First version of df-consul

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Alex 2022-12-07 14:19:26 +01:00
commit 0a641cae96
Signed by: lx
GPG Key ID: 0E496D15096376BE
3 changed files with 278 additions and 0 deletions

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.gitignore vendored Normal file
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/target
/Cargo.lock

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Cargo.toml Normal file
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[package]
name = "df-consul"
description = "Deuxfleurs' async Rust bindings for (a subset of) the Consul HTTP API"
authors = [ "Alex Auvolat <alex@adnab.me>" ]
version = "0.1.0"
edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
anyhow = "1.0.66"
serde = { version = "1.0.149", features = ["derive"] }
log = "0.4"
bytes = "1"
reqwest = { version = "0.11", default-features = false, features = ["json", "rustls-tls-manual-roots" ] }

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src/lib.rs Normal file
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use std::collections::HashMap;
use std::fs::File;
use std::io::Read;
use anyhow::{anyhow, bail, Result};
use bytes::Bytes;
use log::*;
use reqwest::StatusCode;
use serde::{Deserialize, Serialize};
pub struct ConsulConfig {
pub addr: String,
pub ca_cert: Option<String>,
pub tls_skip_verify: bool,
pub client_cert: Option<String>,
pub client_key: Option<String>,
}
// ---- Watch and retrieve Consul catalog ----
//
#[derive(Serialize, Deserialize, Debug)]
pub struct ConsulNode {
#[serde(rename = "Node")]
pub node: String,
#[serde(rename = "Address")]
pub address: String,
#[serde(rename = "Meta")]
pub meta: HashMap<String, String>,
}
#[derive(Serialize, Deserialize, Debug)]
pub struct ConsulServiceEntry {
#[serde(rename = "Service")]
pub service: String,
#[serde(rename = "Address")]
pub address: String,
#[serde(rename = "Port")]
pub port: u16,
#[serde(rename = "Tags")]
pub tags: Vec<String>,
}
#[derive(Serialize, Deserialize, Debug)]
pub struct ConsulNodeCatalog {
#[serde(rename = "Node")]
pub node: ConsulNode,
#[serde(rename = "Services")]
pub services: HashMap<String, ConsulServiceEntry>,
}
// ---- Consul session management ----
#[derive(Serialize, Deserialize, Debug)]
pub struct ConsulSessionRequest {
#[serde(rename = "Name")]
pub name: String,
#[serde(rename = "Node")]
pub node: Option<String>,
#[serde(rename = "LockDelay")]
pub lock_delay: Option<String>,
#[serde(rename = "TTL")]
pub ttl: Option<String>,
#[serde(rename = "Behavior")]
pub behavior: Option<String>,
}
#[derive(Serialize, Deserialize, Debug)]
pub struct ConsulSessionResponse {
#[serde(rename = "ID")]
pub id: String,
}
#[derive(Clone)]
pub struct Consul {
client: reqwest::Client,
url: String,
kv_prefix: String,
pub local_node: String,
}
impl Consul {
pub fn new(config: ConsulConfig, kv_prefix: &str, local_node: &str) -> Result<Self> {
let client = match (&config.client_cert, &config.client_key) {
(Some(client_cert), Some(client_key)) => {
let mut client_cert_buf = vec![];
File::open(client_cert)?.read_to_end(&mut client_cert_buf)?;
let mut client_key_buf = vec![];
File::open(client_key)?.read_to_end(&mut client_key_buf)?;
let identity = reqwest::Identity::from_pem(
&[&client_cert_buf[..], &client_key_buf[..]].concat()[..],
)?;
if config.tls_skip_verify {
reqwest::Client::builder()
.use_rustls_tls()
.danger_accept_invalid_certs(true)
.identity(identity)
.build()?
} else if let Some(ca_cert) = &config.ca_cert {
let mut ca_cert_buf = vec![];
File::open(ca_cert)?.read_to_end(&mut ca_cert_buf)?;
reqwest::Client::builder()
.use_rustls_tls()
.add_root_certificate(reqwest::Certificate::from_pem(&ca_cert_buf[..])?)
.identity(identity)
.build()?
} else {
reqwest::Client::builder()
.use_rustls_tls()
.identity(identity)
.build()?
}
}
(None, None) => reqwest::Client::new(),
_ => bail!("Incomplete Consul TLS configuration parameters"),
};
Ok(Self {
client,
url: config.addr.trim_end_matches('/').to_string(),
kv_prefix: kv_prefix.to_string(),
local_node: local_node.into(),
})
}
pub async fn list_nodes(&self) -> Result<Vec<ConsulNode>> {
debug!("list_nodes");
let url = format!("{}/v1/catalog/nodes", self.url);
let http = self.client.get(&url).send().await?;
let resp: Vec<ConsulNode> = http.json().await?;
Ok(resp)
}
pub async fn watch_node(
&self,
host: &str,
idx: Option<usize>,
) -> Result<(ConsulNodeCatalog, usize)> {
debug!("watch_node {} {:?}", host, idx);
let url = match idx {
Some(i) => format!("{}/v1/catalog/node/{}?index={}", self.url, host, i),
None => format!("{}/v1/catalog/node/{}", self.url, host),
};
let http = self.client.get(&url).send().await?;
let new_idx = match http.headers().get("X-Consul-Index") {
Some(v) => v.to_str()?.parse::<usize>()?,
None => bail!("X-Consul-Index header not found"),
};
let resp: ConsulNodeCatalog = http.json().await?;
Ok((resp, new_idx))
}
// ---- KV get and put ----
pub async fn kv_get(&self, key: &str) -> Result<Option<Bytes>> {
debug!("kv_get {}", key);
let url = format!("{}/v1/kv/{}{}?raw", self.url, self.kv_prefix, key);
let http = self.client.get(&url).send().await?;
match http.status() {
StatusCode::OK => Ok(Some(http.bytes().await?)),
StatusCode::NOT_FOUND => Ok(None),
_ => Err(anyhow!(
"Consul request failed: {:?}",
http.error_for_status()
)),
}
}
pub async fn kv_get_json<T: for<'de> Deserialize<'de>>(&self, key: &str) -> Result<Option<T>> {
debug!("kv_get_json {}", key);
let url = format!("{}/v1/kv/{}{}?raw", self.url, self.kv_prefix, key);
let http = self.client.get(&url).send().await?;
match http.status() {
StatusCode::OK => Ok(Some(http.json().await?)),
StatusCode::NOT_FOUND => Ok(None),
_ => Err(anyhow!(
"Consul request failed: {:?}",
http.error_for_status()
)),
}
}
pub async fn kv_put(&self, key: &str, bytes: Bytes) -> Result<()> {
debug!("kv_put {}", key);
let url = format!("{}/v1/kv/{}{}", self.url, self.kv_prefix, key);
let http = self.client.put(&url).body(bytes).send().await?;
http.error_for_status()?;
Ok(())
}
pub async fn kv_put_json<T: Serialize>(&self, key: &str, value: &T) -> Result<()> {
debug!("kv_put_json {}", key);
let url = format!("{}/v1/kv/{}{}", self.url, self.kv_prefix, key);
let http = self.client.put(&url).json(value).send().await?;
http.error_for_status()?;
Ok(())
}
pub async fn kv_delete(&self, key: &str) -> Result<()> {
let url = format!("{}/v1/kv/{}{}", self.url, self.kv_prefix, key);
let http = self.client.delete(&url).send().await?;
http.error_for_status()?;
Ok(())
}
// ---- Locking ----
pub async fn create_session(&self, req: &ConsulSessionRequest) -> Result<String> {
debug!("create_session {:?}", req);
let url = format!("{}/v1/session/create", self.url);
let http = self.client.put(&url).json(req).send().await?;
let resp: ConsulSessionResponse = http.json().await?;
Ok(resp.id)
}
pub async fn acquire(&self, key: &str, bytes: Bytes, session: &str) -> Result<bool> {
debug!("acquire {}", key);
let url = format!(
"{}/v1/kv/{}{}?acquire={}",
self.url, self.kv_prefix, key, session
);
let http = self.client.put(&url).body(bytes).send().await?;
let resp: bool = http.json().await?;
Ok(resp)
}
pub async fn release(&self, key: &str, bytes: Bytes, session: &str) -> Result<()> {
debug!("release {}", key);
let url = format!(
"{}/v1/kv/{}{}?release={}",
self.url, self.kv_prefix, key, session
);
let http = self.client.put(&url).body(bytes).send().await?;
http.error_for_status()?;
Ok(())
}
}