move ENV var export from buildkite script into buildkite configuration

.buildkite/benchmark.sh

@@ -3,20 +3,11 @@
 
 set -euo pipefail
 
-netname="${1-}"
-
-if [ -z "$netname" ]; then
-   echo "usage: benchmark.sh NETWORK"
-   exit 1
-fi
-
 echo "--- Build code and benchmarks"
 stack build --bench --no-run-benchmarks
 
-export NETWORK=$netname
-
-echo "+++ Run benchmarks"
-stack bench cardano-wallet:restore --interleaved-output --ba "$netname +RTS -N2 -qg -A1m -I0 -T -M8G -h -RTS"
+echo "+++ Run benchmarks - $NETWORK"
+stack bench cardano-wallet:restore --interleaved-output --ba "$NETWORK +RTS -N2 -qg -A1m -I0 -T -M8G -h -RTS"
 
 hp2pretty restore.hp
 

.buildkite/nightly.yml

@@ -2,12 +2,16 @@ env:
   NIX_PATH: "channel:nixos-19.03"
 steps:
   - label: 'Restore benchmark - testnet'
-    command: "./.buildkite/benchmark.sh testnet"
+    command: "./.buildkite/benchmark.sh"
     timeout_in_minutes: 60
     agents:
       system: x86_64-linux
+    env:
+      NETWORK: testnet
   - label: 'Restore benchmark - mainnet'
-    command: "./.buildkite/benchmark.sh mainnet"
+    command: "./.buildkite/benchmark.sh"
     timeout_in_minutes: 60
     agents:
       system: x86_64-linux
+    env:
+      NETWORK: mainnet

test/bench/Main.hs

@@ -61,6 +61,8 @@ import Fmt
     ( fmt, (+|), (+||), (|+), (||+) )
 import Say
     ( sayErr )
+import System.Environment
+    ( getArgs, setEnv )
 import System.IO
     ( BufferMode (..), hSetBuffering, stderr, stdout )
 
@@ -77,6 +79,7 @@ main = do
     hSetBuffering stdout NoBuffering
     hSetBuffering stderr NoBuffering
     installSignalHandlers
+    getArgs >>= overrideEnvironment
     prepareNode
     runBenchmarks
         [ bench ("restore " <> toText network <> " seq")
@@ -125,6 +128,17 @@ bench benchName action = do
 printResult :: Text -> Double -> IO ()
 printResult benchName dur = sayErr . fmt $ "  "+|benchName|+": "+|secs dur|+""
 
+-- FIXME This only exists because somehow, in buildkite, we can't pass ENV var
+-- to the haskell executable? There's probably some Nix magic going on and I
+-- don't have time for this.
+overrideEnvironment :: [String] -> IO ()
+overrideEnvironment [network] =
+    setEnv "NETWORK" network
+overrideEnvironment [] =
+    return ()
+overrideEnvironment _ =
+    fail "benchmark expects only one argument to override the '$NETWORK' ENV var"
+
 {-------------------------------------------------------------------------------
                                   Benchmarks
 -------------------------------------------------------------------------------}