postgres SQL query throws error in node JS

Question

I set up an API where on client side user can calculate a route between to points. However, I have trouble with the psql query, which works in postgres but when I use the same query in node JS I got an error.

I am using nodeJS, Express and Postgres. If I run the query below in pgAdmin4, I get the expected output.

SELECT b.gid, b.the_geom, b.cost_s, b.length_m FROM pgr_dijkstra('SELECT gid::bigint as id, source::bigint, 
                                           target::bigint, cost_s::double precision as cost, 
                                           reverse_cost_s::double precision as reverse_cost FROM ways 
                                           WHERE the_geom && ST_Expand((SELECT ST_Collect(the_geom) 
                                           FROM ways_vertices_pgr WHERE id IN(589143, 581050)), 0.01)', 
589143, 581050) a LEFT JOIN ways b ON (a.edge = b.gid);

But when I use the same query in Node Js (see below), I get an error message saying error: syntax error at or near "&&" . What am I doing wrong?

const start = parseInt(request.params.start)
const end = parseInt(request.params.end)

const sql2 = 
     "SELECT b.gid, b.the_geom, b.cost_s, b.length_m FROM pgr_dijkstra('SELECT gid::bigint as id, source::bigint,"+
     "target::bigint, cost_s::double precision as cost," +
     "reverse_cost_s::double precision as reverse_cost FROM ways" + 
     "WHERE the_geom && ST_Expand((SELECT ST_Collect(the_geom)" + 
     "FROM ways_vertices_pgr WHERE id IN(" + start + "," + end + ")), 0.01)'," +
      start + "," + end + ") a LEFT JOIN ways b ON (a.edge = b.gid);"

Answer 1

Got the answer. Instead of start and end I used arguments using the syntax $1 ...and added the data type of the arguments. In my case ineteger

SELECT b.gid, b.the_geom, b.cost_s, b.length_m FROM pgr_dijkstra('SELECT gid::bigint as id, source::bigint, 
                                           target::bigint, cost_s::double precision as cost, 
                                           reverse_cost_s::double precision as reverse_cost FROM ways 
                                           WHERE the_geom && ST_Expand((SELECT ST_Collect(the_geom) 
                                           FROM ways_vertices_pgr WHERE id IN(' || $1::integer || ',' || $2::integer ||')), 0.01)', 
    $1::integer, $2::integer) a LEFT JOIN ways b ON (a.edge = b.gid);