object_store/
layers.rs

1// Copyright 2023 Greptime Team
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15mod lru_cache;
16
17pub use lru_cache::*;
18pub use opendal::layers::*;
19pub use prometheus::build_prometheus_metrics_layer;
20
21mod prometheus {
22    use std::sync::{Mutex, OnceLock};
23
24    use opendal::layers::PrometheusLayer;
25
26    static PROMETHEUS_LAYER: OnceLock<Mutex<PrometheusLayer>> = OnceLock::new();
27
28    /// This logical tries to extract parent path from the object storage operation
29    /// the function also relies on assumption that the region path is built from
30    /// pattern `<data|index>/catalog/schema/table_id/...` OR `greptimedb/object_cache/<read|write>/...`
31    ///
32    /// We'll get the data/catalog/schema from path.
33    pub fn build_prometheus_metrics_layer(_with_path_label: bool) -> PrometheusLayer {
34        PROMETHEUS_LAYER
35            .get_or_init(|| {
36                // let path_level = if with_path_label { 3 } else { 0 };
37
38                // opendal doesn't support dynamic path label trim
39                // we have uuid in index path, which causes the label size to explode
40                // remove path label first, waiting for later fix
41                // TODO(shuiyisong): add dynamic path label trim for opendal
42
43                let layer = PrometheusLayer::builder()
44                    .path_label(0)
45                    .register_default()
46                    .unwrap();
47
48                Mutex::new(layer)
49            })
50            .lock()
51            .unwrap()
52            .clone()
53    }
54}