oss_25_declarative_config_configprovider_create

[ocelotl]

Closes #38

Declarative config: add a stateless create(model) -> Providers that builds providers without mutating globals (configure_sdk() now delegates to it then installs globals), plus ConfigProperties/ConfigProvider typed read view over the .instrumentation node (Linear OSS-25, finding L8).

Validation: scope contained to opentelemetry-configuration + changelog; package suite 392 passed.

Linear issue: https://linear.app/dash0/issue/OSS-25/l8-declarative-config-no-configproviderconfigproperties-api-no-pure

[ocelotl]

🔒 Internal (dash0) — not for upstream.

• Linear: https://linear.app/dash0/issue/OSS-25/l8-declarative-config-no-configproviderconfigproperties-api-no-pure (finding L8)
• Closes: oss_25_declarative_config_configprovider_create #38 · Branch: oss_25_declarative_config_configprovider_create · Commit: 1834b27a8
• Validation: package suite 392 passed; scope configuration + changelog. Rewrote 3 pre-existing configure_sdk tests; _sdk.py overlaps OSS-24/oss_24_declarative_config_present_null_defaults #34 and OSS-26/oss_26_declarative_config_env_substitution #36 (merge order).

[ocelotl]

📣 Public-facing draft — to be used for the upstream PR in open-telemetry/opentelemetry-python. No internal references; copy verbatim.

Title: Add pure create() and ConfigProvider/ConfigProperties to declarative config

What

Adds a stateless create(model) -> Providers to opentelemetry-configuration and a ConfigProvider / ConfigProperties API for reading declarative instrumentation config.

• create(config) builds the tracer/meter/logger providers, the propagator, and a ConfigProvider from a parsed OpenTelemetryConfiguration, returning them in a Providers bundle without touching global state. Absent sections yield None providers (spec "noop default"); the propagator is always built.
• configure_sdk(config) now delegates to create(), then installs the built providers as process globals and runs instrumentation. Behavior unchanged for existing callers.
• ConfigProperties wraps the parsed .instrumentation node with typed getters (get_string, get_bool, get_int, get_float, get_config, get_config_list, get_scalar_list, keys), each returning None on missing key or type mismatch. ConfigProvider exposes it via set_config_provider/get_config_provider.

Why

Separates building providers from installing them (enabling embedding and testing without side effects) and gives instrumentation libraries a standard, spec-shaped read view over declarative instrumentation config.

Spec / reference

configuration/api.md (ConfigProvider/ConfigProperties, Stable) and sdk.md; mirrors Java's DeclarativeConfiguration.parse()/create() and DeclarativeConfigProperties.

Tests

New create() tests (providers returned, no global mutation, instrumentation config exposed); new ConfigProperties tests (typed getters + null/type-mismatch); existing configure_sdk tests updated to the new install flow. Full package suite: 392 passed.