10 Commits

Author	SHA1	Message	Date
Ettore Di Giacinto	2f6e0481f7	backend(audio-cpp): bound the lane a live stream can hold ... AudioTranscriptionLive holds the model's inference lane for the whole stream, which is correct (the streaming session is stateful and a concurrent run would interleave two callers' audio) and newly dangerous. Every other RPC holds the lane across compute, or across a write to a slow reader, and both of those terminate on their own. A live stream instead blocks in a client-driven read, and a peer that goes silent WITHOUT closing the stream never terminates anything: the lane stays taken and every other request against that model queues behind a client that stopped speaking. live_watchdog is a one-shot idle timer that ends the stream when no frame has arrived inside a window. It is standard library only, so it is unit tested without an engine. gRPC's synchronous Read has no timeout and cannot be given one, so the only way to unblock it is ServerContext::TryCancel, which decides the wire status itself: the client sees CANCELLED rather than the DEADLINE_EXCEEDED the handler returns, the reason is logged, and the lane coming back is the point. When it fires the read loop throws rather than reporting end-of-input, so the driver does not go on to finalize a decode nobody is waiting for. It is armed only after the lane is taken and disarmed as soon as the read side closes, and both ends matter. Arming earlier would cover acquire(), which legitimately blocks while another live stream runs, so a queued caller would be cancelled for waiting its turn. Disarming later would cover our own decode, where a window overrun is not a peer going quiet and cancelling would throw away the transcript the client is waiting for. The window is the new live_idle_timeout_ms option, 30 s by default, 0 meaning no limit. core/http/endpoints/openai/realtime.go drives a 300 ms ticker and feeds every tick that produced new audio while a turn is open, so 30 s of silence is a hundred ticks that delivered nothing. It is also longer than any pause a speaker takes mid-utterance, which is the case that must never be cut off, and backend.proto lets one stream span many utterances, so a client that pauses longer between them raises the option rather than discovering it. Two smaller corrections in the same handler: - check_can_serve now runs BEFORE the sample rate check. pkg/grpc/grpcerrors/errors.go degrades to the file path on UNIMPLEMENTED and on nothing else, so a live-incapable model asked at a wrong rate was answering INVALID_ARGUMENT and costing the caller its fallback. - a negative sample rate is refused instead of silently becoming 16000. Zero still means 16000, which is what the proto documents; -1 is malformed rather than absent and gets the same refusal every other bad rate gets. And one thing recorded rather than changed, at the handler: "live" here means incremental INPUT, not low latency, and with the pinned families it does not yet mean incremental OUTPUT either. nemotron_asr's process_audio_chunk only appends to its buffer, so its whole decode and every delta happen inside finalize(), after the client closes its send side. The policy-window buffering is inert for that family and matters only for vibevoice_asr and higgs_audio_stt. Verified on the wire with live_idle_timeout_ms:3000. A silent client acked at 371 ms and was cancelled at 3.371 s; a second live stream opened one second later received its ack 2.37 s in, i.e. at the instant the first was cancelled, and then transcribed successfully on the same cached session. Without the watchdog it would still be waiting. Re-ran the live transcription (ready first, 59 incremental deltas, concat equal to the final text, word timestamps in nanoseconds, eou and eob false), the citrinet refusal at both a right and a wrong rate (UNIMPLEMENTED either way now), and Task 12's AudioTranscriptionStream on nemotron_asr, which is unchanged. Mutation testing the watchdog found a weakness in its own test: the destructor test slept past the window inside the watched scope, so a destructor that DETACHED the thread instead of joining it passed unnoticed. The test now uses a window longer than the scope, which kills that mutant, and says why. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-27 00:58:46 +00:00
Ettore Di Giacinto	8778600295	backend(audio-cpp): serve the AudioTranscriptionLive RPC ... The one bidirectional stream this backend serves. The client sends a TranscriptLiveConfig, then TranscriptLiveAudio frames; the server acknowledges with ready, emits deltas as the audio arrives, and sends final_result once the read side closes. There is no offline fallback: live transcription has to consume audio incrementally, so a family with no streaming ASR is refused rather than served a batch run, which is what this RPC's Streaming-only mode_candidates list already says. The driver is a new sibling of run_streaming_audio, run_streaming_live, because the audio does not exist yet: instead of slicing a buffer it pulls frames from the caller until the read side closes. It installs the same ScopedStreamSink in the same order, which is not optional, since nemotron_asr returns a bare event from process_audio_chunk and reports every partial through the sink from inside finalize(). It buffers the wire's frames up to the family's own preferred window rather than feeding whatever size the client's audio callback produced, and it does not call finish_stream at all when no audio arrived, because nemotron_asr throws "finalize requires streamed audio" and an empty transcript is the truthful answer to transcribing nothing. Three things the handler had to get right and one it cannot: - The audio contract. A live request carries no samples, but nemotron_asr's streaming prepare() throws without an audio contract, and build_preparation_request derives it from TaskRequest::audio_input, so that field is an EMPTY buffer holding only the rate and the channel count. - 16 kHz or a refusal. The families express their spans in their own 16 kHz feature domain whatever the input was, and live frames cannot be resampled on the way in the way a file can, so an 8 kHz session would return timestamps 2x off with a 200. core/backend hardcodes 16000 anyway. - A mid-stream Config is refused. backend.proto calls it a decoder reset, but deltas already on the wire cannot be retracted, so a reset would leave the final text contradicting the transcript the client assembled. Ignoring the message would hand a client that believes it reset the decoder a transcript that silently continues the audio it thought it discarded. - The stale-route identity check cannot run here: TranscriptLiveRequest carries no ModelIdentity in either arm of its oneof, so snapshot_for does not instantiate for it. snapshot_unchecked's comment now names that as a second legitimate class of caller and says the fix is a proto change. eou and eob stay false. They exist for cache-aware models that emit end-of-utterance and end-of-backchannel tokens; audio.cpp's StreamEvent has no equivalent signal, and a client uses eou to decide the speaker yielded the turn, so a guess inferred from silence cuts people off mid-sentence. The lane is held for the whole stream, which is as long as the user keeps talking: the streaming session is stateful and cached, so a concurrent run would interleave two callers' audio and corrupt both transcripts. Verified against nemotron_asr over a real connection with a 14 s WAV in 512-sample frames: ready first, 59 incremental deltas with no repeated prefix, concat(deltas) equal to final_result.text, word timestamps in nanoseconds, eou and eob false. citrinet_asr answers UNIMPLEMENTED naming the family and listing asr/offline. A config followed by a close returns an empty final_result rather than hanging, and a first message that is not a config is INVALID_ARGUMENT. Two concurrent streams both return the complete transcript. Two cleanups on lines Task 12 touched, folded in. The DtypeAllowList terminator is now asserted at compile time: the reported out-of-bounds read did not exist, the single entry does terminate, but the loops have no other bound and any edit that widened an entry would walk off the end. And the dtype guard now short-circuits on "is there a table entry" through a new predicate rather than on the emptiness of the description string, which would have skipped the check on an entry with an empty allow list, i.e. on precisely the entry that refuses every dtype. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-27 00:27:08 +00:00
Ettore Di Giacinto	41b4e72041	backend(audio-cpp): serve the TTSStream and AudioTranscriptionStream RPCs ... TTSStream leads with a streaming WAV header carrying 0xFFFFFFFF sizes, matching the convention backend/go/vibevoice-cpp established, so an HTTP client can start playback before the full PCM exists. Its chunks are read from StreamEvent::named_audio_outputs and not audio_output: supertonic, omnivoice and voxcpm2 all put their streamed audio there and leave audio_output empty until the very end, so reading the obvious field yields a stream with no audio in it. The finish_stream result is the family's own merged whole rather than a tail, so it is emitted only when nothing was streamed. Streaming transcription sends incremental deltas and degrades to a single delta plus the final result on families that offer no streaming ASR, which is the same message sequence with fewer deltas. The four streaming ASR families disagree on what partial_text means: nemotron_asr, vibevoice_asr and higgs_audio_stt report incremental fragments while voxtral_realtime reports the whole hypothesis and reports it twice, so the reconciliation lives in one tested unit rather than in the handler. nemotron_asr reports only through the stream event sink, and only from inside finalize, so the audio driver installs one and clears it again before returning: the session is cached and a sink left holding the caller's frame is a use after free waiting for the next stream. begin_stream is now the only implementation of the streaming state obligation, prepare then start_stream. Streaming sessions are cached, and what clears the previous stream is start_stream's reset; a family override that dropped it would break every call site with no compile error, so there is one call site. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-26 22:35:43 +00:00
Ettore Di Giacinto	2b1d3c9408	backend(audio-cpp): refuse an impossible stem early, and stop blaming the caller for a failed write ... Four fixes from the first review of the AudioTransform RPC. check_can_serve now returns the resolved route, so params[stem] on a route that is not source separation is refused from the route instead of after a full inference: 11 ms rather than the 4.5 s a miocodec conversion costs, and far worse on seed_vc or vevo2. The post-run refusal stays as the backstop for a separation-routed family that returns no stems anyway. The typo'd-stem-name case still needs the run, since no framework header publishes the stem names before one. Stem names carrying control bytes are refused. GGUF strings are length prefixed and demucs reads its sources from JSON, so an embedded NUL survives to here: two names differing only after the NUL are distinct std::strings, so the duplicate check passes them, and then path::c_str() truncates both and they open the same file. That is exactly the silent overwrite the duplicate check exists to prevent, with the .wav lost as well. A failed write is now INTERNAL rather than INVALID_ARGUMENT. The destination is LocalAI's own generated-content directory, not anything the caller named, so a full disk or a permission fault there is a server fault and is worth retrying, which is the opposite of what INVALID_ARGUMENT tells a client. An empty output path stays INVALID_ARGUMENT. Two comment corrections and one clarification: the separators' required rate is their checkpoint's declared samplerate rather than a hardcoded 44100, seed_vc resamples with soxr and falls back to sinc-hann, and the "no files left behind" guarantee covers a refused request, not a write that fails partway through the loop. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-26 18:15:13 +00:00
Ettore Di Giacinto	6ee95ab01b	backend(audio-cpp): serve the AudioTranscription RPC ... Adds result_map, the engine-to-proto boundary, and wires the offline transcription RPC. The handler branches on the ROUTED task: for Asr the request's prompt is whisper-style decoding context and becomes a request option, for Alignment the same field IS the transcript to align and becomes the text input. Routing has already decided which. The result text is TaskResult.text_output verbatim and is never derived from the segments. audio.cpp carries transcript text in text_output and nowhere else, so deriving it returns an empty transcript for every producer that reports segments without word timing. transcript_assembly already enforces that; this commit's job is not to undo it at the proto boundary, and result_map_ctest pins it there. read_audio_file now takes the sample rate the caller needs. Both file-fed speech handlers ask for 16 kHz mono, for two reasons: silero_vad and sortformer_diar refuse anything else outright, which turned an ordinary 44.1 kHz upload into INTERNAL, and nemotron_asr emits word timestamps in its own 16 kHz feature domain whatever the input was, so only a 16 kHz buffer makes the emitted nanoseconds right. Zero keeps the file's native rate and channels, which is what source separation will need. LoadedModel::check_can_serve answers a capability refusal before the lane is taken and before the input file is read. Routing is a pure read of the immutable capabilities, so a model that cannot serve an RPC no longer waits out somebody else's run to say so. VAD and Diarize use it too. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-26 16:11:45 +00:00
Ettore Di Giacinto	51dec81e9a	backend(audio-cpp): make the lane and identity guards structural ... Two hardenings ahead of the eleven handlers still to be written, both of which get harder to retrofit later. The lane proof-of-holding parameter was a const reference, which binds to a temporary, so session_for(rpc, shape, model->acquire(0)) compiled. Each such temporary dies at the end of its own full-expression, releasing the lane between two calls that must share one: precisely the split the parameter exists to prevent, and the form a future author is most likely to reach for because it reads as tidy. A non-const reference requires an lvalue, so the temporary form now fails to compile while the named-local handlers build unchanged. The header comment no longer implies the check is total either: it proves a lane was taken, not that it is this model's lane. The identity check was two lines each handler had to remember, with nothing failing if a new one forgot them and no C++ equivalent of model_identity_modalities_test.go to notice. snapshot() becomes snapshot_unchecked(), whose only legitimate caller is Status, since HealthMessage carries no ModelIdentity. Handlers go through snapshot_for(), which takes the counted reference, refuses when nothing is loaded, and runs the identity check before anything can route. Every handler already has to call something to obtain the model, so the guarded call is now the shortest path and skipping it means deliberately typing snapshot_unchecked. A convention that has to be remembered can rot; this cannot. Verified: the temporary-argument and inverted-order forms each fail to compile with the expected diagnostic, the real handlers build, and bypassing the guard in Diarize alone turns the identity test red on that RPC while VAD stays green. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-26 15:24:22 +00:00
Ettore Di Giacinto	676e7bb764	backend(audio-cpp): enforce ModelIdentity on VAD and Diarize ... audio-cpp was the only C++ backend without the model-identity guard, and no later task in the plan added it. pkg/grpc/server.go enforces checkModelIdentity on exactly these two RPCs, for the reason #10952 records: in distributed mode a worker can recycle a stopped backend's gRPC port for another model's backend, and the controller's liveness-only probe cannot tell a stale cached route from a live one. Without this guard a stale route gets a different model's VAD or diarization answer back with a 200. The loaded identity lives on LoadedModel rather than in a separate global, which is where this differs from llama-cpp. A handler holding the model through snapshot() then necessarily judges against the identity that model was loaded with, and a concurrent reload cannot swap one without the other. The refusal is NOT_FOUND carrying the verbatim grpcerrors.ModelMismatchSentinel substring. session_for and run_offline now take a const LaneEntry & proof-of-holding parameter. The rule that both must run under the inference lane was prose, which is exactly how the plan came to specify the inverted order; it is now a compile error. Restoring the inverted order fails to build rather than racing on an unsynchronised session map with a mutating prepare(). Diarize's speaker-hint comment claimed the dropped hints were "not a silent failure". From the caller's side that is what they are, and backend.proto documents num_speakers as forcing, so the comment now says plainly that the forwarding is dead for sortformer and that the family which lands must either honour num_speakers or refuse it. read_audio_file inspects the error_code from exists(), so an unsearchable parent directory no longer reports as a missing file. The VAD handler records the stimulus that actually works, since silero correctly ignores synthetic tones and the next task would otherwise rediscover that. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-26 15:05:22 +00:00
Ettore Di Giacinto	f08d5f8b3d	backend(audio-cpp): serve the VAD and Diarize RPCs ... Both emit float seconds, converted from the runtime's sample-index spans, and both take a counted reference to the loaded model through snapshot() and hold it for the whole call: a Free arriving mid-request drops only the global's reference, so whichever request finishes last destroys the model instead of one of them running on freed weights. An AddressSanitizer build reproduces exactly that heap-use-after-free inside ggml_vec_dot_f32 when the handler keeps a raw pointer instead, which is why the shape is what it is. The inference lane is taken before session_for, not after. session_for reads and writes an unsynchronised session cache and the offline run calls prepare(), which mutates the session, so both belong inside the lane. Diarize routes before it reads the input file, so a family that cannot diarize at all says so rather than complaining about the audio first. Its per-segment text stays empty because audio.cpp's SpeakerTurn carries a span and a speaker label only, and nested or overlapping turns are passed through untouched: a sortformer turn inside another speaker's turn is correct output for overlapped speech, and LocalAI is overlap-tolerant downstream. Duration counts frames rather than floats, so a stereo input does not report twice its length. Verified end to end against upstream's bundled silero_vad, which needs no download, using the bundled 16 kHz speech asset: a synthetic tone returns nothing, correctly, because silero detects speech and a sine is not speech. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-26 14:41:54 +00:00
Ettore Di Giacinto	fac26a23df	backend(audio-cpp): correct the status, lifetime and state contracts of LoadedModel ... An environment fault during session creation was reported as UNIMPLEMENTED. A missing libggml-cpu-*.so surfaced to the client as 'family silero_vad advertises vad/offline but refused to create the session: Failed to initialize CPU backend', which tells LocalAI the model cannot do this and must never be retried, and sends an operator hunting a capability bug instead of a packaging one. A throw from create_task_session is now a plain runtime_error, so it maps to INTERNAL. Only a null return, where the family genuinely declined, stays a CapabilityError. The model.'s task: option was parsed and then dropped: it lived in a local that died at the end of LoadModel and had no route to RequestShape::pinned_task. LoadedModel now keeps it and exposes pinned_task(). The global model becomes a shared_ptr reached through snapshot(). An audio RPC runs for seconds and cannot hold g_model_mu for its duration, so under a unique_ptr a Free arriving mid-request would destroy the model underneath it. Handlers now take a counted reference and whichever finishes last does the teardown, outside the lock. session_for documents the streaming state contract rather than resetting the session itself. Resetting on a cache hit was tried first and is not possible: silero_vad throws 'session prepare() must be called before Silero VAD reset()', so it would turn an ordinary second fetch into a hard error. start_stream's base implementation is already a reset, so a caller that runs prepare then start_stream per stream gets a clean session; a probe against the bundled silero_vad confirms an identical replay when it does and a carried-over stream when it does not. Also: an unknown backend: name is rejected before the model loads rather than after; MainGPU is parsed instead of passed through std::atoi, which turned 'gpu1' into device 0 silently; and device carries a device_set flag, because 0 is both the default and a real device index, so MainGPU was overriding an explicit device:0 that the neighbouring threads: handling promises will win. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-26 14:01:34 +00:00
Ettore Di Giacinto	9b394c41f7	backend(audio-cpp): load models and cache sessions per task ... Loads one ILoadedVoiceModel and creates an IVoiceTaskSession lazily per (task, mode), so the same model serves both the unary and streaming RPCs. LoadModel derives the family from GGUF metadata or an explicit option and fails with INVALID_ARGUMENT otherwise, so a failed load is a gRPC error the backend probe can see. audiocpp_backend::Task mirrors engine::runtime::VoiceTaskKind positionally, and drift there is silent: every unit still compiles and every test still passes while the backend runs a different task. Two mechanisms pin it. The static_asserts in loaded_model.cpp catch an insertion or a reorder, and -Werror=switch on that one file turns an appended upstream enumerator into a build failure rather than a warning in a 600 file log. Assisted-by: Claude:claude-opus-5 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>	2026-07-26 13:34:14 +00:00