maplibre/io/
source_client.rs

1//! HTTP client.
2
3use async_trait::async_trait;
4use thiserror::Error;
5
6use crate::{coords::WorldTileCoords, io::source_type::SourceType};
7
8/// A closure that returns a HTTP client.
9pub type HTTPClientFactory<HC> = dyn Fn() -> HC;
10
11/// On the web platform futures are not thread-safe (i.e. not Send). This means we need to tell
12/// async_trait that these bounds should not be placed on the async trait:
13/// [https://github.com/dtolnay/async-trait/blob/b70720c4c1cc0d810b7446efda44f81310ee7bf2/README.md#non-threadsafe-futures](https://github.com/dtolnay/async-trait/blob/b70720c4c1cc0d810b7446efda44f81310ee7bf2/README.md#non-threadsafe-futures)
14///
15/// Users of this library can decide whether futures from the HTTPClient are thread-safe or not via
16/// the future "thread-safe-futures". Tokio futures are thread-safe.
17#[cfg_attr(not(feature = "thread-safe-futures"), async_trait(?Send))]
18#[cfg_attr(feature = "thread-safe-futures", async_trait)]
19pub trait HttpClient: Clone + Sync + Send + 'static {
20    async fn fetch(&self, url: &str) -> Result<Vec<u8>, SourceFetchError>;
21}
22
23/// Gives access to the HTTP client which can be of multiple types,
24/// see [crates::io::source_client::SourceClient]
25#[derive(Clone)]
26pub struct HttpSourceClient<HC>
27where
28    HC: HttpClient,
29{
30    inner_client: HC,
31}
32
33#[derive(Error, Debug)]
34#[error("failed to fetch from source")]
35pub struct SourceFetchError(#[source] pub Box<dyn std::error::Error>);
36
37/// Defines the different types of HTTP clients such as basic HTTP and Mbtiles.
38/// More types might be coming such as S3 and other cloud http clients.
39#[derive(Clone)]
40pub struct SourceClient<HC>
41where
42    HC: HttpClient,
43{
44    http: HttpSourceClient<HC>,
45}
46
47impl<HC> SourceClient<HC>
48where
49    HC: HttpClient,
50{
51    pub fn new(http: HttpSourceClient<HC>) -> Self {
52        Self { http }
53    }
54
55    pub async fn fetch(
56        &self,
57        coords: &WorldTileCoords,
58        source_type: &SourceType,
59    ) -> Result<Vec<u8>, SourceFetchError> {
60        self.http.fetch(coords, source_type).await
61    }
62}
63
64impl<HC> HttpSourceClient<HC>
65where
66    HC: HttpClient,
67{
68    pub fn new(http_client: HC) -> Self {
69        Self {
70            inner_client: http_client,
71        }
72    }
73
74    pub async fn fetch(
75        &self,
76        coords: &WorldTileCoords,
77        source_type: &SourceType,
78    ) -> Result<Vec<u8>, SourceFetchError> {
79        self.inner_client
80            .fetch(source_type.format(coords).as_str())
81            .await
82    }
83}
maplibre/io/source_client.rs

maplibre/io/
source_client.rs
