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 serde_json::json;
 13use std::{str::FromStr, sync::Arc, time::Duration};
 14use stripe::{
 15    BillingPortalSession, CancellationDetailsReason, CreateBillingPortalSession,
 16    CreateBillingPortalSessionFlowData, CreateBillingPortalSessionFlowDataAfterCompletion,
 17    CreateBillingPortalSessionFlowDataAfterCompletionRedirect,
 18    CreateBillingPortalSessionFlowDataType, CreateCustomer, Customer, CustomerId, EventObject,
 19    EventType, Expandable, ListEvents, Subscription, SubscriptionId, SubscriptionStatus,
 20};
 21use util::ResultExt;
 22
 23use crate::api::events::SnowflakeRow;
 24use crate::db::billing_subscription::{StripeCancellationReason, StripeSubscriptionStatus};
 25use crate::llm::{DEFAULT_MAX_MONTHLY_SPEND, FREE_TIER_MONTHLY_SPENDING_LIMIT};
 26use crate::rpc::{ResultExt as _, Server};
 27use crate::{db::UserId, llm::db::LlmDatabase};
 28use crate::{
 29    db::{
 30        billing_customer, BillingSubscriptionId, CreateBillingCustomerParams,
 31        CreateBillingSubscriptionParams, CreateProcessedStripeEventParams,
 32        UpdateBillingCustomerParams, UpdateBillingPreferencesParams,
 33        UpdateBillingSubscriptionParams,
 34    },
 35    stripe_billing::StripeBilling,
 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 max_monthly_llm_usage_spending_in_cents =
104        body.max_monthly_llm_usage_spending_in_cents.max(0);
105
106    let billing_preferences =
107        if let Some(_billing_preferences) = app.db.get_billing_preferences(user.id).await? {
108            app.db
109                .update_billing_preferences(
110                    user.id,
111                    &UpdateBillingPreferencesParams {
112                        max_monthly_llm_usage_spending_in_cents: ActiveValue::set(
113                            max_monthly_llm_usage_spending_in_cents,
114                        ),
115                    },
116                )
117                .await?
118        } else {
119            app.db
120                .create_billing_preferences(
121                    user.id,
122                    &crate::db::CreateBillingPreferencesParams {
123                        max_monthly_llm_usage_spending_in_cents,
124                    },
125                )
126                .await?
127        };
128
129    SnowflakeRow::new(
130        "Spend Limit Updated",
131        user.metrics_id,
132        user.admin,
133        None,
134        json!({
135            "user_id": user.id,
136            "max_monthly_llm_usage_spending_in_cents": billing_preferences.max_monthly_llm_usage_spending_in_cents,
137        }),
138    )
139    .write(&app.kinesis_client, &app.config.kinesis_stream)
140    .await
141    .log_err();
142
143    rpc_server.refresh_llm_tokens_for_user(user.id).await;
144
145    Ok(Json(BillingPreferencesResponse {
146        max_monthly_llm_usage_spending_in_cents: billing_preferences
147            .max_monthly_llm_usage_spending_in_cents,
148    }))
149}
150
151#[derive(Debug, Deserialize)]
152struct ListBillingSubscriptionsParams {
153    github_user_id: i32,
154}
155
156#[derive(Debug, Serialize)]
157struct BillingSubscriptionJson {
158    id: BillingSubscriptionId,
159    name: String,
160    status: StripeSubscriptionStatus,
161    cancel_at: Option<String>,
162    /// Whether this subscription can be canceled.
163    is_cancelable: bool,
164}
165
166#[derive(Debug, Serialize)]
167struct ListBillingSubscriptionsResponse {
168    subscriptions: Vec<BillingSubscriptionJson>,
169}
170
171async fn list_billing_subscriptions(
172    Extension(app): Extension<Arc<AppState>>,
173    Query(params): Query<ListBillingSubscriptionsParams>,
174) -> Result<Json<ListBillingSubscriptionsResponse>> {
175    let user = app
176        .db
177        .get_user_by_github_user_id(params.github_user_id)
178        .await?
179        .ok_or_else(|| anyhow!("user not found"))?;
180
181    let subscriptions = app.db.get_billing_subscriptions(user.id).await?;
182
183    Ok(Json(ListBillingSubscriptionsResponse {
184        subscriptions: subscriptions
185            .into_iter()
186            .map(|subscription| BillingSubscriptionJson {
187                id: subscription.id,
188                name: "Zed LLM Usage".to_string(),
189                status: subscription.stripe_subscription_status,
190                cancel_at: subscription.stripe_cancel_at.map(|cancel_at| {
191                    cancel_at
192                        .and_utc()
193                        .to_rfc3339_opts(SecondsFormat::Millis, true)
194                }),
195                is_cancelable: subscription.stripe_subscription_status.is_cancelable()
196                    && subscription.stripe_cancel_at.is_none(),
197            })
198            .collect(),
199    }))
200}
201
202#[derive(Debug, Deserialize)]
203struct CreateBillingSubscriptionBody {
204    github_user_id: i32,
205}
206
207#[derive(Debug, Serialize)]
208struct CreateBillingSubscriptionResponse {
209    checkout_session_url: String,
210}
211
212/// Initiates a Stripe Checkout session for creating a billing subscription.
213async fn create_billing_subscription(
214    Extension(app): Extension<Arc<AppState>>,
215    extract::Json(body): extract::Json<CreateBillingSubscriptionBody>,
216) -> Result<Json<CreateBillingSubscriptionResponse>> {
217    let user = app
218        .db
219        .get_user_by_github_user_id(body.github_user_id)
220        .await?
221        .ok_or_else(|| anyhow!("user not found"))?;
222
223    let Some(stripe_client) = app.stripe_client.clone() else {
224        log::error!("failed to retrieve Stripe client");
225        Err(Error::http(
226            StatusCode::NOT_IMPLEMENTED,
227            "not supported".into(),
228        ))?
229    };
230    let Some(stripe_billing) = app.stripe_billing.clone() else {
231        log::error!("failed to retrieve Stripe billing object");
232        Err(Error::http(
233            StatusCode::NOT_IMPLEMENTED,
234            "not supported".into(),
235        ))?
236    };
237    let Some(llm_db) = app.llm_db.clone() else {
238        log::error!("failed to retrieve LLM database");
239        Err(Error::http(
240            StatusCode::NOT_IMPLEMENTED,
241            "not supported".into(),
242        ))?
243    };
244
245    if app.db.has_active_billing_subscription(user.id).await? {
246        return Err(Error::http(
247            StatusCode::CONFLICT,
248            "user already has an active subscription".into(),
249        ));
250    }
251
252    let customer_id =
253        if let Some(existing_customer) = app.db.get_billing_customer_by_user_id(user.id).await? {
254            CustomerId::from_str(&existing_customer.stripe_customer_id)
255                .context("failed to parse customer ID")?
256        } else {
257            let customer = Customer::create(
258                &stripe_client,
259                CreateCustomer {
260                    email: user.email_address.as_deref(),
261                    ..Default::default()
262                },
263            )
264            .await?;
265
266            customer.id
267        };
268
269    let default_model = llm_db.model(rpc::LanguageModelProvider::Anthropic, "claude-3-5-sonnet")?;
270    let stripe_model = stripe_billing.register_model(default_model).await?;
271    let success_url = format!(
272        "{}/account?checkout_complete=1",
273        app.config.zed_dot_dev_url()
274    );
275    let checkout_session_url = stripe_billing
276        .checkout(customer_id, &user.github_login, &stripe_model, &success_url)
277        .await?;
278    Ok(Json(CreateBillingSubscriptionResponse {
279        checkout_session_url,
280    }))
281}
282
283#[derive(Debug, PartialEq, Deserialize)]
284#[serde(rename_all = "snake_case")]
285enum ManageSubscriptionIntent {
286    /// The user intends to cancel their subscription.
287    Cancel,
288    /// The user intends to stop the cancellation of their subscription.
289    StopCancellation,
290}
291
292#[derive(Debug, Deserialize)]
293struct ManageBillingSubscriptionBody {
294    github_user_id: i32,
295    intent: ManageSubscriptionIntent,
296    /// The ID of the subscription to manage.
297    subscription_id: BillingSubscriptionId,
298}
299
300#[derive(Debug, Serialize)]
301struct ManageBillingSubscriptionResponse {
302    billing_portal_session_url: Option<String>,
303}
304
305/// Initiates a Stripe customer portal session for managing a billing subscription.
306async fn manage_billing_subscription(
307    Extension(app): Extension<Arc<AppState>>,
308    extract::Json(body): extract::Json<ManageBillingSubscriptionBody>,
309) -> Result<Json<ManageBillingSubscriptionResponse>> {
310    let user = app
311        .db
312        .get_user_by_github_user_id(body.github_user_id)
313        .await?
314        .ok_or_else(|| anyhow!("user not found"))?;
315
316    let Some(stripe_client) = app.stripe_client.clone() else {
317        log::error!("failed to retrieve Stripe client");
318        Err(Error::http(
319            StatusCode::NOT_IMPLEMENTED,
320            "not supported".into(),
321        ))?
322    };
323
324    let customer = app
325        .db
326        .get_billing_customer_by_user_id(user.id)
327        .await?
328        .ok_or_else(|| anyhow!("billing customer not found"))?;
329    let customer_id = CustomerId::from_str(&customer.stripe_customer_id)
330        .context("failed to parse customer ID")?;
331
332    let subscription = app
333        .db
334        .get_billing_subscription_by_id(body.subscription_id)
335        .await?
336        .ok_or_else(|| anyhow!("subscription not found"))?;
337
338    if body.intent == ManageSubscriptionIntent::StopCancellation {
339        let subscription_id = SubscriptionId::from_str(&subscription.stripe_subscription_id)
340            .context("failed to parse subscription ID")?;
341
342        let updated_stripe_subscription = Subscription::update(
343            &stripe_client,
344            &subscription_id,
345            stripe::UpdateSubscription {
346                cancel_at_period_end: Some(false),
347                ..Default::default()
348            },
349        )
350        .await?;
351
352        app.db
353            .update_billing_subscription(
354                subscription.id,
355                &UpdateBillingSubscriptionParams {
356                    stripe_cancel_at: ActiveValue::set(
357                        updated_stripe_subscription
358                            .cancel_at
359                            .and_then(|cancel_at| DateTime::from_timestamp(cancel_at, 0))
360                            .map(|time| time.naive_utc()),
361                    ),
362                    ..Default::default()
363                },
364            )
365            .await?;
366
367        return Ok(Json(ManageBillingSubscriptionResponse {
368            billing_portal_session_url: None,
369        }));
370    }
371
372    let flow = match body.intent {
373        ManageSubscriptionIntent::Cancel => CreateBillingPortalSessionFlowData {
374            type_: CreateBillingPortalSessionFlowDataType::SubscriptionCancel,
375            after_completion: Some(CreateBillingPortalSessionFlowDataAfterCompletion {
376                type_: stripe::CreateBillingPortalSessionFlowDataAfterCompletionType::Redirect,
377                redirect: Some(CreateBillingPortalSessionFlowDataAfterCompletionRedirect {
378                    return_url: format!("{}/account", app.config.zed_dot_dev_url()),
379                }),
380                ..Default::default()
381            }),
382            subscription_cancel: Some(
383                stripe::CreateBillingPortalSessionFlowDataSubscriptionCancel {
384                    subscription: subscription.stripe_subscription_id,
385                    retention: None,
386                },
387            ),
388            ..Default::default()
389        },
390        ManageSubscriptionIntent::StopCancellation => unreachable!(),
391    };
392
393    let mut params = CreateBillingPortalSession::new(customer_id);
394    params.flow_data = Some(flow);
395    let return_url = format!("{}/account", app.config.zed_dot_dev_url());
396    params.return_url = Some(&return_url);
397
398    let session = BillingPortalSession::create(&stripe_client, params).await?;
399
400    Ok(Json(ManageBillingSubscriptionResponse {
401        billing_portal_session_url: Some(session.url),
402    }))
403}
404
405/// The amount of time we wait in between each poll of Stripe events.
406///
407/// This value should strike a balance between:
408///   1. Being short enough that we update quickly when something in Stripe changes
409///   2. Being long enough that we don't eat into our rate limits.
410///
411/// As a point of reference, the Sequin folks say they have this at **500ms**:
412///
413/// > We poll the Stripe /events endpoint every 500ms per account
414/// >
415/// > — https://blog.sequinstream.com/events-not-webhooks/
416const POLL_EVENTS_INTERVAL: Duration = Duration::from_secs(5);
417
418/// The maximum number of events to return per page.
419///
420/// We set this to 100 (the max) so we have to make fewer requests to Stripe.
421///
422/// > Limit can range between 1 and 100, and the default is 10.
423const EVENTS_LIMIT_PER_PAGE: u64 = 100;
424
425/// The number of pages consisting entirely of already-processed events that we
426/// will see before we stop retrieving events.
427///
428/// This is used to prevent over-fetching the Stripe events API for events we've
429/// already seen and processed.
430const NUMBER_OF_ALREADY_PROCESSED_PAGES_BEFORE_WE_STOP: usize = 4;
431
432/// Polls the Stripe events API periodically to reconcile the records in our
433/// database with the data in Stripe.
434pub fn poll_stripe_events_periodically(app: Arc<AppState>, rpc_server: Arc<Server>) {
435    let Some(stripe_client) = app.stripe_client.clone() else {
436        log::warn!("failed to retrieve Stripe client");
437        return;
438    };
439
440    let executor = app.executor.clone();
441    executor.spawn_detached({
442        let executor = executor.clone();
443        async move {
444            loop {
445                poll_stripe_events(&app, &rpc_server, &stripe_client)
446                    .await
447                    .log_err();
448
449                executor.sleep(POLL_EVENTS_INTERVAL).await;
450            }
451        }
452    });
453}
454
455async fn poll_stripe_events(
456    app: &Arc<AppState>,
457    rpc_server: &Arc<Server>,
458    stripe_client: &stripe::Client,
459) -> anyhow::Result<()> {
460    fn event_type_to_string(event_type: EventType) -> String {
461        // Calling `to_string` on `stripe::EventType` members gives us a quoted string,
462        // so we need to unquote it.
463        event_type.to_string().trim_matches('"').to_string()
464    }
465
466    let event_types = [
467        EventType::CustomerCreated,
468        EventType::CustomerUpdated,
469        EventType::CustomerSubscriptionCreated,
470        EventType::CustomerSubscriptionUpdated,
471        EventType::CustomerSubscriptionPaused,
472        EventType::CustomerSubscriptionResumed,
473        EventType::CustomerSubscriptionDeleted,
474    ]
475    .into_iter()
476    .map(event_type_to_string)
477    .collect::<Vec<_>>();
478
479    let mut pages_of_already_processed_events = 0;
480    let mut unprocessed_events = Vec::new();
481
482    log::info!(
483        "Stripe events: starting retrieval for {}",
484        event_types.join(", ")
485    );
486    let mut params = ListEvents::new();
487    params.types = Some(event_types.clone());
488    params.limit = Some(EVENTS_LIMIT_PER_PAGE);
489
490    let mut event_pages = stripe::Event::list(&stripe_client, &params)
491        .await?
492        .paginate(params);
493
494    loop {
495        let processed_event_ids = {
496            let event_ids = event_pages
497                .page
498                .data
499                .iter()
500                .map(|event| event.id.as_str())
501                .collect::<Vec<_>>();
502            app.db
503                .get_processed_stripe_events_by_event_ids(&event_ids)
504                .await?
505                .into_iter()
506                .map(|event| event.stripe_event_id)
507                .collect::<Vec<_>>()
508        };
509
510        let mut processed_events_in_page = 0;
511        let events_in_page = event_pages.page.data.len();
512        for event in &event_pages.page.data {
513            if processed_event_ids.contains(&event.id.to_string()) {
514                processed_events_in_page += 1;
515                log::debug!("Stripe events: already processed '{}', skipping", event.id);
516            } else {
517                unprocessed_events.push(event.clone());
518            }
519        }
520
521        if processed_events_in_page == events_in_page {
522            pages_of_already_processed_events += 1;
523        }
524
525        if event_pages.page.has_more {
526            if pages_of_already_processed_events >= NUMBER_OF_ALREADY_PROCESSED_PAGES_BEFORE_WE_STOP
527            {
528                log::info!("Stripe events: stopping, saw {pages_of_already_processed_events} pages of already-processed events");
529                break;
530            } else {
531                log::info!("Stripe events: retrieving next page");
532                event_pages = event_pages.next(&stripe_client).await?;
533            }
534        } else {
535            break;
536        }
537    }
538
539    log::info!("Stripe events: unprocessed {}", unprocessed_events.len());
540
541    // Sort all of the unprocessed events in ascending order, so we can handle them in the order they occurred.
542    unprocessed_events.sort_by(|a, b| a.created.cmp(&b.created).then_with(|| a.id.cmp(&b.id)));
543
544    for event in unprocessed_events {
545        let event_id = event.id.clone();
546        let processed_event_params = CreateProcessedStripeEventParams {
547            stripe_event_id: event.id.to_string(),
548            stripe_event_type: event_type_to_string(event.type_),
549            stripe_event_created_timestamp: event.created,
550        };
551
552        // If the event has happened too far in the past, we don't want to
553        // process it and risk overwriting other more-recent updates.
554        //
555        // 1 day was chosen arbitrarily. This could be made longer or shorter.
556        let one_day = Duration::from_secs(24 * 60 * 60);
557        let a_day_ago = Utc::now() - one_day;
558        if a_day_ago.timestamp() > event.created {
559            log::info!(
560                "Stripe events: event '{}' is more than {one_day:?} old, marking as processed",
561                event_id
562            );
563            app.db
564                .create_processed_stripe_event(&processed_event_params)
565                .await?;
566
567            return Ok(());
568        }
569
570        let process_result = match event.type_ {
571            EventType::CustomerCreated | EventType::CustomerUpdated => {
572                handle_customer_event(app, stripe_client, event).await
573            }
574            EventType::CustomerSubscriptionCreated
575            | EventType::CustomerSubscriptionUpdated
576            | EventType::CustomerSubscriptionPaused
577            | EventType::CustomerSubscriptionResumed
578            | EventType::CustomerSubscriptionDeleted => {
579                handle_customer_subscription_event(app, rpc_server, stripe_client, event).await
580            }
581            _ => Ok(()),
582        };
583
584        if let Some(()) = process_result
585            .with_context(|| format!("failed to process event {event_id} successfully"))
586            .log_err()
587        {
588            app.db
589                .create_processed_stripe_event(&processed_event_params)
590                .await?;
591        }
592    }
593
594    Ok(())
595}
596
597async fn handle_customer_event(
598    app: &Arc<AppState>,
599    _stripe_client: &stripe::Client,
600    event: stripe::Event,
601) -> anyhow::Result<()> {
602    let EventObject::Customer(customer) = event.data.object else {
603        bail!("unexpected event payload for {}", event.id);
604    };
605
606    log::info!("handling Stripe {} event: {}", event.type_, event.id);
607
608    let Some(email) = customer.email else {
609        log::info!("Stripe customer has no email: skipping");
610        return Ok(());
611    };
612
613    let Some(user) = app.db.get_user_by_email(&email).await? else {
614        log::info!("no user found for email: skipping");
615        return Ok(());
616    };
617
618    if let Some(existing_customer) = app
619        .db
620        .get_billing_customer_by_stripe_customer_id(&customer.id)
621        .await?
622    {
623        app.db
624            .update_billing_customer(
625                existing_customer.id,
626                &UpdateBillingCustomerParams {
627                    // For now we just leave the information as-is, as it is not
628                    // likely to change.
629                    ..Default::default()
630                },
631            )
632            .await?;
633    } else {
634        app.db
635            .create_billing_customer(&CreateBillingCustomerParams {
636                user_id: user.id,
637                stripe_customer_id: customer.id.to_string(),
638            })
639            .await?;
640    }
641
642    Ok(())
643}
644
645async fn handle_customer_subscription_event(
646    app: &Arc<AppState>,
647    rpc_server: &Arc<Server>,
648    stripe_client: &stripe::Client,
649    event: stripe::Event,
650) -> anyhow::Result<()> {
651    let EventObject::Subscription(subscription) = event.data.object else {
652        bail!("unexpected event payload for {}", event.id);
653    };
654
655    log::info!("handling Stripe {} event: {}", event.type_, event.id);
656
657    let billing_customer =
658        find_or_create_billing_customer(app, stripe_client, subscription.customer)
659            .await?
660            .ok_or_else(|| anyhow!("billing customer not found"))?;
661
662    if let Some(existing_subscription) = app
663        .db
664        .get_billing_subscription_by_stripe_subscription_id(&subscription.id)
665        .await?
666    {
667        app.db
668            .update_billing_subscription(
669                existing_subscription.id,
670                &UpdateBillingSubscriptionParams {
671                    billing_customer_id: ActiveValue::set(billing_customer.id),
672                    stripe_subscription_id: ActiveValue::set(subscription.id.to_string()),
673                    stripe_subscription_status: ActiveValue::set(subscription.status.into()),
674                    stripe_cancel_at: ActiveValue::set(
675                        subscription
676                            .cancel_at
677                            .and_then(|cancel_at| DateTime::from_timestamp(cancel_at, 0))
678                            .map(|time| time.naive_utc()),
679                    ),
680                    stripe_cancellation_reason: ActiveValue::set(
681                        subscription
682                            .cancellation_details
683                            .and_then(|details| details.reason)
684                            .map(|reason| reason.into()),
685                    ),
686                },
687            )
688            .await?;
689    } else {
690        // If the user already has an active billing subscription, ignore the
691        // event and return an `Ok` to signal that it was processed
692        // successfully.
693        //
694        // There is the possibility that this could cause us to not create a
695        // subscription in the following scenario:
696        //
697        //   1. User has an active subscription A
698        //   2. User cancels subscription A
699        //   3. User creates a new subscription B
700        //   4. We process the new subscription B before the cancellation of subscription A
701        //   5. User ends up with no subscriptions
702        //
703        // In theory this situation shouldn't arise as we try to process the events in the order they occur.
704        if app
705            .db
706            .has_active_billing_subscription(billing_customer.user_id)
707            .await?
708        {
709            log::info!(
710                "user {user_id} already has an active subscription, skipping creation of subscription {subscription_id}",
711                user_id = billing_customer.user_id,
712                subscription_id = subscription.id
713            );
714            return Ok(());
715        }
716
717        app.db
718            .create_billing_subscription(&CreateBillingSubscriptionParams {
719                billing_customer_id: billing_customer.id,
720                stripe_subscription_id: subscription.id.to_string(),
721                stripe_subscription_status: subscription.status.into(),
722            })
723            .await?;
724    }
725
726    // When the user's subscription changes, we want to refresh their LLM tokens
727    // to either grant/revoke access.
728    rpc_server
729        .refresh_llm_tokens_for_user(billing_customer.user_id)
730        .await;
731
732    Ok(())
733}
734
735#[derive(Debug, Deserialize)]
736struct GetMonthlySpendParams {
737    github_user_id: i32,
738}
739
740#[derive(Debug, Serialize)]
741struct GetMonthlySpendResponse {
742    monthly_free_tier_spend_in_cents: u32,
743    monthly_free_tier_allowance_in_cents: u32,
744    monthly_spend_in_cents: u32,
745}
746
747async fn get_monthly_spend(
748    Extension(app): Extension<Arc<AppState>>,
749    Query(params): Query<GetMonthlySpendParams>,
750) -> Result<Json<GetMonthlySpendResponse>> {
751    let user = app
752        .db
753        .get_user_by_github_user_id(params.github_user_id)
754        .await?
755        .ok_or_else(|| anyhow!("user not found"))?;
756
757    let Some(llm_db) = app.llm_db.clone() else {
758        return Err(Error::http(
759            StatusCode::NOT_IMPLEMENTED,
760            "LLM database not available".into(),
761        ));
762    };
763
764    let free_tier = user
765        .custom_llm_monthly_allowance_in_cents
766        .map(|allowance| Cents(allowance as u32))
767        .unwrap_or(FREE_TIER_MONTHLY_SPENDING_LIMIT);
768
769    let spending_for_month = llm_db
770        .get_user_spending_for_month(user.id, Utc::now())
771        .await?;
772
773    let free_tier_spend = Cents::min(spending_for_month, free_tier);
774    let monthly_spend = spending_for_month.saturating_sub(free_tier);
775
776    Ok(Json(GetMonthlySpendResponse {
777        monthly_free_tier_spend_in_cents: free_tier_spend.0,
778        monthly_free_tier_allowance_in_cents: free_tier.0,
779        monthly_spend_in_cents: monthly_spend.0,
780    }))
781}
782
783impl From<SubscriptionStatus> for StripeSubscriptionStatus {
784    fn from(value: SubscriptionStatus) -> Self {
785        match value {
786            SubscriptionStatus::Incomplete => Self::Incomplete,
787            SubscriptionStatus::IncompleteExpired => Self::IncompleteExpired,
788            SubscriptionStatus::Trialing => Self::Trialing,
789            SubscriptionStatus::Active => Self::Active,
790            SubscriptionStatus::PastDue => Self::PastDue,
791            SubscriptionStatus::Canceled => Self::Canceled,
792            SubscriptionStatus::Unpaid => Self::Unpaid,
793            SubscriptionStatus::Paused => Self::Paused,
794        }
795    }
796}
797
798impl From<CancellationDetailsReason> for StripeCancellationReason {
799    fn from(value: CancellationDetailsReason) -> Self {
800        match value {
801            CancellationDetailsReason::CancellationRequested => Self::CancellationRequested,
802            CancellationDetailsReason::PaymentDisputed => Self::PaymentDisputed,
803            CancellationDetailsReason::PaymentFailed => Self::PaymentFailed,
804        }
805    }
806}
807
808/// Finds or creates a billing customer using the provided customer.
809async fn find_or_create_billing_customer(
810    app: &Arc<AppState>,
811    stripe_client: &stripe::Client,
812    customer_or_id: Expandable<Customer>,
813) -> anyhow::Result<Option<billing_customer::Model>> {
814    let customer_id = match &customer_or_id {
815        Expandable::Id(id) => id,
816        Expandable::Object(customer) => customer.id.as_ref(),
817    };
818
819    // If we already have a billing customer record associated with the Stripe customer,
820    // there's nothing more we need to do.
821    if let Some(billing_customer) = app
822        .db
823        .get_billing_customer_by_stripe_customer_id(customer_id)
824        .await?
825    {
826        return Ok(Some(billing_customer));
827    }
828
829    // If all we have is a customer ID, resolve it to a full customer record by
830    // hitting the Stripe API.
831    let customer = match customer_or_id {
832        Expandable::Id(id) => Customer::retrieve(stripe_client, &id, &[]).await?,
833        Expandable::Object(customer) => *customer,
834    };
835
836    let Some(email) = customer.email else {
837        return Ok(None);
838    };
839
840    let Some(user) = app.db.get_user_by_email(&email).await? else {
841        return Ok(None);
842    };
843
844    let billing_customer = app
845        .db
846        .create_billing_customer(&CreateBillingCustomerParams {
847            user_id: user.id,
848            stripe_customer_id: customer.id.to_string(),
849        })
850        .await?;
851
852    Ok(Some(billing_customer))
853}
854
855const SYNC_LLM_USAGE_WITH_STRIPE_INTERVAL: Duration = Duration::from_secs(60);
856
857pub fn sync_llm_usage_with_stripe_periodically(app: Arc<AppState>) {
858    let Some(stripe_billing) = app.stripe_billing.clone() else {
859        log::warn!("failed to retrieve Stripe billing object");
860        return;
861    };
862    let Some(llm_db) = app.llm_db.clone() else {
863        log::warn!("failed to retrieve LLM database");
864        return;
865    };
866
867    let executor = app.executor.clone();
868    executor.spawn_detached({
869        let executor = executor.clone();
870        async move {
871            loop {
872                sync_with_stripe(&app, &llm_db, &stripe_billing)
873                    .await
874                    .context("failed to sync LLM usage to Stripe")
875                    .trace_err();
876                executor.sleep(SYNC_LLM_USAGE_WITH_STRIPE_INTERVAL).await;
877            }
878        }
879    });
880}
881
882async fn sync_with_stripe(
883    app: &Arc<AppState>,
884    llm_db: &Arc<LlmDatabase>,
885    stripe_billing: &Arc<StripeBilling>,
886) -> anyhow::Result<()> {
887    let events = llm_db.get_billing_events().await?;
888    let user_ids = events
889        .iter()
890        .map(|(event, _)| event.user_id)
891        .collect::<HashSet<UserId>>();
892    let stripe_subscriptions = app.db.get_active_billing_subscriptions(user_ids).await?;
893
894    for (event, model) in events {
895        let Some((stripe_db_customer, stripe_db_subscription)) =
896            stripe_subscriptions.get(&event.user_id)
897        else {
898            tracing::warn!(
899                user_id = event.user_id.0,
900                "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."
901            );
902            continue;
903        };
904        let stripe_subscription_id: stripe::SubscriptionId = stripe_db_subscription
905            .stripe_subscription_id
906            .parse()
907            .context("failed to parse stripe subscription id from db")?;
908        let stripe_customer_id: stripe::CustomerId = stripe_db_customer
909            .stripe_customer_id
910            .parse()
911            .context("failed to parse stripe customer id from db")?;
912
913        let stripe_model = stripe_billing.register_model(&model).await?;
914        stripe_billing
915            .subscribe_to_model(&stripe_subscription_id, &stripe_model)
916            .await?;
917        stripe_billing
918            .bill_model_usage(&stripe_customer_id, &stripe_model, &event)
919            .await?;
920        llm_db.consume_billing_event(event.id).await?;
921    }
922
923    Ok(())
924}