
+
+**POST /api/v1/agent/metrics**
+- Headers: `Authorization: Bearer <token>`
+- Body: `{"metrics": [...]}`
+- Response: `{"status": "accepted", "received": N}`
+- Called every 30 seconds with pending metrics
+
+**POST /api/v1/agent/heartbeat**
+- Headers: `Authorization: Bearer <token>`
+- Body: `{"version": "0.1.0", "hostname": "...", "uptime_seconds": 3600}`
+- Response: `{"status": "ok"}`
+- Called every 60 seconds
+
+### Getting a Test Token
+
+1. Start Phoenix: `mix phx.server`
+2. Navigate to: `http://localhost:4000/orgs/:slug/agents`
+3. Click "Create New Agent"
+4. Copy the token (shown only once)
+5. Use in agent: `--token <copied-token>`
+
+## Architecture Decisions
+
+### Why Tokio?
+- Async event loop for efficient I/O
+- Multiple concurrent timers (config, metrics, heartbeat)
+- Non-blocking SNMP operations via spawn_blocking
+
+### Why SQLite?
+- Embedded, no external dependencies
+- Persist metrics during API outages
+- Small footprint (~100 MB for 24h of metrics)
+- No configuration needed
+
+### Why Rust?
+- Small binary size (~10-20 MB with Alpine)
+- Low memory usage (<256 MB typical)
+- Cross-compile to multiple architectures
+- Strong type safety for reliability
+
+### Why Simplified SNMP?
+- The `snmp` crate v0.2 API required research
+- Chose to ship architecture first, SNMP second
+- Allows testing of everything except SNMP polling
+- Can be completed independently
+
+## Common Issues
+
+### "SNMP implementation incomplete" Error
+**Expected**: This is the TODO for SNMP integration. The agent runs but can't poll devices yet.
+
+### "Failed to fetch config" Error
+**Check**:
+1. Is Phoenix backend running?
+2. Is the token valid (not revoked)?
+3. Is the API URL correct?
+4. Is there network connectivity?
+
+### High Memory Usage
+**Check**:
+1. Database size: `ls -lh /data/towerops-agent.db`
+2. Are metrics being submitted? (check logs)
+3. Is cleanup running? (should see log every hour)
+
+### Agent Not Showing as Online
+**Check**:
+1. Is heartbeat working? (check Phoenix logs)
+2. Check `last_seen_at` in database: `SELECT last_seen_at FROM agent_tokens WHERE token_hash = ...`
+3. Time sync between agent and server
+
+## File Organization
+
+```
+towerops-agent/
+├── src/
+│   ├── main.rs              # Entry point, CLI, initialization
+│   ├── config.rs            # Types matching API responses
+│   ├── api_client.rs        # HTTP client for Towerops API
+│   ├── metrics/
+│   │   └── mod.rs          # Metric types (SensorReading, InterfaceStat)
+│   ├── snmp/
+│   │   ├── mod.rs          # Module exports
+│   │   ├── client.rs       # ⚠️ INCOMPLETE - needs SNMP integration
+│   │   └── types.rs        # SNMP types and errors
+│   ├── buffer/
+│   │   ├── mod.rs          # Module exports
+│   │   └── storage.rs      # SQLite buffering
+│   └── poller/
+│       ├── mod.rs          # Module exports
+│       ├── executor.rs     # Poll execution logic
+│       └── scheduler.rs    # Main event loop
+├── Cargo.toml              # Dependencies and build config
+├── Dockerfile              # Multi-stage build
+├── README.md               # User documentation
+└── CLAUDE.md              # This file
+```
+
+## Dependencies
+
+**Key Crates**:
+- `tokio` - Async runtime with full features
+- `reqwest` - HTTP client (rustls-tls, no default features)
+- `rusqlite` - SQLite (bundled)
+- `serde` + `serde_json` - Serialization
+- `snmp` - SNMP operations (v0.2) ⚠️ needs integration
+- `tracing` + `tracing-subscriber` - Logging
+- `clap` - CLI argument parsing
+- `chrono` - Timestamps
+- `anyhow` + `thiserror` - Error handling
+- `hostname` - Get system hostname
+
+## Next Actions
+
+**Immediate** (to make agent functional):
+1. Research `snmp` crate v0.2 API documentation
+2. Update `src/snmp/client.rs` with working implementation
+3. Test with a real SNMP device or simulator
+4. Add unit tests for SNMP operations
+
+**Short-term** (for production readiness):
+1. Add more comprehensive unit tests
+2. Integration test with mock SNMP device
+3. Load test with 100 devices
+4. Stability test (7+ days continuous)
+
+**Long-term** (nice to have):
+1. SNMPv3 support
+2. Agent-side threshold filtering
+3. Configurable sampling rates
+4. Agent health metrics endpoint
+
+## Resources
+
+- **Main Implementation Doc**: `/Users/graham/dev/towerops/AGENT_IMPLEMENTATION.md`
+- **Next Steps Guide**: `/Users/graham/dev/towerops/AGENT_NEXT_STEPS.md`
+- **SNMP Crate Docs**: https://docs.rs/snmp/0.2.2/snmp/
+- **SNMP Crate Source**: https://github.com/hroi/snmp-rs
+
+## Success Criteria
+
+Agent is production-ready when:
+- [x] Compiles successfully
+- [x] Docker image builds
+- [x] API client works (config, metrics, heartbeat)
+- [x] SQLite buffering works
+- [x] Event loop runs without panics
+- [ ] **SNMP polling works** ← ONLY REMAINING ITEM
+- [ ] Metrics appear in Phoenix database
+- [ ] Survives 24h API outage
+- [ ] Uses <256 MB memory with 50 devices
+- [ ] Runs for 7+ days without issues
+
+## Notes for Future Development
+
+### Adding New Metric Types
+1. Add variant to `Metric` enum in `src/metrics/mod.rs`
+2. Update `metric_type()` and `timestamp()` methods
+3. Update Phoenix API to accept new type
+4. Add serialization test
+
+### Adding New Configuration Fields
+1. Update structs in `src/config.rs`
+2. Update Phoenix API `build_equipment_config/1`
+3. Consider backwards compatibility
+
+### Debugging SNMP Issues
+- Set `RUST_LOG=debug` to see all SNMP operations
+- Check IP reachability: `ping <device-ip>`
+- Test SNMP manually: `snmpget -v2c -c public <device-ip> <oid>`
+- Verify community string is correct
+- Check firewall rules (UDP port 161)
+
+---
+
+**Last Updated**: January 9, 2026
+**Status**: Architecture complete, SNMP integration pending
+**Version**: 0.1.0 (pre-release)
--- a/Cargo.lock
+++ b/Cargo.lock
@ -73,6 +73,12 @@ dependencies = [
 "windows-sys",
 ]

+[[package]]
+name = "anyhow"
+version = "1.0.100"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a23eb6b1614318a8071c9b2521f36b424b2c83db5eb3a0fead4a6c0809af6e61"
+
 [[package]]
 name = "base64"
 version = "0.22.1"
@ -85,6 +91,12 @@ version = "2.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "812e12b5285cc515a9c72a5c1d3b6d46a19dac5acfef5265968c166106e31dd3"

+[[package]]
+name = "bytes"
+version = "1.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b35204fbdc0b3f4446b89fc1ac2cf84a8a68971995d0bf2e925ec7cd960f9cb3"
+
 [[package]]
 name = "cc"
 version = "1.2.52"
@ -158,6 +170,12 @@ dependencies = [
 "syn",
 ]

+[[package]]
+name = "either"
+version = "1.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "48c757948c5ede0e46177b7add2e67155f70e33c07fea8284df6576da70b3719"
+
 [[package]]
 name = "env_filter"
 version = "0.1.4"
@ -181,6 +199,22 @@ dependencies = [
 "log",
 ]

+[[package]]
+name = "equivalent"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
+
+[[package]]
+name = "errno"
+version = "0.3.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "39cab71617ae0d63f51a36d69f866391735b51691dbda63cf6f96d042b63efeb"
+dependencies = [
+ "libc",
+ "windows-sys",
+]
+
 [[package]]
 name = "fallible-iterator"
 version = "0.3.0"
@ -193,12 +227,24 @@ version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7360491ce676a36bf9bb3c56c1aa791658183a54d2744120f27285738d90465a"

+[[package]]
+name = "fastrand"
+version = "2.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "37909eebbb50d72f9059c3b6d82c0463f2ff062c9e95845c43a6c9c0355411be"
+
 [[package]]
 name = "find-msvc-tools"
 version = "0.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f449e6c6c08c865631d4890cfacf252b3d396c9bcc83adb6623cdb02a8336c41"

+[[package]]
+name = "fixedbitset"
+version = "0.5.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d674e81391d1e1ab681a28d99df07927c6d4aa5b027d7da16ba32d1d21ecd99"
+
 [[package]]
 name = "form_urlencoded"
 version = "1.2.2"
@ -208,6 +254,18 @@ dependencies = [
 "percent-encoding",
 ]

+[[package]]
+name = "getrandom"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "899def5c37c4fd7b2664648c28120ecec138e4d395b459e5ca34f9cce2dd77fd"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "r-efi",
+ "wasip2",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.14.5"
@ -217,13 +275,19 @@ dependencies = [
 "ahash",
 ]

+[[package]]
+name = "hashbrown"
+version = "0.16.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "841d1cc9bed7f9236f321df977030373f4a4163ae1a7dbfe1a51a2c1a51d9100"
+
 [[package]]
 name = "hashlink"
 version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ba4ff7128dee98c7dc9794b6a411377e1404dba1c97deb8d1a55297bd25d8af"
 dependencies = [
- "hashbrown",
+ "hashbrown 0.14.5",
 ]

 [[package]]
@ -345,12 +409,31 @@ dependencies = [
 "icu_properties",
 ]

+[[package]]
+name = "indexmap"
+version = "2.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7714e70437a7dc3ac8eb7e6f8df75fd8eb422675fc7678aff7364301092b1017"
+dependencies = [
+ "equivalent",
+ "hashbrown 0.16.1",
+]
+
 [[package]]
 name = "is_terminal_polyfill"
 version = "1.70.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a6cb138bb79a146c1bd460005623e142ef0181e3d0219cb493e02f7d08a35695"

+[[package]]
+name = "itertools"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b192c782037fadd9cfa75548310488aabdbf3d2da73885b31bd0abd03351285"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "itoa"
 version = "1.0.17"
@ -398,6 +481,12 @@ dependencies = [
 "vcpkg",
 ]

+[[package]]
+name = "linux-raw-sys"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "df1d3c3b53da64cf5760482273a98e575c651a67eec7f77df96b5b642de8f039"
+
 [[package]]
 name = "litemap"
 version = "0.8.1"
@ -416,6 +505,12 @@ version = "2.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f52b00d39961fc5b2736ea853c9cc86238e165017a493d1d5c8eac6bdc4cc273"

+[[package]]
+name = "multimap"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d87ecb2933e8aeadb3e3a02b828fed80a7528047e68b4f424523a0981a3a084"
+
 [[package]]
 name = "once_cell"
 version = "1.21.3"
@ -434,6 +529,16 @@ version = "2.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b4f627cb1b25917193a259e49bdad08f671f8d9708acfd5fe0a8c1455d87220"

+[[package]]
+name = "petgraph"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3672b37090dbd86368a4145bc067582552b29c27377cad4e0a306c97f9bd7772"
+dependencies = [
+ "fixedbitset",
+ "indexmap",
+]
+
 [[package]]
 name = "pin-project-lite"
 version = "0.2.16"
@ -470,6 +575,16 @@ dependencies = [
 "zerovec",
 ]

+[[package]]
+name = "prettyplease"
+version = "0.2.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "479ca8adacdd7ce8f1fb39ce9ecccbfe93a3f1344b3d0d97f20bc0196208f62b"
+dependencies = [
+ "proc-macro2",
+ "syn",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.105"
@ -479,6 +594,58 @@ dependencies = [
 "unicode-ident",
 ]

+[[package]]
+name = "prost"
+version = "0.13.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2796faa41db3ec313a31f7624d9286acf277b52de526150b7e69f3debf891ee5"
+dependencies = [
+ "bytes",
+ "prost-derive",
+]
+
+[[package]]
+name = "prost-build"
+version = "0.13.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "be769465445e8c1474e9c5dac2018218498557af32d9ed057325ec9a41ae81bf"
+dependencies = [
+ "heck",
+ "itertools",
+ "log",
+ "multimap",
+ "once_cell",
+ "petgraph",
+ "prettyplease",
+ "prost",
+ "prost-types",
+ "regex",
+ "syn",
+ "tempfile",
+]
+
+[[package]]
+name = "prost-derive"
+version = "0.13.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a56d757972c98b346a9b766e3f02746cde6dd1cd1d1d563472929fdd74bec4d"
+dependencies = [
+ "anyhow",
+ "itertools",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "prost-types"
+version = "0.13.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "52c2c1bf36ddb1a1c396b3601a3cec27c2462e45f07c386894ec3ccf5332bd16"
+dependencies = [
+ "prost",
+]
+
 [[package]]
 name = "quote"
 version = "1.0.43"
@ -488,6 +655,12 @@ dependencies = [
 "proc-macro2",
 ]

+[[package]]
+name = "r-efi"
+version = "5.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69cdb34c158ceb288df11e18b4bd39de994f6657d83847bdffdbd7f346754b0f"
+
 [[package]]
 name = "regex"
 version = "1.12.2"
@ -531,6 +704,19 @@ dependencies = [
 "smallvec",
 ]

+[[package]]
+name = "rustix"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "146c9e247ccc180c1f61615433868c99f3de3ae256a30a43b49f67c2d9171f34"
+dependencies = [
+ "bitflags",
+ "errno",
+ "libc",
+ "linux-raw-sys",
+ "windows-sys",
+]
+
 [[package]]
 name = "serde"
 version = "1.0.228"
@ -626,6 +812,19 @@ dependencies = [
 "syn",
 ]

+[[package]]
+name = "tempfile"
+version = "3.24.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "655da9c7eb6305c55742045d5a8d2037996d61d8de95806335c7c86ce0f82e9c"
+dependencies = [
+ "fastrand",
+ "getrandom",
+ "once_cell",
+ "rustix",
+ "windows-sys",
+]
+
 [[package]]
 name = "thiserror"
 version = "1.0.69"
@ -685,6 +884,9 @@ dependencies = [
 "env_logger",
 "hostname",
 "log",
+ "prost",
+ "prost-build",
+ "prost-types",
 "rusqlite",
 "serde",
 "serde_json",
@ -750,6 +952,15 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"

+[[package]]
+name = "wasip2"
+version = "1.0.1+wasi-0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0562428422c63773dad2c345a1882263bbf4d65cf3f42e90921f787ef5ad58e7"
+dependencies = [
+ "wit-bindgen",
+]
+
 [[package]]
 name = "windows-link"
 version = "0.2.1"
@ -765,6 +976,12 @@ dependencies = [
 "windows-link",
 ]

+[[package]]
+name = "wit-bindgen"
+version = "0.46.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f17a85883d4e6d00e8a97c586de764dabcc06133f7f1d55dce5cdc070ad7fe59"
+
 [[package]]
 name = "writeable"
 version = "0.6.2"
--- a/Cargo.toml
+++ b/Cargo.toml
@ -15,6 +15,11 @@ env_logger = "0.11"
 thiserror = "1.0"
 clap = { version = "4.0", features = ["derive", "env"] }
 hostname = "0.4"
+prost = "0.13"
+prost-types = "0.13"
+
+[build-dependencies]
+prost-build = "0.13"

 [profile.release]
 opt-level = "z"
--- a/build.rs
+++ b/build.rs
@ -0,0 +1,3 @@
+fn main() {
+    prost_build::compile_protos(&["proto/agent.proto"], &["proto/"]).unwrap();
+}
--- a/proto/agent.proto
+++ b/proto/agent.proto
@ -0,0 +1,83 @@
+syntax = "proto3";
+
+package towerops.agent;
+
+// Configuration received from the API
+message AgentConfig {
+  string version = 1;
+  uint32 poll_interval_seconds = 2;
+  repeated Equipment equipment = 3;
+}
+
+message Equipment {
+  string id = 1;
+  string name = 2;
+  string ip_address = 3;
+  SnmpConfig snmp = 4;
+  uint32 poll_interval_seconds = 5;
+  repeated Sensor sensors = 6;
+  repeated Interface interfaces = 7;
+}
+
+message SnmpConfig {
+  bool enabled = 1;
+  string version = 2;
+  string community = 3;
+  uint32 port = 4;
+}
+
+message Sensor {
+  string id = 1;
+  string type = 2;
+  string oid = 3;
+  double divisor = 4;
+  string unit = 5;
+  map<string, string> metadata = 6;
+}
+
+message Interface {
+  string id = 1;
+  uint32 if_index = 2;
+  string if_name = 3;
+}
+
+// Metrics submitted to the API
+message MetricBatch {
+  repeated Metric metrics = 1;
+}
+
+message Metric {
+  oneof metric_type {
+    SensorReading sensor_reading = 1;
+    InterfaceStat interface_stat = 2;
+  }
+}
+
+message SensorReading {
+  string sensor_id = 1;
+  double value = 2;
+  string status = 3;
+  int64 timestamp = 4; // Unix timestamp in seconds
+}
+
+message InterfaceStat {
+  string interface_id = 1;
+  int64 if_in_octets = 2;
+  int64 if_out_octets = 3;
+  int64 if_in_errors = 4;
+  int64 if_out_errors = 5;
+  int64 if_in_discards = 6;
+  int64 if_out_discards = 7;
+  int64 timestamp = 8; // Unix timestamp in seconds
+}
+
+// Heartbeat metadata
+message HeartbeatMetadata {
+  string version = 1;
+  string hostname = 2;
+  uint64 uptime_seconds = 3;
+}
+
+message HeartbeatResponse {
+  string status = 1;
+}
--- a/src/api_client.rs
+++ b/src/api_client.rs
@ -1,5 +1,7 @@
 use crate::config::{AgentConfig, HeartbeatMetadata};
 use crate::metrics::Metric;
+use crate::proto::agent;
+use prost::Message;
 use serde_json::json;
 use std::time::Duration;
 use thiserror::Error;
@ -63,7 +65,7 @@ impl ApiClient {
        Ok(config)
    }

-    /// Submit metrics to the API
+    /// Submit metrics to the API using Protocol Buffers
    pub async fn submit_metrics(&self, metrics: Vec<Metric>) -> Result<()> {
        if metrics.is_empty() {
            return Ok(());
@ -73,10 +75,28 @@ impl ApiClient {
        let token = self.token.clone();

        tokio::task::spawn_blocking(move || {
+            // Convert metrics to protobuf
+            let proto_metrics: Vec<agent::Metric> = metrics
+                .into_iter()
+                .map(|m| convert_metric_to_proto(&m))
+                .collect();
+
+            let batch = agent::MetricBatch {
+                metrics: proto_metrics,
+            };
+
+            // Encode to bytes
+            let mut buf = Vec::new();
+            batch
+                .encode(&mut buf)
+                .map_err(|e| ApiError::RequestFailed(format!("Protobuf encoding error: {}", e)))?;
+
+            // Send as protobuf
            let response = ureq::post(&url)
                .set("Authorization", &format!("Bearer {}", token))
+                .set("Content-Type", "application/x-protobuf")
                .timeout(Duration::from_secs(30))
-                .send_json(json!({ "metrics": metrics }))
+                .send_bytes(&buf)
                .map_err(|e| ApiError::RequestFailed(e.to_string()))?;

            let status = response.status();
@ -117,3 +137,35 @@ impl ApiClient {
        Ok(())
    }
 }
+
+/// Convert internal Metric type to protobuf Metric
+fn convert_metric_to_proto(metric: &Metric) -> agent::Metric {
+    use crate::metrics::Metric as M;
+
+    match metric {
+        M::SensorReading(sr) => agent::Metric {
+            metric_type: Some(agent::metric::MetricType::SensorReading(
+                agent::SensorReading {
+                    sensor_id: sr.sensor_id.clone(),
+                    value: sr.value,
+                    status: sr.status.clone(),
+                    timestamp: sr.timestamp.to_unix_timestamp(),
+                },
+            )),
+        },
+        M::InterfaceStat(is) => agent::Metric {
+            metric_type: Some(agent::metric::MetricType::InterfaceStat(
+                agent::InterfaceStat {
+                    interface_id: is.interface_id.clone(),
+                    if_in_octets: is.if_in_octets,
+                    if_out_octets: is.if_out_octets,
+                    if_in_errors: is.if_in_errors,
+                    if_out_errors: is.if_out_errors,
+                    if_in_discards: is.if_in_discards,
+                    if_out_discards: is.if_out_discards,
+                    timestamp: is.timestamp.to_unix_timestamp(),
+                },
+            )),
+        },
+    }
+}
--- a/src/main.rs
+++ b/src/main.rs
@ -3,6 +3,7 @@ mod buffer;
 mod config;
 mod metrics;
 mod poller;
+mod proto;
 mod snmp;

 use clap::Parser;
--- a/src/metrics/mod.rs
+++ b/src/metrics/mod.rs
@ -21,6 +21,10 @@ impl Timestamp {
        Self::now().secs - self.secs
    }

+    pub fn to_unix_timestamp(&self) -> i64 {
+        self.secs
+    }
+
    pub fn to_rfc3339(self) -> String {
        // Convert Unix timestamp to RFC3339 format
        // This is a simplified implementation that produces UTC timestamps
--- a/src/proto.rs
+++ b/src/proto.rs
@ -0,0 +1,4 @@
+// Generated protobuf code
+pub mod agent {
+    include!(concat!(env!("OUT_DIR"), "/towerops.agent.rs"));
+}