Protocol Reference

Blink Store uses a line-based text protocol over TCP or Unix sockets.

• One command per line, one response per line.
• Encoding: UTF-8 with \n (LF) line endings.
• Values returned by GET are base64-encoded.

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Commands

Command	Arguments	Description
SET	key value	Store a value. The value is everything after the first space following the key.
GET	key	Retrieve a value. Returns base64-encoded bytes.
DELETE	key	Remove a key.
USAGE	(none)	Return the current memory usage in bytes.
QUIT	(none)	Close the connection gracefully.

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Responses

Response	When
OK	SET succeeded, or DELETE found and removed the key.
VALUE <b64>	GET found the key. <b64> is the base64-encoded value.
NOT_FOUND	GET or DELETE — key does not exist.
USAGE <n>	Current stored size in bytes (keys + values).
ERROR <msg>	Invalid command or internal error. <msg> describes the issue.

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Example session

Below is a complete interaction over a raw TCP connection. Lines starting with > are sent by the client; lines starting with < are responses from the server.

> GET mykey
< NOT_FOUND

> SET mykey hello
< OK

> GET mykey
< VALUE aGVsbG8=

> SET counter 42
< OK

> USAGE
< USAGE 18

> DELETE mykey
< OK

> GET mykey
< NOT_FOUND

> QUIT

Decoding the base64 value: aGVsbG8= → hello.

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Transport

Flag	Transport	Platforms
--tcp <host>:<port>	TCP socket	All
--unix <path>	Unix domain socket	Linux, macOS

The server can listen on TCP, Unix, or both simultaneously.

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Connecting with common tools

netcat:

echo "SET foo bar" | nc 127.0.0.1 8765
echo "GET foo"     | nc 127.0.0.1 8765

Python (one-off):

import socket
s = socket.socket()
s.connect(("127.0.0.1", 8765))
s.sendall(b"SET foo bar\n")
print(s.recv(1024).decode())   # OK
s.sendall(b"GET foo\n")
print(s.recv(1024).decode())   # VALUE YmFy
s.close()

bash /dev/tcp:

exec 3<>/dev/tcp/127.0.0.1/8765
echo "SET foo bar" >&3
read -r reply <&3; echo "$reply"   # OK
exec 3<&-