![[tokkee]](http://tokkee.org/images/avatar.png){kind=avatar}
diff --git a/server/query.go b/server/query.go
--- /dev/null
+++ b/server/query.go
@@ -0,0 +1,152 @@
+//
+// Copyright (C) 2014 Sebastian 'tokkee' Harl <sh@tokkee.org>
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
+// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+// OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+// OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+// ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package server
+
+// Helper functions for handling queries.
+
+import (
+ "errors"
+ "fmt"
+ "log"
+ "strings"
+
+ "github.com/sysdb/go/proto"
+ "github.com/sysdb/go/sysdb"
+)
+
+func listAll(req request, s *Server) (*page, error) {
+ if len(req.args) != 0 {
+ return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
+ }
+
+ res, err := s.query(fmt.Sprintf("LIST %s", req.cmd))
+ if err != nil {
+ return nil, err
+ }
+ // the template *must* exist
+ return tmpl(s.results[req.cmd], res)
+}
+
+func lookup(req request, s *Server) (*page, error) {
+ if req.r.Method != "POST" {
+ return nil, errors.New("Method not allowed")
+ }
+ q := proto.EscapeString(req.r.FormValue("query"))
+ if q == "''" {
+ return nil, errors.New("Empty query")
+ }
+
+ res, err := s.query(fmt.Sprintf("LOOKUP hosts MATCHING name =~ %s", q))
+ if err != nil {
+ return nil, err
+ }
+ return tmpl(s.results["hosts"], res)
+}
+
+func fetch(req request, s *Server) (*page, error) {
+ if len(req.args) == 0 {
+ return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
+ }
+
+ var q string
+ switch req.cmd {
+ case "host":
+ if len(req.args) != 1 {
+ return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
+ }
+ q = fmt.Sprintf("FETCH host %s", proto.EscapeString(req.args[0]))
+ case "service", "metric":
+ if len(req.args) != 2 {
+ return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
+ }
+ host := proto.EscapeString(req.args[0])
+ name := proto.EscapeString(req.args[1])
+ q = fmt.Sprintf("FETCH %s %s.%s", req.cmd, host, name)
+ default:
+ panic("Unknown request: fetch(" + req.cmd + ")")
+ }
+
+ res, err := s.query(q)
+ if err != nil {
+ return nil, err
+ }
+ return tmpl(s.results[req.cmd], res)
+}
+
+func (s *Server) query(cmd string) (interface{}, error) {
+ c := <-s.conns
+ defer func() { s.conns <- c }()
+
+ m := &proto.Message{
+ Type: proto.ConnectionQuery,
+ Raw: []byte(cmd),
+ }
+ if err := c.Send(m); err != nil {
+ return nil, fmt.Errorf("Query %q: %v", cmd, err)
+ }
+
+ for {
+ m, err := c.Receive()
+ if err != nil {
+ return nil, fmt.Errorf("Failed to receive server response: %v", err)
+ }
+ if m.Type == proto.ConnectionLog {
+ log.Println(string(m.Raw[4:]))
+ continue
+ } else if m.Type == proto.ConnectionError {
+ return nil, errors.New(string(m.Raw))
+ }
+
+ t, err := m.DataType()
+ if err != nil {
+ return nil, fmt.Errorf("Failed to unmarshal response: %v", err)
+ }
+
+ var res interface{}
+ switch t {
+ case proto.HostList:
+ var hosts []sysdb.Host
+ err = proto.Unmarshal(m, &hosts)
+ res = hosts
+ case proto.Host:
+ var host sysdb.Host
+ err = proto.Unmarshal(m, &host)
+ res = host
+ case proto.Timeseries:
+ var ts sysdb.Timeseries
+ err = proto.Unmarshal(m, &ts)
+ res = ts
+ default:
+ return nil, fmt.Errorf("Unsupported data type %d", t)
+ }
+ if err != nil {
+ return nil, fmt.Errorf("Failed to unmarshal response: %v", err)
+ }
+ return res, nil
+ }
+}
+
+// vim: set tw=78 sw=4 sw=4 noexpandtab :