use std::collections::HashSet;
use std::sync::atomic::Ordering;
use std::sync::{Arc, Mutex as StdMutex};
use mobius::backend::checkpoint::CheckpointStore;
use mobius::backend::model::provider::{ProviderAuth, provider};
use uuid::Uuid;
use crate::Error;
use crate::config::{ChatSpec, GatewayConfig};
use crate::provider_catalog::{configured_model_choices, credential_is_configured};
use crate::wire::{
AgentComposition, ProviderConfig, ProviderEndpointAuth, ProviderTint, ReadyPayload,
ServerFrame, ServerMessage,
};
use super::session::ProviderRefresh;
use super::{GatewayHost, Rejection, gateway_ready, internal, invalid_config};
impl GatewayHost {
pub(crate) async fn configure_default_agent(
&self,
expected_revision: u64,
config: AgentComposition,
) -> std::result::Result<ReadyPayload, Rejection> {
let state = self.state.lock().await;
{
let mut current = state
.config
.lock()
.map_err(|_| internal("gateway configuration lock is poisoned"))?;
let models = configured_model_choices(¤t, &state.store, &state.credentials)
.map_err(internal)?;
crate::middleware_manifest::validate_choices(&config.middleware, &models)
.map_err(invalid_config)?;
let next = current
.replacing_default_agent(expected_revision, config)
.map_err(invalid_config)?;
state.store.save(&next).map_err(internal)?;
*current = next;
}
let payload = gateway_ready(&state).await?;
let _ = self.events.send(ServerFrame::new(ServerMessage::Ready {
payload: payload.clone(),
}));
Ok(payload)
}
pub(crate) async fn set_credential(
&self,
instance: String,
provider_id: String,
api_key: String,
base_url: Option<String>,
) -> std::result::Result<(), Rejection> {
let (base_url, configured) = {
let state = self.state.lock().await;
let definition = provider(&provider_id).map_err(invalid_config)?;
let base_url = if definition.configurable_base_url() {
base_url.or_else(|| definition.default_base_url().map(str::to_owned))
} else {
base_url
};
definition
.validate_base_url(base_url.as_deref())
.map_err(invalid_config)?;
state
.credentials
.set(&instance, &provider_id, &api_key, base_url.as_deref())
.map_err(invalid_config)?;
let configured = state
.config
.lock()
.map_err(|_| internal("gateway configuration lock is poisoned"))?
.configured_providers
.get(&instance)
.filter(|configured| {
let configured_base_url = if definition.configurable_base_url() {
configured
.selection
.base_url
.as_deref()
.or_else(|| definition.default_base_url())
} else {
None
};
configured.selection.provider == provider_id.as_str()
&& configured.selection.endpoint_auth
== ProviderEndpointAuth::Credentialless
&& configured_base_url == base_url.as_deref()
})
.cloned();
(base_url, configured)
};
if let Some(configured) = configured {
let mut selection = configured.selection;
selection.endpoint_auth = ProviderEndpointAuth::ProviderDefault;
self.register_provider(
selection,
configured.label,
configured.tint,
configured.model_ids,
configured.reasoning_efforts,
true,
)
.await?;
return Ok(());
}
self.refresh_provider_sessions(ProviderRefresh::Instance { instance, base_url })
.await
}
pub(crate) async fn start_provider_login(
&self,
request_id: String,
provider_id: String,
) -> std::result::Result<(), Rejection> {
let definition = provider(&provider_id).map_err(invalid_config)?;
let ProviderAuth::Browser(auth) = definition.auth() else {
return Err(Rejection {
code: "invalid_provider_auth",
message: "the selected provider uses an API key".into(),
fatal: false,
});
};
if !auth.supports_device_login() {
return Err(Rejection {
code: "device_login_unavailable",
message: "the selected provider does not support device-code login".into(),
fatal: false,
});
}
let (login_guard, path) = {
let state = self.state.lock().await;
(
Arc::clone(&state.provider_login),
state.store.provider_auth_path(),
)
};
let login_id = Uuid::new_v4().to_string();
reserve_provider_login(&login_guard, &login_id)?;
let login = match auth.start_device().await {
Ok(login) => login,
Err(error) => {
release_provider_login(&login_guard, &login_id)?;
return Err(internal(error));
}
};
self.broadcast(ServerMessage::ProviderLoginStarted {
request_id: request_id.clone(),
login_id: login_id.clone(),
provider: provider_id.clone(),
verification_url: login.verification_url().into(),
user_code: login.user_code().into(),
});
let gateway = self.clone();
tokio::spawn(async move {
let result = login
.complete(path)
.await
.map_err(|error| error.to_string());
gateway
.finish_provider_login(request_id, login_id, provider_id, result)
.await;
});
Ok(())
}
async fn finish_provider_login(
&self,
request_id: String,
login_id: String,
provider: String,
result: std::result::Result<(), String>,
) {
let login_guard = Arc::clone(&self.state.lock().await.provider_login);
match release_provider_login(&login_guard, &login_id) {
Ok(true) => {}
Ok(false) => return,
Err(rejection) => {
self.broadcast(ServerMessage::Error {
code: rejection.code.into(),
message: rejection.message,
fatal: rejection.fatal,
});
return;
}
}
if let Err(message) = result {
self.broadcast(ServerMessage::Rejected {
request_id,
code: "provider_login_failed".into(),
message,
fatal: false,
});
return;
}
let refresh = self
.refresh_provider_sessions(ProviderRefresh::Provider(provider.clone()))
.await;
self.broadcast(ServerMessage::ProviderLoginFinished {
request_id,
login_id,
provider,
});
if let Err(rejection) = refresh {
self.broadcast(ServerMessage::Error {
code: rejection.code.into(),
message: rejection.message,
fatal: rejection.fatal,
});
}
}
async fn refresh_provider_sessions(
&self,
scope: ProviderRefresh,
) -> std::result::Result<(), Rejection> {
let sessions = self
.state
.lock()
.await
.sessions
.values()
.cloned()
.collect::<Vec<_>>();
let mut failure = None;
for host in sessions {
if let Err(rejection) = host.refresh_provider(scope.clone()).await {
failure.get_or_insert(rejection);
}
}
failure.map_or(Ok(()), Err)
}
fn broadcast(&self, message: ServerMessage) {
let _ = self.events.send(ServerFrame::new(message));
}
pub(crate) async fn register_provider(
&self,
selection: ProviderConfig,
label: String,
tint: ProviderTint,
model_ids: Vec<String>,
reasoning_efforts: Vec<String>,
replace_existing_selections: bool,
) -> std::result::Result<ReadyPayload, Rejection> {
let mut state = self.state.lock().await;
let mutation_gate = Arc::clone(&state.session_mutations);
let _mutation = mutation_gate.write_owned().await;
if !credential_is_configured(&selection, &state.store, &state.credentials)
.map_err(invalid_config)?
{
return Err(invalid_config(Error::Config(format!(
"provider `{}` is not configured on this gateway",
selection.provider
))));
}
let current = state
.config
.lock()
.map_err(|_| internal("gateway configuration lock is poisoned"))?
.clone();
let next = provider_registration(
¤t,
&selection,
&label,
tint,
&model_ids,
&reasoning_efforts,
replace_existing_selections,
)
.map_err(invalid_config)?;
let mut replacements = Vec::new();
let mut migrations = Vec::new();
let mut target_epoch = state.provider_epoch.load(Ordering::Acquire);
if current.configured_providers != next.configured_providers {
target_epoch = target_epoch
.checked_add(1)
.ok_or_else(|| internal("provider catalog epoch overflow"))?;
}
if replace_existing_selections {
let residents = provider_cutover_residents(&mut state).await?;
let resident_ids = residents
.iter()
.map(|resident| resident.session_id.clone())
.collect::<HashSet<_>>();
migrations = residents
.iter()
.filter(|resident| {
resident.status.provider_epoch != target_epoch
|| (resident.status.selection.instance == selection.instance
&& resident.status.selection != selection)
})
.map(|resident| (resident.session_id.clone(), resident.host.clone()))
.collect();
replacements =
provider_checkpoint_replacements(&state, &selection, &next, &resident_ids)
.await
.map_err(internal)?;
if current == next && replacements.is_empty() && migrations.is_empty() {
return gateway_ready(&state).await;
}
if residents.iter().any(|resident| !resident.status.idle) {
return Err(Rejection {
code: "agent_busy",
message: "finish or interrupt active turns before changing gateway providers"
.into(),
fatal: false,
});
}
save_provider_checkpoint_replacements(&state.checkpoints, &replacements)
.await
.map_err(internal)?;
}
let commit = commit_provider_registration(
&state,
&selection,
&label,
tint,
&model_ids,
&reasoning_efforts,
replace_existing_selections,
);
let catalog_changed = match commit {
Ok(catalog_changed) => catalog_changed,
Err(error) => {
if replace_existing_selections
&& let Err(rollback) =
rollback_provider_checkpoints(&state.checkpoints, &replacements).await
{
return Err(internal(format!(
"{error}; failed to roll back provider chat selections: {rollback}"
)));
}
return Err(internal(error));
}
};
if catalog_changed {
state.provider_epoch.store(target_epoch, Ordering::Release);
}
for (session_id, host) in migrations {
host.cut_over_provider(&selection).await?;
if !host.is_alive() {
state.sessions.remove(&session_id);
return Err(internal("chat stopped during provider replacement"));
}
}
let payload = gateway_ready(&state).await?;
let frame = ServerFrame::new(ServerMessage::Ready {
payload: payload.clone(),
});
let _ = self.events.send(frame);
Ok(payload)
}
pub(crate) async fn remove_provider(
&self,
instance: String,
) -> std::result::Result<ReadyPayload, Rejection> {
let mut state = self.state.lock().await;
let mutation_gate = Arc::clone(&state.session_mutations);
let _mutation = mutation_gate.write_owned().await;
state
.config
.lock()
.map_err(|_| internal("gateway configuration lock is poisoned"))?
.removing_provider(&instance)
.map_err(invalid_config)?;
let target_epoch = state
.provider_epoch
.load(Ordering::Acquire)
.checked_add(1)
.ok_or_else(|| internal("provider catalog epoch overflow"))?;
let residents = provider_cutover_residents(&mut state).await?;
if residents.iter().any(|resident| !resident.status.idle) {
return Err(Rejection {
code: "agent_busy",
message: "finish or interrupt active turns before removing a gateway provider"
.into(),
fatal: false,
});
}
commit_provider_removal(&state, &instance).map_err(internal)?;
state.provider_epoch.store(target_epoch, Ordering::Release);
let mut reload_failures = Vec::new();
for resident in residents {
if let Err(error) = resident.host.reload_provider_catalog().await {
if !resident.host.stop_if_idle().await {
return Err(internal(
"chat became busy after provider removal was committed",
));
}
state.sessions.remove(&resident.session_id);
reload_failures.push(format!("{}: {}", resident.session_id, error.message));
}
}
let payload = gateway_ready(&state).await?;
let _ = self.events.send(ServerFrame::new(ServerMessage::Ready {
payload: payload.clone(),
}));
if !reload_failures.is_empty() {
let _ = self.events.send(ServerFrame::new(ServerMessage::Error {
code: "provider_reload".into(),
message: format!(
"provider removed; reopen chats that could not reload: {}",
reload_failures.join(", ")
),
fatal: false,
}));
}
Ok(payload)
}
}
fn provider_registration(
current: &GatewayConfig,
selection: &ProviderConfig,
label: &str,
tint: ProviderTint,
model_ids: &[String],
reasoning_efforts: &[String],
replace_existing_selections: bool,
) -> crate::Result<GatewayConfig> {
let registered = current.registering_provider(
selection.clone(),
label.to_owned(),
tint,
model_ids.to_vec(),
reasoning_efforts.to_vec(),
)?;
if replace_existing_selections {
registered.replacing_provider_default(selection)
} else {
Ok(registered)
}
}
fn commit_provider_registration(
state: &super::GatewayState,
selection: &ProviderConfig,
label: &str,
tint: ProviderTint,
model_ids: &[String],
reasoning_efforts: &[String],
replace_existing_selections: bool,
) -> crate::Result<bool> {
let mut current = state
.config
.lock()
.map_err(|_| Error::Config("gateway configuration lock is poisoned".into()))?;
let next = provider_registration(
¤t,
selection,
label,
tint,
model_ids,
reasoning_efforts,
replace_existing_selections,
)?;
let catalog_changed = current.configured_providers != next.configured_providers;
state.store.save(&next)?;
*current = next;
Ok(catalog_changed)
}
fn commit_provider_removal(state: &super::GatewayState, instance: &str) -> crate::Result<()> {
let mut current = state
.config
.lock()
.map_err(|_| Error::Config("gateway configuration lock is poisoned".into()))?;
let next = current.removing_provider(instance)?;
state.store.save(&next)?;
if let Err(error) = state.credentials.remove(instance) {
if let Err(rollback) = state.store.save(¤t) {
return Err(Error::Config(format!(
"{error}; failed to roll back provider configuration: {rollback}"
)));
}
return Err(error);
}
*current = next;
Ok(())
}
struct ProviderCheckpointReplacement {
session_id: String,
sequence: u64,
original: ChatSpec,
updated: ChatSpec,
}
struct ProviderCutoverResident {
session_id: String,
host: super::HostHandle,
status: super::ProviderCutoverStatus,
}
async fn provider_cutover_residents(
state: &mut super::GatewayState,
) -> std::result::Result<Vec<ProviderCutoverResident>, Rejection> {
let sessions = state
.sessions
.iter()
.map(|(id, host)| (id.clone(), host.clone()))
.collect::<Vec<_>>();
let mut residents = Vec::new();
let mut stopped = Vec::new();
for (id, host) in sessions {
if !host.is_alive() {
stopped.push(id);
continue;
}
match host.provider_cutover_status().await {
Ok(status) => residents.push(ProviderCutoverResident {
session_id: id,
host,
status,
}),
Err(rejection) if rejection.code == "gateway_stopped" => stopped.push(id),
Err(rejection) => return Err(rejection),
}
}
for id in stopped {
state.sessions.remove(&id);
}
Ok(residents)
}
async fn provider_checkpoint_replacements(
state: &super::GatewayState,
selection: &ProviderConfig,
gateway: &GatewayConfig,
excluded: &HashSet<String>,
) -> crate::Result<Vec<ProviderCheckpointReplacement>> {
let sessions = super::gateway_session_summaries(&state.checkpoints).await?;
let mut replacements = Vec::new();
for session in sessions {
if excluded.contains(&session.session_id) {
continue;
}
let Some(checkpoint) = state.checkpoints.load(&session.session_id).await? else {
continue;
};
let Some(original) = ChatSpec::from_metadata_if_present(
&checkpoint.metadata,
state.store.state_dir(),
gateway.tls.as_ref(),
)?
else {
continue;
};
let Some(updated) = original.replacing_provider_selection(
selection,
gateway,
state.store.state_dir(),
gateway.tls.as_ref(),
)?
else {
continue;
};
replacements.push(ProviderCheckpointReplacement {
session_id: session.session_id,
sequence: checkpoint.sequence,
original,
updated,
});
}
Ok(replacements)
}
async fn save_provider_checkpoint_replacements(
checkpoints: &Arc<dyn CheckpointStore>,
replacements: &[ProviderCheckpointReplacement],
) -> crate::Result<()> {
for (index, replacement) in replacements.iter().enumerate() {
let result = async {
let mut checkpoint = checkpoints
.load(&replacement.session_id)
.await?
.ok_or_else(|| {
Error::Config("chat disappeared during provider replacement".into())
})?;
if checkpoint.sequence != replacement.sequence {
return Err(Error::Config(
"chat changed during provider replacement".into(),
));
}
checkpoint.sequence = checkpoint
.sequence
.checked_add(1)
.ok_or_else(|| Error::Config("checkpoint sequence overflow".into()))?;
checkpoint.metadata.extend(replacement.updated.metadata()?);
checkpoints.save(&checkpoint, &[], None).await?;
Ok(())
}
.await;
if let Err(error) = result {
if let Err(rollback) =
rollback_provider_checkpoints(checkpoints, &replacements[..index]).await
{
return Err(Error::Config(format!(
"{error}; failed to roll back provider chat selections: {rollback}"
)));
}
return Err(error);
}
}
Ok(())
}
async fn rollback_provider_checkpoints(
checkpoints: &Arc<dyn CheckpointStore>,
replacements: &[ProviderCheckpointReplacement],
) -> crate::Result<()> {
for replacement in replacements.iter().rev() {
let mut checkpoint = checkpoints
.load(&replacement.session_id)
.await?
.ok_or_else(|| Error::Config("chat disappeared during provider rollback".into()))?;
let replaced_sequence = replacement
.sequence
.checked_add(1)
.ok_or_else(|| Error::Config("checkpoint sequence overflow".into()))?;
if checkpoint.sequence != replaced_sequence {
return Err(Error::Config(
"chat changed during provider rollback".into(),
));
}
checkpoint.sequence = checkpoint
.sequence
.checked_add(1)
.ok_or_else(|| Error::Config("checkpoint sequence overflow".into()))?;
checkpoint.metadata.extend(replacement.original.metadata()?);
checkpoints.save(&checkpoint, &[], None).await?;
}
Ok(())
}
fn ensure_provider_login_available(
active_login: Option<&str>,
) -> std::result::Result<(), Rejection> {
if active_login.is_some() {
return Err(Rejection {
code: "provider_login_in_progress",
message: "finish the active provider login before starting another".into(),
fatal: false,
});
}
Ok(())
}
fn reserve_provider_login(
active_login: &StdMutex<Option<String>>,
login_id: &str,
) -> std::result::Result<(), Rejection> {
let mut active_login = active_login
.lock()
.map_err(|_| internal("provider login lock is poisoned"))?;
ensure_provider_login_available(active_login.as_deref())?;
*active_login = Some(login_id.into());
Ok(())
}
fn release_provider_login(
active_login: &StdMutex<Option<String>>,
login_id: &str,
) -> std::result::Result<bool, Rejection> {
let mut active_login = active_login
.lock()
.map_err(|_| internal("provider login lock is poisoned"))?;
if active_login.as_deref() != Some(login_id) {
return Ok(false);
}
*active_login = None;
Ok(true)
}
#[cfg(test)]
#[path = "tests/providers.rs"]
mod tests;