From 9254f119f68f7403fe3c766ef6f6eb741d0b82bf Mon Sep 17 00:00:00 2001
From: Wolfgang Walther <walther@technowledgy.de>
Date: Sat, 5 Dec 2020 20:25:55 +0100
Subject: [PATCH] fix: implement robust parsing of boolean config values

resolves #1572
---
 src/PostgREST/Config.hs                       | 19 ++++++++++-----
 test/io-tests/configs/boolean-numeric.config  |  7 ++++++
 test/io-tests/configs/boolean-string.config   |  7 ++++++
 .../configs/expected/boolean-numeric.config   | 24 +++++++++++++++++++
 .../configs/expected/boolean-string.config    | 24 +++++++++++++++++++
 5 files changed, 75 insertions(+), 6 deletions(-)
 create mode 100644 test/io-tests/configs/boolean-numeric.config
 create mode 100644 test/io-tests/configs/boolean-string.config
 create mode 100644 test/io-tests/configs/expected/boolean-numeric.config
 create mode 100644 test/io-tests/configs/expected/boolean-string.config

diff --git a/src/PostgREST/Config.hs b/src/PostgREST/Config.hs
index 066486bc2..47ea6156c 100644
--- a/src/PostgREST/Config.hs
+++ b/src/PostgREST/Config.hs
@@ -42,9 +42,10 @@ import Data.Aeson              (encode, toJSON)
 import Data.Either.Combinators (fromRight', whenLeft)
 import Data.List.NonEmpty      (fromList, toList)
 import Data.Scientific         (floatingOrInteger)
-import Data.Text               (dropEnd, dropWhileEnd, intercalate,
-                                pack, replace, splitOn, strip,
-                                stripPrefix, take, toLower, unpack)
+import Data.Text               (dropEnd, dropWhileEnd, filter,
+                                intercalate, pack, replace, splitOn,
+                                strip, stripPrefix, take, toLower,
+                                toTitle, unpack)
 import Data.Text.IO            (hPutStrLn)
 import Data.Version            (versionBranch)
 import Development.GitRev      (gitHash)
@@ -64,9 +65,10 @@ import PostgREST.Parsers          (pRoleClaimKey)
 import PostgREST.Private.ProxyUri (isMalformedProxyUri)
 import PostgREST.Types            (JSPath, JSPathExp (..),
                                    LogLevel (..))
-import Protolude                  hiding (concat, hPutStrLn,
+import Protolude                  hiding (concat, filter, hPutStrLn,
                                    intercalate, null, replace, take,
-                                   toList, toLower, toS, (<>))
+                                   toList, toLower, toS, toTitle,
+                                   (<>))
 import Protolude.Conv             (toS)
 
 -- | Command line interface options
@@ -429,7 +431,12 @@ readAppConfig cfgPath = do
 
     coerceBool :: C.Value -> Maybe Bool
     coerceBool (C.Bool b)   = Just b
-    coerceBool (C.String b) = readMaybe $ toS b
+    coerceBool (C.String s) =
+      -- parse all kinds of text: True, true, TRUE, "true", ...
+      case readMaybe . toS $ toTitle $ filter isAlpha $ toS s of
+        Just b  -> Just b
+        -- numeric instead?
+        Nothing -> (> 0) <$> (readMaybe $ toS s :: Maybe Integer)
     coerceBool _            = Nothing
 
     parseRoleClaimKey :: C.Value -> Either Text JSPath
diff --git a/test/io-tests/configs/boolean-numeric.config b/test/io-tests/configs/boolean-numeric.config
new file mode 100644
index 000000000..6dbe6c88e
--- /dev/null
+++ b/test/io-tests/configs/boolean-numeric.config
@@ -0,0 +1,7 @@
+db-uri = "required"
+db-schemas = "required"
+db-anon-role = "required"
+
+db-channel-enabled = "1"
+db-prepared-statements = "0"
+jwt-secret-is-base64 = "2"
diff --git a/test/io-tests/configs/boolean-string.config b/test/io-tests/configs/boolean-string.config
new file mode 100644
index 000000000..f7967cd4f
--- /dev/null
+++ b/test/io-tests/configs/boolean-string.config
@@ -0,0 +1,7 @@
+db-uri = "required"
+db-schemas = "required"
+db-anon-role = "required"
+
+db-channel-enabled = "true"
+db-prepared-statements = "FALSE"
+jwt-secret-is-base64 = "\"true\""
diff --git a/test/io-tests/configs/expected/boolean-numeric.config b/test/io-tests/configs/expected/boolean-numeric.config
new file mode 100644
index 000000000..d5460e7de
--- /dev/null
+++ b/test/io-tests/configs/expected/boolean-numeric.config
@@ -0,0 +1,24 @@
+db-anon-role = "required"
+db-channel = "pgrst"
+db-channel-enabled = true
+db-extra-search-path = "public"
+db-max-rows = ""
+db-pool = 10
+db-pool-timeout = 10
+db-pre-request = ""
+db-prepared-statements = false
+db-root-spec = ""
+db-schemas = "required"
+db-tx-end = "commit"
+db-uri = "required"
+jwt-aud = ""
+jwt-role-claim-key = ".\"role\""
+jwt-secret = ""
+jwt-secret-is-base64 = true
+log-level = "error"
+openapi-server-proxy-uri = ""
+raw-media-types = ""
+server-host = "!4"
+server-port = 3000
+server-unix-socket = ""
+server-unix-socket-mode = "660"
diff --git a/test/io-tests/configs/expected/boolean-string.config b/test/io-tests/configs/expected/boolean-string.config
new file mode 100644
index 000000000..d5460e7de
--- /dev/null
+++ b/test/io-tests/configs/expected/boolean-string.config
@@ -0,0 +1,24 @@
+db-anon-role = "required"
+db-channel = "pgrst"
+db-channel-enabled = true
+db-extra-search-path = "public"
+db-max-rows = ""
+db-pool = 10
+db-pool-timeout = 10
+db-pre-request = ""
+db-prepared-statements = false
+db-root-spec = ""
+db-schemas = "required"
+db-tx-end = "commit"
+db-uri = "required"
+jwt-aud = ""
+jwt-role-claim-key = ".\"role\""
+jwt-secret = ""
+jwt-secret-is-base64 = true
+log-level = "error"
+openapi-server-proxy-uri = ""
+raw-media-types = ""
+server-host = "!4"
+server-port = 3000
+server-unix-socket = ""
+server-unix-socket-mode = "660"