fix: character and bit columns with fixed length not inserting/updating properly

Fixes the error "value too long for type character(1)" when the char length of the column was bigger than one.

CHANGELOG.md

@@ -30,6 +30,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
  - #2840, Fix `Prefer: missing=default` with DOMAIN default values - @steve-chavez
  - #2849, Fix HEAD unnecessarily executing aggregates - @steve-chavez
  - #2594, Fix unused index on jsonb/jsonb arrow filter and order (``/bets?data->>contractId=eq.1`` and ``/bets?order=data->>contractId``) - @steve-chavez
+ - #2861, Fix character and bit columns with fixed length not inserting/updating properly - @laurenceisla
+   + Fixes the error "value too long for type character(1)" when the char length of the column was bigger than one.
 
 ## [11.1.0] - 2023-06-07
 

src/PostgREST/SchemaCache.hs

@@ -573,19 +573,19 @@ tablesSqlQuery pgVer =
           d.description AS description,
   |] <> columnDefault <> [q| AS column_default,
           not (a.attnotnull OR t.typtype = 'd' AND t.typnotnull) AS is_nullable,
+          CASE
+              WHEN t.typtype = 'd' THEN
               CASE
-                  WHEN t.typtype = 'd' THEN
-                  CASE
-                      WHEN nbt.nspname = 'pg_catalog'::name THEN format_type(t.typbasetype, NULL::integer)
-                      ELSE format_type(a.atttypid, a.atttypmod)
-                  END
-                  ELSE
-                  CASE
-                      WHEN nt.nspname = 'pg_catalog'::name THEN format_type(a.atttypid, NULL::integer)
-                      ELSE format_type(a.atttypid, a.atttypmod)
-                  END
-              END::text AS data_type,
-          t.oid AS data_type_id,
+                  WHEN nbt.nspname = 'pg_catalog'::name THEN format_type(t.typbasetype, NULL::integer)
+                  ELSE format_type(a.atttypid, a.atttypmod)
+              END
+              ELSE
+              CASE
+                  WHEN nt.nspname = 'pg_catalog'::name THEN format_type(a.atttypid, NULL::integer)
+                  ELSE format_type(a.atttypid, a.atttypmod)
+              END
+          END::text AS data_type,
+          format_type(a.atttypid, a.atttypmod)::text AS nominal_data_type,
           information_schema._pg_char_max_length(
               information_schema._pg_truetypid(a.*, t.*),
               information_schema._pg_truetypmod(a.*, t.*)
@@ -627,7 +627,7 @@ tablesSqlQuery pgVer =
           info.description,
           info.is_nullable::boolean,
           info.data_type,
-          info.data_type_id::regtype::text,
+          info.nominal_data_type,
           info.character_maximum_length,
           info.column_default,
           coalesce(enum_info.vals, '{}')) order by info.position) as columns

test/spec/Feature/Query/InsertSpec.hs

@@ -391,6 +391,22 @@ spec actualPgVersion = do
           `shouldRespondWith` [json|[{ id: 20 }]|]
             { matchStatus  = 201 }
 
+    -- https://github.com/PostgREST/postgrest/issues/2861
+    context "bit and char columns with length" $ do
+      it "should insert to a bit column with length" $
+        request methodPost "/bitchar_with_length?select=bit"
+            [("Prefer", "return=representation")]
+            [json|{"bit": "10101"}|]
+          `shouldRespondWith` [json|[{ "bit": "10101" }]|]
+            { matchStatus  = 201 }
+
+      it "should insert to a char column with length" $
+        request methodPost "/bitchar_with_length?select=char"
+            [("Prefer", "return=representation")]
+            [json|{"char": "abcde"}|]
+          `shouldRespondWith` [json|[{ "char": "abcde" }]|]
+            { matchStatus  = 201 }
+
     context "POST with ?columns parameter" $ do
       it "ignores json keys not included in ?columns" $ do
         request methodPost "/articles?columns=id,body" [("Prefer", "return=representation")]

test/spec/Feature/Query/UpdateSpec.hs

@@ -384,6 +384,22 @@ spec actualPgVersion = do
             , matchHeaders = ["Preference-Applied" <:> "missing=default"]
             }
 
+    -- https://github.com/PostgREST/postgrest/issues/2861
+    context "bit and char columns with length" $ do
+      it "should update a bit column with length" $
+        request methodPatch "/bitchar_with_length?char=eq.aaaaa"
+            [("Prefer", "return=representation")]
+            [json|{"bit": "11100"}|]
+          `shouldRespondWith` [json|[{ "bit": "11100", "char": "aaaaa" }]|]
+            { matchStatus  = 200 }
+
+      it "should update a char column with length" $
+        request methodPatch "/bitchar_with_length?bit=eq.00000"
+            [("Prefer", "return=representation")]
+            [json|{"char": "zzzyy"}|]
+          `shouldRespondWith` [json|[{ "bit": "00000", "char": "zzzyy" }]|]
+            { matchStatus  = 200 }
+
   context "tables with self reference foreign keys" $ do
     context "embeds children after update" $ do
       it "without filters" $

test/spec/fixtures/data.sql

@@ -849,3 +849,7 @@ INSERT INTO datarep_todos VALUES (4, 'Opus Magnum', NULL, NULL);
 TRUNCATE TABLE datarep_next_two_todos CASCADE;
 INSERT INTO datarep_next_two_todos VALUES (1, 2, 3, 'school related');
 INSERT INTO datarep_next_two_todos VALUES (2, 1, 3, 'do these first');
+
+TRUNCATE TABLE bitchar_with_length CASCADE;
+INSERT INTO bitchar_with_length(bit, char) VALUES ('00000', 'aaaaa');
+INSERT INTO bitchar_with_length(bit, char) VALUES ('11111', 'bbbbb');

test/spec/fixtures/schema.sql

@@ -3302,3 +3302,9 @@ create table bets (
 
 create index bets_data_json  on bets ((data_json  ->>'contractId'));
 create index bets_data_jsonb on bets ((data_jsonb ->>'contractId'));
+
+-- https://github.com/PostgREST/postgrest/issues/2861
+CREATE TABLE bitchar_with_length (
+  bit bit(5),
+  char char(5)
+);