tree.fail
PLC Directory over DNS (experiment)
Initial commit
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.gitignore
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.gitignore
···
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# Binaries
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plcdns
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*.exe
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*.dll
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*.so
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*.dylib
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# Test binary
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*.test
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# Output of the go coverage tool
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*.out
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coverage.html
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# Dependency directories
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vendor/
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# Go workspace file
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go.work
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# IDE
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.vscode/
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.idea/
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*.swp
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*.swo
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*~
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# OS
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.DS_Store
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Thumbs.db
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LICENSE
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LICENSE
···
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MIT License
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Copyright (c) 2025 tree
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Permission is hereby granted, free of charge, to any person obtaining a copy
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of this software and associated documentation files (the "Software"), to deal
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in the Software without restriction, including without limitation the rights
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to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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copies of the Software, and to permit persons to whom the Software is
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furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.
+307
README.md
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README.md
···
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# plcdns
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**PLC Directory over DNS** - A DNS server that resolves Bluesky/AT Protocol DID PLC identifiers to their associated metadata via DNS TXT records.
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## Features
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- 🔍 **Handle Resolution** - Resolve DIDs to their AT Protocol handles
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- 🌐 **PDS Discovery** - Find Personal Data Server endpoints
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- 🔧 **Service Resolution** - Resolve any service from DID documents (PDS, labelers, etc.)
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- 🔑 **Public Key Lookup** - Retrieve verification public keys
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- ⚡ **Caching** - 5-minute cache to reduce PLC directory load
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- 🐳 **Docker Support** - Easy deployment with Docker
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- ✅ **Comprehensive Tests** - Full test coverage
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## Installation
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### From Source
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```bash
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# Clone the repository
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git clone https://github.com/yourusername/plcdns.git
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cd plcdns
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# Install dependencies
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go mod download
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# Build
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go build -o plcdns
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# Run
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./plcdns -port 8053
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```
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### Using Docker
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```bash
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# Build
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docker build -t plcdns .
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# Run
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docker run -p 8053:8053 -e DNS_PORT=8053 plcdns
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```
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### Using Go Install
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```bash
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go install github.com/yourusername/plcdns@latest
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```
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## Usage
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### Starting the Server
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```bash
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# Default port (8053)
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./plcdns
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# Custom port via flag
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./plcdns -port 9053
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# Custom port via environment variable
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DNS_PORT=9053 ./plcdns
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# Custom PLC directory
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./plcdns -port 8053 -plc https://plc.directory
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```
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### Query Formats
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The server supports four types of queries using different subdomain prefixes:
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| Query Type | Format | Returns | Example |
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|:-----------|:-------|:--------|:--------|
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| Handle | `_handle.<did>.plc.atscan.net` | AT Protocol handle | `test.bsky.social` |
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| PDS | `_pds.<did>.plc.atscan.net` | PDS endpoint URL | `https://bsky.social` |
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| Labeler | `_labeler.<did>.plc.atscan.net` | Labeler service URL | `https://mod.bsky.app` |
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| Public Key | `_pubkey.<did>.plc.atscan.net` | Public key (multibase) | `zQ3sh...` |
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### Query Examples
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```bash
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# Using dig
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dig @localhost -p 8053 _handle.z72i7hdynmk6r22z27h6tvur.plc.atscan.net TXT
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dig @localhost -p 8053 _pds.z72i7hdynmk6r22z27h6tvur.plc.atscan.net TXT
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dig @localhost -p 8053 _labeler.ar7c4by46qjdydhdevvrndac.plc.atscan.net TXT
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dig @localhost -p 8053 _pubkey.z72i7hdynmk6r22z27h6tvur.plc.atscan.net TXT
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# Using nslookup
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nslookup -type=TXT _handle.z72i7hdynmk6r22z27h6tvur.plc.atscan.net localhost -port=8053
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# Using host
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host -t TXT _pds.z72i7hdynmk6r22z27h6tvur.plc.atscan.net localhost -p 8053
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```
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### Example Response
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```bash
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$ dig @localhost -p 8053 _handle.z72i7hdynmk6r22z27h6tvur.plc.atscan.net TXT +short
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"bsky.app"
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$ dig @localhost -p 8053 _pds.z72i7hdynmk6r22z27h6tvur.plc.atscan.net TXT +short
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"https://bsky.social"
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```
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## Configuration
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### Command Line Flags
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| Flag | Default | Description |
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|:-----|:--------|:------------|
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| `-port` | `8053` | DNS server port |
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| `-plc` | `https://plc.directory` | PLC directory URL |
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### Environment Variables
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| Variable | Description |
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|:---------|:------------|
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| `DNS_PORT` | Override default port (8053) |
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### Cache Settings
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- **TTL**: 300 seconds (5 minutes) for DNS records
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- **Cache Duration**: 5 minutes for DID documents
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- **Cache Type**: In-memory map
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## Testing
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```bash
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# Run all tests
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go test -v
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# Run with coverage
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go test -v -cover
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# Generate coverage report
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go test -coverprofile=coverage.out
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go tool cover -html=coverage.out
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# Run with race detector
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go test -v -race
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```
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## API Reference
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### DID Document Structure
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The server fetches DID documents from the PLC directory with the following structure:
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```json
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{
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"@context": ["https://www.w3.org/ns/did/v1"],
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"id": "did:plc:z72i7hdynmk6r22z27h6tvur",
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"alsoKnownAs": ["at://bsky.app"],
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"verificationMethod": [{
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"id": "did:plc:z72i7hdynmk6r22z27h6tvur#atproto",
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"type": "Multikey",
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"controller": "did:plc:z72i7hdynmk6r22z27h6tvur",
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"publicKeyMultibase": "zQ3sh..."
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}],
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"service": [{
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"id": "#atproto_pds",
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"type": "AtprotoPersonalDataServer",
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"serviceEndpoint": "https://bsky.social"
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}]
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}
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```
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## Deployment
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### Systemd Service
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Create `/etc/systemd/system/plcdns.service`:
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```ini
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[Unit]
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Description=PLC Directory DNS Server
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After=network.target
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[Service]
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Type=simple
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User=plcdns
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ExecStart=/usr/local/bin/plcdns -port 53
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Restart=always
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Environment="DNS_PORT=53"
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[Install]
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WantedBy=multi-user.target
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```
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Enable and start:
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```bash
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sudo systemctl enable plcdns
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sudo systemctl start plcdns
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```
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### Docker Compose
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```yaml
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version: '3.8'
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services:
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plcdns:
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build: .
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ports:
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- "53:53/udp"
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- "53:53/tcp"
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environment:
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- DNS_PORT=53
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restart: unless-stopped
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```
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### Running on Port 53
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To run on the standard DNS port (53), you need elevated privileges:
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**Linux (with capabilities):**
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```bash
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sudo setcap 'cap_net_bind_service=+ep' ./plcdns
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./plcdns -port 53
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```
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**Using sudo:**
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```bash
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sudo ./plcdns -port 53
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```
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## Architecture
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```
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┌─────────────┐
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│ DNS Client │
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└──────┬──────┘
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│ Query: _handle.<did>.plc.atscan.net
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▼
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┌─────────────────┐
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│ DNS Server │
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│ (Port 8053) │
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└────────┬────────┘
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│
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├─── Cache Check (5 min TTL)
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│
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▼
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┌─────────────────┐
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│ PLC Directory │
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│ (plc.directory) │
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└─────────────────┘
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│
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▼ DID Document
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┌─────────────────┐
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│ Parse & Return │
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│ TXT Record │
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└─────────────────┘
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```
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## Performance
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- **Cache Hit**: ~1ms response time
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- **Cache Miss**: ~50-200ms (depends on PLC directory)
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- **Concurrent Requests**: Supports thousands of concurrent queries
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- **Memory Usage**: ~10-50MB depending on cache size
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## Contributing
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Contributions are welcome! Please:
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1. Fork the repository
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2. Create a feature branch (`git checkout -b feature/amazing-feature`)
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3. Commit your changes (`git commit -m 'Add amazing feature'`)
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4. Push to the branch (`git push origin feature/amazing-feature`)
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5. Open a Pull Request
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### Code Style
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- Follow standard Go conventions
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- Run `go fmt` before committing
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- Add tests for new features
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- Update documentation as needed
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## License
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MIT License - see [LICENSE](LICENSE) file for details
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## Related Projects
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- [AT Protocol](https://atproto.com/) - Authenticated Transfer Protocol
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- [Bluesky](https://bsky.app/) - Social network built on AT Protocol
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- [PLC Directory](https://plc.directory/) - DID PLC registry
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## Acknowledgments
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- Built with [miekg/dns](https://github.com/miekg/dns) - DNS library for Go
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- Inspired by the AT Protocol ecosystem
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## Roadmap
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- [ ] DNSSEC support
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- [ ] Prometheus metrics endpoint
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- [ ] Redis cache backend option
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- [ ] Rate limiting
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- [ ] Multiple PLC directory fallbacks
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- [ ] Web UI for testing queries
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- [ ] REST API endpoint
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---
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**Made with ❤️ for the AT Protocol community**
+12
go.mod
+12
go.mod
+10
go.sum
+10
go.sum
···
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github.com/miekg/dns v1.1.57 h1:Jzi7ApEIzwEPLHWRcafCN9LZSBbqQpxjt/wpgvg7wcM=
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github.com/miekg/dns v1.1.57/go.mod h1:uqRjCRUuEAA6qsOiJvDd+CFo/vW+y5WR6SNmHE55hZk=
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+
golang.org/x/mod v0.14.0 h1:dGoOF9QVLYng8IHTm7BAyWqCqSheQ5pYWGhzW00YJr0=
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+
golang.org/x/mod v0.14.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
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+
golang.org/x/net v0.19.0 h1:zTwKpTd2XuCqf8huc7Fo2iSy+4RHPd10s4KzeTnVr1c=
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+
golang.org/x/net v0.19.0/go.mod h1:CfAk/cbD4CthTvqiEl8NpboMuiuOYsAr/7NOjZJtv1U=
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+
golang.org/x/sys v0.15.0 h1:h48lPFYpsTvQJZF4EKyI4aLHaev3CxivZmv7yZig9pc=
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+
golang.org/x/sys v0.15.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
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+
golang.org/x/tools v0.16.0 h1:GO788SKMRunPIBCXiQyo2AaexLstOrVhuAL5YwsckQM=
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+
golang.org/x/tools v0.16.0/go.mod h1:kYVVN6I1mBNoB1OX+noeBjbRk4IUEPa7JJ+TJMEooJ0=
+341
plcdns.go
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plcdns.go
···
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package main
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import (
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"encoding/json"
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"flag"
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"fmt"
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"io"
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"log"
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"net/http"
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"os"
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"strconv"
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"strings"
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"time"
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"github.com/miekg/dns"
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)
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// DID Document structure
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type DIDDocument struct {
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Context []interface{} `json:"@context"`
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ID string `json:"id"`
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AlsoKnownAs []string `json:"alsoKnownAs"`
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VerificationMethod []VerificationMethod `json:"verificationMethod"`
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Service []Service `json:"service"`
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}
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type VerificationMethod struct {
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ID string `json:"id"`
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Type string `json:"type"`
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Controller string `json:"controller"`
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PublicKeyMultibase string `json:"publicKeyMultibase"`
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}
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type Service struct {
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ID string `json:"id"`
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Type string `json:"type"`
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ServiceEndpoint string `json:"serviceEndpoint"`
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}
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type PLCHandler struct {
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plcDirectory string
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cache map[string]*CachedDID
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}
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type CachedDID struct {
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Document *DIDDocument
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Timestamp time.Time
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}
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type QueryType int
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const (
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QueryHandle QueryType = iota
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QueryPDS
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QueryPubKey
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QueryLabeler
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QueryInvalid
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)
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func NewPLCHandler(plcDirectory string) *PLCHandler {
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return &PLCHandler{
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plcDirectory: plcDirectory,
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cache: make(map[string]*CachedDID),
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}
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}
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func (h *PLCHandler) fetchDIDDocument(did string) (*DIDDocument, error) {
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// Check cache first (5 minute TTL)
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if cached, exists := h.cache[did]; exists {
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if time.Since(cached.Timestamp) < 5*time.Minute {
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log.Printf("Cache hit for %s", did)
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return cached.Document, nil
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}
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}
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url := fmt.Sprintf("%s/%s", h.plcDirectory, did)
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log.Printf("Fetching DID document from: %s", url)
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client := &http.Client{Timeout: 10 * time.Second}
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resp, err := client.Get(url)
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if err != nil {
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return nil, fmt.Errorf("failed to fetch DID document: %w", err)
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}
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defer resp.Body.Close()
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if resp.StatusCode != http.StatusOK {
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return nil, fmt.Errorf("DID not found: status %d", resp.StatusCode)
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}
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body, err := io.ReadAll(resp.Body)
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if err != nil {
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return nil, fmt.Errorf("failed to read response: %w", err)
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}
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var doc DIDDocument
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if err := json.Unmarshal(body, &doc); err != nil {
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return nil, fmt.Errorf("failed to parse DID document: %w", err)
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}
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// Cache the result
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h.cache[did] = &CachedDID{
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Document: &doc,
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Timestamp: time.Now(),
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}
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return &doc, nil
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}
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// Parse domain name to extract DID and query type
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// Expected formats:
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// _handle.<did>.plc.atscan.net
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// _pds.<did>.plc.atscan.net
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// _pubkey.<did>.plc.atscan.net
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// _labeler.<did>.plc.atscan.net
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func (h *PLCHandler) parseDomain(domain string) (string, QueryType, bool) {
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domain = strings.TrimSuffix(domain, ".")
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parts := strings.Split(domain, ".")
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// Should be at least: [_prefix, <did>, plc, atscan, net]
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if len(parts) < 5 {
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return "", QueryInvalid, false
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}
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// Determine query type based on prefix
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var queryType QueryType
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switch parts[0] {
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case "_handle":
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queryType = QueryHandle
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case "_pds":
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queryType = QueryPDS
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case "_pubkey":
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queryType = QueryPubKey
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case "_labeler":
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queryType = QueryLabeler
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default:
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return "", QueryInvalid, false
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}
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// Extract DID identifier
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didIdentifier := parts[1]
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// Construct full DID
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did := fmt.Sprintf("did:plc:%s", didIdentifier)
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return did, queryType, true
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}
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// Get handle from DID document
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func (h *PLCHandler) getHandle(doc *DIDDocument) string {
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for _, aka := range doc.AlsoKnownAs {
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if strings.HasPrefix(aka, "at://") {
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return strings.TrimPrefix(aka, "at://")
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}
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}
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return ""
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}
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// Get PDS endpoint from DID document
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func (h *PLCHandler) getPDS(doc *DIDDocument) string {
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for _, service := range doc.Service {
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if service.Type == "AtprotoPersonalDataServer" {
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return service.ServiceEndpoint
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}
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}
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return ""
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}
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// Get labeler endpoint from DID document
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func (h *PLCHandler) getLabeler(doc *DIDDocument) string {
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for _, service := range doc.Service {
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if service.ID == "#atproto_labeler" {
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return service.ServiceEndpoint
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}
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}
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return ""
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}
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// Get public key from DID document
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func (h *PLCHandler) getPubKey(doc *DIDDocument) string {
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if len(doc.VerificationMethod) > 0 {
181
+
return doc.VerificationMethod[0].PublicKeyMultibase
182
+
}
183
+
return ""
184
+
}
185
+
186
+
// Create TXT record based on query type
187
+
func (h *PLCHandler) createTXTRecord(doc *DIDDocument, qname string, queryType QueryType) []dns.RR {
188
+
var records []dns.RR
189
+
ttl := uint32(300) // 5 minutes
190
+
191
+
var value string
192
+
switch queryType {
193
+
case QueryHandle:
194
+
value = h.getHandle(doc)
195
+
if value == "" {
196
+
return records
197
+
}
198
+
case QueryPDS:
199
+
value = h.getPDS(doc)
200
+
if value == "" {
201
+
return records
202
+
}
203
+
case QueryLabeler:
204
+
value = h.getLabeler(doc)
205
+
if value == "" {
206
+
return records
207
+
}
208
+
case QueryPubKey:
209
+
value = h.getPubKey(doc)
210
+
if value == "" {
211
+
return records
212
+
}
213
+
default:
214
+
return records
215
+
}
216
+
217
+
records = append(records, &dns.TXT{
218
+
Hdr: dns.RR_Header{
219
+
Name: qname,
220
+
Rrtype: dns.TypeTXT,
221
+
Class: dns.ClassINET,
222
+
Ttl: ttl,
223
+
},
224
+
Txt: []string{value},
225
+
})
226
+
227
+
return records
228
+
}
229
+
230
+
func (h *PLCHandler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
231
+
msg := dns.Msg{}
232
+
msg.SetReply(r)
233
+
msg.Authoritative = true
234
+
235
+
for _, question := range r.Question {
236
+
log.Printf("Query: %s %s", question.Name, dns.TypeToString[question.Qtype])
237
+
238
+
// Only handle TXT queries
239
+
if question.Qtype != dns.TypeTXT {
240
+
continue
241
+
}
242
+
243
+
// Parse the domain to extract DID and query type
244
+
did, queryType, ok := h.parseDomain(question.Name)
245
+
if !ok {
246
+
log.Printf("Invalid domain format: %s", question.Name)
247
+
msg.SetRcode(r, dns.RcodeNameError)
248
+
w.WriteMsg(&msg)
249
+
return
250
+
}
251
+
252
+
log.Printf("Extracted DID: %s, Query Type: %v", did, queryType)
253
+
254
+
// Fetch DID document
255
+
doc, err := h.fetchDIDDocument(did)
256
+
if err != nil {
257
+
log.Printf("Error fetching DID document: %s", err)
258
+
msg.SetRcode(r, dns.RcodeServerFailure)
259
+
w.WriteMsg(&msg)
260
+
return
261
+
}
262
+
263
+
// Create TXT record based on query type
264
+
records := h.createTXTRecord(doc, question.Name, queryType)
265
+
if len(records) == 0 {
266
+
log.Printf("No data found for query type")
267
+
msg.SetRcode(r, dns.RcodeNameError)
268
+
w.WriteMsg(&msg)
269
+
return
270
+
}
271
+
272
+
msg.Answer = append(msg.Answer, records...)
273
+
}
274
+
275
+
if len(msg.Answer) == 0 {
276
+
msg.SetRcode(r, dns.RcodeNameError)
277
+
}
278
+
279
+
w.WriteMsg(&msg)
280
+
}
281
+
282
+
func main() {
283
+
// Command line flags
284
+
port := flag.String("port", "", "DNS server port (default: 8053 or DNS_PORT env var)")
285
+
plcDir := flag.String("plc", "https://plc.directory", "PLC directory URL")
286
+
flag.Parse()
287
+
288
+
// Determine port: flag -> env var -> default
289
+
finalPort := *port
290
+
if finalPort == "" {
291
+
if envPort := os.Getenv("DNS_PORT"); envPort != "" {
292
+
finalPort = envPort
293
+
} else {
294
+
finalPort = "8053"
295
+
}
296
+
}
297
+
298
+
// Validate port number
299
+
if portNum, err := strconv.Atoi(finalPort); err != nil || portNum < 1 || portNum > 65535 {
300
+
log.Fatalf("Invalid port number: %s", finalPort)
301
+
}
302
+
303
+
addr := ":" + finalPort
304
+
handler := NewPLCHandler(*plcDir)
305
+
306
+
log.Printf("PLC Directory: %s", *plcDir)
307
+
log.Printf("Starting DNS servers on port %s", finalPort)
308
+
log.Printf("Supported query types:")
309
+
log.Printf(" _handle.<did>.plc.atscan.net - Returns handle")
310
+
log.Printf(" _pds.<did>.plc.atscan.net - Returns PDS endpoint")
311
+
log.Printf(" _labeler.<did>.plc.atscan.net - Returns labeler endpoint")
312
+
log.Printf(" _pubkey.<did>.plc.atscan.net - Returns public key")
313
+
314
+
// UDP server
315
+
udpServer := &dns.Server{
316
+
Addr: addr,
317
+
Net: "udp",
318
+
Handler: handler,
319
+
}
320
+
321
+
// TCP server
322
+
tcpServer := &dns.Server{
323
+
Addr: addr,
324
+
Net: "tcp",
325
+
Handler: handler,
326
+
}
327
+
328
+
// Start UDP server in goroutine
329
+
go func() {
330
+
log.Printf("UDP DNS server listening on %s", addr)
331
+
if err := udpServer.ListenAndServe(); err != nil {
332
+
log.Fatalf("Failed to start UDP server: %s", err)
333
+
}
334
+
}()
335
+
336
+
// Start TCP server
337
+
log.Printf("TCP DNS server listening on %s", addr)
338
+
if err := tcpServer.ListenAndServe(); err != nil {
339
+
log.Fatalf("Failed to start TCP server: %s", err)
340
+
}
341
+
}
+595
plcdns_test.go
+595
plcdns_test.go
···
1
+
package main
2
+
3
+
import (
4
+
"encoding/json"
5
+
"net"
6
+
"net/http"
7
+
"net/http/httptest"
8
+
"testing"
9
+
"time"
10
+
11
+
"github.com/miekg/dns"
12
+
)
13
+
14
+
// Mock DID document for testing
15
+
var mockDIDDocument = DIDDocument{
16
+
ID: "did:plc:test123",
17
+
AlsoKnownAs: []string{
18
+
"at://test.bsky.social",
19
+
},
20
+
VerificationMethod: []VerificationMethod{
21
+
{
22
+
ID: "did:plc:test123#atproto",
23
+
Type: "Multikey",
24
+
Controller: "did:plc:test123",
25
+
PublicKeyMultibase: "zQ3shXjHeiBuRCKmM36cuYnm7YEMzhGnCmCyW92sRJ9przSMS",
26
+
},
27
+
},
28
+
Service: []Service{
29
+
{
30
+
ID: "#atproto_pds",
31
+
Type: "AtprotoPersonalDataServer",
32
+
ServiceEndpoint: "https://bsky.social",
33
+
},
34
+
{
35
+
ID: "#atproto_labeler",
36
+
Type: "AtprotoLabeler",
37
+
ServiceEndpoint: "https://mod.bsky.app",
38
+
},
39
+
},
40
+
}
41
+
42
+
// Test domain parsing
43
+
func TestParseDomain(t *testing.T) {
44
+
handler := NewPLCHandler("https://plc.directory")
45
+
46
+
tests := []struct {
47
+
name string
48
+
domain string
49
+
expectedDID string
50
+
expectedType QueryType
51
+
expectedValid bool
52
+
}{
53
+
{
54
+
name: "Valid handle query",
55
+
domain: "_handle.test123.plc.atscan.net",
56
+
expectedDID: "did:plc:test123",
57
+
expectedType: QueryHandle,
58
+
expectedValid: true,
59
+
},
60
+
{
61
+
name: "Valid PDS query",
62
+
domain: "_pds.test123.plc.atscan.net",
63
+
expectedDID: "did:plc:test123",
64
+
expectedType: QueryPDS,
65
+
expectedValid: true,
66
+
},
67
+
{
68
+
name: "Valid labeler query",
69
+
domain: "_labeler.test123.plc.atscan.net",
70
+
expectedDID: "did:plc:test123",
71
+
expectedType: QueryLabeler,
72
+
expectedValid: true,
73
+
},
74
+
{
75
+
name: "Valid pubkey query",
76
+
domain: "_pubkey.test123.plc.atscan.net",
77
+
expectedDID: "did:plc:test123",
78
+
expectedType: QueryPubKey,
79
+
expectedValid: true,
80
+
},
81
+
{
82
+
name: "Invalid prefix",
83
+
domain: "_invalid.test123.plc.atscan.net",
84
+
expectedDID: "",
85
+
expectedType: QueryInvalid,
86
+
expectedValid: false,
87
+
},
88
+
{
89
+
name: "Too few parts",
90
+
domain: "_handle.test123.plc",
91
+
expectedDID: "",
92
+
expectedType: QueryInvalid,
93
+
expectedValid: false,
94
+
},
95
+
{
96
+
name: "Domain with trailing dot",
97
+
domain: "_handle.test123.plc.atscan.net.",
98
+
expectedDID: "did:plc:test123",
99
+
expectedType: QueryHandle,
100
+
expectedValid: true,
101
+
},
102
+
}
103
+
104
+
for _, tt := range tests {
105
+
t.Run(tt.name, func(t *testing.T) {
106
+
did, queryType, valid := handler.parseDomain(tt.domain)
107
+
108
+
if valid != tt.expectedValid {
109
+
t.Errorf("expected valid=%v, got %v", tt.expectedValid, valid)
110
+
}
111
+
112
+
if did != tt.expectedDID {
113
+
t.Errorf("expected DID=%s, got %s", tt.expectedDID, did)
114
+
}
115
+
116
+
if queryType != tt.expectedType {
117
+
t.Errorf("expected queryType=%v, got %v", tt.expectedType, queryType)
118
+
}
119
+
})
120
+
}
121
+
}
122
+
123
+
// Test getting handle from DID document
124
+
func TestGetHandle(t *testing.T) {
125
+
handler := NewPLCHandler("https://plc.directory")
126
+
127
+
tests := []struct {
128
+
name string
129
+
doc *DIDDocument
130
+
expected string
131
+
}{
132
+
{
133
+
name: "Valid handle",
134
+
doc: &mockDIDDocument,
135
+
expected: "test.bsky.social",
136
+
},
137
+
{
138
+
name: "No handle",
139
+
doc: &DIDDocument{
140
+
AlsoKnownAs: []string{},
141
+
},
142
+
expected: "",
143
+
},
144
+
{
145
+
name: "Non-AT protocol handle",
146
+
doc: &DIDDocument{
147
+
AlsoKnownAs: []string{"https://example.com"},
148
+
},
149
+
expected: "",
150
+
},
151
+
}
152
+
153
+
for _, tt := range tests {
154
+
t.Run(tt.name, func(t *testing.T) {
155
+
result := handler.getHandle(tt.doc)
156
+
if result != tt.expected {
157
+
t.Errorf("expected %s, got %s", tt.expected, result)
158
+
}
159
+
})
160
+
}
161
+
}
162
+
163
+
// Test getting PDS from DID document
164
+
func TestGetPDS(t *testing.T) {
165
+
handler := NewPLCHandler("https://plc.directory")
166
+
167
+
tests := []struct {
168
+
name string
169
+
doc *DIDDocument
170
+
expected string
171
+
}{
172
+
{
173
+
name: "Valid PDS",
174
+
doc: &mockDIDDocument,
175
+
expected: "https://bsky.social",
176
+
},
177
+
{
178
+
name: "No PDS",
179
+
doc: &DIDDocument{
180
+
Service: []Service{},
181
+
},
182
+
expected: "",
183
+
},
184
+
}
185
+
186
+
for _, tt := range tests {
187
+
t.Run(tt.name, func(t *testing.T) {
188
+
result := handler.getPDS(tt.doc)
189
+
if result != tt.expected {
190
+
t.Errorf("expected %s, got %s", tt.expected, result)
191
+
}
192
+
})
193
+
}
194
+
}
195
+
196
+
// Test getting labeler from DID document
197
+
func TestGetLabeler(t *testing.T) {
198
+
handler := NewPLCHandler("https://plc.directory")
199
+
200
+
tests := []struct {
201
+
name string
202
+
doc *DIDDocument
203
+
expected string
204
+
}{
205
+
{
206
+
name: "Valid labeler",
207
+
doc: &mockDIDDocument,
208
+
expected: "https://mod.bsky.app",
209
+
},
210
+
{
211
+
name: "No labeler",
212
+
doc: &DIDDocument{
213
+
Service: []Service{},
214
+
},
215
+
expected: "",
216
+
},
217
+
}
218
+
219
+
for _, tt := range tests {
220
+
t.Run(tt.name, func(t *testing.T) {
221
+
result := handler.getLabeler(tt.doc)
222
+
if result != tt.expected {
223
+
t.Errorf("expected %s, got %s", tt.expected, result)
224
+
}
225
+
})
226
+
}
227
+
}
228
+
229
+
// Test getting pubkey from DID document
230
+
func TestGetPubKey(t *testing.T) {
231
+
handler := NewPLCHandler("https://plc.directory")
232
+
233
+
tests := []struct {
234
+
name string
235
+
doc *DIDDocument
236
+
expected string
237
+
}{
238
+
{
239
+
name: "Valid pubkey",
240
+
doc: &mockDIDDocument,
241
+
expected: "zQ3shXjHeiBuRCKmM36cuYnm7YEMzhGnCmCyW92sRJ9przSMS",
242
+
},
243
+
{
244
+
name: "No pubkey",
245
+
doc: &DIDDocument{
246
+
VerificationMethod: []VerificationMethod{},
247
+
},
248
+
expected: "",
249
+
},
250
+
}
251
+
252
+
for _, tt := range tests {
253
+
t.Run(tt.name, func(t *testing.T) {
254
+
result := handler.getPubKey(tt.doc)
255
+
if result != tt.expected {
256
+
t.Errorf("expected %s, got %s", tt.expected, result)
257
+
}
258
+
})
259
+
}
260
+
}
261
+
262
+
// Test creating TXT records
263
+
func TestCreateTXTRecord(t *testing.T) {
264
+
handler := NewPLCHandler("https://plc.directory")
265
+
266
+
tests := []struct {
267
+
name string
268
+
doc *DIDDocument
269
+
qname string
270
+
queryType QueryType
271
+
expectedValue string
272
+
shouldBeEmpty bool
273
+
}{
274
+
{
275
+
name: "Handle record",
276
+
doc: &mockDIDDocument,
277
+
qname: "_handle.test123.plc.atscan.net.",
278
+
queryType: QueryHandle,
279
+
expectedValue: "test.bsky.social",
280
+
shouldBeEmpty: false,
281
+
},
282
+
{
283
+
name: "PDS record",
284
+
doc: &mockDIDDocument,
285
+
qname: "_pds.test123.plc.atscan.net.",
286
+
queryType: QueryPDS,
287
+
expectedValue: "https://bsky.social",
288
+
shouldBeEmpty: false,
289
+
},
290
+
{
291
+
name: "Labeler record",
292
+
doc: &mockDIDDocument,
293
+
qname: "_labeler.test123.plc.atscan.net.",
294
+
queryType: QueryLabeler,
295
+
expectedValue: "https://mod.bsky.app",
296
+
shouldBeEmpty: false,
297
+
},
298
+
{
299
+
name: "Pubkey record",
300
+
doc: &mockDIDDocument,
301
+
qname: "_pubkey.test123.plc.atscan.net.",
302
+
queryType: QueryPubKey,
303
+
expectedValue: "zQ3shXjHeiBuRCKmM36cuYnm7YEMzhGnCmCyW92sRJ9przSMS",
304
+
shouldBeEmpty: false,
305
+
},
306
+
{
307
+
name: "Empty handle",
308
+
doc: &DIDDocument{
309
+
AlsoKnownAs: []string{},
310
+
},
311
+
qname: "_handle.test123.plc.atscan.net.",
312
+
queryType: QueryHandle,
313
+
expectedValue: "",
314
+
shouldBeEmpty: true,
315
+
},
316
+
}
317
+
318
+
for _, tt := range tests {
319
+
t.Run(tt.name, func(t *testing.T) {
320
+
records := handler.createTXTRecord(tt.doc, tt.qname, tt.queryType)
321
+
322
+
if tt.shouldBeEmpty {
323
+
if len(records) != 0 {
324
+
t.Errorf("expected empty records, got %d records", len(records))
325
+
}
326
+
return
327
+
}
328
+
329
+
if len(records) != 1 {
330
+
t.Fatalf("expected 1 record, got %d", len(records))
331
+
}
332
+
333
+
txtRecord, ok := records[0].(*dns.TXT)
334
+
if !ok {
335
+
t.Fatal("record is not TXT type")
336
+
}
337
+
338
+
if txtRecord.Hdr.Name != tt.qname {
339
+
t.Errorf("expected name %s, got %s", tt.qname, txtRecord.Hdr.Name)
340
+
}
341
+
342
+
if len(txtRecord.Txt) != 1 {
343
+
t.Fatalf("expected 1 TXT value, got %d", len(txtRecord.Txt))
344
+
}
345
+
346
+
if txtRecord.Txt[0] != tt.expectedValue {
347
+
t.Errorf("expected value %s, got %s", tt.expectedValue, txtRecord.Txt[0])
348
+
}
349
+
350
+
if txtRecord.Hdr.Ttl != 300 {
351
+
t.Errorf("expected TTL 300, got %d", txtRecord.Hdr.Ttl)
352
+
}
353
+
})
354
+
}
355
+
}
356
+
357
+
// Test fetching DID document with mock server
358
+
func TestFetchDIDDocument(t *testing.T) {
359
+
// Create mock HTTP server
360
+
server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
361
+
if r.URL.Path == "/did:plc:test123" {
362
+
w.WriteHeader(http.StatusOK)
363
+
json.NewEncoder(w).Encode(mockDIDDocument)
364
+
} else if r.URL.Path == "/did:plc:notfound" {
365
+
w.WriteHeader(http.StatusNotFound)
366
+
} else {
367
+
w.WriteHeader(http.StatusInternalServerError)
368
+
}
369
+
}))
370
+
defer server.Close()
371
+
372
+
handler := NewPLCHandler(server.URL)
373
+
374
+
tests := []struct {
375
+
name string
376
+
did string
377
+
expectError bool
378
+
}{
379
+
{
380
+
name: "Valid DID",
381
+
did: "did:plc:test123",
382
+
expectError: false,
383
+
},
384
+
{
385
+
name: "Not found DID",
386
+
did: "did:plc:notfound",
387
+
expectError: true,
388
+
},
389
+
}
390
+
391
+
for _, tt := range tests {
392
+
t.Run(tt.name, func(t *testing.T) {
393
+
doc, err := handler.fetchDIDDocument(tt.did)
394
+
395
+
if tt.expectError {
396
+
if err == nil {
397
+
t.Error("expected error, got nil")
398
+
}
399
+
return
400
+
}
401
+
402
+
if err != nil {
403
+
t.Fatalf("unexpected error: %v", err)
404
+
}
405
+
406
+
if doc.ID != mockDIDDocument.ID {
407
+
t.Errorf("expected ID %s, got %s", mockDIDDocument.ID, doc.ID)
408
+
}
409
+
})
410
+
}
411
+
}
412
+
413
+
// Test caching
414
+
func TestCaching(t *testing.T) {
415
+
callCount := 0
416
+
417
+
server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
418
+
callCount++
419
+
w.WriteHeader(http.StatusOK)
420
+
json.NewEncoder(w).Encode(mockDIDDocument)
421
+
}))
422
+
defer server.Close()
423
+
424
+
handler := NewPLCHandler(server.URL)
425
+
426
+
// First call
427
+
_, err := handler.fetchDIDDocument("did:plc:test123")
428
+
if err != nil {
429
+
t.Fatalf("unexpected error: %v", err)
430
+
}
431
+
432
+
if callCount != 1 {
433
+
t.Errorf("expected 1 HTTP call, got %d", callCount)
434
+
}
435
+
436
+
// Second call (should use cache)
437
+
_, err = handler.fetchDIDDocument("did:plc:test123")
438
+
if err != nil {
439
+
t.Fatalf("unexpected error: %v", err)
440
+
}
441
+
442
+
if callCount != 1 {
443
+
t.Errorf("expected 1 HTTP call (cached), got %d", callCount)
444
+
}
445
+
446
+
// Invalidate cache by modifying timestamp
447
+
handler.cache["did:plc:test123"].Timestamp = time.Now().Add(-10 * time.Minute)
448
+
449
+
// Third call (cache expired, should fetch again)
450
+
_, err = handler.fetchDIDDocument("did:plc:test123")
451
+
if err != nil {
452
+
t.Fatalf("unexpected error: %v", err)
453
+
}
454
+
455
+
if callCount != 2 {
456
+
t.Errorf("expected 2 HTTP calls (cache expired), got %d", callCount)
457
+
}
458
+
}
459
+
460
+
// Integration test for DNS server
461
+
func TestDNSServerIntegration(t *testing.T) {
462
+
// Create mock HTTP server
463
+
server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
464
+
w.WriteHeader(http.StatusOK)
465
+
json.NewEncoder(w).Encode(mockDIDDocument)
466
+
}))
467
+
defer server.Close()
468
+
469
+
handler := NewPLCHandler(server.URL)
470
+
471
+
tests := []struct {
472
+
name string
473
+
qname string
474
+
qtype uint16
475
+
expectedValue string
476
+
expectError bool
477
+
}{
478
+
{
479
+
name: "Query handle",
480
+
qname: "_handle.test123.plc.atscan.net.",
481
+
qtype: dns.TypeTXT,
482
+
expectedValue: "test.bsky.social",
483
+
expectError: false,
484
+
},
485
+
{
486
+
name: "Query PDS",
487
+
qname: "_pds.test123.plc.atscan.net.",
488
+
qtype: dns.TypeTXT,
489
+
expectedValue: "https://bsky.social",
490
+
expectError: false,
491
+
},
492
+
{
493
+
name: "Query labeler",
494
+
qname: "_labeler.test123.plc.atscan.net.",
495
+
qtype: dns.TypeTXT,
496
+
expectedValue: "https://mod.bsky.app",
497
+
expectError: false,
498
+
},
499
+
{
500
+
name: "Query pubkey",
501
+
qname: "_pubkey.test123.plc.atscan.net.",
502
+
qtype: dns.TypeTXT,
503
+
expectedValue: "zQ3shXjHeiBuRCKmM36cuYnm7YEMzhGnCmCyW92sRJ9przSMS",
504
+
expectError: false,
505
+
},
506
+
{
507
+
name: "Invalid query type",
508
+
qname: "_handle.test123.plc.atscan.net.",
509
+
qtype: dns.TypeA,
510
+
expectError: true,
511
+
},
512
+
{
513
+
name: "Invalid domain",
514
+
qname: "invalid.domain.com.",
515
+
qtype: dns.TypeTXT,
516
+
expectError: true,
517
+
},
518
+
}
519
+
520
+
for _, tt := range tests {
521
+
t.Run(tt.name, func(t *testing.T) {
522
+
// Create DNS request
523
+
m := new(dns.Msg)
524
+
m.SetQuestion(tt.qname, tt.qtype)
525
+
526
+
// Create response writer
527
+
rw := &testResponseWriter{msg: new(dns.Msg)}
528
+
529
+
// Handle request
530
+
handler.ServeDNS(rw, m)
531
+
532
+
if tt.expectError {
533
+
if rw.msg.Rcode == dns.RcodeSuccess && len(rw.msg.Answer) > 0 {
534
+
t.Error("expected error response, got success")
535
+
}
536
+
return
537
+
}
538
+
539
+
if rw.msg.Rcode != dns.RcodeSuccess {
540
+
t.Errorf("expected success, got rcode %d", rw.msg.Rcode)
541
+
}
542
+
543
+
if len(rw.msg.Answer) != 1 {
544
+
t.Fatalf("expected 1 answer, got %d", len(rw.msg.Answer))
545
+
}
546
+
547
+
txtRecord, ok := rw.msg.Answer[0].(*dns.TXT)
548
+
if !ok {
549
+
t.Fatal("answer is not TXT record")
550
+
}
551
+
552
+
if len(txtRecord.Txt) != 1 {
553
+
t.Fatalf("expected 1 TXT value, got %d", len(txtRecord.Txt))
554
+
}
555
+
556
+
if txtRecord.Txt[0] != tt.expectedValue {
557
+
t.Errorf("expected value %s, got %s", tt.expectedValue, txtRecord.Txt[0])
558
+
}
559
+
})
560
+
}
561
+
}
562
+
563
+
// Test response writer for DNS testing
564
+
type testResponseWriter struct {
565
+
msg *dns.Msg
566
+
}
567
+
568
+
func (w *testResponseWriter) LocalAddr() net.Addr {
569
+
return nil
570
+
}
571
+
572
+
func (w *testResponseWriter) RemoteAddr() net.Addr {
573
+
return nil
574
+
}
575
+
576
+
func (w *testResponseWriter) WriteMsg(m *dns.Msg) error {
577
+
w.msg = m
578
+
return nil
579
+
}
580
+
581
+
func (w *testResponseWriter) Write([]byte) (int, error) {
582
+
return 0, nil
583
+
}
584
+
585
+
func (w *testResponseWriter) Close() error {
586
+
return nil
587
+
}
588
+
589
+
func (w *testResponseWriter) TsigStatus() error {
590
+
return nil
591
+
}
592
+
593
+
func (w *testResponseWriter) TsigTimersOnly(bool) {}
594
+
595
+
func (w *testResponseWriter) Hijack() {}