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import gleam/dynamic
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 _ =
sqlight.exec(
"pragma foreign_keys = off;
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 add_column = fn(name) {
let _ =
sqlight.exec(
"alter table tb_count add column " <> name <> " text;",
connection,
)
Nil
}
add_column("created_at")
add_column("updated_at")
Nil
}
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, ""),
))
Ok([]) -> {
wisp.log_error("Database query returned no rows unexpectedly.")
Error("Unreachable entity")
}
Ok([_, _, ..]) -> {
wisp.log_error("Database query returned multiple rows unexpectedly.")
Error("Unreachable entity")
}
Error(_) -> {
wisp.log_error("Database query failed.")
Error("Database operation failed")
}
}
}
}
}
|