greentic_runner_host/
runtime.rs

1use std::collections::HashMap;
2use std::num::NonZeroUsize;
3use std::path::Path;
4use std::sync::Arc;
5use std::time::Instant;
6
7use anyhow::{Context, Result, bail};
8use arc_swap::ArcSwap;
9use axum::http::StatusCode;
10use lru::LruCache;
11use parking_lot::Mutex;
12use reqwest::Client;
13use serde_json::Value;
14use tokio::task::JoinHandle;
15
16use crate::config::HostConfig;
17use crate::engine::host::{SessionHost, StateHost};
18use crate::engine::runtime::StateMachineRuntime;
19use crate::pack::PackRuntime;
20use crate::runner::engine::FlowEngine;
21use crate::runner::mocks::MockLayer;
22use crate::secrets::{DynSecretsManager, read_secret_blocking};
23use crate::storage::session::DynSessionStore;
24use crate::storage::state::DynStateStore;
25use crate::wasi::RunnerWasiPolicy;
26
27const TELEGRAM_CACHE_CAPACITY: usize = 1024;
28const WEBHOOK_CACHE_CAPACITY: usize = 256;
29
30/// Atomically swapped view of live tenant runtimes.
31pub struct ActivePacks {
32    inner: ArcSwap<HashMap<String, Arc<TenantRuntime>>>,
33}
34
35impl ActivePacks {
36    pub fn new() -> Self {
37        Self {
38            inner: ArcSwap::from_pointee(HashMap::new()),
39        }
40    }
41
42    pub fn load(&self, tenant: &str) -> Option<Arc<TenantRuntime>> {
43        self.inner.load().get(tenant).cloned()
44    }
45
46    pub fn snapshot(&self) -> Arc<HashMap<String, Arc<TenantRuntime>>> {
47        self.inner.load_full()
48    }
49
50    pub fn replace(&self, next: HashMap<String, Arc<TenantRuntime>>) {
51        self.inner.store(Arc::new(next));
52    }
53
54    pub fn len(&self) -> usize {
55        self.inner.load().len()
56    }
57
58    pub fn is_empty(&self) -> bool {
59        self.len() == 0
60    }
61}
62
63impl Default for ActivePacks {
64    fn default() -> Self {
65        Self::new()
66    }
67}
68
69/// Runtime bundle for a tenant pack.
70pub struct TenantRuntime {
71    tenant: String,
72    config: Arc<HostConfig>,
73    packs: Vec<Arc<PackRuntime>>,
74    digests: Vec<Option<String>>,
75    engine: Arc<FlowEngine>,
76    state_machine: Arc<StateMachineRuntime>,
77    http_client: Client,
78    telegram_cache: Mutex<LruCache<i64, StatusCode>>,
79    webhook_cache: Mutex<LruCache<String, Value>>,
80    messaging_rate: Mutex<RateLimiter>,
81    mocks: Option<Arc<MockLayer>>,
82    timer_handles: Mutex<Vec<JoinHandle<()>>>,
83    secrets: DynSecretsManager,
84}
85
86impl TenantRuntime {
87    #[allow(clippy::too_many_arguments)]
88    pub async fn load(
89        pack_path: &Path,
90        config: Arc<HostConfig>,
91        mocks: Option<Arc<MockLayer>>,
92        archive_source: Option<&Path>,
93        digest: Option<String>,
94        wasi_policy: Arc<RunnerWasiPolicy>,
95        session_host: Arc<dyn SessionHost>,
96        session_store: DynSessionStore,
97        state_store: DynStateStore,
98        state_host: Arc<dyn StateHost>,
99        secrets_manager: DynSecretsManager,
100    ) -> Result<Arc<Self>> {
101        let pack = Arc::new(
102            PackRuntime::load(
103                pack_path,
104                Arc::clone(&config),
105                mocks.clone(),
106                archive_source,
107                Some(Arc::clone(&session_store)),
108                Some(Arc::clone(&state_store)),
109                Arc::clone(&wasi_policy),
110                Arc::clone(&secrets_manager),
111                true,
112            )
113            .await
114            .with_context(|| {
115                format!(
116                    "failed to load pack {} for tenant {}",
117                    pack_path.display(),
118                    config.tenant
119                )
120            })?,
121        );
122        Self::from_packs(
123            config,
124            vec![(pack, digest)],
125            mocks,
126            session_host,
127            session_store,
128            state_store,
129            state_host,
130            secrets_manager,
131        )
132        .await
133    }
134
135    #[allow(clippy::too_many_arguments)]
136    pub async fn from_packs(
137        config: Arc<HostConfig>,
138        packs: Vec<(Arc<PackRuntime>, Option<String>)>,
139        mocks: Option<Arc<MockLayer>>,
140        session_host: Arc<dyn SessionHost>,
141        session_store: DynSessionStore,
142        _state_store: DynStateStore,
143        state_host: Arc<dyn StateHost>,
144        secrets_manager: DynSecretsManager,
145    ) -> Result<Arc<Self>> {
146        let telegram_capacity = NonZeroUsize::new(TELEGRAM_CACHE_CAPACITY)
147            .expect("telegram cache capacity must be > 0");
148        let webhook_capacity =
149            NonZeroUsize::new(WEBHOOK_CACHE_CAPACITY).expect("webhook cache capacity must be > 0");
150        let pack_runtimes = packs
151            .iter()
152            .map(|(pack, _)| Arc::clone(pack))
153            .collect::<Vec<_>>();
154        let digests = packs
155            .iter()
156            .map(|(_, digest)| digest.clone())
157            .collect::<Vec<_>>();
158        let engine = Arc::new(
159            FlowEngine::new(pack_runtimes.clone(), Arc::clone(&config))
160                .await
161                .context("failed to prime flow engine")?,
162        );
163        let state_machine = Arc::new(
164            StateMachineRuntime::from_flow_engine(
165                Arc::clone(&config),
166                Arc::clone(&engine),
167                session_host,
168                session_store,
169                state_host,
170                Arc::clone(&secrets_manager),
171                mocks.clone(),
172            )
173            .context("failed to initialise state machine runtime")?,
174        );
175        let http_client = Client::builder().build()?;
176        let rate_limits = config.rate_limits.clone();
177        Ok(Arc::new(Self {
178            tenant: config.tenant.clone(),
179            config,
180            packs: pack_runtimes,
181            digests,
182            engine,
183            state_machine,
184            http_client,
185            telegram_cache: Mutex::new(LruCache::new(telegram_capacity)),
186            webhook_cache: Mutex::new(LruCache::new(webhook_capacity)),
187            messaging_rate: Mutex::new(RateLimiter::new(
188                rate_limits.messaging_send_qps,
189                rate_limits.messaging_burst,
190            )),
191            mocks,
192            timer_handles: Mutex::new(Vec::new()),
193            secrets: secrets_manager,
194        }))
195    }
196
197    pub fn tenant(&self) -> &str {
198        &self.tenant
199    }
200
201    pub fn config(&self) -> &Arc<HostConfig> {
202        &self.config
203    }
204
205    pub fn main_pack(&self) -> &Arc<PackRuntime> {
206        self.packs
207            .first()
208            .expect("tenant runtime must contain at least one pack")
209    }
210
211    pub fn pack(&self) -> Arc<PackRuntime> {
212        Arc::clone(self.main_pack())
213    }
214
215    pub fn overlays(&self) -> Vec<Arc<PackRuntime>> {
216        self.packs.iter().skip(1).cloned().collect()
217    }
218
219    pub fn engine(&self) -> &Arc<FlowEngine> {
220        &self.engine
221    }
222
223    pub fn state_machine(&self) -> &Arc<StateMachineRuntime> {
224        &self.state_machine
225    }
226
227    pub fn http_client(&self) -> &Client {
228        &self.http_client
229    }
230
231    pub fn digest(&self) -> Option<&str> {
232        self.digests.first().and_then(|d| d.as_deref())
233    }
234
235    pub fn overlay_digests(&self) -> Vec<Option<String>> {
236        self.digests.iter().skip(1).cloned().collect()
237    }
238
239    pub fn telegram_cache(&self) -> &Mutex<LruCache<i64, StatusCode>> {
240        &self.telegram_cache
241    }
242
243    pub fn webhook_cache(&self) -> &Mutex<LruCache<String, Value>> {
244        &self.webhook_cache
245    }
246
247    pub fn messaging_rate(&self) -> &Mutex<RateLimiter> {
248        &self.messaging_rate
249    }
250
251    pub fn mocks(&self) -> Option<&Arc<MockLayer>> {
252        self.mocks.as_ref()
253    }
254
255    pub fn register_timers(&self, handles: Vec<JoinHandle<()>>) {
256        self.timer_handles.lock().extend(handles);
257    }
258
259    pub fn get_secret(&self, key: &str) -> Result<String> {
260        if !self.config.secrets_policy.is_allowed(key) {
261            bail!("secret {key} is not permitted by bindings policy");
262        }
263        let bytes = read_secret_blocking(&self.secrets, key)
264            .context("failed to read secret from manager")?;
265        let value = String::from_utf8(bytes).context("secret value is not valid UTF-8")?;
266        Ok(value)
267    }
268}
269
270impl Drop for TenantRuntime {
271    fn drop(&mut self) {
272        for handle in self.timer_handles.lock().drain(..) {
273            handle.abort();
274        }
275    }
276}
277
278pub struct RateLimiter {
279    allowance: f64,
280    rate: f64,
281    burst: f64,
282    last_check: Instant,
283}
284
285impl RateLimiter {
286    pub fn new(qps: u32, burst: u32) -> Self {
287        let rate = qps.max(1) as f64;
288        let burst = burst.max(1) as f64;
289        Self {
290            allowance: burst,
291            rate,
292            burst,
293            last_check: Instant::now(),
294        }
295    }
296
297    pub fn try_acquire(&mut self) -> bool {
298        let now = Instant::now();
299        let elapsed = now.duration_since(self.last_check).as_secs_f64();
300        self.last_check = now;
301        self.allowance += elapsed * self.rate;
302        if self.allowance > self.burst {
303            self.allowance = self.burst;
304        }
305        if self.allowance < 1.0 {
306            false
307        } else {
308            self.allowance -= 1.0;
309            true
310        }
311    }
312}