db

Super duper simple, csv-backed tcp key-value store

Database backing http://comments.reillybrothers.net and comments.js

How to start server:

cd server
go run main.go --port 8089 --file /tmp/mydb.csv

How to connect to server:

Command Line

netcat localhost 8089
set,a,b
get,a

Golang client

Library in db.go provides a Client type, which has Get, Set, GetList, and Append methods, which simplify direct TCP access.

Lists and Maps via Extended Grammar

Simple access is permitted via:

Get

get,my key

Set

set,my key, my value

But the database supports list and map storage types as well. Note that all extended commands will always require a top-level key immediately after the command (e.g., get or set), which serves as a namespace for further extended commands. Below, we use the namespace "my top key" for examples.

List Append

set,my top key,+,+,appended value
get,my top key,+,0,appended value

The double + means append the "appended value" to the list structure in "my top key"

Appending is not supported for "get" command, for obvious reasons.

List Modify (or List Indexing)

set,my top key,+,0,changed value
get,my top key,+,0

The + with a following index means change the value at index index (the index is 0 here) to "changed value".

Map Values

set,my top key,->,inner key,inner value
get,my top key,->,inner key

The -> with a following key means change (or set) the keyed value located at key "inner key" to "inner value".

Arbitrary chaining

set,my top key,->,inner key,->,another inner key,+,+,+,+,->,super inner key,super inner value
get,my top key,->,inner key,->,another inner key,+,0,+,0,->,super inner key

Any arbitrary combination of list and map commands may be chained together to create complex storage.

Structured Values

set,my top key,->,inner key,->,another inner key,+,+,+,+,->,super inner key,super inner value
get,my top key,->,inner key,->,another inner key,+,0,+,0,->,super inner key
get,my top key,->,inner key,->,another inner key,+,0,+,0
get,my top key,->,inner key,->,another inner key,+,0
get,my top key,->,inner key,->,another inner key
get,my top key,->,inner key
get,my top key

If a "get" command is underspecified, like get,my top key,->,inner key, then the command will return a JSON-formatted value capturing all sub-structure underneath the underspecified command. The format is:

{
  "V": <stringValue>,
  "L": [
     {
       "V": <stringValue>,
       "L": [...
       "M": {
         "m-key": ...
       }
     }
   ],
   "M": {
     "m-key": {
       "V": <stringValue>,
       ...
     }
   }
}