pleroma/lib/pleroma/repo.ex
Mark Felder 66cb3294ed Switch to PromEx for prometheus metrics
Recommending use of the separate HTTP server for exposing the metrics
and securing it externally on your firewall or reverse proxy. It will
listen on port 4021 by default.
2023-11-13 15:34:59 -05:00

96 lines
2.7 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Repo do
use Ecto.Repo,
otp_app: :pleroma,
adapter: Ecto.Adapters.Postgres,
migration_timestamps: [type: :naive_datetime_usec]
import Ecto.Query
require Logger
@doc """
Dynamically loads the repository url from the
DATABASE_URL environment variable.
"""
def init(_, opts) do
{:ok, Keyword.put(opts, :url, System.get_env("DATABASE_URL"))}
end
@doc "find resource based on prepared query"
@spec find_resource(Ecto.Query.t()) :: {:ok, struct()} | {:error, :not_found}
def find_resource(%Ecto.Query{} = query) do
case __MODULE__.one(query) do
nil -> {:error, :not_found}
resource -> {:ok, resource}
end
end
def find_resource(_query), do: {:error, :not_found}
@doc """
Gets association from cache or loads if need
## Examples
iex> Repo.get_assoc(token, :user)
%User{}
"""
@spec get_assoc(struct(), atom()) :: {:ok, struct()} | {:error, :not_found}
def get_assoc(resource, association) do
case __MODULE__.preload(resource, association) do
%{^association => assoc} when not is_nil(assoc) -> {:ok, assoc}
_ -> {:error, :not_found}
end
end
@doc """
Returns a lazy enumerable that emits all entries from the data store matching the given query.
`returns_as` use to group records. use the `batches` option to fetch records in bulk.
## Examples
# fetch records one-by-one
iex> Pleroma.Repo.chunk_stream(Pleroma.Activity.Queries.by_actor(ap_id), 500)
# fetch records in bulk
iex> Pleroma.Repo.chunk_stream(Pleroma.Activity.Queries.by_actor(ap_id), 500, :batches)
"""
@spec chunk_stream(Ecto.Query.t(), integer(), atom()) :: Enumerable.t()
def chunk_stream(query, chunk_size, returns_as \\ :one, query_options \\ []) do
# We don't actually need start and end functions of resource streaming,
# but it seems to be the only way to not fetch records one-by-one and
# have individual records be the elements of the stream, instead of
# lists of records
Stream.resource(
fn -> 0 end,
fn
last_id ->
query
|> order_by(asc: :id)
|> where([r], r.id > ^last_id)
|> limit(^chunk_size)
|> all(query_options)
|> case do
[] ->
{:halt, last_id}
records ->
last_id = List.last(records).id
if returns_as == :one do
{records, last_id}
else
{[records], last_id}
end
end
end,
fn _ -> :ok end
)
end
end