graphql-engine/server/src-lib/Hasura/Tracing/Utils.hs
2023-05-31 05:49:12 +00:00

58 lines
2.3 KiB
Haskell

-- | This module contains a collection of utility functions we use with tracing
-- throughout the codebase, but that are not a core part of the library. If we
-- were to move tracing to a separate library, those functions should be kept
-- here in the core engine code.
module Hasura.Tracing.Utils
( traceHTTPRequest,
attachSourceConfigAttributes,
)
where
import Control.Lens
import Data.String
import Data.Text.Extended (toTxt)
import Hasura.Prelude
import Hasura.RQL.Types.SourceConfiguration (HasSourceConfiguration (..))
import Hasura.Tracing.Class
import Hasura.Tracing.Context
import Hasura.Tracing.Sampling
import Hasura.Tracing.TraceId
import Network.HTTP.Client.Transformable qualified as HTTP
-- | Wrap the execution of an HTTP request in a span in the current
-- trace. Despite its name, this function does not start a new trace, and the
-- span will therefore not be recorded if the surrounding context isn't traced
-- (see 'spanWith').
--
-- Additionally, this function adds metadata regarding the request to the
-- created span, and injects the trace context into the HTTP header.
traceHTTPRequest ::
(MonadIO m, MonadTrace m) =>
-- | http request that needs to be made
HTTP.Request ->
-- | a function that takes the traced request and executes it
(HTTP.Request -> m a) ->
m a
traceHTTPRequest req f = do
let method = bsToTxt (view HTTP.method req)
uri = view HTTP.url req
newSpan (method <> " " <> uri) do
let reqBytes = HTTP.getReqSize req
attachMetadata [("request_body_bytes", fromString (show reqBytes))]
headers <- fmap (maybe [] toHeaders) currentContext
f $ over HTTP.headers (headers <>) req
where
toHeaders :: TraceContext -> [HTTP.Header]
toHeaders TraceContext {..} =
catMaybes
[ Just ("X-B3-TraceId", traceIdToHex tcCurrentTrace),
Just ("X-B3-SpanId", spanIdToHex tcCurrentSpan),
("X-B3-ParentSpanId",) . spanIdToHex <$> tcCurrentParent,
("X-B3-Sampled",) <$> samplingStateToHeader tcSamplingState
]
attachSourceConfigAttributes :: forall b m. (HasSourceConfiguration b, MonadTrace m) => SourceConfig b -> m ()
attachSourceConfigAttributes sourceConfig = do
let backendSourceKind = sourceConfigBackendSourceKind @b sourceConfig
attachMetadata [("source.kind", toTxt $ backendSourceKind)]