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10.6. Ad-Hoc REST Services

Apart from the explicitly defined procedure based rest services, the generated jax-rs war file will also implicitly include a special rest based service under URI "/query" that can take any XML or JSON producing SQL as parameter and expose the results of that query as result of the service. This service is defined with "POST", accepting a Form Parameter named "sql". For example, after you deploy the VDB defined in above example, you can issue a HTTP POST call as 
    http://localhost:8080/sample_1/view/query
    sql=SELECT XMLELEMENT(NAME "rows",XMLAGG(XMLELEMENT(NAME "row", XMLFOREST(e1, e2)))) AS xml_out FROM PM1.G1
A sample HTTP Request from Java can be made like below: 

        public static String httpCall(String url, String method, String params) throws Exception {
                StringBuffer buff = new StringBuffer();
                HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection();
                connection.setRequestMethod(method);
                connection.setDoOutput(true);

                if (method.equalsIgnoreCase("post")) {
                        OutputStreamWriter wr = new OutputStreamWriter(connection.getOutputStream());
                    wr.write(params);
                    wr.flush();
                }

                BufferedReader serverResponse = new BufferedReader(new InputStreamReader(connection.getInputStream()));
                String line;
                while ((line = serverResponse.readLine()) != null) {
                        buff.append(line);
                }
                return buff.toString();
        }

        public static void main(String[] args) throws Exception {
            String params = URLEncoder.encode("sql", "UTF-8") + "=" + URLEncoder.encode("SELECT XMLELEMENT(NAME "rows",XMLAGG(XMLELEMENT(NAME "row", XMLFOREST(e1, e2)))) AS xml_out FROM PM1.G1", "UTF-8");
            httpCall("http://localhost:8080/sample_1/view/query", "POST", params);
        }