1 //
2 // Copyright (C) 2014 Sebastian 'tokkee' Harl <sh@tokkee.org>
3 // All rights reserved.
4 //
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions
7 // are met:
8 // 1. Redistributions of source code must retain the above copyright
9 // notice, this list of conditions and the following disclaimer.
10 // 2. Redistributions in binary form must reproduce the above copyright
11 // notice, this list of conditions and the following disclaimer in the
12 // documentation and/or other materials provided with the distribution.
13 //
14 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15 // ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
16 // TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17 // PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
18 // CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 // EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
21 // OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
22 // WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
23 // OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
24 // ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 package server
28 // Helper functions for handling queries.
30 import (
31 "errors"
32 "fmt"
33 "log"
34 "strings"
35 "time"
36 "unicode"
38 "github.com/sysdb/go/proto"
39 "github.com/sysdb/go/sysdb"
40 )
42 func listAll(req request, s *Server) (*page, error) {
43 if len(req.args) != 0 {
44 return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
45 }
47 res, err := s.query("LIST %s", identifier(req.cmd))
48 if err != nil {
49 return nil, err
50 }
51 // the template *must* exist
52 return tmpl(s.results[req.cmd], res)
53 }
55 func lookup(req request, s *Server) (*page, error) {
56 if req.r.Method != "POST" {
57 return nil, errors.New("Method not allowed")
58 }
59 tokens, err := tokenize(req.r.PostForm.Get("query"))
60 if err != nil {
61 return nil, err
62 }
63 if len(tokens) == 0 {
64 return nil, errors.New("Empty query")
65 }
67 var args string
68 for i, tok := range tokens {
69 if i != 0 {
70 args += " AND"
71 }
73 if fields := strings.SplitN(tok, ":", 2); len(fields) == 2 {
74 args += fmt.Sprintf(" attribute[%s] = %s",
75 proto.EscapeString(fields[0]), proto.EscapeString(fields[1]))
76 } else {
77 args += fmt.Sprintf(" name =~ %s", proto.EscapeString(tok))
78 }
79 }
81 res, err := s.query("LOOKUP hosts MATCHING" + args)
82 if err != nil {
83 return nil, err
84 }
85 return tmpl(s.results["hosts"], res)
86 }
88 func fetch(req request, s *Server) (*page, error) {
89 if len(req.args) == 0 {
90 return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
91 }
93 var res interface{}
94 var err error
95 switch req.cmd {
96 case "host":
97 if len(req.args) != 1 {
98 return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
99 }
100 res, err = s.query("FETCH host %s", req.args[0])
101 case "service", "metric":
102 if len(req.args) != 2 {
103 return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
104 }
105 res, err = s.query("FETCH %s %s.%s", identifier(req.cmd), req.args[0], req.args[1])
106 if req.cmd == "metric" {
107 return metric(req, res, s)
108 }
109 default:
110 panic("Unknown request: fetch(" + req.cmd + ")")
111 }
112 if err != nil {
113 return nil, err
114 }
115 return tmpl(s.results[req.cmd], res)
116 }
118 var datetime = "2006-01-02 15:04:05"
120 func metric(req request, res interface{}, s *Server) (*page, error) {
121 start := time.Now().Add(-24 * time.Hour)
122 end := time.Now()
123 if req.r.Method == "POST" {
124 var err error
125 // Parse the values first to verify their format.
126 if s := req.r.PostForm.Get("start_date"); s != "" {
127 if start, err = time.Parse(datetime, s); err != nil {
128 return nil, fmt.Errorf("Invalid start time %q", s)
129 }
130 }
131 if e := req.r.PostForm.Get("end_date"); e != "" {
132 if end, err = time.Parse(datetime, e); err != nil {
133 return nil, fmt.Errorf("Invalid end time %q", e)
134 }
135 }
136 }
138 p := struct {
139 StartTime string
140 EndTime string
141 URLStart string
142 URLEnd string
143 Data interface{}
144 }{
145 start.Format(datetime),
146 end.Format(datetime),
147 start.Format(urldate),
148 end.Format(urldate),
149 res,
150 }
151 return tmpl(s.results["metric"], &p)
152 }
154 // tokenize split the string s into its tokens where a token is either a quoted
155 // string or surrounded by one or more consecutive whitespace characters.
156 func tokenize(s string) ([]string, error) {
157 scan := scanner{}
158 tokens := []string{}
159 start := -1
160 for i, r := range s {
161 if !scan.inField(r) {
162 if start == -1 {
163 // Skip leading and consecutive whitespace.
164 continue
165 }
166 tok, err := unescape(s[start:i])
167 if err != nil {
168 return nil, err
169 }
170 tokens = append(tokens, tok)
171 start = -1
172 } else if start == -1 {
173 // Found a new field.
174 start = i
175 }
176 }
177 if start >= 0 {
178 // Last (or possibly only) field.
179 tok, err := unescape(s[start:])
180 if err != nil {
181 return nil, err
182 }
183 tokens = append(tokens, tok)
184 }
186 if scan.inQuotes {
187 return nil, errors.New("quoted string not terminated")
188 }
189 if scan.escaped {
190 return nil, errors.New("illegal character escape at end of string")
191 }
192 return tokens, nil
193 }
195 func unescape(s string) (string, error) {
196 var unescaped []byte
197 var i, n int
198 for i = 0; i < len(s); i++ {
199 if s[i] != '\\' {
200 n++
201 continue
202 }
204 if i >= len(s) {
205 return "", errors.New("illegal character escape at end of string")
206 }
207 if s[i+1] != ' ' && s[i+1] != '"' && s[i+1] != '\\' {
208 // Allow simple escapes only for now.
209 return "", fmt.Errorf("illegal character escape \\%c", s[i+1])
210 }
211 if unescaped == nil {
212 unescaped = []byte(s)
213 }
214 copy(unescaped[n:], s[i+1:])
215 }
217 if unescaped != nil {
218 return string(unescaped[:n]), nil
219 }
220 return s, nil
221 }
223 type scanner struct {
224 inQuotes bool
225 escaped bool
226 }
228 func (s *scanner) inField(r rune) bool {
229 if s.escaped {
230 s.escaped = false
231 return true
232 }
233 if r == '\\' {
234 s.escaped = true
235 return true
236 }
237 if s.inQuotes {
238 if r == '"' {
239 s.inQuotes = false
240 return false
241 }
242 return true
243 }
244 if r == '"' {
245 s.inQuotes = true
246 return false
247 }
248 return !unicode.IsSpace(r)
249 }
251 type identifier string
253 func (s *Server) query(cmd string, args ...interface{}) (interface{}, error) {
254 c := <-s.conns
255 defer func() { s.conns <- c }()
257 for i, arg := range args {
258 switch v := arg.(type) {
259 case identifier:
260 // Nothing to do.
261 case string:
262 args[i] = proto.EscapeString(v)
263 case time.Time:
264 args[i] = v.Format(datetime)
265 default:
266 panic(fmt.Sprintf("query: invalid type %T", arg))
267 }
268 }
270 cmd = fmt.Sprintf(cmd, args...)
271 m := &proto.Message{
272 Type: proto.ConnectionQuery,
273 Raw: []byte(cmd),
274 }
275 if err := c.Send(m); err != nil {
276 return nil, fmt.Errorf("Query %q: %v", cmd, err)
277 }
279 for {
280 m, err := c.Receive()
281 if err != nil {
282 return nil, fmt.Errorf("Failed to receive server response: %v", err)
283 }
284 if m.Type == proto.ConnectionLog {
285 log.Println(string(m.Raw[4:]))
286 continue
287 } else if m.Type == proto.ConnectionError {
288 return nil, errors.New(string(m.Raw))
289 }
291 t, err := m.DataType()
292 if err != nil {
293 return nil, fmt.Errorf("Failed to unmarshal response: %v", err)
294 }
296 var res interface{}
297 switch t {
298 case proto.HostList:
299 var hosts []sysdb.Host
300 err = proto.Unmarshal(m, &hosts)
301 res = hosts
302 case proto.Host:
303 var host sysdb.Host
304 err = proto.Unmarshal(m, &host)
305 res = host
306 case proto.Timeseries:
307 var ts sysdb.Timeseries
308 err = proto.Unmarshal(m, &ts)
309 res = ts
310 default:
311 return nil, fmt.Errorf("Unsupported data type %d", t)
312 }
313 if err != nil {
314 return nil, fmt.Errorf("Failed to unmarshal response: %v", err)
315 }
316 return res, nil
317 }
318 }
320 // vim: set tw=78 sw=4 sw=4 noexpandtab :