Redis Compatibility
Use redis-cli, ioredis, go-redis, redis-py and other Redis clients against Flo.
Flo speaks RESP (the Redis serialization protocol) on the same TCP port as its native protocol. The Acceptor detects RESP by the leading byte (*, $, +, -, :) and dispatches to a translation layer that maps each command onto an equivalent Flo opcode. No proxy, no separate port, no additional configuration.
This makes Flo a drop-in target for tools that already speak Redis — redis-cli, RedisInsight, ioredis, go-redis, redis-py, Lettuce, etc. — for the subset of commands listed below.
Supported commands
Strings & basic KV
| Redis | Flo opcode | Notes |
|---|---|---|
GET key | kv_get | Returns nil if missing. |
SET key value | kv_put | |
SET key value EX seconds | kv_put + TTL | TTL TLV. |
SET key value NX | kv_put + if_not_exists | |
SET key value XX | kv_put + if_exists | |
DEL key [key ...] | kv_delete | Per-key. |
EXISTS key | kv_exists | |
EXPIRE key seconds | kv_touch | |
PEXPIRE key ms | kv_touch | Rounded down to seconds. |
PERSIST key | kv_persist | |
TTL key | (synthesized) | Computed from key metadata. |
Counters
| Redis | Flo opcode | Notes |
|---|---|---|
INCR key | kv_incr (delta=1) | |
INCRBY key n | kv_incr (delta=n) | Signed i64. |
DECR key | kv_incr (delta=-1) | |
DECRBY key n | kv_incr (delta=-n) |
A counter and a string value cannot share a key. Mixing returns WRONGTYPE-style Conflict.
JSON (RedisJSON-style)
| Redis | Flo opcode | Notes |
|---|---|---|
JSON.GET key [path] | kv_json_get | Path defaults to $. |
JSON.SET key path value | kv_json_set | Atomic per-Raft-entry sub-field set. |
JSON.DEL key [path] | kv_json_del |
Path syntax is a small JSONPath subset: $, .field, .field.nested, [index].
Scan
| Redis | Flo opcode | Notes |
|---|---|---|
SCAN cursor MATCH pattern | kv_scan | Prefix-only; * suffix supported. |
KEYS pattern | kv_scan (drained) | Avoid in production — scans the whole keyspace. |
Lists → Queues
| Redis | Flo opcode | Notes |
|---|---|---|
LPUSH queue value | queue_enqueue | |
RPOP queue | queue_dequeue | Single-message dequeue. |
BRPOP queue timeout | queue_dequeue + block_ms | Long-poll. |
Flo queues are leased / acked, not auto-removed. After RPOP, the message is held under a lease until ack/nack/expiry. See Queues.
Streams
| Redis | Flo opcode | Notes |
|---|---|---|
XADD stream * field value | stream_append | |
XREAD COUNT n STREAMS stream id | stream_read | |
XLEN stream | stream_info |
Optimistic concurrency: WATCH/MULTI/EXEC
Flo does not implement multi-key transactions. The WATCH/MULTI/EXEC pattern translates idiomatically to Flo's CAS:
# Redis
WATCH counter
val = GET counter
MULTI
SET counter (val+1)
EXEC
# Flo equivalent (single Raft entry, no coordinator)
r = kv.get("counter") # returns value + version
kv.put("counter", new_val,
cas_version = r.version) # fails with Conflict if version movedFor atomic increments specifically, prefer INCR / kv.incr — it's unconditional and never conflicts.
Differences from Redis
| Area | Behavior |
|---|---|
| Persistence | Every write is Raft-replicated and committed to UAL before responding. There is no SAVE/BGSAVE — Flo is always durable. |
| Eviction | No maxmemory LRU eviction. Out-of-memory rejects new writes; configure TTLs explicitly. |
| Pub/Sub | Not supported via RESP. Use Streams or Streaming Updates. |
| Lua scripting | EVAL/EVALSHA not supported. Use Stream Processing for server-side logic. |
| Cluster slots | CLUSTER commands return a single-slot response. Flo's partitioning is internal and works without client awareness. |
| Transactions | MULTI/EXEC returns an error. Use CAS or model multi-field state as a single JSON document. |
OBJECT ENCODING etc. | Not supported. |
Connecting
# redis-cli
redis-cli -h flo.example.com -p 9000
127.0.0.1:9000> SET hello world
OK
127.0.0.1:9000> INCR counter
(integer) 1
127.0.0.1:9000> JSON.SET order:42 $ '{"items":3,"status":"new"}'
OK
127.0.0.1:9000> JSON.SET order:42 $.status '"shipped"'
OK
127.0.0.1:9000> JSON.GET order:42 $.status
"\"shipped\""Any RESP client library should connect with the same host/port settings you'd give a Redis instance. There is no AUTH negotiation today — see Security for transport-level options.