forklaunch 1.26.0

//! `whatsapp`: WhatsApp messages through the platform (AWS End User Messaging
//! Social). The service gets a `WhatsAppClient` built with
//! `createWhatsAppClient()` from the gateway settings, and a handler for the
//! `whatsapp.received` / `whatsapp.status` events the platform relays. No Meta
//! token or AWS credential reaches the service.

use anyhow::{Context, Result};

use super::{Capability, CapabilityEdit, add_named_imports};

pub(crate) static WHATSAPP: Capability = Capability {
    id: "whatsapp",
    resource_type: "whatsapp",
    summary: "WhatsApp template and session messages through the platform (no Meta token in the app)",
    registration_key: "WhatsAppClient",
    receives_events: true,
    add,
    remove,
};

const FRAMEWORK_HTTP: &str = "@forklaunch/core/http";
const CLIENT_FACTORY: &str = "createWhatsAppClient";
const SERVICES: &str = "@forklaunch/core/services";

/// The registration. `type<ReturnType<…>>()` keeps it to one import; the
/// gateway settings are the ones `ensure_gateway_wiring` declares.
const RUNTIME_BLOCK: &str = "const configInjector = createConfigInjector(SchemaValidator(), {
    WhatsAppClient: {
        lifetime: Lifetime.Singleton,
        type: type<ReturnType<typeof createWhatsAppClient>>(),
        factory: ({ PLATFORM_GATEWAY_URL, INSTANCE_ID, INSTANCE_HMAC_KEY }) =>
            createWhatsAppClient({
                gatewayUrl: PLATFORM_GATEWAY_URL,
                instanceId: INSTANCE_ID,
                hmacKey: INSTANCE_HMAC_KEY
            })
    }
});";

pub(crate) const HANDLER_STUB: &str = "import type {
  PlatformEvent,
  WhatsAppReceivedEvent,
  WhatsAppStatusEvent
} from '@forklaunch/core/http';

/**
 * WhatsApp events the platform relays to this service, already verified.
 *
 *   whatsapp.received  someone wrote to the business number. It opens the
 *                      24-hour window in which sendText is allowed for them.
 *   whatsapp.status    a sent message moved to sent / delivered / read / failed;
 *                      `messageId` is the one sendTemplate/sendText returned.
 *
 * Deliveries can repeat: dedupe on event.id. Throwing makes the platform
 * retry. Never log or store message text without classifying it: it is
 * whatever the person chose to write.
 */
export async function handle(event: PlatformEvent): Promise<void> {
  switch (event.type) {
    case 'whatsapp.received': {
      const message = event.data as unknown as WhatsAppReceivedEvent;
      // TODO: route the reply (message.from, message.text, message.type)
      void message;
      return;
    }
    case 'whatsapp.status': {
      const status = event.data as unknown as WhatsAppStatusEvent;
      // TODO: record delivery (status.messageId, status.status)
      void status;
      return;
    }
    default:
      return;
  }
}
";

fn core_package(edit: &CapabilityEdit) -> String {
    format!("@{}/core", edit.app_name)
}

fn add(edit: &mut CapabilityEdit) -> Result<()> {
    let core = core_package(edit);
    let path = edit.registrations_path();
    let before = edit
        .read(&path)?
        .with_context(|| format!("{path:?} not found"))?;
    // Merged into the file's imports from these sources, in its style.
    let mut text = add_named_imports(&before, FRAMEWORK_HTTP, &[CLIENT_FACTORY]);
    text = add_named_imports(&text, &core, &["type"]);
    text = add_named_imports(&text, SERVICES, &["getEnvVar"]);
    if text != before {
        edit.write(path, text);
    }
    // The gateway settings the factory reads go in with it
    // (`ensure_gateway_wiring` then finds them there).
    edit.inject_registration(
        "",
        FRAMEWORK_HTTP,
        Some(super::GATEWAY_ENV_BLOCK),
        Some(RUNTIME_BLOCK),
    )?;
    edit.ensure_platform_events("whatsapp", HANDLER_STUB)?;
    Ok(())
}

fn remove(edit: &mut CapabilityEdit) -> Result<()> {
    // createWhatsAppClient, and `type` unless something else still uses it,
    // go with the registration.
    edit.remove_registration(None, &[], &["WhatsAppClient"])
}

#[cfg(test)]
mod tests {
    use std::fs;

    use super::*;

    const REGISTRATIONS: &str = "import { number, optional, schemaValidator, SchemaValidator, string } from '@demo/core';
import { OpenTelemetryCollector } from '@forklaunch/core/http';
import { createConfigInjector, getEnvVar, Lifetime } from '@forklaunch/core/services';

const configInjector = createConfigInjector(SchemaValidator(), {
  SERVICE_METADATA: {
    lifetime: Lifetime.Singleton,
    type: { name: string, version: string },
    value: { name: 'billing', version: '0.1.0' }
  }
});

const environmentConfig = configInjector.chain({
  PORT: {
    lifetime: Lifetime.Singleton,
    type: number,
    value: Number(getEnvVar('PORT'))
  }
});

const runtimeDependencies = environmentConfig.chain({
  OtelCollector: {
    lifetime: Lifetime.Singleton,
    type: OpenTelemetryCollector,
    factory: () => new OpenTelemetryCollector('x', 'info')
  }
});

const serviceDependencies = runtimeDependencies.chain({});
";

    const SERVER: &str = "import { forklaunchExpress } from '@demo/core';
import { ci, tokens } from './bootstrapper';

const app = forklaunchExpress(schemaValidator, openTelemetryCollector);
app.use(billingRouter);
";

    fn scratch() -> (tempfile::TempDir, CapabilityEdit) {
        let dir = tempfile::tempdir().unwrap();
        let service = dir.path().join("src/modules/billing");
        fs::create_dir_all(&service).unwrap();
        fs::write(service.join("registrations.ts"), REGISTRATIONS).unwrap();
        fs::write(service.join("server.ts"), SERVER).unwrap();
        let edit = CapabilityEdit::new(
            dir.path(),
            "demo",
            "billing",
            &service,
            vec!["whatsapp".to_string()],
            vec!["whatsapp".to_string()],
        );
        (dir, edit)
    }

    #[test]
    fn add_registers_a_keyless_client_and_an_event_handler() {
        let (dir, mut edit) = scratch();
        add(&mut edit).unwrap();
        edit.ensure_gateway_wiring("whatsapp").unwrap();
        edit.commit().unwrap();
        let service = dir.path().join("src/modules/billing");
        let registrations = fs::read_to_string(service.join("registrations.ts")).unwrap();
        assert!(registrations.contains("WhatsAppClient:"), "{registrations}");
        assert!(registrations.contains("createWhatsAppClient({"));
        assert!(registrations.contains("hmacKey: INSTANCE_HMAC_KEY"));
        // Both framework imports kept; the factory merged into the http one.
        assert!(registrations.contains("OpenTelemetryCollector"));
        assert!(
            regex::Regex::new(r#"import \{[^}]*createConfigInjector[^}]*\} from '@forklaunch/core/services'"#)
                .unwrap()
                .is_match(&registrations),
            "{registrations}"
        );
        assert!(registrations.contains("PLATFORM_GATEWAY_URL:"));
        assert!(
            regex::Regex::new(r#"import \{[^}]*OpenTelemetryCollector[^}]*createWhatsAppClient[^}]*\} from '@forklaunch/core/http'"#)
                .unwrap()
                .is_match(&registrations),
            "{registrations}"
        );
        assert!(regex::Regex::new(r#"\btype\b[^}]*\} from '@demo/core'"#).unwrap().is_match(&registrations));
        // No vendor credential anywhere.
        assert!(!registrations.contains("WHATSAPP_TOKEN"));
        assert!(!registrations.contains("META_"));
        let handler = fs::read_to_string(service.join("api/platformEvents/whatsapp.ts")).unwrap();
        assert!(handler.contains("'whatsapp.received'"));
        assert!(handler.contains("'whatsapp.status'"));
        let index = fs::read_to_string(service.join("api/platformEvents/index.ts")).unwrap();
        assert!(index.contains("whatsapp: whatsappEvents"));
        let server = fs::read_to_string(service.join("server.ts")).unwrap();
        assert!(server.contains("app.use(platformEventsRouter);"));
    }

    #[test]
    fn remove_undoes_the_registration_and_imports() {
        let (dir, mut edit) = scratch();
        add(&mut edit).unwrap();
        edit.commit().unwrap();
        let service = dir.path().join("src/modules/billing");
        let mut edit = CapabilityEdit::new(dir.path(), "demo", "billing", &service, vec![], vec![]);
        remove(&mut edit).unwrap();
        edit.commit().unwrap();
        let registrations = fs::read_to_string(service.join("registrations.ts")).unwrap();
        assert!(!registrations.contains("WhatsAppClient"), "{registrations}");
        assert!(!registrations.contains("createWhatsAppClient"));
        assert!(registrations.contains("OpenTelemetryCollector"));
        assert!(!regex::Regex::new(r"\btype,").unwrap().is_match(&registrations), "{registrations}");
    }

    #[test]
    fn removing_the_last_event_feature_unmounts_the_events_router() {
        let (dir, mut edit) = scratch();
        add(&mut edit).unwrap();
        edit.commit().unwrap();
        let service = dir.path().join("src/modules/billing");
        let mut edit = CapabilityEdit::new(dir.path(), "demo", "billing", &service, vec![], vec![]);
        remove(&mut edit).unwrap();
        edit.remove_platform_events("whatsapp").unwrap();
        edit.release_gateway_wiring("whatsapp").unwrap();
        edit.commit().unwrap();
        assert_eq!(fs::read_to_string(service.join("server.ts")).unwrap(), SERVER);
        // The registration, its imports and the gateway settings add wrote
        // are gone: byte for byte the file it was.
        assert_eq!(
            fs::read_to_string(service.join("registrations.ts")).unwrap(),
            REGISTRATIONS
        );
        assert!(!service.join("api/platformEvents/whatsapp.ts").exists());
        assert!(!service.join("api/routes/platformEvents.routes.ts").exists());
    }

    #[test]
    fn type_import_is_kept_while_something_else_uses_it() {
        let text = "import { type, string } from '@demo/core';\nconst x = { t: type<unknown>() };\n";
        use crate::infra::in_place::binding_used as name_used_outside_imports;
        assert!(name_used_outside_imports(text, "type"));
        let text = "import {\n  type,\n  string\n} from '@demo/core';\nconst x = { t: string };\n";
        assert!(!name_used_outside_imports(text, "type"));
    }

    #[test]
    fn registered_with_events_and_its_resource_type() {
        let capability = super::super::find("whatsapp").expect("registered");
        assert_eq!(capability.resource_type, "whatsapp");
        assert_eq!(capability.registration_key, "WhatsAppClient");
        assert!(capability.receives_events);
    }
}