Documentation

Ember

An in-memory key-value store with durable persistence.

Ember keeps your keys in memory for fast access and persists them to disk in the background. Reads and writes go through a small HTTP API, so any language can use it without a client library.

Keys can carry a time-to-live and are grouped into logical namespaces. When memory runs low, a configurable eviction policy decides what to drop first.

#Installation

Ember ships as one static binary. Place it on your host and start it:

# download and start
$ curl -sSL get.rainyblack.space/install | sh
$ ember serve --data /var/lib/ember
→ listening on :6100 · api ready

By default Ember binds to 127.0.0.1:6100. Put it behind your own reverse proxy to expose it over TLS.

#Quickstart

# set a key
$ curl -X PUT :6100/v1/kv/session -d 'abc123'
→ ok

# read it back
$ curl :6100/v1/kv/session
abc123

# delete it
$ curl -X DELETE :6100/v1/kv/session

#Configuration

Configure with flags, environment variables, or a small YAML file. Flags take precedence.

# ember.yaml
data:    /var/lib/ember
listen:  127.0.0.1:6100
log:     info
memory:
  eviction: lru

data — directory for the persistence log and snapshots.
listen — address the HTTP interface binds to.
memory.eviction — policy used when memory is full (lru, lfu, none).

#API reference

Every route lives under /v1/kv. Requests without a valid token return 401.

Method & path	Description
`GET /v1/kv/{key}`	Read a value.
`PUT /v1/kv/{key}`	Set a value (optional ttl header).
`DELETE /v1/kv/{key}`	Delete a key.
`GET /v1/kv/_scan`	Stream keys matching a prefix.
`GET /health`	Liveness probe. Returns 200 when the store is ready.

#CLI

The ember binary is both the server and the client.

Command	Description
`ember serve`	Start the store.
`ember get <key>`	Read a value.
`ember set <key> <value>`	Set a value.
`ember status`	Show memory use and hit rate.