Rendezvous Key-Value Server

A lightweight, public key-value store server designed as a rendezvous/bootstrap point for mesh networks, distributed applications, and general-purpose key-value storage without registration.

🌐 Publicly Hosted Instance

Public instance is available at: https://rendezvous.jipok.ru

• Key limit: 100 bytes
• Value limit: 1000 bytes
• Rate limit: 17 tokens per minute (get=1, set/los/cas/casoc = 3)
• Expire time: 2 hours (configurable, per-entry TTL)
• Max entries: 100,000

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🚀 API Usage

⚡ All requests include the header:

• X-Client-Ip — your detected public IP

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Retrieve a Value

curl https://rendezvous.jipok.ru/get/your-key

If the key exists, server returns the stored value with an additional header:

• X-Expires-At — Unix timestamp when key will expire

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Store or Update a Value

curl -X POST -d "your-data-here" https://rendezvous.jipok.ru/set/your-key

• Updates existing value (if not protected by secret)
• Or creates a new key-value pair
• Query parameter ttl can be provided (e.g. ?ttl=30m). If omitted, defaults to max (2h). TTL will be capped at expireDuration.

Example:

curl -X POST -d "session-token-123" "https://rendezvous.jipok.ru/set/my-key?ttl=30m"

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Load Or Store (Atomic Get-Or-Create)

curl -X POST -d "initial-value" https://rendezvous.jipok.ru/los/unique-key

Behavior:

• If key does not exist, it gets created with your value (OK returned).
• If key already exists, server replies with its current value instead (does not overwrite).

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Compare-And-Swap (CAS)

Useful for safe concurrent updates.

curl -X POST -d "new-value" \
     -H "X-Expected-Value: old-value" \
     https://rendezvous.jipok.ru/cas/some-key

• Operation succeeds only if current value matches X-Expected-Value.
• On mismatch, server returns the existing value with HTTP 409 Conflict.

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Compare-And-Swap Or Create (CASOC)

Atomic variant that allows creation when key doesn’t exist:

curl -X POST -d "my-value" \
     -H "X-Expected-Value: old-value" \
     https://rendezvous.jipok.ru/casoc/my-key

• If key does not exist, it is created.
• If key exists but value differs, returns existing value (409).

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Protecting Values with Owner Secret

To prevent unauthorized modification, attach X-Owner-Secret header when writing:

# Store with protection
curl -X POST -d "protected-data" \
     -H "X-Owner-Secret: my-secret" \
     https://rendezvous.jipok.ru/set/secure-key

• Only requests with the same secret can update the value
• New keys without secret can be "claimed" by adding a secret in the first update
• Size of value + secret must not exceed the configured value limit (1000 bytes default)

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IP-Protected Keys

Keys under /set/ip/ and friends will be automatically prefixed with your public IP.

Example:

# Store something under your IP namespace
curl -X POST -d "my server instance" https://rendezvous.jipok.ru/set/ip/service1

# Set on IP=20.18.12.10 → Actual key = ip/20.18.12.10/service1
# Response body will be OK, and your public IP will be available in the header X-Client-Ip.

Retrieve:

curl https://rendezvous.jipok.ru/get/ip/20.18.12.10/service1

This ensures only that IP can update ip/... keys.

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📋 Use Cases

• Peer Discovery: Initial peer bootstrap
• Configuration Distribution: Share small configs
• Ephemeral Data Exchange: Temporary messages or secrets
• IoT Coordination: Lightweight communication channel
• Secure Self-Identification: Publish info under IP-protected keys

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🔧 Self-hosted

Using prebuilt

wget https://github.com/Jipok/rendezvous/releases/latest/download/rendezvous-server
chmod +x rendezvous-server
./rendezvous-server

Using Go

git clone https://github.com/Jipok/rendezvous
cd rendezvous
go build
./rendezvous-server

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🔑 Features

• No Registration — just use it
• Simple HTTP API — minimal HTTP GET/POST interface
• TTL Support — configurable expiration per key
• Value Protection — optional secret protection
• Ephemeral Storage — keys expire automatically
• Rate Limited — tokens per-IP
• Zero Dependencies — no external DB, just one binary

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⚙️ Configuration Options

Flag	Default	Description
-maxKeySize	100	Maximum key length in bytes
-maxValueSize	1000	Maximum value length in bytes (including secret)
-maxNumKV	100000	Maximum number of key-value pairs
-expireDuration	2h	Maximum/default TTL per key
-resetDuration	1m	Time between rate limit resets
-saveDuration	30m	Interval between periodic persistence saves
-maxRequests	17	Max tokens per IP per window (SET=3, GET=1)
-port	80	Server listening port
-l	0.0.0.0	Listen address (interface)
-disableLocalIPWarning	false	Disable warnings for requests from localhost

Example:

./rendezvous-server -maxValueSize 4096 -expireDuration 24h -port 9000

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⚠️ Limitations

• No Encryption — use HTTPS/TLS for security
• IPv4 Only — rate limiting and IP-protected ops work only with IPv4