Since all paths for the various query services were the same even though
the API was different it was confusing to work with and debug.
Now all internal paths have a unique name.
Moves idpe.QueryService into platform/query.ProxyQueryService
Splits the Request into ProxyRequest and Request.
Changes query.QueryService and query.AsyncQueryService to use a Request
type. This means that the Compiler interface is consumed by the service
to abstract out transpilation vs Flux compilation vs raw spec.
The transpiler handler is removed.
There are separate http handlers and service implementations for each of
the three query services.
Query logging types are moved into platform.
The ResultIterator now expects Cancel to always be called.
The fluxd binary exposes the query endpoint specified in the swagger
file.
This makes it so we can encode errors in HTTP headers so long as the
encoder did not write anything.
This also changes the behavior to encode the stats trailer even in the
event of an error.
Introduces the Statisticser interface which ResultIterators may
implement.
The HTTP implementation uses HTTP trailers to preserve the statistics.
This way we do not need to have all encoders and decoders support
statistics.
This modifies the `MultiResultDecoder` interface to accept an
`io.ReadCloser` so the `ResultIterator` can close the `io.Reader`
instead of doing it through a defer call. It then makes it so the
`Cancel()` method will close the reader or the reader will be
automatically closed when `More()` returns false.
The query service now handles some errors (not all) from the ifqld
service. This way, the transpiler, which uses the query service, can
report when it encounters an error from ifqld.
The transpiler will now correctly return errors in the JSON response.
Lorenzo Fontana
Nathaniel Cook
Stuart Carnie
Chris Goller
Michael Desa
Leonardo Di Donato
Iris Scholten
Jonathan A. Sternberg
Adam