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import gleam/dynamic
import gleam/list
import gleam/option
import sqlight
import wisp
pub type Counter {
Counter(name: String, num: Int, created_at: String, updated_at: String)
}
pub fn setup(connection) {
let assert Ok(_) =
sqlight.exec(
"create table if not exists tb_count (
id integer primary key autoincrement not null unique,
name text not null unique,
num int not null default (0)
) strict;",
connection,
)
let existing_column_names = existing_columns(connection)
let ensure_column = fn(name) {
case list.contains(existing_column_names, name) {
True -> Nil
False -> {
let assert Ok(_) =
sqlight.exec(
"alter table tb_count add column " <> name <> " text;",
connection,
)
Nil
}
}
}
ensure_column("created_at")
ensure_column("updated_at")
Nil
}
fn existing_columns(connection) -> List(String) {
let assert Ok(columns) =
sqlight.query(
"pragma table_info('tb_count');",
with: [],
on: connection,
expecting: dynamic.element(1, dynamic.string),
)
columns
}
pub fn get_counter(connection, name) {
case name {
"demo" -> Ok(Counter("demo", 1_234_567_890, "", ""))
_ -> {
case
sqlight.query(
"INSERT INTO tb_count (name, created_at, updated_at, num)
VALUES (?1, datetime('now'), datetime('now'), 1)
ON CONFLICT(name) DO UPDATE SET
num = tb_count.num + 1,
updated_at = datetime('now')
RETURNING name, num, created_at, updated_at;",
with: [sqlight.text(name)],
on: connection,
expecting: dynamic.tuple4(
dynamic.string,
dynamic.int,
dynamic.optional(dynamic.string),
dynamic.optional(dynamic.string),
),
)
{
Ok([row]) ->
Ok(Counter(
row.0,
row.1,
option.unwrap(row.2, ""),
option.unwrap(row.3, ""),
))
_ -> {
wisp.log_error("Database query failed or returned unexpected rows.")
Error("Database operation failed")
}
}
}
}
}
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