fix: allow default empty vars for conditionals (#2570)

# What does this PR do?

We were not using conditionals correctly, conditionals can only be used
when the env variable is set, so `${env.ENVIRONMENT:+}` would return
None is ENVIRONMENT is not set.

If you want to create a conditional value, you need to do
`${env.ENVIRONMENT:=}`, this will pick the value of ENVIRONMENT if set,
otherwise will return None.

Closes: https://github.com/meta-llama/llama-stack/issues/2564

Signed-off-by: Sébastien Han <seb@redhat.com>

llama_stack/templates/starter/run.yaml

@@ -16,17 +16,17 @@ providers:
   - provider_id: openai
     provider_type: remote::openai
     config:
-      api_key: ${env.OPENAI_API_KEY:+}
+      api_key: ${env.OPENAI_API_KEY:=}
   - provider_id: fireworks
     provider_type: remote::fireworks
     config:
       url: https://api.fireworks.ai/inference/v1
-      api_key: ${env.FIREWORKS_API_KEY:+}
+      api_key: ${env.FIREWORKS_API_KEY:=}
   - provider_id: together
     provider_type: remote::together
     config:
       url: https://api.together.xyz/v1
-      api_key: ${env.TOGETHER_API_KEY:+}
+      api_key: ${env.TOGETHER_API_KEY:=}
   - provider_id: ollama
     provider_type: remote::ollama
     config:
@@ -35,21 +35,21 @@ providers:
   - provider_id: anthropic
     provider_type: remote::anthropic
     config:
-      api_key: ${env.ANTHROPIC_API_KEY:+}
+      api_key: ${env.ANTHROPIC_API_KEY:=}
   - provider_id: gemini
     provider_type: remote::gemini
     config:
-      api_key: ${env.GEMINI_API_KEY:+}
+      api_key: ${env.GEMINI_API_KEY:=}
   - provider_id: groq
     provider_type: remote::groq
     config:
       url: https://api.groq.com
-      api_key: ${env.GROQ_API_KEY:+}
+      api_key: ${env.GROQ_API_KEY:=}
   - provider_id: sambanova
     provider_type: remote::sambanova
     config:
       url: https://api.sambanova.ai/v1
-      api_key: ${env.SAMBANOVA_API_KEY:+}
+      api_key: ${env.SAMBANOVA_API_KEY:=}
   - provider_id: vllm
     provider_type: remote::vllm
     config:
@@ -83,15 +83,15 @@ providers:
   - provider_id: ${env.ENABLE_CHROMADB:+chromadb}
     provider_type: remote::chromadb
     config:
-      url: ${env.CHROMADB_URL:+}
+      url: ${env.CHROMADB_URL:=}
   - provider_id: ${env.ENABLE_PGVECTOR:+pgvector}
     provider_type: remote::pgvector
     config:
       host: ${env.PGVECTOR_HOST:=localhost}
       port: ${env.PGVECTOR_PORT:=5432}
-      db: ${env.PGVECTOR_DB:+}
-      user: ${env.PGVECTOR_USER:+}
-      password: ${env.PGVECTOR_PASSWORD:+}
+      db: ${env.PGVECTOR_DB:=}
+      user: ${env.PGVECTOR_USER:=}
+      password: ${env.PGVECTOR_PASSWORD:=}
   files:
   - provider_id: meta-reference-files
     provider_type: inline::localfs
@@ -156,17 +156,17 @@ providers:
   - provider_id: braintrust
     provider_type: inline::braintrust
     config:
-      openai_api_key: ${env.OPENAI_API_KEY:+}
+      openai_api_key: ${env.OPENAI_API_KEY:=}
   tool_runtime:
   - provider_id: brave-search
     provider_type: remote::brave-search
     config:
-      api_key: ${env.BRAVE_SEARCH_API_KEY:+}
+      api_key: ${env.BRAVE_SEARCH_API_KEY:=}
       max_results: 3
   - provider_id: tavily-search
     provider_type: remote::tavily-search
     config:
-      api_key: ${env.TAVILY_SEARCH_API_KEY:+}
+      api_key: ${env.TAVILY_SEARCH_API_KEY:=}
       max_results: 3
   - provider_id: rag-runtime
     provider_type: inline::rag-runtime

llama_stack/templates/starter/starter.py

@@ -72,17 +72,17 @@ def get_inference_providers() -> tuple[list[Provider], dict[str, list[ProviderMo
         (
             "openai",
             OPENAI_MODEL_ENTRIES,
-            OpenAIConfig.sample_run_config(api_key="${env.OPENAI_API_KEY:+}"),
+            OpenAIConfig.sample_run_config(api_key="${env.OPENAI_API_KEY:=}"),
         ),
         (
             "fireworks",
             FIREWORKS_MODEL_ENTRIES,
-            FireworksImplConfig.sample_run_config(api_key="${env.FIREWORKS_API_KEY:+}"),
+            FireworksImplConfig.sample_run_config(api_key="${env.FIREWORKS_API_KEY:=}"),
         ),
         (
             "together",
             TOGETHER_MODEL_ENTRIES,
-            TogetherImplConfig.sample_run_config(api_key="${env.TOGETHER_API_KEY:+}"),
+            TogetherImplConfig.sample_run_config(api_key="${env.TOGETHER_API_KEY:=}"),
         ),
         (
             "ollama",
@@ -106,22 +106,22 @@ def get_inference_providers() -> tuple[list[Provider], dict[str, list[ProviderMo
         (
             "anthropic",
             ANTHROPIC_MODEL_ENTRIES,
-            AnthropicConfig.sample_run_config(api_key="${env.ANTHROPIC_API_KEY:+}"),
+            AnthropicConfig.sample_run_config(api_key="${env.ANTHROPIC_API_KEY:=}"),
         ),
         (
             "gemini",
             GEMINI_MODEL_ENTRIES,
-            GeminiConfig.sample_run_config(api_key="${env.GEMINI_API_KEY:+}"),
+            GeminiConfig.sample_run_config(api_key="${env.GEMINI_API_KEY:=}"),
         ),
         (
             "groq",
             GROQ_MODEL_ENTRIES,
-            GroqConfig.sample_run_config(api_key="${env.GROQ_API_KEY:+}"),
+            GroqConfig.sample_run_config(api_key="${env.GROQ_API_KEY:=}"),
         ),
         (
             "sambanova",
             SAMBANOVA_MODEL_ENTRIES,
-            SambaNovaImplConfig.sample_run_config(api_key="${env.SAMBANOVA_API_KEY:+}"),
+            SambaNovaImplConfig.sample_run_config(api_key="${env.SAMBANOVA_API_KEY:=}"),
         ),
         (
             "vllm",
@@ -190,15 +190,15 @@ def get_distribution_template() -> DistributionTemplate:
         Provider(
             provider_id="${env.ENABLE_CHROMADB:+chromadb}",
             provider_type="remote::chromadb",
-            config=ChromaVectorIOConfig.sample_run_config(url="${env.CHROMADB_URL:+}"),
+            config=ChromaVectorIOConfig.sample_run_config(url="${env.CHROMADB_URL:=}"),
         ),
         Provider(
             provider_id="${env.ENABLE_PGVECTOR:+pgvector}",
             provider_type="remote::pgvector",
             config=PGVectorVectorIOConfig.sample_run_config(
-                db="${env.PGVECTOR_DB:+}",
-                user="${env.PGVECTOR_USER:+}",
-                password="${env.PGVECTOR_PASSWORD:+}",
+                db="${env.PGVECTOR_DB:=}",
+                user="${env.PGVECTOR_USER:=}",
+                password="${env.PGVECTOR_PASSWORD:=}",
             ),
         ),
     ]