smr/src/lua/db.lua

--[[
Does most of the database interaction.
Notably, holds a connection to the open sqlite3 database in .conn
]]
local sql = require("lsqlite3")

local queries = require("queries")
local util = require("util")
local config = require("config")

local db = {}
local oldconfigure = configure
db.conn = util.sqlassert(sql.open(config.db))
function configure(...)
	
	--Create sql tables
	assert(db.conn:exec(queries.create_table_authors))
	--Create a fake "anonymous" user, so we don't run into trouble
	--so that no one runs into trouble being able to paste under this account.
	assert(db.conn:exec(queries.insert_anon_author))
	--If/when an author deletes their account, all posts
	--and comments by that author are also deleted (on
	--delete cascade) this is intentional. This also
	--means that all comments by other users on a post
	--an author makes will also be deleted.
	--
	--Post text uses zlib compression
	assert(db.conn:exec(queries.create_table_posts))
	--Store the raw text so people can download it later, maybe
	--we can use it for "download as image" or "download as pdf"
	--in the future too. Stil stored zlib compressed
	assert(db.conn:exec(queries.create_table_raw_text))
	--Maybe we want to store images one day?
	assert(db.conn:exec(queries.create_table_images))
	--Comments on a post
	assert(db.conn:exec(queries.create_table_comments))
	--Tags for a post
	assert(db.conn:exec(queries.create_table_tags))
	--Index for tags
	assert(db.conn:exec(queries.create_index_tags))
	--Store a cookie for logged in users. Logged in users can edit
	--their own posts, and edit their biographies.
	assert(db.conn:exec(queries.create_table_session))

	return oldconfigure(...)
end
configure()

function db.close()
	db.conn:close()
end


return db