# glitr_convert_cake
[](https://hex.pm/packages/glitr_convert_cake)
[](https://hexdocs.pm/glitr_convert_cake/)
**Easily select, insert, update and decode values from a database using cake and glitr_convert**
## Installation
```sh
gleam add glitr_convert_cake
```
## Usage
```gleam
import cake
import cake/dialect/postgres_dialect
import cake/insert as i
import cake/param
import cake/select as s
import cake/update as u
import cake/where as w
import gleam/io
import gleam/pgo
import gleam/result
import glitr/convert as c
import glitr/convert/cake as cc
pub type User {
User(id: String, name: String, age: Int)
}
pub fn user_converter() -> c.Converter(User) {
c.object({
use id <- c.parameter
use name <- c.parameter
use age <- c.parameter
use <- c.constructor
User(id:, name:, age:)
})
|> c.field("id", fn(v) { Ok(v.id) }, c.string())
|> c.field("name", fn(v) { Ok(v.name) }, c.string())
|> c.field("age", fn(v) { Ok(v.age) }, c.int())
|> c.to_converter
}
pub fn main() {
let alice = User("1", "Alice", 21)
let bob = User("2", "Bob", 22)
let table_name = "users"
let create_query = i.new()
|> i.table(table_name)
|> cc.cake_insert(user_converter(), [alice, bob])
|> i.to_query
// Execute query
let update_query = u.new()
|> u.table(table_name)
|> cc.cake_update(user_converter(), User(..alice, age: 36))
|> u.where(w.col("id") |> w.eq(w.string(alice.id)))
|> u.to_query
// Execute query
let select_all_query = s.new()
|> s.from_table(table_name)
|> cc.cake_select_fields(user_converter())
|> s.to_query
// Example: executing query with pgo and decoding the values with glitr_convert_cake
let query = select_all_query |> postgres_dialect.read_query_to_prepared_statement
pgo.execute(
query |> cake.get_sql,
db_connection, // Connection to a Postgres DB
query |> cake.get_params |> list.map(map_param),
cc.cake_decode(user_converter())
)
|> result.map(fn (res) { res.rows })
|> io.debug
// Ok(List(User("1", "Alice", 36), User("2", "Bob", 22)))
}
fn map_param(p: param.Param) -> pgo.Value {
case p {
param.BoolParam(v) -> pgo.bool(v)
param.FloatParam(v) -> pgo.float(v)
param.IntParam(v) -> pgo.int(v)
param.StringParam(v) -> pgo.text(v)
param.NullParam -> pgo.null()
}
}
```
Further documentation can be found at <https://hexdocs.pm/glitr_convert_cake>.
## Development
```sh
gleam run # Run the project
gleam test # Run the tests
```
