GET url with exponential back-off retry on 429 / 5xx / network errors. Throws ImfHttpError on non-OK responses.
The extraHeaders map is the auth boundary: Datamapper transport passes {} (no subscription key) and SDMX transport injects the Ocp-Apim-Subscription-Key header here. This helper itself does NOT validate the contents of extraHeaders — the "Datamapper transport never carries an SDMX subscription key" convention is enforced at the call sites (see scripts/imf/transport/datamapper.ts) and asserted by the "IMF SDMX subscription key auth boundary" static-source scan in tests/imf/refactor-invariants.test.ts.
GET
urlwith exponential back-off retry on 429 / 5xx / network errors. Throws ImfHttpError on non-OK responses.The
extraHeadersmap is the auth boundary: Datamapper transport passes{}(no subscription key) and SDMX transport injects theOcp-Apim-Subscription-Keyheader here. This helper itself does NOT validate the contents ofextraHeaders— the "Datamapper transport never carries an SDMX subscription key" convention is enforced at the call sites (seescripts/imf/transport/datamapper.ts) and asserted by the "IMF SDMX subscription key auth boundary" static-source scan intests/imf/refactor-invariants.test.ts.