maintainers/haskell/hydra-report.hs: work around bulk status timeout

This change adds a flag --slow to hydra-report.sh get-report which
causes it to fetch the cheap evaluation overview endpoint (which only
contains build ids and meta data). The gathered information is then used
to request each build's status individually instead of in bulk which is
very slow, but useful as a last resort if the bulk endpoint times out.

maintainers/scripts/haskell/hydra-report.hs

@@ -30,7 +30,7 @@ Because step 1) is quite expensive and takes roughly ~5 minutes the result is ca
 {-# OPTIONS_GHC -Wall #-}
 {-# LANGUAGE DataKinds #-}
 
-import Control.Monad (forM_, (<=<))
+import Control.Monad (forM_, forM, (<=<))
 import Control.Monad.Trans (MonadIO (liftIO))
 import Data.Aeson (
    FromJSON,
@@ -108,6 +108,7 @@ newtype JobsetEvalInputs = JobsetEvalInputs {nixpkgs :: Nixpkgs}
 data Eval = Eval
    { id :: Int
    , jobsetevalinputs :: JobsetEvalInputs
+   , builds :: Seq Int
    }
    deriving (Generic, ToJSON, FromJSON, Show)
 
@@ -151,18 +152,20 @@ data Build = Build
    }
    deriving (Generic, ToJSON, FromJSON, Show)
 
+data HydraSlownessWorkaroundFlag = HydraSlownessWorkaround | NoHydraSlownessWorkaround
 data RequestLogsFlag = RequestLogs | NoRequestLogs
 
 main :: IO ()
 main = do
    args <- getArgs
    case args of
-      ["get-report"] -> getBuildReports
+      ["get-report", "--slow"] -> getBuildReports HydraSlownessWorkaround
+      ["get-report"] -> getBuildReports NoHydraSlownessWorkaround
       ["ping-maintainers"] -> printMaintainerPing
       ["mark-broken-list", "--no-request-logs"] -> printMarkBrokenList NoRequestLogs
       ["mark-broken-list"] -> printMarkBrokenList RequestLogs
       ["eval-info"] -> printEvalInfo
-      _ -> putStrLn "Usage: get-report | ping-maintainers | mark-broken-list [--no-request-logs] | eval-info"
+      _ -> putStrLn "Usage: get-report [--slow] | ping-maintainers | mark-broken-list [--no-request-logs] | eval-info"
 
 reportFileName :: IO FilePath
 reportFileName = getXdgDirectory XdgCache "haskell-updates-build-report.json"
@@ -170,18 +173,27 @@ reportFileName = getXdgDirectory XdgCache "haskell-updates-build-report.json"
 showT :: Show a => a -> Text
 showT = Text.pack . show
 
-getBuildReports :: IO ()
+getBuildReports :: HydraSlownessWorkaroundFlag -> IO ()
-getBuildReports = runReq defaultHttpConfig do
+getBuildReports opt = runReq defaultHttpConfig do
    evalMay <- Seq.lookup 0 . evals <$> hydraJSONQuery mempty ["jobset", "nixpkgs", "haskell-updates", "evals"]
    eval@Eval{id} <- maybe (liftIO $ fail "No Evalution found") pure evalMay
    liftIO . putStrLn $ "Fetching evaluation " <> show id <> " from Hydra. This might take a few minutes..."
-   buildReports :: Seq Build <- hydraJSONQuery (responseTimeout 600000000) ["eval", showT id, "builds"]
+   buildReports <- getEvalBuilds opt id
    liftIO do
       fileName <- reportFileName
       putStrLn $ "Finished fetching all builds from Hydra, saving report as " <> fileName
       now <- getCurrentTime
       encodeFile fileName (eval, now, buildReports)
 
+getEvalBuilds :: HydraSlownessWorkaroundFlag -> Int -> Req (Seq Build)
+getEvalBuilds NoHydraSlownessWorkaround id =
+  hydraJSONQuery (responseTimeout 600000000) ["eval", showT id, "builds"]
+getEvalBuilds HydraSlownessWorkaround id = do
+  Eval{builds} <- hydraJSONQuery mempty [ "eval", showT id ]
+  forM builds $ \buildId -> do
+    liftIO $ putStrLn $ "Querying build " <> show buildId
+    hydraJSONQuery mempty [ "build", showT buildId ]
+
 hydraQuery :: HttpResponse a => Proxy a -> Option 'Https -> [Text] -> Req (HttpResponseBody a)
 hydraQuery responseType option query =
    responseBody
@@ -190,7 +202,7 @@ hydraQuery responseType option query =
          (foldl' (/:) (https "hydra.nixos.org") query)
          NoReqBody
          responseType
-         (header "User-Agent" "hydra-report.hs/v1 (nixpkgs;maintainers/scripts/haskell)" <> option)
+         (header "User-Agent" "hydra-report.hs/v1 (nixpkgs;maintainers/scripts/haskell) pls fix https://github.com/NixOS/nixos-org-configurations/issues/270" <> option)
 
 hydraJSONQuery :: FromJSON a => Option 'Https -> [Text] -> Req a
 hydraJSONQuery = hydraQuery jsonResponse