Return NULL on non-existant JSON fields. Fixes #3

theirix · Oct 29, 2012 · a888cc7 · a888cc7
1 parent ac27d4d
commit a888cc7
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Showing 4 changed files with 18 additions and 6 deletions.
diff --git a/Makefile b/Makefile
@@ -6,7 +6,7 @@ DATA         = $(wildcard sql/*--*.sql) sql/$(EXTENSION)--$(EXTVERSION).sql
 DOCS         = $(wildcard doc/*.md)
 TESTS        = $(wildcard test/sql/*.sql)
 REGRESS      = $(patsubst test/sql/%.sql,%,$(TESTS))
-REGRESS_OPTS = --inputdir=test
+REGRESS_OPTS += --inputdir=test
 PG_CONFIG    := pg_config
 #PG_CPPFLAGS  = 
 EXTRA_CLEAN = sql/$(EXTENSION)--$(EXTVERSION).sql

diff --git a/src/json_accessors.c b/src/json_accessors.c
@@ -189,9 +189,10 @@ ArrayType* construct_typed_array(Datum *elems, int nelems, Oid elmtype)
  */
 Datum json_object_get_generic(text *argJson, text *argKey, int json_type, pextract_type_from_json extractor)
 {
-	Datum result;
+	Datum result = (Datum)0;
 	char *strJson, *strKey;
 	cJSON *root, *sel;
+	bool valid = false;
 
 	strJson = text_to_cstring(argJson);
 	strKey = text_to_cstring(argKey);
@@ -211,6 +212,7 @@ Datum json_object_get_generic(text *argJson, text *argKey, int json_type, pextra
 							 errmsg("type extractor refused to parse object type %s",
 								 json_type_str(json_type))));
 				}
+				valid = true;
 			}
 			else
 			{
@@ -222,10 +224,11 @@ Datum json_object_get_generic(text *argJson, text *argKey, int json_type, pextra
 		}
 		else
 		{
-			ereport(ERROR,
+			valid = true;
+			/*ereport(ERROR,
 					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 					 errmsg("cannot extract from \"%s\" json object by the key \"%s\"",
-						 	strJson, strKey)));
+						 	strJson, strKey)));*/
 		}
 		cJSON_Delete(root);
 	}
@@ -239,7 +242,7 @@ Datum json_object_get_generic(text *argJson, text *argKey, int json_type, pextra
 	pfree(strJson);
 	pfree(strKey);
 
-	if (!result)
+	if (!valid)
 		ereport(ERROR,
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 				 errmsg("json string cannot be parsed")));
@@ -252,7 +255,11 @@ Datum json_object_get_generic(text *argJson, text *argKey, int json_type, pextra
  */
 Datum json_object_get_generic_args(PG_FUNCTION_ARGS, int json_type, pextract_type_from_json extractor)
 {
-	return json_object_get_generic(PG_GETARG_TEXT_P(0), PG_GETARG_TEXT_P(1), json_type, extractor);
+	Datum result = json_object_get_generic(PG_GETARG_TEXT_P(0), PG_GETARG_TEXT_P(1), json_type, extractor);
+	if (result)
+		PG_RETURN_DATUM(result);
+	else
+		PG_RETURN_NULL();
 }
 
 /*

diff --git a/test/expected/regress.out b/test/expected/regress.out
@@ -22,6 +22,9 @@ select json_get_bigint('{"baz": 9223372036854, "boo": 42.424242}', 'baz');
 -- 42.424242
 select json_get_numeric('{"baz": 42, "boo": 42.424242}', 'boo');
 42.424242
+-- t
+select json_get_text('{"foo":"qq", "bar": true}', 'noneofthese') is null;
+t
 -- Tue Dec 01 01:23:45 2009
 select json_get_timestamp('{"foo":"qq", "bar": "2009-12-01 01:23:45"}', 'bar');
 Tue Dec 01 01:23:45 2009

diff --git a/test/sql/regress.sql b/test/sql/regress.sql
@@ -18,6 +18,8 @@ select json_get_bigint('{"baz": 42, "boo": 42.424242}', 'baz');
 select json_get_bigint('{"baz": 9223372036854, "boo": 42.424242}', 'baz');
 -- 42.424242
 select json_get_numeric('{"baz": 42, "boo": 42.424242}', 'boo');
+-- t
+select json_get_text('{"foo":"qq", "bar": true}', 'noneofthese') is null;
 
 -- Tue Dec 01 01:23:45 2009
 select json_get_timestamp('{"foo":"qq", "bar": "2009-12-01 01:23:45"}', 'bar');