| name | native-trigger |
| description | Guidance for adding native trigger services to Windmill. Use when implementing or modifying native trigger integrations across the backend and frontend. |
Skill: Adding Native Trigger Services
This skill provides comprehensive guidance for adding new native trigger services to Windmill. Native triggers allow external services (like Nextcloud, Google Drive, etc.) to trigger Windmill scripts/flows via webhooks or push notifications.
Architecture Overview
The native trigger system consists of:
- Database Layer - PostgreSQL tables and enum types
- Backend Rust Implementation - Core trait, handlers, and service modules in the
windmill-native-triggers crate
- Frontend Svelte Components - Configuration forms and UI components
Key Files
| Component | Path |
|---|
Core module with External trait | backend/windmill-native-triggers/src/lib.rs |
| Generic CRUD handlers | backend/windmill-native-triggers/src/handler.rs |
| Background sync logic | backend/windmill-native-triggers/src/sync.rs |
| OAuth/workspace integration | backend/windmill-native-triggers/src/workspace_integrations.rs |
| Re-export shim (windmill-api) | backend/windmill-api/src/native_triggers/mod.rs |
| TriggerKind enum | backend/windmill-common/src/triggers.rs |
| JobTriggerKind enum | backend/windmill-common/src/jobs.rs |
| Frontend service registry | frontend/src/lib/components/triggers/native/utils.ts |
| Frontend trigger utilities | frontend/src/lib/components/triggers/utils.ts |
| Trigger badges (icons + counts) | frontend/src/lib/components/graph/renderers/triggers/TriggersBadge.svelte |
| Workspace integrations UI | frontend/src/lib/components/workspaceSettings/WorkspaceIntegrations.svelte |
| OAuth config form component | frontend/src/lib/components/workspaceSettings/OAuthClientConfig.svelte |
| OpenAPI spec | backend/windmill-api/openapi.yaml |
| Reference: Nextcloud module | backend/windmill-native-triggers/src/nextcloud/ |
| Reference: Google module | backend/windmill-native-triggers/src/google/ |
Crate Structure
The native trigger code lives in the windmill-native-triggers crate (backend/windmill-native-triggers/). The windmill-api crate re-exports everything via a shim:
pub use windmill_native_triggers::*;
All new service modules go in backend/windmill-native-triggers/src/.
Core Concepts
The External Trait
Every native trigger service implements the External trait defined in lib.rs:
#[async_trait]
pub trait External: Send + Sync + 'static {
type ServiceConfig: Debug + DeserializeOwned + Serialize + Send + Sync;
type TriggerData: Debug + Serialize + Send + Sync;
type OAuthData: DeserializeOwned + Serialize + Clone + Send + Sync;
type CreateResponse: DeserializeOwned + Send + Sync;
const SUPPORT_WEBHOOK: bool;
const SERVICE_NAME: ServiceName;
const DISPLAY_NAME: &'static str;
const TOKEN_ENDPOINT: &'static str;
const REFRESH_ENDPOINT: &'static str;
const AUTH_ENDPOINT: &'static str;
async fn create(&self, w_id, oauth_data, webhook_token, data, db, tx) -> Result<Self::CreateResponse>;
async fn update(&self, w_id, oauth_data, external_id, webhook_token, data, db, tx) -> Result<serde_json::Value>;
async fn get(&self, w_id, oauth_data, external_id, db, tx) -> Result<Self::TriggerData>;
async fn delete(&self, w_id, oauth_data, external_id, db, tx) -> Result<()>;
async fn exists(&self, w_id, oauth_data, external_id, db, tx) -> Result<bool>;
async fn maintain_triggers(&self, db, workspace_id, triggers, oauth_data, synced, errors);
fn external_id_and_metadata_from_response(&self, resp) -> (String, Option<serde_json::Value>);
async fn prepare_webhook(&self, db, w_id, headers, body, script_path, is_flow) -> Result<PushArgsOwned>;
fn service_config_from_create_response(&self, data, resp) -> Option<serde_json::Value>;
fn additional_routes(&self) -> axum::Router;
async fn http_client_request<T, B>(&self, url, method, workspace_id, tx, db, headers, body) -> Result<T>;
}
Key design points:
update() returns serde_json::Value - the resolved service_config to store. Each service is responsible for building the final config.
maintain_triggers() - periodic background maintenance. Each service implements its own strategy (Nextcloud: reconcile with external state; Google: renew expiring channels).
- No
list_all() in the trait - services that need it (Nextcloud) implement it privately; services that don't (Google) use different maintenance strategies.
- No
get_external_id_from_trigger_data() or extract_service_config_from_trigger_data() - removed in favor of the maintain_triggers pattern.
Create Lifecycle: Two Paths
The create_native_trigger handler in handler.rs supports two creation flows, controlled by service_config_from_create_response():
Path A: Short (Google pattern) - service_config_from_create_response() returns Some(config):
create() registers on external service
external_id_and_metadata_from_response() extracts the ID
service_config_from_create_response() builds the config directly from input data + response metadata
- Stores trigger in DB -- done, no extra round-trip
Use this when the external_id is known before the create call (e.g., Google generates the channel_id as a UUID upfront and includes it in the webhook URL).
Path B: Long (Nextcloud pattern) - service_config_from_create_response() returns None (default):
create() registers on external service (webhook URL has no external_id yet)
external_id_and_metadata_from_response() extracts the ID
update() is called to fix the webhook URL with the now-known external_id
update() returns the resolved service_config
- Stores trigger in DB
Use this when the external_id is assigned by the remote service and the webhook URL needs to be corrected after creation.
OAuth Token Storage (Three-Table Pattern)
OAuth tokens are stored across three tables, NOT in workspace_integrations.oauth_data directly:
| Table | What's Stored |
|---|
workspace_integrations | oauth_data JSON with base_url, client_id, client_secret, instance_shared flag; resource_path pointing to the variable |
variable | Encrypted access_token (at the path stored in resource_path), linked to account via account column |
account | refresh_token, keyed by workspace_id + client (service name) + is_workspace_integration = true |
The decrypt_oauth_data() function in lib.rs assembles these into a unified struct:
pub struct OAuthConfig {
pub base_url: String,
pub access_token: String,
pub refresh_token: Option<String>,
pub client_id: String,
pub client_secret: String,
}
Instance-level sharing: when oauth_data.instance_shared == true, client_id and client_secret are read from global settings instead of workspace_integrations.
URL Resolution
The resolve_endpoint() helper handles both absolute and relative OAuth URLs:
pub fn resolve_endpoint(base_url: &str, endpoint: &str) -> String {
if endpoint.starts_with("http://") || endpoint.starts_with("https://") {
endpoint.to_string()
} else {
format!("{}{}", base_url, endpoint)
}
}
ServiceName Methods
ServiceName is the central registry enum. Each variant must implement these match arms:
| Method | Purpose |
|---|
as_str() | Lowercase identifier (e.g., "google") |
as_trigger_kind() | Maps to TriggerKind enum |
as_job_trigger_kind() | Maps to JobTriggerKind enum |
token_endpoint() | OAuth token endpoint (relative or absolute) |
auth_endpoint() | OAuth authorization endpoint |
oauth_scopes() | Space-separated OAuth scopes |
resource_type() | Resource type for token storage (e.g., "gworkspace") |
extra_auth_params() | Extra OAuth params (e.g., Google needs access_type=offline, prompt=consent) |
integration_service() | Maps to the workspace integration service (usually *self) |
TryFrom<String> | Parse from string |
Display | Delegates to as_str() |
Step-by-Step Implementation Guide
Step 1: Database Migration
Create a new migration file: backend/migrations/YYYYMMDDHHMMSS_newservice_trigger.up.sql
ALTER TYPE native_trigger_service ADD VALUE IF NOT EXISTS 'newservice';
ALTER TYPE TRIGGER_KIND ADD VALUE IF NOT EXISTS 'newservice';
ALTER TYPE job_trigger_kind ADD VALUE IF NOT EXISTS 'newservice';
Also create the corresponding down migration.
Step 2: Update windmill-common Enums
backend/windmill-common/src/triggers.rs
Add variant to TriggerKind enum, and update to_key() and fmt() implementations.
backend/windmill-common/src/jobs.rs
Add variant to JobTriggerKind enum and update the Display implementation.
Step 3: Backend Service Module
Create a new directory: backend/windmill-native-triggers/src/newservice/
mod.rs - Type Definitions
use serde::{Deserialize, Serialize};
pub mod external;
#[derive(Debug, Clone, Deserialize, Serialize)]
pub struct NewServiceOAuthData {
pub base_url: String,
pub access_token: String,
pub refresh_token: Option<String>,
}
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct NewServiceConfig {
pub folder_path: String,
pub file_filter: Option<String>,
}
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct NewServiceTriggerData {
pub folder_path: String,
pub file_filter: Option<String>,
}
#[derive(Debug, Deserialize)]
pub struct CreateTriggerResponse {
pub id: String,
}
#[derive(Copy, Clone)]
pub struct NewService;
external.rs - External Trait Implementation
use async_trait::async_trait;
use reqwest::Method;
use sqlx::PgConnection;
use std::collections::HashMap;
use windmill_common::{
error::{Error, Result},
BASE_URL, DB,
};
use crate::{
generate_webhook_service_url, External, NativeTrigger, NativeTriggerData, ServiceName,
sync::{SyncError, TriggerSyncInfo},
};
use super::{NewService, NewServiceConfig, NewServiceOAuthData, NewServiceTriggerData, CreateTriggerResponse};
#[async_trait]
impl External for NewService {
type ServiceConfig = NewServiceConfig;
type TriggerData = NewServiceTriggerData;
type OAuthData = NewServiceOAuthData;
type CreateResponse = CreateTriggerResponse;
const SERVICE_NAME: ServiceName = ServiceName::NewService;
const DISPLAY_NAME: &'static str = "New Service";
const SUPPORT_WEBHOOK: bool = true;
const TOKEN_ENDPOINT: &'static str = "/oauth/token";
const REFRESH_ENDPOINT: &'static str = "/oauth/token";
const AUTH_ENDPOINT: &'static str = "/oauth/authorize";
async fn create(
&self,
w_id: &str,
oauth_data: &Self::OAuthData,
webhook_token: &str,
data: &NativeTriggerData<Self::ServiceConfig>,
db: &DB,
tx: &mut PgConnection,
) -> Result<Self::CreateResponse> {
let base_url = &*BASE_URL.read().await;
let webhook_url = generate_webhook_service_url(
base_url, w_id, &data.script_path, data.is_flow,
None, Self::SERVICE_NAME, webhook_token,
);
let url = format!("{}/api/webhooks/create", oauth_data.base_url);
let payload = serde_json::json!({
"callback_url": webhook_url,
"folder_path": data.service_config.folder_path,
});
let response: CreateTriggerResponse = self
.http_client_request(&url, Method::POST, w_id, tx, db, None, Some(&payload))
.await?;
Ok(response)
}
async fn update(
&self,
w_id: &str,
oauth_data: &Self::OAuthData,
external_id: &str,
webhook_token: &str,
data: &NativeTriggerData<Self::ServiceConfig>,
db: &DB,
tx: &mut PgConnection,
) -> Result<serde_json::Value> {
let base_url = &*BASE_URL.read().await;
let webhook_url = generate_webhook_service_url(
base_url, w_id, &data.script_path, data.is_flow,
Some(external_id), Self::SERVICE_NAME, webhook_token,
);
let url = format!("{}/api/webhooks/{}", oauth_data.base_url, external_id);
let payload = serde_json::json!({
"callback_url": webhook_url,
"folder_path": data.service_config.folder_path,
});
let _: serde_json::Value = self
.http_client_request(&url, Method::PUT, w_id, tx, db, None, Some(&payload))
.await?;
let trigger_data = self.get(w_id, oauth_data, external_id, db, tx).await?;
serde_json::to_value(&trigger_data)
.map_err(|e| Error::InternalErr(format!("Failed to serialize trigger data: {}", e)))
}
async fn get(
&self,
w_id: &str,
oauth_data: &Self::OAuthData,
external_id: &str,
db: &DB,
tx: &mut PgConnection,
) -> Result<Self::TriggerData> {
let url = format!("{}/api/webhooks/{}", oauth_data.base_url, external_id);
self.http_client_request::<_, ()>(&url, Method::GET, w_id, tx, db, None, None).await
}
async fn delete(
&self,
w_id: &str,
oauth_data: &Self::OAuthData,
external_id: &str,
db: &DB,
tx: &mut PgConnection,
) -> Result<()> {
let url = format!("{}/api/webhooks/{}", oauth_data.base_url, external_id);
let _: serde_json::Value = self
.http_client_request::<_, ()>(&url, Method::DELETE, w_id, tx, db, None, None)
.await
.or_else(|e| match &e {
Error::InternalErr(msg) if msg.contains("404") => Ok(serde_json::Value::Null),
_ => Err(e),
})?;
Ok(())
}
async fn exists(
&self,
w_id: &str,
oauth_data: &Self::OAuthData,
external_id: &str,
db: &DB,
tx: &mut PgConnection,
) -> Result<bool> {
match self.get(w_id, oauth_data, external_id, db, tx).await {
Ok(_) => Ok(true),
Err(Error::NotFound(_)) => Ok(false),
Err(e) => Err(e),
}
}
async fn maintain_triggers(
&self,
db: &DB,
workspace_id: &str,
triggers: &[NativeTrigger],
oauth_data: &Self::OAuthData,
synced: &mut Vec<TriggerSyncInfo>,
errors: &mut Vec<SyncError>,
) {
let external_triggers = match self.list_all(workspace_id, oauth_data, db).await {
Ok(triggers) => triggers,
Err(e) => {
errors.push(SyncError {
resource_path: format!("workspace:{}", workspace_id),
error_message: format!("Failed to list triggers: {}", e),
error_type: "api_error".to_string(),
});
return;
}
};
let external_pairs: Vec<(String, serde_json::Value)> = external_triggers
.into_iter()
.map(|t| (t.id.clone(), serde_json::to_value(&t).unwrap_or_default()))
.collect();
crate::sync::reconcile_with_external_state(
db, workspace_id, Self::SERVICE_NAME, triggers, &external_pairs, synced, errors,
).await;
}
fn external_id_and_metadata_from_response(
&self,
resp: &Self::CreateResponse,
) -> (String, Option<serde_json::Value>) {
(resp.id.clone(), None)
}
}
impl NewService {
async fn list_all(
&self,
w_id: &str,
oauth_data: &<Self as External>::OAuthData,
db: &DB,
) -> Result<Vec<<Self as External>::TriggerData>> {
todo!()
}
}
Step 4: Update lib.rs Registry
In backend/windmill-native-triggers/src/lib.rs:
#[cfg(feature = "native_trigger")]
pub mod newservice;
pub enum ServiceName {
Nextcloud,
Google,
NewService,
}
Step 5: Update handler.rs Routes
In backend/windmill-native-triggers/src/handler.rs:
pub fn generate_native_trigger_routers() -> Router {
#[cfg(feature = "native_trigger")]
{
use crate::newservice::NewService;
return router
.nest("/nextcloud", service_routes(NextCloud))
.nest("/google", service_routes(Google))
.nest("/newservice", service_routes(NewService));
}
}
Step 6: Update sync.rs
In backend/windmill-native-triggers/src/sync.rs:
pub async fn sync_all_triggers(db: &DB) -> Result<BackgroundSyncResult> {
#[cfg(feature = "native_trigger")]
{
use crate::newservice::NewService;
let (service_name, result) = sync_service_triggers(db, NewService).await;
total_synced += result.synced_triggers.len();
total_errors += result.errors.len();
service_results.insert(service_name, result);
}
}
Step 7: Frontend Service Registry
In frontend/src/lib/components/triggers/native/utils.ts:
Add to NATIVE_TRIGGER_SERVICES, getTriggerIconName(), and getServiceIcon().
Step 8: Frontend Trigger Form Component
Create: frontend/src/lib/components/triggers/native/services/newservice/NewServiceTriggerForm.svelte
Step 9: Frontend Icon Component
Create: frontend/src/lib/components/icons/NewServiceIcon.svelte
Step 10: Update NativeTriggerEditor
Check frontend/src/lib/components/triggers/native/NativeTriggerEditor.svelte to ensure it dynamically loads form components based on service name.
Step 11: Workspace Integration UI
Add your service to the supportedServices map in frontend/src/lib/components/workspaceSettings/WorkspaceIntegrations.svelte:
const supportedServices: Record<string, ServiceConfig> = {
newservice: {
name: 'newservice',
displayName: 'New Service',
description: 'Connect to New Service for triggers',
icon: NewServiceIcon,
docsUrl: 'https://www.windmill.dev/docs/integrations/newservice',
requiresBaseUrl: false,
setupInstructions: [
'Step 1: Create an OAuth app on the service',
'Step 2: Configure the redirect URI shown below',
'Step 3: Enter the client credentials below'
]
}
}
Step 12: Update frontend/src/lib/components/triggers/utils.ts
Update ALL of these maps/functions:
triggerIconMap - import and add icon
triggerDisplayNamesMap - add display name
triggerTypeOrder in sortTriggers() - add type
getLightConfig() - add case for your service
getTriggerLabel() - add case for your service
jobTriggerKinds - add to array
countPropertyMap - add count property
triggerSaveFunctions - add save function
Step 13: Update TriggersBadge Component
In frontend/src/lib/components/graph/renderers/triggers/TriggersBadge.svelte:
- Import the icon
- Add to
baseConfig with countKey (the dynamic availableNativeServices loop does NOT set countKey)
- Add to the
allTypes array
Step 14: Update TriggersWrapper.svelte
In frontend/src/lib/components/triggers/TriggersWrapper.svelte:
Add a {:else if selectedTrigger.type === 'yourservice'} case that renders <NativeTriggersPanel service="yourservice" ...> with the same props pattern as the existing native trigger cases (e.g., nextcloud).
Step 15: Update AddTriggersButton.svelte
In frontend/src/lib/components/triggers/AddTriggersButton.svelte:
- Add
yourserviceAvailable state variable
- Add
setYourserviceState() async function using isServiceAvailable('yourservice', $workspaceStore!)
- Call it at module level
- Add a dropdown entry to
addTriggerItems with hidden: !yourserviceAvailable
Step 16: Update TriggersEditor.svelte Delete Handling
In frontend/src/lib/components/triggers/TriggersEditor.svelte:
Add your service to the nativeTriggerServices map in deleteDeployedTrigger(). Native triggers use NativeTriggerService.deleteNativeTrigger({ workspace, serviceName, externalId }) instead of the standard path-based delete.
Step 17: Update getUsedTriggers for Sidebar Visibility
The sidebar (frontend/src/lib/components/sidebar/SidebarContent.svelte) shows native-trigger links only if $usedTriggerKinds includes the service — without this, your trigger page will never appear in the nav bar even when triggers exist.
- Backend — add
{service}_used: bool to the UsedTriggers struct and SELECT in backend/windmill-api-workspaces/src/workspaces.rs::get_used_triggers():
EXISTS(SELECT 1 FROM native_trigger WHERE workspace_id = $1 AND service_name = '{service}'::native_trigger_service) AS "{service}_used!"
- OpenAPI — add
{service}_used: boolean to the response schema for GET /w/{workspace}/workspaces/used_triggers (under both properties and required).
- Layout — in
frontend/src/routes/(root)/(logged)/+layout.svelte::loadUsedTriggerKinds(), destructure {service}_used and push '{service}' to usedKinds.
Step 18: Update OpenAPI Spec and Regenerate Types
Add to JobTriggerKind enum in backend/windmill-api/openapi.yaml, then:
cd frontend && npm run generate-backend-client
Special Patterns
Unified Service with trigger_type (Google Pattern)
When a single service handles multiple trigger types (e.g., Google Drive + Calendar share OAuth and API patterns), use a single ServiceName variant with a discriminator field:
pub enum GoogleTriggerType { Drive, Calendar }
pub struct GoogleServiceConfig {
pub trigger_type: GoogleTriggerType,
pub resource_id: Option<String>,
pub resource_name: Option<String>,
pub calendar_id: Option<String>,
pub calendar_name: Option<String>,
pub google_resource_id: Option<String>,
pub expiration: Option<String>,
}
Branch in trait methods based on trigger_type. Frontend uses a ToggleButtonGroup to switch between types. This keeps the codebase simpler (one service, one OAuth flow, one set of routes).
See backend/windmill-native-triggers/src/google/ for the reference implementation.
Skipping update+get After Create (Google Pattern)
Override service_config_from_create_response() to return Some(config) when the external_id is known before the create call:
fn service_config_from_create_response(
&self,
data: &NativeTriggerData<Self::ServiceConfig>,
resp: &Self::CreateResponse,
) -> Option<serde_json::Value> {
let mut config = data.service_config.clone();
config.google_resource_id = Some(resp.resource_id.clone());
config.expiration = Some(resp.expiration.clone());
Some(serde_json::to_value(&config).unwrap())
}
Services with Absolute OAuth Endpoints (Google)
Unlike self-hosted services where OAuth endpoints are relative paths appended to base_url, services like Google have absolute URLs:
ServiceName::Nextcloud => "/apps/oauth2/api/v1/token",
ServiceName::Google => "https://oauth2.googleapis.com/token",
The resolve_endpoint() function handles both. For services with absolute endpoints:
base_url can be empty
requiresBaseUrl: false in the frontend workspace integration config
- Add
extra_auth_params() if needed (Google requires access_type=offline and prompt=consent)
Channel-Based Push Notifications with Renewal (Google Pattern)
For services using expiring watch channels instead of persistent webhooks:
- Store expiration in
service_config (as part of ServiceConfig)
- In
maintain_triggers(), implement renewal logic instead of using reconcile_with_external_state():
async fn maintain_triggers(&self, db, workspace_id, triggers, oauth_data, synced, errors) {
for trigger in triggers {
if should_renew_channel(trigger) {
self.renew_channel(db, trigger, oauth_data).await;
}
}
}
- Renewal: best-effort stop old channel, create new one with same external_id, update service_config with new expiration
- Google example: Drive channels expire in 24h (renew when <1h left), Calendar channels expire in 7 days (renew when <1 day left)
reconcile_with_external_state (Nextcloud Pattern)
The reusable function in sync.rs compares external triggers with DB state:
- Triggers missing externally: sets error "Trigger no longer exists on external service"
- Triggers present externally: clears errors, updates service_config if it differs
Usage in maintain_triggers():
let external_pairs: Vec<(String, serde_json::Value)> = ;
crate::sync::reconcile_with_external_state(
db, workspace_id, Self::SERVICE_NAME, triggers, &external_pairs, synced, errors,
).await;
Webhook Payload Processing
Override prepare_webhook() to parse service-specific payloads into script/flow args:
async fn prepare_webhook(&self, db, w_id, headers, body, script_path, is_flow) -> Result<PushArgsOwned> {
let mut args = HashMap::new();
args.insert("event_type".to_string(), Box::new(headers.get("x-event-type").cloned()) as _);
args.insert("payload".to_string(), Box::new(serde_json::from_str::<serde_json::Value>(&body)?) as _);
Ok(PushArgsOwned { extra: None, args })
}
Then register in prepare_native_trigger_args() in lib.rs:
pub async fn prepare_native_trigger_args(service_name, db, w_id, headers, body) -> Result<Option<PushArgsOwned>> {
match service_name {
ServiceName::Google => { Ok(Some(args)) }
ServiceName::NewService => { Ok(Some(args)) }
ServiceName::Nextcloud => Ok(None),
}
}
Instance-Level OAuth Credentials
When workspace_integrations.oauth_data.instance_shared == true, decrypt_oauth_data() reads client_id and client_secret from instance-level global settings instead of workspace-level. This allows admins to share OAuth app credentials across workspaces.
The frontend handles this via the generate_instance_connect_url endpoint in workspace_integrations.rs.
Testing Checklist
Reference Implementations
Nextcloud (Self-Hosted, Update+Get Pattern)
| File | Purpose |
|---|
nextcloud/mod.rs | Types: NextCloudOAuthData, NextcloudServiceConfig, NextCloudTriggerData |
nextcloud/external.rs | External trait: uses update+get pattern, reconcile_with_external_state for sync |
nextcloud/routes.rs | Additional route: GET /events |
Key patterns: relative OAuth endpoints, base_url required, list_all + reconcile for sync, update returns JSON from get().
Google (Cloud, Unified Service, Short Create)
| File | Purpose |
|---|
google/mod.rs | Types: GoogleServiceConfig with trigger_type discriminator, GoogleTriggerType enum |
google/external.rs | External trait: overrides service_config_from_create_response, channel renewal for sync |
google/routes.rs | Additional routes: GET /calendars, GET /drive/files, GET /drive/shared_drives |
Key patterns: absolute OAuth endpoints, empty base_url, trigger_type for Drive/Calendar, expiring watch channels with renewal, service_config_from_create_response skips update+get, get() reconstructs data from stored service_config (no external "get channel" API).