Within a C++ EnvoyFilter I need to make a SYNCHRONOUS http call to an upstream host. The SDK offers “httpCall” function: https://github.com/proxy-wasm/proxy-wasm-cpp-sdk/blob/c17bf8257e5ebad2399f95cc15c8ff64e515519f/docs/wasm_filter.md#httpcall
However, the “callback” of “httpCall” function is ASYNC.
Is there a way to make a SYNCHRONOUS http call instead?