postgres=# select * from tablename ; columnname ──────────── 10 (1 row) CREATE OR REPLACE FUNCTION public.foo(x integer) RETURNS integer LANGUAGE plpgsql 1 AS $function$ 2 declare r record; 3 begin 4 if x > 0 then 5 for r in select columnam from tablename 6 loop 7 x := x + r.colname; 8 end loop; 9 end if; 10 return x; 11 end; 12 $function$Function foo contains a two errors - usage of non existing column "columnnam" and reference on non existing field in record "colname". These bugs are not detected when I run function with negative argument:
postgres=# select foo(-1); foo ───── -1 (1 row) Time: 0.352 mswith active plpgsql_lint module, these bugs are diagnosed without dependency on function's parameter value:
postgres=# load 'plpgsql'; LOAD Time: 0.139 ms postgres=# load 'plpgsql_lint'; LOAD Time: 0.137 ms postgres=# select foo(-1); ERROR: column "columnam" does not exist LINE 1: select columnam from tablename ^ QUERY: select columnam from tablename CONTEXT: PL/pgSQL function "foo" line 4 at FOR over SELECT rows -- after fixing FOR statement postgres=# select foo(-1); ERROR: record "r" has no field "colname" CONTEXT: SQL statement "SELECT x + r.colname" PL/pgSQL function "foo" line 6 at assignmentThis module helps to find all errors in code.
It can do a little bit more - it watches a coverage of plpgsql statements in nodes:
you can get a value of coverage tests:
postgres=# select statement_coverage('foo'); statement_coverage ──────────────────── 0.5 (1 row) Time: 0.423 ms postgres=# select decision_coverage('foo'); decision_coverage ─────────────────── 0 (1 row) Time: 0.333 msand you can see, what lines of function was executed:
postgres=# select coverage_get_model('foo'); coverage_get_model ────────────────────────────────────────────────────────────── <blo count="0" lineno="2" stmt="statement block"> <ifs count="1" lineno="3" stmt="IF"> <ift> <lop count="0" lineno="4" stmt="FOR over SELECT rows"> <stm count="0" lineno="6" stmt="assignment"> </stm></lop> </ift> </ifs> <ret count="1" lineno="9" stmt="RETURN"> </ret> </blo> (1 row)
Installation
You have to put code to contrib directory and compile and install from source code. A other installation methods are not supported now:[pavel@pavel-stehule postgresql-9.0.4]$ pwd /home/pavel/src/postgresql-9.0.4 [pavel@pavel-stehule postgresql-9.0.4]$ cd contrib/plpgsql_lint [pavel@pavel-stehule plpgsql_lint]$ make clean rm -f plpgsql_lint.so libplpgsql_lint.a rm -f plpgsql_coverage.so plpgsql_lint.so plpgsql_coverage.o plpgsql_lint.o rm -f plpgsql_lint.sql rm -f plpgsql_coverage.o plpgsql_lint.o [pavel@pavel-stehule plpgsql_lint]$ make all sed 's,MODULE_PATHNAME,$libdir/plpgsql_lint,g' plpgsql_lint.sql.in >plpgsql_lint.sql gcc -O2 -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Wendif-labels -fno-strict-aliasing -fwrapv -g -fpic -fpic -I../../src/pl/plpgsql/src -I. -I. -I../../src/include -D_GNU_SOURCE -I/usr/include/libxml2 -c -o plpgsql_coverage.o plpgsql_coverage.c gcc -O2 -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Wendif-labels -fno-strict-aliasing -fwrapv -g -fpic -fpic -I../../src/pl/plpgsql/src -L../../src/port -Wl,--as-needed -Wl,-rpath,'/usr/local/pgsql90/lib',--enable-new-dtags -shared -o plpgsql_coverage.so plpgsql_coverage.o gcc -O2 -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Wendif-labels -fno-strict-aliasing -fwrapv -g -fpic -fpic -I../../src/pl/plpgsql/src -I. -I. -I../../src/include -D_GNU_SOURCE -I/usr/include/libxml2 -c -o plpgsql_lint.o plpgsql_lint.c gcc -O2 -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Wendif-labels -fno-strict-aliasing -fwrapv -g -fpic -fpic -I../../src/pl/plpgsql/src -shared -o plpgsql_lint.so plpgsql_coverage.o plpgsql_lint.o -L../../src/port -Wl,--as-needed -Wl,-rpath,'/usr/local/pgsql90/lib',--enable-new-dtags [pavel@pavel-stehule plpgsql_lint]$ su Password: [root@pavel-stehule plpgsql_lint]# make install /bin/mkdir -p '/usr/local/pgsql90/lib' /bin/mkdir -p '/usr/local/pgsql90/share/contrib' /bin/mkdir -p '/usr/local/pgsql90/lib' /bin/sh ../../config/install-sh -c -m 755 plpgsql_lint.so '/usr/local/pgsql90/lib/plpgsql_lint.so' /bin/sh ../../config/install-sh -c -m 644 plpgsql_lint.sql '/usr/local/pgsql90/share/contrib' /bin/sh ../../config/install-sh -c -m 755 plpgsql_coverage.so '/usr/local/pgsql90/lib' /bin/sh ../../config/install-sh -c -m 755 plpgsql_lint.so '/usr/local/pgsql90/lib'and in console as user postgres:
test=# load 'plpgsql'; LOAD Time: 0.232 ms test=# \i /usr/local/pgsql90/share/contrib/plpgsql_lint.sql CREATE FUNCTION Time: 21.790 ms CREATE FUNCTION Time: 8.356 ms CREATE FUNCTION Time: 8.145 ms CREATE FUNCTION Time: 8.487 ms test=#After loading module with command LOAD:
test=# load 'plpgsql'; LOAD test=# load 'plpgsql_lint'; LOADthe modul is active.
Limits
It cannot to work with temporary objects - because these objects does not exist when validation is processed.It cannot to work with record variables, that has a value assigned via assign statement:
create or replace function fx(out a int, out b int) as $$ ... $$ DECLARE r record; BEGIN r := fx(); RAISE NOTICE '% %', r.a, r.b; -- this is not possible with plpgsql_lint ...you should to fix function or disable lint:
CREATE TYPE fx_type AS (a int, b int); CREATE OR REPLACE FUNCTION fx() RETURNS fx_type AS $$ .. $$ DECLARE r fx_type; -- don't use combination record and assign statement BEGIN ..Blocking lint of some function is possible via option
test=# CREATE OR REPLACE FUNCTION public.foo(x integer) RETURNS integer LANGUAGE plpgsql AS $function$ declare r record; begin if x > 0 then for r in select columnname from tablename loop x := x + r.columnname; end loop; end if; return x; end; $function$ set plpgsql.disable_lint to on; -- don't use a validator on this functionThis module is released under BSD license and source codes are downloadable from http://kix.fsv.cvut.cz/~stehule/download/plpgsql_lint_2011-07-15.tgz.
Instead of
ReplyDeleteplpgsql.disable_lint to on
I think enable_lint would have been a bit more easier to understand:
plpgsql.enable_lint to off
Hey Pavel, looks really useful. Would you consider releasing it on PGXN?
ReplyDelete@Gurjeet - I disagree - when somebody load a plpgsql_lint module, then he will do it with some purpose - check a functions - but it is philosophy questions - not important for this moment
ReplyDelete@ Theory
ReplyDeleteI have not a time to update source code to be correct for PGXN :(. This is main reason - and I don't know if it will work in PGXN, because it has a dependency on private PostgreSQL's library.
Is there a chance, to get this very useful module to compile against postgresql 9.1 ?
ReplyDelete@anonymous https://github.com/okbob/plpgsql_lint
ReplyDelete