billing.rs

  1use anyhow::{anyhow, bail, Context};
  2use axum::{
  3    extract::{self, Query},
  4    routing::{get, post},
  5    Extension, Json, Router,
  6};
  7use chrono::{DateTime, SecondsFormat, Utc};
  8use collections::HashSet;
  9use reqwest::StatusCode;
 10use sea_orm::ActiveValue;
 11use serde::{Deserialize, Serialize};
 12use std::{str::FromStr, sync::Arc, time::Duration};
 13use stripe::{
 14    BillingPortalSession, CreateBillingPortalSession, CreateBillingPortalSessionFlowData,
 15    CreateBillingPortalSessionFlowDataAfterCompletion,
 16    CreateBillingPortalSessionFlowDataAfterCompletionRedirect,
 17    CreateBillingPortalSessionFlowDataType, CreateCustomer, Customer, CustomerId, EventObject,
 18    EventType, Expandable, ListEvents, Subscription, SubscriptionId, SubscriptionStatus,
 19};
 20use util::ResultExt;
 21
 22use crate::llm::{DEFAULT_MAX_MONTHLY_SPEND, FREE_TIER_MONTHLY_SPENDING_LIMIT};
 23use crate::rpc::{ResultExt as _, Server};
 24use crate::{
 25    db::{
 26        billing_customer, BillingSubscriptionId, CreateBillingCustomerParams,
 27        CreateBillingSubscriptionParams, CreateProcessedStripeEventParams,
 28        UpdateBillingCustomerParams, UpdateBillingPreferencesParams,
 29        UpdateBillingSubscriptionParams,
 30    },
 31    stripe_billing::StripeBilling,
 32};
 33use crate::{
 34    db::{billing_subscription::StripeSubscriptionStatus, UserId},
 35    llm::db::LlmDatabase,
 36};
 37use crate::{AppState, Cents, Error, Result};
 38
 39pub fn router() -> Router {
 40    Router::new()
 41        .route(
 42            "/billing/preferences",
 43            get(get_billing_preferences).put(update_billing_preferences),
 44        )
 45        .route(
 46            "/billing/subscriptions",
 47            get(list_billing_subscriptions).post(create_billing_subscription),
 48        )
 49        .route(
 50            "/billing/subscriptions/manage",
 51            post(manage_billing_subscription),
 52        )
 53        .route("/billing/monthly_spend", get(get_monthly_spend))
 54}
 55
 56#[derive(Debug, Deserialize)]
 57struct GetBillingPreferencesParams {
 58    github_user_id: i32,
 59}
 60
 61#[derive(Debug, Serialize)]
 62struct BillingPreferencesResponse {
 63    max_monthly_llm_usage_spending_in_cents: i32,
 64}
 65
 66async fn get_billing_preferences(
 67    Extension(app): Extension<Arc<AppState>>,
 68    Query(params): Query<GetBillingPreferencesParams>,
 69) -> Result<Json<BillingPreferencesResponse>> {
 70    let user = app
 71        .db
 72        .get_user_by_github_user_id(params.github_user_id)
 73        .await?
 74        .ok_or_else(|| anyhow!("user not found"))?;
 75
 76    let preferences = app.db.get_billing_preferences(user.id).await?;
 77
 78    Ok(Json(BillingPreferencesResponse {
 79        max_monthly_llm_usage_spending_in_cents: preferences
 80            .map_or(DEFAULT_MAX_MONTHLY_SPEND.0 as i32, |preferences| {
 81                preferences.max_monthly_llm_usage_spending_in_cents
 82            }),
 83    }))
 84}
 85
 86#[derive(Debug, Deserialize)]
 87struct UpdateBillingPreferencesBody {
 88    github_user_id: i32,
 89    max_monthly_llm_usage_spending_in_cents: i32,
 90}
 91
 92async fn update_billing_preferences(
 93    Extension(app): Extension<Arc<AppState>>,
 94    Extension(rpc_server): Extension<Arc<crate::rpc::Server>>,
 95    extract::Json(body): extract::Json<UpdateBillingPreferencesBody>,
 96) -> Result<Json<BillingPreferencesResponse>> {
 97    let user = app
 98        .db
 99        .get_user_by_github_user_id(body.github_user_id)
100        .await?
101        .ok_or_else(|| anyhow!("user not found"))?;
102
103    let billing_preferences =
104        if let Some(_billing_preferences) = app.db.get_billing_preferences(user.id).await? {
105            app.db
106                .update_billing_preferences(
107                    user.id,
108                    &UpdateBillingPreferencesParams {
109                        max_monthly_llm_usage_spending_in_cents: ActiveValue::set(
110                            body.max_monthly_llm_usage_spending_in_cents,
111                        ),
112                    },
113                )
114                .await?
115        } else {
116            app.db
117                .create_billing_preferences(
118                    user.id,
119                    &crate::db::CreateBillingPreferencesParams {
120                        max_monthly_llm_usage_spending_in_cents: body
121                            .max_monthly_llm_usage_spending_in_cents,
122                    },
123                )
124                .await?
125        };
126
127    rpc_server.refresh_llm_tokens_for_user(user.id).await;
128
129    Ok(Json(BillingPreferencesResponse {
130        max_monthly_llm_usage_spending_in_cents: billing_preferences
131            .max_monthly_llm_usage_spending_in_cents,
132    }))
133}
134
135#[derive(Debug, Deserialize)]
136struct ListBillingSubscriptionsParams {
137    github_user_id: i32,
138}
139
140#[derive(Debug, Serialize)]
141struct BillingSubscriptionJson {
142    id: BillingSubscriptionId,
143    name: String,
144    status: StripeSubscriptionStatus,
145    cancel_at: Option<String>,
146    /// Whether this subscription can be canceled.
147    is_cancelable: bool,
148}
149
150#[derive(Debug, Serialize)]
151struct ListBillingSubscriptionsResponse {
152    subscriptions: Vec<BillingSubscriptionJson>,
153}
154
155async fn list_billing_subscriptions(
156    Extension(app): Extension<Arc<AppState>>,
157    Query(params): Query<ListBillingSubscriptionsParams>,
158) -> Result<Json<ListBillingSubscriptionsResponse>> {
159    let user = app
160        .db
161        .get_user_by_github_user_id(params.github_user_id)
162        .await?
163        .ok_or_else(|| anyhow!("user not found"))?;
164
165    let subscriptions = app.db.get_billing_subscriptions(user.id).await?;
166
167    Ok(Json(ListBillingSubscriptionsResponse {
168        subscriptions: subscriptions
169            .into_iter()
170            .map(|subscription| BillingSubscriptionJson {
171                id: subscription.id,
172                name: "Zed LLM Usage".to_string(),
173                status: subscription.stripe_subscription_status,
174                cancel_at: subscription.stripe_cancel_at.map(|cancel_at| {
175                    cancel_at
176                        .and_utc()
177                        .to_rfc3339_opts(SecondsFormat::Millis, true)
178                }),
179                is_cancelable: subscription.stripe_subscription_status.is_cancelable()
180                    && subscription.stripe_cancel_at.is_none(),
181            })
182            .collect(),
183    }))
184}
185
186#[derive(Debug, Deserialize)]
187struct CreateBillingSubscriptionBody {
188    github_user_id: i32,
189}
190
191#[derive(Debug, Serialize)]
192struct CreateBillingSubscriptionResponse {
193    checkout_session_url: String,
194}
195
196/// Initiates a Stripe Checkout session for creating a billing subscription.
197async fn create_billing_subscription(
198    Extension(app): Extension<Arc<AppState>>,
199    extract::Json(body): extract::Json<CreateBillingSubscriptionBody>,
200) -> Result<Json<CreateBillingSubscriptionResponse>> {
201    let user = app
202        .db
203        .get_user_by_github_user_id(body.github_user_id)
204        .await?
205        .ok_or_else(|| anyhow!("user not found"))?;
206
207    let Some(stripe_client) = app.stripe_client.clone() else {
208        log::error!("failed to retrieve Stripe client");
209        Err(Error::http(
210            StatusCode::NOT_IMPLEMENTED,
211            "not supported".into(),
212        ))?
213    };
214    let Some(stripe_billing) = app.stripe_billing.clone() else {
215        log::error!("failed to retrieve Stripe billing object");
216        Err(Error::http(
217            StatusCode::NOT_IMPLEMENTED,
218            "not supported".into(),
219        ))?
220    };
221    let Some(llm_db) = app.llm_db.clone() else {
222        log::error!("failed to retrieve LLM database");
223        Err(Error::http(
224            StatusCode::NOT_IMPLEMENTED,
225            "not supported".into(),
226        ))?
227    };
228
229    if app.db.has_active_billing_subscription(user.id).await? {
230        return Err(Error::http(
231            StatusCode::CONFLICT,
232            "user already has an active subscription".into(),
233        ));
234    }
235
236    let customer_id =
237        if let Some(existing_customer) = app.db.get_billing_customer_by_user_id(user.id).await? {
238            CustomerId::from_str(&existing_customer.stripe_customer_id)
239                .context("failed to parse customer ID")?
240        } else {
241            let customer = Customer::create(
242                &stripe_client,
243                CreateCustomer {
244                    email: user.email_address.as_deref(),
245                    ..Default::default()
246                },
247            )
248            .await?;
249
250            customer.id
251        };
252
253    let default_model = llm_db.model(rpc::LanguageModelProvider::Anthropic, "claude-3-5-sonnet")?;
254    let stripe_model = stripe_billing.register_model(default_model).await?;
255    let success_url = format!("{}/account", app.config.zed_dot_dev_url());
256    let checkout_session_url = stripe_billing
257        .checkout(customer_id, &user.github_login, &stripe_model, &success_url)
258        .await?;
259    Ok(Json(CreateBillingSubscriptionResponse {
260        checkout_session_url,
261    }))
262}
263
264#[derive(Debug, PartialEq, Deserialize)]
265#[serde(rename_all = "snake_case")]
266enum ManageSubscriptionIntent {
267    /// The user intends to cancel their subscription.
268    Cancel,
269    /// The user intends to stop the cancellation of their subscription.
270    StopCancellation,
271}
272
273#[derive(Debug, Deserialize)]
274struct ManageBillingSubscriptionBody {
275    github_user_id: i32,
276    intent: ManageSubscriptionIntent,
277    /// The ID of the subscription to manage.
278    subscription_id: BillingSubscriptionId,
279}
280
281#[derive(Debug, Serialize)]
282struct ManageBillingSubscriptionResponse {
283    billing_portal_session_url: Option<String>,
284}
285
286/// Initiates a Stripe customer portal session for managing a billing subscription.
287async fn manage_billing_subscription(
288    Extension(app): Extension<Arc<AppState>>,
289    extract::Json(body): extract::Json<ManageBillingSubscriptionBody>,
290) -> Result<Json<ManageBillingSubscriptionResponse>> {
291    let user = app
292        .db
293        .get_user_by_github_user_id(body.github_user_id)
294        .await?
295        .ok_or_else(|| anyhow!("user not found"))?;
296
297    let Some(stripe_client) = app.stripe_client.clone() else {
298        log::error!("failed to retrieve Stripe client");
299        Err(Error::http(
300            StatusCode::NOT_IMPLEMENTED,
301            "not supported".into(),
302        ))?
303    };
304
305    let customer = app
306        .db
307        .get_billing_customer_by_user_id(user.id)
308        .await?
309        .ok_or_else(|| anyhow!("billing customer not found"))?;
310    let customer_id = CustomerId::from_str(&customer.stripe_customer_id)
311        .context("failed to parse customer ID")?;
312
313    let subscription = app
314        .db
315        .get_billing_subscription_by_id(body.subscription_id)
316        .await?
317        .ok_or_else(|| anyhow!("subscription not found"))?;
318
319    if body.intent == ManageSubscriptionIntent::StopCancellation {
320        let subscription_id = SubscriptionId::from_str(&subscription.stripe_subscription_id)
321            .context("failed to parse subscription ID")?;
322
323        let updated_stripe_subscription = Subscription::update(
324            &stripe_client,
325            &subscription_id,
326            stripe::UpdateSubscription {
327                cancel_at_period_end: Some(false),
328                ..Default::default()
329            },
330        )
331        .await?;
332
333        app.db
334            .update_billing_subscription(
335                subscription.id,
336                &UpdateBillingSubscriptionParams {
337                    stripe_cancel_at: ActiveValue::set(
338                        updated_stripe_subscription
339                            .cancel_at
340                            .and_then(|cancel_at| DateTime::from_timestamp(cancel_at, 0))
341                            .map(|time| time.naive_utc()),
342                    ),
343                    ..Default::default()
344                },
345            )
346            .await?;
347
348        return Ok(Json(ManageBillingSubscriptionResponse {
349            billing_portal_session_url: None,
350        }));
351    }
352
353    let flow = match body.intent {
354        ManageSubscriptionIntent::Cancel => CreateBillingPortalSessionFlowData {
355            type_: CreateBillingPortalSessionFlowDataType::SubscriptionCancel,
356            after_completion: Some(CreateBillingPortalSessionFlowDataAfterCompletion {
357                type_: stripe::CreateBillingPortalSessionFlowDataAfterCompletionType::Redirect,
358                redirect: Some(CreateBillingPortalSessionFlowDataAfterCompletionRedirect {
359                    return_url: format!("{}/account", app.config.zed_dot_dev_url()),
360                }),
361                ..Default::default()
362            }),
363            subscription_cancel: Some(
364                stripe::CreateBillingPortalSessionFlowDataSubscriptionCancel {
365                    subscription: subscription.stripe_subscription_id,
366                    retention: None,
367                },
368            ),
369            ..Default::default()
370        },
371        ManageSubscriptionIntent::StopCancellation => unreachable!(),
372    };
373
374    let mut params = CreateBillingPortalSession::new(customer_id);
375    params.flow_data = Some(flow);
376    let return_url = format!("{}/account", app.config.zed_dot_dev_url());
377    params.return_url = Some(&return_url);
378
379    let session = BillingPortalSession::create(&stripe_client, params).await?;
380
381    Ok(Json(ManageBillingSubscriptionResponse {
382        billing_portal_session_url: Some(session.url),
383    }))
384}
385
386/// The amount of time we wait in between each poll of Stripe events.
387///
388/// This value should strike a balance between:
389///   1. Being short enough that we update quickly when something in Stripe changes
390///   2. Being long enough that we don't eat into our rate limits.
391///
392/// As a point of reference, the Sequin folks say they have this at **500ms**:
393///
394/// > We poll the Stripe /events endpoint every 500ms per account
395/// >
396/// > — https://blog.sequinstream.com/events-not-webhooks/
397const POLL_EVENTS_INTERVAL: Duration = Duration::from_secs(5);
398
399/// The maximum number of events to return per page.
400///
401/// We set this to 100 (the max) so we have to make fewer requests to Stripe.
402///
403/// > Limit can range between 1 and 100, and the default is 10.
404const EVENTS_LIMIT_PER_PAGE: u64 = 100;
405
406/// The number of pages consisting entirely of already-processed events that we
407/// will see before we stop retrieving events.
408///
409/// This is used to prevent over-fetching the Stripe events API for events we've
410/// already seen and processed.
411const NUMBER_OF_ALREADY_PROCESSED_PAGES_BEFORE_WE_STOP: usize = 4;
412
413/// Polls the Stripe events API periodically to reconcile the records in our
414/// database with the data in Stripe.
415pub fn poll_stripe_events_periodically(app: Arc<AppState>, rpc_server: Arc<Server>) {
416    let Some(stripe_client) = app.stripe_client.clone() else {
417        log::warn!("failed to retrieve Stripe client");
418        return;
419    };
420
421    let executor = app.executor.clone();
422    executor.spawn_detached({
423        let executor = executor.clone();
424        async move {
425            loop {
426                poll_stripe_events(&app, &rpc_server, &stripe_client)
427                    .await
428                    .log_err();
429
430                executor.sleep(POLL_EVENTS_INTERVAL).await;
431            }
432        }
433    });
434}
435
436async fn poll_stripe_events(
437    app: &Arc<AppState>,
438    rpc_server: &Arc<Server>,
439    stripe_client: &stripe::Client,
440) -> anyhow::Result<()> {
441    fn event_type_to_string(event_type: EventType) -> String {
442        // Calling `to_string` on `stripe::EventType` members gives us a quoted string,
443        // so we need to unquote it.
444        event_type.to_string().trim_matches('"').to_string()
445    }
446
447    let event_types = [
448        EventType::CustomerCreated,
449        EventType::CustomerUpdated,
450        EventType::CustomerSubscriptionCreated,
451        EventType::CustomerSubscriptionUpdated,
452        EventType::CustomerSubscriptionPaused,
453        EventType::CustomerSubscriptionResumed,
454        EventType::CustomerSubscriptionDeleted,
455    ]
456    .into_iter()
457    .map(event_type_to_string)
458    .collect::<Vec<_>>();
459
460    let mut pages_of_already_processed_events = 0;
461    let mut unprocessed_events = Vec::new();
462
463    log::info!(
464        "Stripe events: starting retrieval for {}",
465        event_types.join(", ")
466    );
467    let mut params = ListEvents::new();
468    params.types = Some(event_types.clone());
469    params.limit = Some(EVENTS_LIMIT_PER_PAGE);
470
471    let mut event_pages = stripe::Event::list(&stripe_client, &params)
472        .await?
473        .paginate(params);
474
475    loop {
476        let processed_event_ids = {
477            let event_ids = event_pages
478                .page
479                .data
480                .iter()
481                .map(|event| event.id.as_str())
482                .collect::<Vec<_>>();
483            app.db
484                .get_processed_stripe_events_by_event_ids(&event_ids)
485                .await?
486                .into_iter()
487                .map(|event| event.stripe_event_id)
488                .collect::<Vec<_>>()
489        };
490
491        let mut processed_events_in_page = 0;
492        let events_in_page = event_pages.page.data.len();
493        for event in &event_pages.page.data {
494            if processed_event_ids.contains(&event.id.to_string()) {
495                processed_events_in_page += 1;
496                log::debug!("Stripe events: already processed '{}', skipping", event.id);
497            } else {
498                unprocessed_events.push(event.clone());
499            }
500        }
501
502        if processed_events_in_page == events_in_page {
503            pages_of_already_processed_events += 1;
504        }
505
506        if event_pages.page.has_more {
507            if pages_of_already_processed_events >= NUMBER_OF_ALREADY_PROCESSED_PAGES_BEFORE_WE_STOP
508            {
509                log::info!("Stripe events: stopping, saw {pages_of_already_processed_events} pages of already-processed events");
510                break;
511            } else {
512                log::info!("Stripe events: retrieving next page");
513                event_pages = event_pages.next(&stripe_client).await?;
514            }
515        } else {
516            break;
517        }
518    }
519
520    log::info!("Stripe events: unprocessed {}", unprocessed_events.len());
521
522    // Sort all of the unprocessed events in ascending order, so we can handle them in the order they occurred.
523    unprocessed_events.sort_by(|a, b| a.created.cmp(&b.created).then_with(|| a.id.cmp(&b.id)));
524
525    for event in unprocessed_events {
526        let event_id = event.id.clone();
527        let processed_event_params = CreateProcessedStripeEventParams {
528            stripe_event_id: event.id.to_string(),
529            stripe_event_type: event_type_to_string(event.type_),
530            stripe_event_created_timestamp: event.created,
531        };
532
533        // If the event has happened too far in the past, we don't want to
534        // process it and risk overwriting other more-recent updates.
535        //
536        // 1 day was chosen arbitrarily. This could be made longer or shorter.
537        let one_day = Duration::from_secs(24 * 60 * 60);
538        let a_day_ago = Utc::now() - one_day;
539        if a_day_ago.timestamp() > event.created {
540            log::info!(
541                "Stripe events: event '{}' is more than {one_day:?} old, marking as processed",
542                event_id
543            );
544            app.db
545                .create_processed_stripe_event(&processed_event_params)
546                .await?;
547
548            return Ok(());
549        }
550
551        let process_result = match event.type_ {
552            EventType::CustomerCreated | EventType::CustomerUpdated => {
553                handle_customer_event(app, stripe_client, event).await
554            }
555            EventType::CustomerSubscriptionCreated
556            | EventType::CustomerSubscriptionUpdated
557            | EventType::CustomerSubscriptionPaused
558            | EventType::CustomerSubscriptionResumed
559            | EventType::CustomerSubscriptionDeleted => {
560                handle_customer_subscription_event(app, rpc_server, stripe_client, event).await
561            }
562            _ => Ok(()),
563        };
564
565        if let Some(()) = process_result
566            .with_context(|| format!("failed to process event {event_id} successfully"))
567            .log_err()
568        {
569            app.db
570                .create_processed_stripe_event(&processed_event_params)
571                .await?;
572        }
573    }
574
575    Ok(())
576}
577
578async fn handle_customer_event(
579    app: &Arc<AppState>,
580    _stripe_client: &stripe::Client,
581    event: stripe::Event,
582) -> anyhow::Result<()> {
583    let EventObject::Customer(customer) = event.data.object else {
584        bail!("unexpected event payload for {}", event.id);
585    };
586
587    log::info!("handling Stripe {} event: {}", event.type_, event.id);
588
589    let Some(email) = customer.email else {
590        log::info!("Stripe customer has no email: skipping");
591        return Ok(());
592    };
593
594    let Some(user) = app.db.get_user_by_email(&email).await? else {
595        log::info!("no user found for email: skipping");
596        return Ok(());
597    };
598
599    if let Some(existing_customer) = app
600        .db
601        .get_billing_customer_by_stripe_customer_id(&customer.id)
602        .await?
603    {
604        app.db
605            .update_billing_customer(
606                existing_customer.id,
607                &UpdateBillingCustomerParams {
608                    // For now we just leave the information as-is, as it is not
609                    // likely to change.
610                    ..Default::default()
611                },
612            )
613            .await?;
614    } else {
615        app.db
616            .create_billing_customer(&CreateBillingCustomerParams {
617                user_id: user.id,
618                stripe_customer_id: customer.id.to_string(),
619            })
620            .await?;
621    }
622
623    Ok(())
624}
625
626async fn handle_customer_subscription_event(
627    app: &Arc<AppState>,
628    rpc_server: &Arc<Server>,
629    stripe_client: &stripe::Client,
630    event: stripe::Event,
631) -> anyhow::Result<()> {
632    let EventObject::Subscription(subscription) = event.data.object else {
633        bail!("unexpected event payload for {}", event.id);
634    };
635
636    log::info!("handling Stripe {} event: {}", event.type_, event.id);
637
638    let billing_customer =
639        find_or_create_billing_customer(app, stripe_client, subscription.customer)
640            .await?
641            .ok_or_else(|| anyhow!("billing customer not found"))?;
642
643    if let Some(existing_subscription) = app
644        .db
645        .get_billing_subscription_by_stripe_subscription_id(&subscription.id)
646        .await?
647    {
648        app.db
649            .update_billing_subscription(
650                existing_subscription.id,
651                &UpdateBillingSubscriptionParams {
652                    billing_customer_id: ActiveValue::set(billing_customer.id),
653                    stripe_subscription_id: ActiveValue::set(subscription.id.to_string()),
654                    stripe_subscription_status: ActiveValue::set(subscription.status.into()),
655                    stripe_cancel_at: ActiveValue::set(
656                        subscription
657                            .cancel_at
658                            .and_then(|cancel_at| DateTime::from_timestamp(cancel_at, 0))
659                            .map(|time| time.naive_utc()),
660                    ),
661                },
662            )
663            .await?;
664    } else {
665        // If the user already has an active billing subscription, ignore the
666        // event and return an `Ok` to signal that it was processed
667        // successfully.
668        //
669        // There is the possibility that this could cause us to not create a
670        // subscription in the following scenario:
671        //
672        //   1. User has an active subscription A
673        //   2. User cancels subscription A
674        //   3. User creates a new subscription B
675        //   4. We process the new subscription B before the cancellation of subscription A
676        //   5. User ends up with no subscriptions
677        //
678        // In theory this situation shouldn't arise as we try to process the events in the order they occur.
679        if app
680            .db
681            .has_active_billing_subscription(billing_customer.user_id)
682            .await?
683        {
684            log::info!(
685                "user {user_id} already has an active subscription, skipping creation of subscription {subscription_id}",
686                user_id = billing_customer.user_id,
687                subscription_id = subscription.id
688            );
689            return Ok(());
690        }
691
692        app.db
693            .create_billing_subscription(&CreateBillingSubscriptionParams {
694                billing_customer_id: billing_customer.id,
695                stripe_subscription_id: subscription.id.to_string(),
696                stripe_subscription_status: subscription.status.into(),
697            })
698            .await?;
699    }
700
701    // When the user's subscription changes, we want to refresh their LLM tokens
702    // to either grant/revoke access.
703    rpc_server
704        .refresh_llm_tokens_for_user(billing_customer.user_id)
705        .await;
706
707    Ok(())
708}
709
710#[derive(Debug, Deserialize)]
711struct GetMonthlySpendParams {
712    github_user_id: i32,
713}
714
715#[derive(Debug, Serialize)]
716struct GetMonthlySpendResponse {
717    monthly_free_tier_spend_in_cents: u32,
718    monthly_free_tier_allowance_in_cents: u32,
719    monthly_spend_in_cents: u32,
720}
721
722async fn get_monthly_spend(
723    Extension(app): Extension<Arc<AppState>>,
724    Query(params): Query<GetMonthlySpendParams>,
725) -> Result<Json<GetMonthlySpendResponse>> {
726    let user = app
727        .db
728        .get_user_by_github_user_id(params.github_user_id)
729        .await?
730        .ok_or_else(|| anyhow!("user not found"))?;
731
732    let Some(llm_db) = app.llm_db.clone() else {
733        return Err(Error::http(
734            StatusCode::NOT_IMPLEMENTED,
735            "LLM database not available".into(),
736        ));
737    };
738
739    let free_tier = user
740        .custom_llm_monthly_allowance_in_cents
741        .map(|allowance| Cents(allowance as u32))
742        .unwrap_or(FREE_TIER_MONTHLY_SPENDING_LIMIT);
743
744    let spending_for_month = llm_db
745        .get_user_spending_for_month(user.id, Utc::now())
746        .await?;
747
748    let free_tier_spend = Cents::min(spending_for_month, free_tier);
749    let monthly_spend = spending_for_month.saturating_sub(free_tier);
750
751    Ok(Json(GetMonthlySpendResponse {
752        monthly_free_tier_spend_in_cents: free_tier_spend.0,
753        monthly_free_tier_allowance_in_cents: free_tier.0,
754        monthly_spend_in_cents: monthly_spend.0,
755    }))
756}
757
758impl From<SubscriptionStatus> for StripeSubscriptionStatus {
759    fn from(value: SubscriptionStatus) -> Self {
760        match value {
761            SubscriptionStatus::Incomplete => Self::Incomplete,
762            SubscriptionStatus::IncompleteExpired => Self::IncompleteExpired,
763            SubscriptionStatus::Trialing => Self::Trialing,
764            SubscriptionStatus::Active => Self::Active,
765            SubscriptionStatus::PastDue => Self::PastDue,
766            SubscriptionStatus::Canceled => Self::Canceled,
767            SubscriptionStatus::Unpaid => Self::Unpaid,
768            SubscriptionStatus::Paused => Self::Paused,
769        }
770    }
771}
772
773/// Finds or creates a billing customer using the provided customer.
774async fn find_or_create_billing_customer(
775    app: &Arc<AppState>,
776    stripe_client: &stripe::Client,
777    customer_or_id: Expandable<Customer>,
778) -> anyhow::Result<Option<billing_customer::Model>> {
779    let customer_id = match &customer_or_id {
780        Expandable::Id(id) => id,
781        Expandable::Object(customer) => customer.id.as_ref(),
782    };
783
784    // If we already have a billing customer record associated with the Stripe customer,
785    // there's nothing more we need to do.
786    if let Some(billing_customer) = app
787        .db
788        .get_billing_customer_by_stripe_customer_id(customer_id)
789        .await?
790    {
791        return Ok(Some(billing_customer));
792    }
793
794    // If all we have is a customer ID, resolve it to a full customer record by
795    // hitting the Stripe API.
796    let customer = match customer_or_id {
797        Expandable::Id(id) => Customer::retrieve(stripe_client, &id, &[]).await?,
798        Expandable::Object(customer) => *customer,
799    };
800
801    let Some(email) = customer.email else {
802        return Ok(None);
803    };
804
805    let Some(user) = app.db.get_user_by_email(&email).await? else {
806        return Ok(None);
807    };
808
809    let billing_customer = app
810        .db
811        .create_billing_customer(&CreateBillingCustomerParams {
812            user_id: user.id,
813            stripe_customer_id: customer.id.to_string(),
814        })
815        .await?;
816
817    Ok(Some(billing_customer))
818}
819
820const SYNC_LLM_USAGE_WITH_STRIPE_INTERVAL: Duration = Duration::from_secs(60);
821
822pub fn sync_llm_usage_with_stripe_periodically(app: Arc<AppState>) {
823    let Some(stripe_billing) = app.stripe_billing.clone() else {
824        log::warn!("failed to retrieve Stripe billing object");
825        return;
826    };
827    let Some(llm_db) = app.llm_db.clone() else {
828        log::warn!("failed to retrieve LLM database");
829        return;
830    };
831
832    let executor = app.executor.clone();
833    executor.spawn_detached({
834        let executor = executor.clone();
835        async move {
836            loop {
837                sync_with_stripe(&app, &llm_db, &stripe_billing)
838                    .await
839                    .context("failed to sync LLM usage to Stripe")
840                    .trace_err();
841                executor.sleep(SYNC_LLM_USAGE_WITH_STRIPE_INTERVAL).await;
842            }
843        }
844    });
845}
846
847async fn sync_with_stripe(
848    app: &Arc<AppState>,
849    llm_db: &Arc<LlmDatabase>,
850    stripe_billing: &Arc<StripeBilling>,
851) -> anyhow::Result<()> {
852    let events = llm_db.get_billing_events().await?;
853    let user_ids = events
854        .iter()
855        .map(|(event, _)| event.user_id)
856        .collect::<HashSet<UserId>>();
857    let stripe_subscriptions = app.db.get_active_billing_subscriptions(user_ids).await?;
858
859    for (event, model) in events {
860        let Some((stripe_db_customer, stripe_db_subscription)) =
861            stripe_subscriptions.get(&event.user_id)
862        else {
863            tracing::warn!(
864                user_id = event.user_id.0,
865                "Registered billing event for user who is not a Stripe customer. Billing events should only be created for users who are Stripe customers, so this is a mistake on our side."
866            );
867            continue;
868        };
869        let stripe_subscription_id: stripe::SubscriptionId = stripe_db_subscription
870            .stripe_subscription_id
871            .parse()
872            .context("failed to parse stripe subscription id from db")?;
873        let stripe_customer_id: stripe::CustomerId = stripe_db_customer
874            .stripe_customer_id
875            .parse()
876            .context("failed to parse stripe customer id from db")?;
877
878        let stripe_model = stripe_billing.register_model(&model).await?;
879        stripe_billing
880            .subscribe_to_model(&stripe_subscription_id, &stripe_model)
881            .await?;
882        stripe_billing
883            .bill_model_usage(&stripe_customer_id, &stripe_model, &event)
884            .await?;
885        llm_db.consume_billing_event(event.id).await?;
886    }
887
888    Ok(())
889}