llama-stack/llama_stack/distribution/resolver.py
Ashwin Bharambe 6609d4ada4
feat: allow conditionally enabling providers in run.yaml (#1321)
# What does this PR do?

We want to bundle a bunch of (typically remote) providers in a distro
template and be able to configure them "on the fly" via environment
variables. So far, we have been able to do this with simple env var
replacements. However, sometimes you want to only conditionally enable
providers (because the relevant remote services may not be alive, or
relevant.) This was not possible until now.

To aid this, we add a simple (bash-like) env var replacement
enhancement: `${env.FOO+bar}` evaluates to `bar` if the variable is SET
and evaluates to empty string if it is not. On top of that, we update
our main resolver to ignore any provider whose ID is null.

This allows using the distro like this:

```bash
llama stack run dev --env CHROMADB_URL=http://localhost:6001 --env ENABLE_CHROMADB=1
```

when only Chroma is UP. This disables the other `pgvector` provider in
the run configuration.


## Test Plan

Hard code `chromadb` as the vector io provider inside
`test_vector_io.py` and run:

```bash
LLAMA_STACK_BASE_URL=http://localhost:8321 pytest -s -v tests/client-sdk/vector_io/ --embedding-model all-MiniLM-L6-v2
```
2025-03-01 11:19:14 -08:00

394 lines
14 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import importlib
import inspect
import logging
from typing import Any, Dict, List, Set
from llama_stack.apis.agents import Agents
from llama_stack.apis.benchmarks import Benchmarks
from llama_stack.apis.datasetio import DatasetIO
from llama_stack.apis.datasets import Datasets
from llama_stack.apis.eval import Eval
from llama_stack.apis.inference import Inference
from llama_stack.apis.inspect import Inspect
from llama_stack.apis.models import Models
from llama_stack.apis.post_training import PostTraining
from llama_stack.apis.safety import Safety
from llama_stack.apis.scoring import Scoring
from llama_stack.apis.scoring_functions import ScoringFunctions
from llama_stack.apis.shields import Shields
from llama_stack.apis.telemetry import Telemetry
from llama_stack.apis.tools import ToolGroups, ToolRuntime
from llama_stack.apis.vector_dbs import VectorDBs
from llama_stack.apis.vector_io import VectorIO
from llama_stack.distribution.client import get_client_impl
from llama_stack.distribution.datatypes import (
AutoRoutedProviderSpec,
Provider,
RoutingTableProviderSpec,
StackRunConfig,
)
from llama_stack.distribution.distribution import builtin_automatically_routed_apis
from llama_stack.distribution.store import DistributionRegistry
from llama_stack.distribution.utils.dynamic import instantiate_class_type
from llama_stack.providers.datatypes import (
Api,
BenchmarksProtocolPrivate,
DatasetsProtocolPrivate,
InlineProviderSpec,
ModelsProtocolPrivate,
ProviderSpec,
RemoteProviderConfig,
RemoteProviderSpec,
ScoringFunctionsProtocolPrivate,
ShieldsProtocolPrivate,
ToolsProtocolPrivate,
VectorDBsProtocolPrivate,
)
log = logging.getLogger(__name__)
class InvalidProviderError(Exception):
pass
def api_protocol_map() -> Dict[Api, Any]:
return {
Api.agents: Agents,
Api.inference: Inference,
Api.inspect: Inspect,
Api.vector_io: VectorIO,
Api.vector_dbs: VectorDBs,
Api.models: Models,
Api.safety: Safety,
Api.shields: Shields,
Api.telemetry: Telemetry,
Api.datasetio: DatasetIO,
Api.datasets: Datasets,
Api.scoring: Scoring,
Api.scoring_functions: ScoringFunctions,
Api.eval: Eval,
Api.benchmarks: Benchmarks,
Api.post_training: PostTraining,
Api.tool_groups: ToolGroups,
Api.tool_runtime: ToolRuntime,
}
def additional_protocols_map() -> Dict[Api, Any]:
return {
Api.inference: (ModelsProtocolPrivate, Models, Api.models),
Api.tool_groups: (ToolsProtocolPrivate, ToolGroups, Api.tool_groups),
Api.vector_io: (VectorDBsProtocolPrivate, VectorDBs, Api.vector_dbs),
Api.safety: (ShieldsProtocolPrivate, Shields, Api.shields),
Api.datasetio: (DatasetsProtocolPrivate, Datasets, Api.datasets),
Api.scoring: (
ScoringFunctionsProtocolPrivate,
ScoringFunctions,
Api.scoring_functions,
),
Api.eval: (BenchmarksProtocolPrivate, Benchmarks, Api.benchmarks),
}
# TODO: make all this naming far less atrocious. Provider. ProviderSpec. ProviderWithSpec. WTF!
class ProviderWithSpec(Provider):
spec: ProviderSpec
ProviderRegistry = Dict[Api, Dict[str, ProviderSpec]]
# TODO: this code is not very straightforward to follow and needs one more round of refactoring
async def resolve_impls(
run_config: StackRunConfig,
provider_registry: ProviderRegistry,
dist_registry: DistributionRegistry,
) -> Dict[Api, Any]:
"""
Does two things:
- flatmaps, sorts and resolves the providers in dependency order
- for each API, produces either a (local, passthrough or router) implementation
"""
routing_table_apis = {x.routing_table_api for x in builtin_automatically_routed_apis()}
router_apis = {x.router_api for x in builtin_automatically_routed_apis()}
providers_with_specs = {}
for api_str, providers in run_config.providers.items():
api = Api(api_str)
if api in routing_table_apis:
raise ValueError(f"Provider for `{api_str}` is automatically provided and cannot be overridden")
specs = {}
for provider in providers:
if not provider.provider_id or provider.provider_id == "__disabled__":
log.warning(f"Provider `{provider.provider_type}` for API `{api}` is disabled")
continue
if provider.provider_type not in provider_registry[api]:
raise ValueError(f"Provider `{provider.provider_type}` is not available for API `{api}`")
p = provider_registry[api][provider.provider_type]
if p.deprecation_error:
log.error(p.deprecation_error, "red", attrs=["bold"])
raise InvalidProviderError(p.deprecation_error)
elif p.deprecation_warning:
log.warning(
f"Provider `{provider.provider_type}` for API `{api}` is deprecated and will be removed in a future release: {p.deprecation_warning}",
)
p.deps__ = [a.value for a in p.api_dependencies] + [a.value for a in p.optional_api_dependencies]
spec = ProviderWithSpec(
spec=p,
**(provider.model_dump()),
)
specs[provider.provider_id] = spec
key = api_str if api not in router_apis else f"inner-{api_str}"
providers_with_specs[key] = specs
apis_to_serve = run_config.apis or set(
list(providers_with_specs.keys()) + [x.value for x in routing_table_apis] + [x.value for x in router_apis]
)
for info in builtin_automatically_routed_apis():
if info.router_api.value not in apis_to_serve:
continue
providers_with_specs[info.routing_table_api.value] = {
"__builtin__": ProviderWithSpec(
provider_id="__routing_table__",
provider_type="__routing_table__",
config={},
spec=RoutingTableProviderSpec(
api=info.routing_table_api,
router_api=info.router_api,
module="llama_stack.distribution.routers",
api_dependencies=[],
deps__=([f"inner-{info.router_api.value}"]),
),
)
}
providers_with_specs[info.router_api.value] = {
"__builtin__": ProviderWithSpec(
provider_id="__autorouted__",
provider_type="__autorouted__",
config={},
spec=AutoRoutedProviderSpec(
api=info.router_api,
module="llama_stack.distribution.routers",
routing_table_api=info.routing_table_api,
api_dependencies=[info.routing_table_api],
deps__=([info.routing_table_api.value]),
),
)
}
sorted_providers = topological_sort({k: v.values() for k, v in providers_with_specs.items()})
apis = [x[1].spec.api for x in sorted_providers]
sorted_providers.append(
(
"inspect",
ProviderWithSpec(
provider_id="__builtin__",
provider_type="__builtin__",
config={
"run_config": run_config.dict(),
},
spec=InlineProviderSpec(
api=Api.inspect,
provider_type="__builtin__",
config_class="llama_stack.distribution.inspect.DistributionInspectConfig",
module="llama_stack.distribution.inspect",
api_dependencies=apis,
deps__=([x.value for x in apis]),
),
),
)
)
log.info(f"Resolved {len(sorted_providers)} providers")
for api_str, provider in sorted_providers:
log.info(f" {api_str} => {provider.provider_id}")
log.info("")
impls = {}
inner_impls_by_provider_id = {f"inner-{x.value}": {} for x in router_apis}
for api_str, provider in sorted_providers:
deps = {a: impls[a] for a in provider.spec.api_dependencies}
for a in provider.spec.optional_api_dependencies:
if a in impls:
deps[a] = impls[a]
inner_impls = {}
if isinstance(provider.spec, RoutingTableProviderSpec):
inner_impls = inner_impls_by_provider_id[f"inner-{provider.spec.router_api.value}"]
impl = await instantiate_provider(
provider,
deps,
inner_impls,
dist_registry,
)
# TODO: ugh slightly redesign this shady looking code
if "inner-" in api_str:
inner_impls_by_provider_id[api_str][provider.provider_id] = impl
else:
api = Api(api_str)
impls[api] = impl
return impls
def topological_sort(
providers_with_specs: Dict[str, List[ProviderWithSpec]],
) -> List[ProviderWithSpec]:
def dfs(kv, visited: Set[str], stack: List[str]):
api_str, providers = kv
visited.add(api_str)
deps = []
for provider in providers:
for dep in provider.spec.deps__:
deps.append(dep)
for dep in deps:
if dep not in visited and dep in providers_with_specs:
dfs((dep, providers_with_specs[dep]), visited, stack)
stack.append(api_str)
visited = set()
stack = []
for api_str, providers in providers_with_specs.items():
if api_str not in visited:
dfs((api_str, providers), visited, stack)
flattened = []
for api_str in stack:
for provider in providers_with_specs[api_str]:
flattened.append((api_str, provider))
return flattened
# returns a class implementing the protocol corresponding to the Api
async def instantiate_provider(
provider: ProviderWithSpec,
deps: Dict[str, Any],
inner_impls: Dict[str, Any],
dist_registry: DistributionRegistry,
):
protocols = api_protocol_map()
additional_protocols = additional_protocols_map()
provider_spec = provider.spec
module = importlib.import_module(provider_spec.module)
args = []
if isinstance(provider_spec, RemoteProviderSpec):
config_type = instantiate_class_type(provider_spec.config_class)
config = config_type(**provider.config)
method = "get_adapter_impl"
args = [config, deps]
elif isinstance(provider_spec, AutoRoutedProviderSpec):
method = "get_auto_router_impl"
config = None
args = [provider_spec.api, deps[provider_spec.routing_table_api], deps]
elif isinstance(provider_spec, RoutingTableProviderSpec):
method = "get_routing_table_impl"
config = None
args = [provider_spec.api, inner_impls, deps, dist_registry]
else:
method = "get_provider_impl"
config_type = instantiate_class_type(provider_spec.config_class)
config = config_type(**provider.config)
args = [config, deps]
fn = getattr(module, method)
impl = await fn(*args)
impl.__provider_id__ = provider.provider_id
impl.__provider_spec__ = provider_spec
impl.__provider_config__ = config
# TODO: check compliance for special tool groups
# the impl should be for Api.tool_runtime, the name should be the special tool group, the protocol should be the special tool group protocol
check_protocol_compliance(impl, protocols[provider_spec.api])
if not isinstance(provider_spec, AutoRoutedProviderSpec) and provider_spec.api in additional_protocols:
additional_api, _, _ = additional_protocols[provider_spec.api]
check_protocol_compliance(impl, additional_api)
return impl
def check_protocol_compliance(obj: Any, protocol: Any) -> None:
missing_methods = []
mro = type(obj).__mro__
for name, value in inspect.getmembers(protocol):
if inspect.isfunction(value) and hasattr(value, "__webmethod__"):
if not hasattr(obj, name):
missing_methods.append((name, "missing"))
elif not callable(getattr(obj, name)):
missing_methods.append((name, "not_callable"))
else:
# Check if the method signatures are compatible
obj_method = getattr(obj, name)
proto_sig = inspect.signature(value)
obj_sig = inspect.signature(obj_method)
proto_params = set(proto_sig.parameters)
proto_params.discard("self")
obj_params = set(obj_sig.parameters)
obj_params.discard("self")
if not (proto_params <= obj_params):
log.error(f"Method {name} incompatible proto: {proto_params} vs. obj: {obj_params}")
missing_methods.append((name, "signature_mismatch"))
else:
# Check if the method is actually implemented in the class
method_owner = next((cls for cls in mro if name in cls.__dict__), None)
if method_owner is None or method_owner.__name__ == protocol.__name__:
missing_methods.append((name, "not_actually_implemented"))
if missing_methods:
raise ValueError(
f"Provider `{obj.__provider_id__} ({obj.__provider_spec__.api})` does not implement the following methods:\n{missing_methods}"
)
async def resolve_remote_stack_impls(
config: RemoteProviderConfig,
apis: List[str],
) -> Dict[Api, Any]:
protocols = api_protocol_map()
additional_protocols = additional_protocols_map()
impls = {}
for api_str in apis:
api = Api(api_str)
impls[api] = await get_client_impl(
protocols[api],
config,
{},
)
if api in additional_protocols:
_, additional_protocol, additional_api = additional_protocols[api]
impls[additional_api] = await get_client_impl(
additional_protocol,
config,
{},
)
return impls