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
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client-sdk	fix: RAG with documents (#1337)	2025-02-28 16:51:00 -08:00
test_replace_env_vars.py	feat: allow conditionally enabling providers in run.yaml (#1321)	2025-03-01 11:19:14 -08:00