defmodule Mongo.Ecto do
@moduledoc """
Ecto integration with MongoDB.
This document will present a general overview of using MongoDB with Ecto,
including common pitfalls and extra functionalities.
Check the [Ecto documentation](http://hexdocs.pm/ecto) for an introduction or
[examples/simple](https://github.com/ankhers/mongodb_ecto/tree/master/examples/simple)
for a sample application using Ecto and MongoDB.
## Repositories
The first step to use MongoDB with Ecto is to define a repository with
`Mongo.Ecto` as an adapter. First define a module:
defmodule Repo do
use Ecto.Repo, otp_app: :my_app
end
Then configure it your application environment, usually in your
`config/config.exs`:
config :my_app, Repo,
adapter: Mongo.Ecto,
database: "ecto_simple",
username: "mongodb",
password: "mongodb",
hostname: "localhost"
config :my_app,
# Add Repo to this list so you can run commands like `mix ecto.create`.
ecto_repos: [Repo]
For more connection options, see mongodb-driver's [Mongo.start_link](https://hexdocs.pm/mongodb_driver/1.5.2/Mongo.html#start_link/1). Note that to use a connection string (mongodb:// or mongodb+srv://), you must set `mongo_url: ` instead of `url: `.
Each repository in Ecto defines a `start_link/0` function that needs to be
invoked before using the repository. This function is generally from your
supervision tree:
def start(_type, _args) do
import Supervisor.Spec
children = [
worker(Repo, [])
]
opts = [strategy: :one_for_one, name: MyApp.Supervisor]
Supervisor.start_link(children, opts)
end
## Models
With the repository defined, we can define our models:
defmodule Weather do
use Ecto.Model
# see the note below for explanation of this line
@primary_key {:id, :binary_id, autogenerate: true}
# weather is the MongoDB collection name
schema "weather" do
field :city, :string
field :temp_lo, :integer
field :temp_hi, :integer
field :prcp, :float, default: 0.0
end
end
Ecto defaults to using `:id` type for primary keys, that is translated to
`:integer` for SQL databases, and is not handled by MongoDB. You need to
specify the primary key to use the `:binary_id` type, that the adapter will
translate to ObjectID. Remember to place this declaration before the `schema`
call.
The name of the primary key is just a convenience, as MongoDB forces us to use
`_id`. Every other name will be recursively changed to `_id` in all calls to
the adapter. We propose to use `id` or `_id` as your primary key name to limit
eventual confusion, but you are free to use whatever you like. Using the
`autogenerate: true` option will tell the adapter to take care of generating
new ObjectIDs. Otherwise you need to do this yourself.
Since setting `@primary_key` for every model can be too repetitive, we
recommend you to define your own module that properly configures it:
defmodule MyApp.Model do
defmacro __using__(_) do
quote do
use Ecto.Model
@primary_key {:id, :binary_id, autogenerate: true}
@foreign_key_type :binary_id # For associations
end
end
end
Now, instead of `use Ecto.Model`, you can `use MyApp.Model` in your modules.
All Ecto types, except `:decimal`, are supported by `Mongo.Ecto`.
By defining a schema, Ecto automatically defines a struct with the schema
fields:
iex> weather = %Weather{temp_lo: 30}
iex> weather.temp_lo
30
The schema also allows the model to interact with a repository:
iex> weather = %Weather{temp_lo: 0, temp_hi: 23}
iex> Repo.insert!(weather)
%Weather{...}
After persisting `weather` to the database, it will return a new copy of
`%Weather{}` with the primary key (the `id`) set. We can use this value to
read a struct back from the repository:
# Get the struct back
iex> weather = Repo.get Weather, "507f191e810c19729de860ea"
%Weather{id: "507f191e810c19729de860ea", ...}
# Update it
iex> weather = %{weather | temp_lo: 10}
iex> Repo.update!(weather)
%Weather{...}
# Delete it
iex> Repo.delete!(weather)
%Weather{...}
## Queries
`Mongo.Ecto` also supports writing queries in Elixir to interact with your
MongoDB. Let's see an example:
import Ecto.Query, only: [from: 2]
query = from w in Weather,
where: w.prcp > 0 or is_nil(w.prcp),
select: w
# Returns %Weather{} structs matching the query
Repo.all(query)
Queries are defined and extended with the `from` macro. The supported keywords
in MongoDB are:
* `:where`
* `:order_by`
* `:offset`
* `:limit`
* `:select`
* `:preload`
When writing a query, you are inside Ecto's query syntax. In order to access
params values or invoke functions, you need to use the `^` operator, which is
overloaded by Ecto:
def min_prcp(min) do
from w in Weather, where: w.prcp > ^min or is_nil(w.prcp)
end
Besides `Repo.all/1`, which returns all entries, repositories also provide
`Repo.one/1`, which returns one entry or nil, and `Repo.one!/1` which returns
one entry or raises.
There is also support for count function in queries that uses `MongoDB`'s
`count` command. Please note that unlike in SQL databases you can only select
a count - there is no support for querying using a count, there is also no
support for counting documents and selecting them at the same time.
Please note that not all Ecto queries are valid MongoDB queries. The adapter
will raise `Ecto.QueryError` if it encounters one, and will try to be as
specific as possible as to what exactly is causing the problem.
For things that are not possible to express with Elixir's syntax in queries,
you can use keyword fragments:
from p in Post, where: fragment(key:["$exists": true]), select: p
To ease of using in more advanced queries, there is `Mongo.Ecto.Helpers`
module you could import into modules dealing with queries. Please see the
documentation of the `Mongo.Ecto.Helpers` module for more information and
supported options.
### Options for reader functions (`Repo.all/2`, `Repo.one/2`, etc)
Such functions also accept options when invoked which allow you to use
parameters specific to MongoDB `find` function:
* `:slave_ok` - the read operation may run on secondary replica set member
* `:partial` - partial data from a query against a sharded cluster in which
some shards do not respond will be returned in stead of raising error
### Upserts
MongoDB's upsert featureset is not as rich as that found in other databases,
and therefore not all features provided for by Ecto are supported.
Some upsert operations can be achieved with multiple database calls and are
therefore unsafe. A warning is printed to the console in these cases. Since
these operations involve multiple DB calls they **cannot be considered safe**
and cannot be recommended. They're intended mostly to make the transition for
Ecto developers coming from another database as clean as possible.
Other operations are completely impossible without jumping through many
database calls and at the time of writing it wasn't deemed worth it to take
this much further. In these cases an error is raised and it's up to you to
pick another strategy. Of course PRs are always welcome!
https://hexdocs.pm/ecto/Ecto.Repo.html#c:insert/2-upserts
## Commands
MongoDB has many administrative commands you can use to manage your database.
We support them through the `Mongo.Ecto.command/2` function.
Mongo.Ecto.command(MyRepo, createUser: "ecto", ...)
We also support one higher level command - `Mongo.Ecto.truncate/1` that is
used to clear the database, i.e. during testing.
Mongo.Ecto.truncate(MyRepo)
You can use it in your `setup` call for cleaning the database before every
test. You can define your own module to use instead of `ExUnit.Case`, so you
don't have to define this each time.
defmodule MyApp.Case do
use ExUnit.CaseTemplate
setup do
Mongo.Ecto.truncate(MyRepo)
:ok
end
end
Please see documentation for those functions for more information.
## Associations
Ecto supports defining associations on schemas:
defmodule Post do
use Ecto.Model
@primary_key {:id, :binary_id, autogenerate: true}
@foreign_key_type :binary_id
schema "posts" do
has_many :comments, Comment
end
end
Keep in mind that Ecto associations are stored in different Mongo collections
and multiple queries may be required for retrieving them.
While `Mongo.Ecto` supports almost all association features in Ecto, keep in
mind that MongoDB does not support joins as used in SQL - it's not possible to
query your associations together with the main model.
Some more elaborate association schemas may force Ecto to use joins in some
queries, that are not supported by MongoDB as well. One such call is
`Ecto.Model.assoc/2` function with a `has_many :through` association.
You can find more information about defining associations and each respective
association module in `Ecto.Schema` docs.
## Embedded models
Ecto supports defining relations using embedding models directly inside the
parent model, and that fits MongoDB's design perfectly.
defmodule Post do
#...
schema "posts" do
embeds_many :comments, Comment
end
end
defmodule Comment do
embedded_schema do
field :body, :string
end
end
You can find more information about defining embedded models in the
`Ecto.Schema` docs.
## Indexes and Migrations
Although schema migrations make no sense for databases such as MongoDB there
is one field where they can be very beneficial - indexes. Because of this
Mongodb.Ecto supports Ecto's database migrations. You can generate a migration
with:
$ mix ecto.gen.migration create_posts
This will create a new file inside `priv/repo/migrations` with the `up` and
`down` functions. Check `Ecto.Migration` for more information.
Because MongoDB does not support (or need) database schemas majority of the
functionality provided by `Ecto.Migration` is not useful when working with
MongoDB. As we've already noted the most useful part is indexing, but there
are others - creating capped collections, executing administrative commands,
or migrating data, e.g.:
defmodule SampleMigration do
use Ecto.Migration
def up do
create table(:my_table, options: [capped: true, size: 1024])
create index(:my_table, [:value])
create unique_index(:my_table, [:unique_value])
execute touch: "my_table", data: true, index: true
end
def down do
# ...
end
end
MongoDB adapter does not support `create_if_not_exists` or `drop_if_exists`
migration functions.
## MongoDB adapter features
The adapter uses `mongodb` for communicating with the database and a pooling
library such as `poolboy` for managing connections.
The adapter has support for:
* documents with ObjectID as their primary key
* insert, find, update, remove and count mongo functions
* management commands with `command/2`
* embedded documents either with `:map` type, or embedded models
* partial updates using `change_map/2` and `change_array/2` from the
`Mongo.Ecto.Helpers` module
* queries using javascript expression and regexes using respectively
`javascript/2` and `regex/2` functions from `Mongo.Ecto.Helpers` module.
### MongoDB adapter options
Options passed to the adapter are split into different categories decscribed
below. All options should be given via the repository configuration.
### Compile time options
Those options should be set in the config file and require recompilation in
order to make an effect.
* `:adapter` - The adapter name, in this case, `Mongo.Ecto`
* `:pool` - The connection pool module, defaults to `Mongo.Pool.Poolboy`
* `:log_level` - The level to use when logging queries (default: `:debug`)
### Connection options
* `:hostname` - Server hostname (default: `localhost`)
* `:port` - Server port (default: `27017`)
* `:username` - Username
* `:password` - User password
* `:mongo_url` - A MongoDB
[URL](https://docs.mongodb.com/manual/reference/connection-string/)
* `:connect_timeout` - The timeout for establishing new connections
(default: 5000)
* `:w` - MongoDB's write convern (default: 1). If set to 0, some of the
Ecto's functions may not work properely
* `:j`, `:fsync`, `:wtimeout` - Other MongoDB's write concern options.
Please consult MongoDB's documentation
### Pool options
`Mongo.Ecto` does not use Ecto pools, instead pools provided by the MongoDB
driver are used. The default poolboy adapter accepts following options:
* `:pool_size` - The number of connections to keep in the pool (default: 10)
* `:max_overflow` - The maximum overflow of connections (default: 0)
For other adapters, please see their documentation.
"""
@behaviour Ecto.Adapter
@behaviour Ecto.Adapter.Storage
@behaviour Ecto.Adapter.Schema
@behaviour Ecto.Adapter.Queryable
alias Mongo.Ecto.Connection
alias Mongo.Ecto.Conversions
alias Mongo.Ecto.NormalizedQuery
alias Mongo.Ecto.NormalizedQuery.{
AggregateQuery,
CountQuery,
ReadQuery,
WriteQuery
}
## Adapter
@doc false
@impl true
defmacro __before_compile__(_env) do
end
@doc false
def application, do: :mongodb_ecto
@pool_opts [:timeout, :pool, :pool_size, :migration_lock] ++
[:queue_target, :queue_interval, :ownership_timeout]
@impl true
def init(config) do
connection = Connection
unless Code.ensure_loaded?(connection) do
driver = :mongodb_driver
raise """
Could not find #{inspect(connection)}.
Please verify you have added #{inspect(driver)} as a dependency to mix.exs:
{#{inspect(driver)}, ">= 0.0.0"}
Remember to recompile Ecto afterwards by cleaning the current build:
mix deps.clean --build ecto
"""
end
log = Keyword.get(config, :log, :debug)
telemetry_prefix = Keyword.fetch!(config, :telemetry_prefix)
telemetry = {config[:repo], log, telemetry_prefix ++ [:query]}
opts = Keyword.take(config, @pool_opts)
meta = %{telemetry: telemetry, opts: opts}
{:ok, connection.child_spec(config), meta}
end
@impl true
def ensure_all_started(_repo, type) do
{:ok, _mongo} = Application.ensure_all_started(:mongodb_driver, type)
end
@impl true
def loaders(:time, type), do: [&load_time/1, type]
def loaders(:date, type), do: [&load_date/1, type]
def loaders(:utc_datetime, type), do: [&load_datetime/1, type]
def loaders(:utc_datetime_usec, type), do: [&load_datetime/1, type]
def loaders(:naive_datetime, type), do: [&load_datetime/1, type]
def loaders(:naive_datetime_usec, type), do: [&load_datetime/1, type]
def loaders(:binary_id, type), do: [&load_objectid/1, type]
def loaders(:uuid, type), do: [&load_binary/1, type]
def loaders(:binary, type), do: [&load_binary/1, type]
def loaders(:integer, type), do: [&load_integer/1, type]
def loaders(_base, type) do
[type]
end
defp load_time(time), do: time
defp load_date(nil) do
{:ok, nil}
end
defp load_date(date) do
{:ok, date |> DateTime.to_date()}
end
defp load_datetime(datetime) do
{:ok, datetime}
end
defp load_integer(map) do
{:ok, map}
end
defp load_binary(%BSON.Binary{binary: binary}), do: {:ok, binary}
defp load_binary(nil), do: {:ok, nil}
defp load_binary(_), do: :error
defp load_objectid(%BSON.ObjectId{} = objectid) do
{:ok, BSON.ObjectId.encode!(objectid)}
rescue
ArgumentError ->
:error
end
defp load_objectid(nil), do: {:ok, nil}
defp load_objectid(_arg), do: :error
@impl true
def dumpers(:time, type), do: [type, &dump_time/1]
def dumpers(:date, type), do: [type, &dump_date/1]
def dumpers(:utc_datetime, type), do: [type, &dump_utc_datetime/1]
def dumpers(:utc_datetime_usec, type), do: [type, &dump_utc_datetime/1]
def dumpers(:naive_datetime, type), do: [type, &dump_naive_datetime/1]
def dumpers(:naive_datetime_usec, type), do: [type, &dump_naive_datetime/1]
def dumpers(:binary_id, type), do: [type, &dump_objectid/1]
def dumpers(:uuid, type), do: [type, &dump_binary(&1, :uuid)]
def dumpers(:binary, type), do: [type, &dump_binary(&1, :generic)]
def dumpers(_base, type), do: [type]
defp dump_time({h, m, s, _}), do: Time.from_erl({h, m, s})
defp dump_time(%Time{} = time), do: time
defp dump_time(_), do: :error
defp dump_date({_, _, _} = date) do
dt =
{date, {0, 0, 0}}
|> NaiveDateTime.from_erl!()
|> DateTime.from_naive!("Etc/UTC")
{:ok, dt}
end
defp dump_date(%Date{} = date) do
dt =
{Date.to_erl(date), {0, 0, 0}}
|> NaiveDateTime.from_erl!()
|> DateTime.from_naive!("Etc/UTC")
{:ok, dt}
end
defp dump_date(nil), do: {:ok, nil}
defp dump_date(_) do
:error
end
defp dump_utc_datetime({{_, _, _} = date, {h, m, s, ms}}) do
datetime =
{date, {h, m, s}}
|> NaiveDateTime.from_erl!({ms, 6})
|> DateTime.from_naive!("Etc/UTC")
{:ok, datetime}
end
defp dump_utc_datetime({{_, _, _} = date, {h, m, s}}) do
datetime =
{date, {h, m, s}}
|> NaiveDateTime.from_erl!({0, 6})
|> DateTime.from_naive!("Etc/UTC")
{:ok, datetime}
end
defp dump_utc_datetime(datetime) do
{:ok, datetime}
end
defp dump_naive_datetime({{_, _, _} = date, {h, m, s, ms}}) do
datetime =
{date, {h, m, s}}
|> NaiveDateTime.from_erl!({ms, 6})
|> DateTime.from_naive!("Etc/UTC")
{:ok, datetime}
end
defp dump_naive_datetime(%NaiveDateTime{} = dt) do
datetime =
dt
|> DateTime.from_naive!("Etc/UTC")
{:ok, datetime}
end
defp dump_naive_datetime(dt) do
datetime =
dt
|> DateTime.from_naive!("Etc/UTC")
{:ok, datetime}
end
defp dump_binary(binary, subtype) when is_binary(binary),
do: {:ok, %BSON.Binary{binary: binary, subtype: subtype}}
defp dump_binary(nil, _), do: {:ok, nil}
defp dump_binary(_, _), do: :error
defp dump_objectid(<<objectid::binary-size(24)>>) do
{:ok, BSON.ObjectId.decode!(objectid)}
rescue
ArgumentError -> :error
end
defp dump_objectid(nil), do: {:ok, nil}
defp dump_objectid(_), do: :error
@impl Ecto.Adapter.Schema
def autogenerate(:id), do: raise("MongoDB adapter does not support `:id` type as primary key")
def autogenerate(:embed_id), do: BSON.ObjectId.encode!(Mongo.object_id())
# :binary_id is expected to be generated by Mongo itself as a BSON.ObjectId
def autogenerate(:binary_id), do: nil
@impl Ecto.Adapter.Queryable
def prepare(function, query) do
{:nocache, {function, query}}
end
@read_queries [ReadQuery, CountQuery, AggregateQuery]
@impl Ecto.Adapter.Queryable
def execute(meta, _query_meta, {:nocache, {function, query}}, params, opts) do
struct = get_struct_from_query(query)
case apply(NormalizedQuery, function, [query, params]) do
%AggregateQuery{} = query ->
{rows, count} =
Connection.read(meta, query, opts)
|> Enum.map_reduce(0, &{[&1["value"]], &2 + 1})
{count, rows}
%CountQuery{} = query ->
{rows, count} =
Connection.read(meta, query, opts)
|> Enum.map_reduce(0, &{[&1["value"]], &2 + 1})
{count, rows}
%ReadQuery{} = query ->
{rows, count} =
Connection.read(meta, query, opts)
|> Enum.map_reduce(0, &{process_document(&1, query, struct), &2 + 1})
{count, rows}
%WriteQuery{} = write ->
result = apply(Connection, function, [meta, write, opts])
{result, nil}
end
end
def row_to_list(row, %{select: %{from: {_op, {_source, _tuple, _something, types}}}}) do
Enum.map(types, fn {field, _type} ->
case field do
:id -> row["_id"]
_ -> row[Atom.to_string(field)]
end
end)
end
def row_to_list(row, %{select: %{from: :none}}) do
[row]
end
# This can be backed by a normal mongo stream, we just have to get it to play nicely with
# ecto's batch/preload functionality ( hence the map(&{nil, [&1]}) )
@impl Ecto.Adapter.Queryable
def stream(adapter_meta, _query_meta, {:nocache, {function, query}}, params, opts) do
struct = get_struct_from_query(query)
case apply(NormalizedQuery, function, [query, params]) do
%{__struct__: read} = query when read in @read_queries ->
Connection.read(adapter_meta, query, opts)
|> Stream.map(&process_document(&1, query, struct))
%WriteQuery{} = write ->
apply(Connection, function, [adapter_meta, write, opts])
[nil]
end
|> Stream.map(&{nil, [&1]})
end
defp get_struct_from_query(%Ecto.Query{from: %Ecto.Query.FromExpr{source: {_coll, nil}}}),
do: nil
defp get_struct_from_query(%Ecto.Query{from: %Ecto.Query.FromExpr{source: {_coll, struct}}}),
do: struct.__struct__()
defp get_struct_from_query(_), do: nil
@impl Ecto.Adapter.Schema
def insert(adapter_meta, schema_meta, fields, on_conflict, returning, opts) do
normalized_query = NormalizedQuery.insert(schema_meta, fields, on_conflict, returning, opts)
# IO.inspect(normalized_query, label: "normalized_query")
apply(Connection, normalized_query.op, [adapter_meta, normalized_query, opts])
end
@impl Ecto.Adapter.Schema
def insert_all(
adapter_meta,
schema_meta,
_header,
fields_list,
on_conflict,
returning,
_placeholders,
opts
) do
normalized_query =
NormalizedQuery.insert(schema_meta, fields_list, on_conflict, returning, opts)
# IO.inspect(normalized_query, label: "normalized_query")
apply(Connection, normalized_query.op, [adapter_meta, normalized_query, opts])
end
@impl Ecto.Adapter.Schema
def update(repo, meta, fields, filters, _returning, opts) do
{repo, meta, fields, filters, opts}
normalized = NormalizedQuery.update_one(meta, fields, filters)
Connection.update_one(repo, normalized, opts)
end
@impl true
def delete(repo, meta, filter, _remaining, opts) do
normalized = NormalizedQuery.delete(meta, filter)
Connection.delete(repo, normalized, opts)
end
defp process_document(document, %{fields: fields, pk: pk}, struct) do
document = Conversions.to_ecto_pk(document, pk || :_id)
Enum.map(fields, fn
{:field, name, _field} ->
# If we don't have the key but do a have a struct, we get the default.
# Otherwise, we get get the value from the doc
if Map.has_key?(document, Atom.to_string(name)) == false && struct != nil do
Map.get(struct, name)
else
Map.get(document, Atom.to_string(name))
end
{:value, value, _field} ->
Conversions.to_ecto_pk(value, pk)
_field ->
document
end)
end
# TODO Not sure how to do this or if it's useful for Mongo
@impl true
def checkout(_, _, fun) do
fun.()
end
@impl true
def checked_out?(_) do
false
end
## Storage
# Noop for MongoDB, as any databases and collections are created as needed.
@impl true
def storage_up(_opts) do
:ok
end
@impl true
def storage_down(opts) do
Connection.storage_down(opts)
end
@impl true
def storage_status(opts) do
Connection.storage_status(opts)
end
## Mongo specific calls
special_regex = %BSON.Regex{pattern: "\\.system|\\$", options: ""}
# migration_regex = %BSON.Regex{pattern: @migration, options: ""}
@list_collections_query [name: ["$not": special_regex]]
@doc """
Drops all the collections in current database.
Skips system collections and `schema_migrations` collection.
Especially useful in testing.
Returns list of dropped collections.
"""
@spec truncate(Ecto.Repo.t(), Keyword.t()) :: [String.t()]
def truncate(repo, opts \\ []) do
opts = Keyword.put(opts, :log, false)
version = db_version(repo)
[major_version, minor_version | _] = version
collection_names =
if major_version > 3 || (major_version == 3 && minor_version >= 4) do
_all_collection_names =
repo
|> command([listCollections: 1], opts)
|> get_in(["cursor", "firstBatch"])
# exclude mongo views which were introduced in version 3.4
|> Enum.filter(&(&1["type"] == "collection"))
|> Enum.map(&Map.fetch!(&1, "name"))
|> Enum.reject(&String.contains?(&1, "system."))
# all_collection_names -- [@migration]
else
list_collections(version, repo, opts)
end
Enum.map(collection_names, fn collection ->
truncate_collection(repo, collection, opts)
collection
end)
end
@doc """
Runs a command in the database.
## Usage
Mongo.Ecto.command(Repo, drop: "collection")
## Options
* `:database` - run command against a specific database
(default: repo's database)
* `:log` - should command queries be logged (default: true)
For list of available commands please see: http://docs.mongodb.org/manual/reference/command/
"""
@spec command(Ecto.Repo.t(), BSON.document(), Keyword.t()) :: BSON.document()
def command(repo, command, opts \\ []) do
normalized = NormalizedQuery.command(command, opts)
Connection.command(Ecto.Adapter.lookup_meta(repo), normalized, opts)
end
@doc false
def list_collections(repo, opts \\ []) do
list_collections(db_version(repo), repo, opts)
end
defp list_collections([major_version | _], repo, opts) when major_version >= 3 do
colls = command(repo, [listCollections: 1], opts)["cursor"]["firstBatch"]
_all_collections =
colls
|> Enum.map(&Map.fetch!(&1, "name"))
|> Enum.reject(&String.contains?(&1, "system."))
# all_collections -- [@migration]
end
defp list_collections(_, repo, opts) do
query = %ReadQuery{coll: "system.namespaces", query: @list_collections_query}
opts = Keyword.put(opts, :log, false)
Connection.read(Ecto.Adapter.lookup_meta(repo), query, opts)
|> Enum.map(&Map.fetch!(&1, "name"))
|> Enum.map(fn collection ->
collection |> String.split(".", parts: 2) |> Enum.at(1)
end)
end
defp truncate_collection(repo, collection, opts) do
meta = Ecto.Adapter.lookup_meta(repo)
query = %WriteQuery{coll: collection, query: %{}}
Connection.delete_all(meta, query, opts)
end
defp db_version(repo) do
command(repo, [buildinfo: 1], [])["versionArray"]
end
@doc """
Lists indexes in the specified `repo` and `collection`.
"""
def list_indexes(repo, collection, opts \\ []) do
Ecto.Adapter.lookup_meta(repo)
|> Connection.query(:list_indexes, [collection], opts)
|> Enum.to_list()
end
def list_index_names(repo, collection, opts \\ []) do
Ecto.Adapter.lookup_meta(repo)
|> Connection.query(:list_index_names, [collection], opts)
|> Enum.to_list()
end
def index(repo, collection, index_name, opts \\ []) do
list_indexes(repo, collection, opts)
|> Enum.find(fn index -> index["name"] == index_name end)
end
@doc """
Creates one or more `indexes` for the specified collection `coll`.
See
https://docs.mongodb.com/manual/reference/method/db.collection.createIndexes/#mongodb-method-db.collection.createIndexes
for the syntax of `indexes`.
"""
def create_indexes(repo, collection, indexes, opts \\ []) do
Ecto.Adapter.lookup_meta(repo)
|> Connection.query(:create_indexes, [collection, indexes], opts)
end
@doc """
Drops the specified `indexes` in the collection `coll`.
To drop a single index, pass the name of the index.
To drop multiple indexes at once pass a list of indexes to `index`. To drop all indexes except
that of `_id` pass "*" to `index`.
See https://docs.mongodb.com/manual/reference/command/dropIndexes/#dropindexes
"""
def drop_indexes(repo, collection, indexes, opts \\ []) do
Ecto.Adapter.lookup_meta(repo)
|> Connection.query(:drop_index, [collection, indexes], opts)
end
end
