Change uri_path to return text

README.md

@@ -88,6 +88,19 @@ A number of functions are provided to extract parts of a URI:
     Extracts the port of a URI as an integer, for example `5432`.  If
     no port is specified, the return value is null.
 
+- `uri_path(uri) returns text`
+
+    Extracts the path component of a URI.  Logically, a URI always
+    contains a path.  The return value can be an empty string but
+    never null.
+
+- `uri_path_array(uri) returns text[]`
+
+    Returns the path component of a URI as an array, with the path
+    split at the slash characters.  This is probably not as useful as
+    the `uri_path` function, but it is provided here because the
+    `uriparser` library exposes it.
+
 - `uri_query(uri) returns text`
 
     Extracts the query part of a URI (roughly speaking, everything

test/expected/test.out

@@ -13,7 +13,9 @@ VALUES ('http://www.postgresql.org/'),
        ('http://[1080::8:800:200C:417A]/foo'),
        ('http://host:'),
        (''),
-       ('foobar');
+       ('/'),
+       ('foobar'),
+       ('/foobar');
 SELECT * FROM test;
  a  |                                            b                                            
 ----+-----------------------------------------------------------------------------------------
@@ -28,8 +30,10 @@ SELECT * FROM test;
   9 | http://[1080::8:800:200C:417A]/foo
  10 | http://host:
  11 | 
- 12 | foobar
+ 12 | /
-(12 rows)
+ 13 | foobar
+ 14 | /foobar
+(14 rows)
 
 -- error cases
 SELECT uri 'http://host:port/';
@@ -44,127 +48,162 @@ SELECT b AS uri,
        uri_host_inet(b),
        uri_port(b),
        uri_path(b),
+       uri_path_array(b),
        uri_query(b),
        uri_fragment(b)
   FROM test;
--[ RECORD 1 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 1 ]--+----------------------------------------------------------------------------------------
 uri            | http://www.postgresql.org/
 uri_scheme     | http
 uri_userinfo   | _null_
 uri_host       | www.postgresql.org
 uri_host_inet  | _null_
 uri_port       | _null_
-uri_path      | {""}
+uri_path       | /
+uri_path_array | {""}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 2 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 2 ]--+----------------------------------------------------------------------------------------
 uri            | http://www.postgresql.org/docs/devel/static/xfunc-sql.html#XFUNC-SQL-FUNCTION-ARGUMENTS
 uri_scheme     | http
 uri_userinfo   | _null_
 uri_host       | www.postgresql.org
 uri_host_inet  | _null_
 uri_port       | _null_
-uri_path      | {docs,devel,static,xfunc-sql.html}
+uri_path       | /docs/devel/static/xfunc-sql.html
+uri_path_array | {docs,devel,static,xfunc-sql.html}
 uri_query      | _null_
 uri_fragment   | XFUNC-SQL-FUNCTION-ARGUMENTS
--[ RECORD 3 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 3 ]--+----------------------------------------------------------------------------------------
 uri            | https://duckduckgo.com/?q=postgresql&ia=about
 uri_scheme     | https
 uri_userinfo   | _null_
 uri_host       | duckduckgo.com
 uri_host_inet  | _null_
 uri_port       | _null_
-uri_path      | {""}
+uri_path       | /
+uri_path_array | {""}
 uri_query      | q=postgresql&ia=about
 uri_fragment   | _null_
--[ RECORD 4 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 4 ]--+----------------------------------------------------------------------------------------
 uri            | ftp://ftp.gnu.org/gnu/bison
 uri_scheme     | ftp
 uri_userinfo   | _null_
 uri_host       | ftp.gnu.org
 uri_host_inet  | _null_
 uri_port       | _null_
-uri_path      | {gnu,bison}
+uri_path       | /gnu/bison
+uri_path_array | {gnu,bison}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 5 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 5 ]--+----------------------------------------------------------------------------------------
 uri            | mailto:foo@example.com
 uri_scheme     | mailto
 uri_userinfo   | _null_
 uri_host       | _null_
 uri_host_inet  | _null_
 uri_port       | _null_
-uri_path      | {foo@example.com}
+uri_path       | foo@example.com
+uri_path_array | {foo@example.com}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 6 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 6 ]--+----------------------------------------------------------------------------------------
 uri            | ssh://username@review.openstack.org:29418/openstack/nova.git
 uri_scheme     | ssh
 uri_userinfo   | username
 uri_host       | review.openstack.org
 uri_host_inet  | _null_
 uri_port       | 29418
-uri_path      | {openstack,nova.git}
+uri_path       | /openstack/nova.git
+uri_path_array | {openstack,nova.git}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 7 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 7 ]--+----------------------------------------------------------------------------------------
 uri            | http://admin:password@192.168.0.1
 uri_scheme     | http
 uri_userinfo   | admin:password
 uri_host       | 192.168.0.1
 uri_host_inet  | 192.168.0.1
 uri_port       | _null_
-uri_path      | {}
+uri_path       | 
+uri_path_array | {}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 8 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 8 ]--+----------------------------------------------------------------------------------------
 uri            | http://[FEDC:BA98:7654:3210:FEDC:BA98:7654:3210]:80/index.html
 uri_scheme     | http
 uri_userinfo   | _null_
 uri_host       | FEDC:BA98:7654:3210:FEDC:BA98:7654:3210
 uri_host_inet  | fedc:ba98:7654:3210:fedc:ba98:7654:3210
 uri_port       | 80
-uri_path      | {index.html}
+uri_path       | /index.html
+uri_path_array | {index.html}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 9 ]-+----------------------------------------------------------------------------------------
+-[ RECORD 9 ]--+----------------------------------------------------------------------------------------
 uri            | http://[1080::8:800:200C:417A]/foo
 uri_scheme     | http
 uri_userinfo   | _null_
 uri_host       | 1080::8:800:200C:417A
 uri_host_inet  | 1080::8:800:200c:417a
 uri_port       | _null_
-uri_path      | {foo}
+uri_path       | /foo
+uri_path_array | {foo}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 10 ]+----------------------------------------------------------------------------------------
+-[ RECORD 10 ]-+----------------------------------------------------------------------------------------
 uri            | http://host:
 uri_scheme     | http
 uri_userinfo   | _null_
 uri_host       | host
 uri_host_inet  | _null_
 uri_port       | _null_
-uri_path      | {}
+uri_path       | 
+uri_path_array | {}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 11 ]+----------------------------------------------------------------------------------------
+-[ RECORD 11 ]-+----------------------------------------------------------------------------------------
 uri            | 
 uri_scheme     | _null_
 uri_userinfo   | _null_
 uri_host       | _null_
 uri_host_inet  | _null_
 uri_port       | _null_
-uri_path      | {}
+uri_path       | 
+uri_path_array | {}
 uri_query      | _null_
 uri_fragment   | _null_
--[ RECORD 12 ]+----------------------------------------------------------------------------------------
+-[ RECORD 12 ]-+----------------------------------------------------------------------------------------
+uri            | /
+uri_scheme     | _null_
+uri_userinfo   | _null_
+uri_host       | _null_
+uri_host_inet  | _null_
+uri_port       | _null_
+uri_path       | /
+uri_path_array | {}
+uri_query      | _null_
+uri_fragment   | _null_
+-[ RECORD 13 ]-+----------------------------------------------------------------------------------------
 uri            | foobar
 uri_scheme     | _null_
 uri_userinfo   | _null_
 uri_host       | _null_
 uri_host_inet  | _null_
 uri_port       | _null_
-uri_path      | {foobar}
+uri_path       | foobar
+uri_path_array | {foobar}
+uri_query      | _null_
+uri_fragment   | _null_
+-[ RECORD 14 ]-+----------------------------------------------------------------------------------------
+uri            | /foobar
+uri_scheme     | _null_
+uri_userinfo   | _null_
+uri_host       | _null_
+uri_host_inet  | _null_
+uri_port       | _null_
+uri_path       | /foobar
+uri_path_array | {foobar}
 uri_query      | _null_
 uri_fragment   | _null_
 
@@ -173,6 +212,8 @@ SELECT DISTINCT b FROM test ORDER BY b;
                                             b                                            
 -----------------------------------------------------------------------------------------
  
+ /
+ /foobar
  foobar
  ftp://ftp.gnu.org/gnu/bison
  http://[1080::8:800:200C:417A]/foo
@@ -184,5 +225,5 @@ SELECT DISTINCT b FROM test ORDER BY b;
  https://duckduckgo.com/?q=postgresql&ia=about
  mailto:foo@example.com
  ssh://username@review.openstack.org:29418/openstack/nova.git
-(12 rows)
+(14 rows)
 

test/sql/test.sql

@@ -16,7 +16,9 @@ VALUES ('http://www.postgresql.org/'),
        ('http://[1080::8:800:200C:417A]/foo'),
        ('http://host:'),
        (''),
-       ('foobar');
+       ('/'),
+       ('foobar'),
+       ('/foobar');
 
 SELECT * FROM test;
 
@@ -32,6 +34,7 @@ SELECT b AS uri,
        uri_host_inet(b),
        uri_port(b),
        uri_path(b),
+       uri_path_array(b),
        uri_query(b),
        uri_fragment(b)
   FROM test;

uri.c

@@ -1,6 +1,7 @@
 #include <postgres.h>
 #include <catalog/pg_type.h>
 #include <fmgr.h>
+#include <lib/stringinfo.h>
 #include <utils/array.h>
 #include <utils/builtins.h>
 #include <utils/inet.h>
@@ -223,6 +224,34 @@ uri_fragment(PG_FUNCTION_ARGS)
 PG_FUNCTION_INFO_V1(uri_path);
 Datum
 uri_path(PG_FUNCTION_ARGS)
+{
+	Datum arg = PG_GETARG_DATUM(0);
+	char *s = TextDatumGetCString(arg);
+	UriUriA uri;
+	StringInfoData buf;
+	UriPathSegmentA *p;
+
+	initStringInfo(&buf);
+
+	parse_uri(s, &uri);
+
+	if (uri.absolutePath || (uriIsHostSetA(&uri) && uri.pathHead))
+		appendStringInfoChar(&buf, '/');
+
+	for (p = uri.pathHead; p; p = p->next)
+	{
+		appendBinaryStringInfo(&buf, p->text.first, p->text.afterLast - p->text.first);
+		if (p->next)
+			appendStringInfoChar(&buf, '/');
+	}
+
+	uriFreeUriMembersA(&uri);
+	PG_RETURN_TEXT_P(cstring_to_text(buf.data));
+}
+
+PG_FUNCTION_INFO_V1(uri_path_array);
+Datum
+uri_path_array(PG_FUNCTION_ARGS)
 {
 	Datum arg = PG_GETARG_DATUM(0);
 	char *s = TextDatumGetCString(arg);

uri.sql

@@ -68,7 +68,13 @@ CREATE FUNCTION uri_fragment(uri) RETURNS text
     LANGUAGE C
     AS '$libdir/uri';
 
-CREATE FUNCTION uri_path(uri) RETURNS text[]
+CREATE FUNCTION uri_path(uri) RETURNS text
+    IMMUTABLE
+    STRICT
+    LANGUAGE C
+    AS '$libdir/uri';
+
+CREATE FUNCTION uri_path_array(uri) RETURNS text[]
     IMMUTABLE
     STRICT
     LANGUAGE C