mungo (formerly gleam_mongo)

mungo: a felted fabric made from the shredded fibre of repurposed woollen cloth

A mongodb driver for gleam

Quick start

gleam shell # Run an Erlang shell

Installation

gleam add mungo

Roadmap

• support basic mongodb commands
• support aggregation
• support connection strings
• support authentication
• support mongodb cursors
• support connection pooling
• support bulk operations
• support clusters
• support tls
• support transactions
• support change streams
• support other mongodb commands

Usage

import gleam/uri
import gleam/option
import mungo
import mungo/crud.{Sort, Upsert}
import mungo/aggregation.{
 Let, add_fields, aggregate, match, pipelined_lookup, to_cursor, unwind,
}
import bison/bson

pub fn main() {
 let assert Ok(client) =
   mungo.start(
     "mongodb://app-dev:passwd@localhost/app-db?authSource=admin",
     1024
   )

 let assert Ok(users) =
   client
   |> mungo.collection("users")

 let _ =
   users
   |> mungo.insert_many([
     [
       #("username", bson.Str("jmorrow")),
       #("name", bson.Str("vincent freeman")),
       #("email", bson.Str("jmorrow@gattaca.eu")),
       #("age", bson.Int32(32)),
     ],
     [
       #("username", bson.Str("real-jerome")),
       #("name", bson.Str("jerome eugene morrow")),
       #("email", bson.Str("real-jerome@running.at")),
       #("age", bson.Int32(32)),
     ],
   ])

 let _ =
   users
   |> mungo.update_one(
     [#("username", bson.Str("real-jerome"))],
     [
       #(
         "$set",
         bson.Document([
           #("username", bson.Str("eugene")),
           #("email", bson.Str("eugene@running.at ")),
         ]),
       ),
     ],
     [Upsert],
   )

 let assert Ok(yahoo_cursor) =
   users
   |> mungo.find_many(
     [#("email", bson.Regex(#("yahoo", "")))],
     [Sort([#("username", bson.Int32(-1))])],
   )
 let _yahoo_users = mungo.to_list(yahoo_cursor)

 let assert Ok(underage_lindsey_cursor) =
   users
   |> aggregate([Let([#("minimum_age", bson.Int32(21))])])
   |> match([
     #(
       "$expr",
       bson.Document([
         #("$lt", bson.Array([bson.Str("$age"), bson.Str("$$minimum_age")])),
       ]),
     ),
   ])
   |> add_fields([
     #(
       "first_name",
       bson.Document([
         #(
           "$arrayElemAt",
           bson.Array([
             bson.Document([
               #("$split", bson.Array([bson.Str("$name"), bson.Str(" ")])),
             ]),
             bson.Int32(0),
           ]),
         ),
       ]),
     ),
   ])
   |> match([#("first_name", bson.Str("lindsey"))])
   |> pipelined_lookup(
     from: "profiles",
     define: [#("user", bson.Str("$username"))],
     pipeline: [
       [
         #(
           "$match",
           bson.Document([
             #(
               "$expr",
               bson.Document([
                 #(
                   "$eq",
                   bson.Array([bson.Str("$username"), bson.Str("$$user")]),
                 ),
               ]),
             ),
           ]),
         ),
       ],
     ],
     alias: "profile",
   )
   |> unwind("$profile", False)
   |> to_cursor

 let assert #(option.Some(_underage_lindsey), underage_lindsey_cursor) =
   underage_lindsey_cursor
   |> mungo.next

 let assert #(option.None, _) =
   underage_lindsey_cursor
   |> mungo.next
}