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 "strings"
34 "time"
35 "unicode"
37 "github.com/sysdb/go/client"
38 "github.com/sysdb/go/proto"
39 )
41 func listAll(req request, s *Server) (*page, error) {
42 if len(req.args) != 0 {
43 return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
44 }
46 q, err := client.QueryString("LIST %s", client.Identifier(req.cmd))
47 if err != nil {
48 return nil, err
49 }
50 res, err := s.c.Query(q)
51 if err != nil {
52 return nil, err
53 }
54 // the template *must* exist
55 return tmpl(s.results[req.cmd], res)
56 }
58 func lookup(req request, s *Server) (*page, error) {
59 if req.r.Method != "POST" {
60 return nil, errors.New("Method not allowed")
61 }
62 raw, err := parseQuery(req.r.PostForm.Get("query"))
63 if err != nil {
64 return nil, err
65 }
67 var args string
68 for name, value := range raw.args {
69 if len(args) > 0 {
70 args += " AND"
71 }
73 if name == "name" {
74 args += fmt.Sprintf(" name =~ %s", value)
75 } else {
76 args += fmt.Sprintf(" %s = %s", name, value)
77 }
78 }
80 q, err := client.QueryString("LOOKUP %s MATCHING"+args, client.Identifier(raw.typ))
81 if err != nil {
82 return nil, err
83 }
84 res, err := s.c.Query(q)
85 if err != nil {
86 return nil, err
87 }
88 if t, ok := s.results[raw.typ]; ok {
89 return tmpl(t, res)
90 }
91 return nil, fmt.Errorf("Unsupported type %s", raw.typ)
92 }
94 func fetch(req request, s *Server) (*page, error) {
95 if len(req.args) == 0 {
96 return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
97 }
99 var q string
100 var err error
101 switch req.cmd {
102 case "host":
103 if len(req.args) != 1 {
104 return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
105 }
106 q, err = client.QueryString("FETCH host %s", req.args[0])
107 case "service", "metric":
108 if len(req.args) != 2 {
109 return nil, fmt.Errorf("%s not found", strings.Title(req.cmd))
110 }
111 q, err = client.QueryString("FETCH %s %s.%s", client.Identifier(req.cmd), req.args[0], req.args[1])
112 default:
113 panic("Unknown request: fetch(" + req.cmd + ")")
114 }
115 if err != nil {
116 return nil, err
117 }
119 res, err := s.c.Query(q)
120 if err != nil {
121 return nil, err
122 }
123 if req.cmd == "metric" {
124 return metric(req, res, s)
125 }
126 return tmpl(s.results[req.cmd], res)
127 }
129 var datetime = "2006-01-02 15:04:05"
131 func metric(req request, res interface{}, s *Server) (*page, error) {
132 start := time.Now().Add(-24 * time.Hour)
133 end := time.Now()
134 if req.r.Method == "POST" {
135 var err error
136 // Parse the values first to verify their format.
137 if s := req.r.PostForm.Get("start_date"); s != "" {
138 if start, err = time.Parse(datetime, s); err != nil {
139 return nil, fmt.Errorf("Invalid start time %q", s)
140 }
141 }
142 if e := req.r.PostForm.Get("end_date"); e != "" {
143 if end, err = time.Parse(datetime, e); err != nil {
144 return nil, fmt.Errorf("Invalid end time %q", e)
145 }
146 }
147 }
149 p := struct {
150 StartTime string
151 EndTime string
152 URLStart string
153 URLEnd string
154 Data interface{}
155 }{
156 start.Format(datetime),
157 end.Format(datetime),
158 start.Format(urldate),
159 end.Format(urldate),
160 res,
161 }
162 return tmpl(s.results["metric"], &p)
163 }
165 type query struct {
166 typ string
167 args map[string]string
168 }
170 func (q *query) arg(name, value string) error {
171 if _, ok := q.args[name]; ok {
172 return fmt.Errorf("Duplicate key %q", name)
173 }
174 q.args[name] = proto.EscapeString(value)
175 return nil
176 }
178 func (q *query) attr(parent, name, value string) error {
179 var k string
180 if parent != "" {
181 k = fmt.Sprintf("%s.attribute[%s]", parent, proto.EscapeString(name))
182 } else {
183 k = fmt.Sprintf("attribute[%s]", proto.EscapeString(name))
184 }
186 return q.arg(k, value)
187 }
189 func parseQuery(s string) (*query, error) {
190 tokens, err := tokenize(s)
191 if err != nil {
192 return nil, err
193 }
194 if len(tokens) == 0 {
195 return nil, errors.New("Empty query")
196 }
198 q := &query{typ: "hosts", args: make(map[string]string)}
199 for i, tok := range tokens {
200 if fields := strings.SplitN(tok, ":", 2); len(fields) == 2 {
201 // Query: [<type>:] [<sibling-type>.]<attribute>:<value> ...
202 if i == 0 && fields[1] == "" {
203 q.typ = fields[0]
204 } else if elems := strings.Split(fields[0], "."); len(elems) > 1 {
205 objs := elems[:len(elems)-1]
206 for _, o := range objs {
207 if o != "host" && o != "service" && o != "metric" {
208 return nil, fmt.Errorf("Invalid object type %q", o)
209 }
210 }
211 if err := q.attr(strings.Join(objs, "."), elems[len(elems)-1], fields[1]); err != nil {
212 return nil, err
213 }
214 } else {
215 if err := q.attr("", fields[0], fields[1]); err != nil {
216 return nil, err
217 }
218 }
219 } else {
220 if err := q.arg("name", tok); err != nil {
221 return nil, err
222 }
223 }
224 }
225 return q, nil
226 }
228 // tokenize split the string s into its tokens where a token is either a quoted
229 // string or surrounded by one or more consecutive whitespace characters.
230 func tokenize(s string) ([]string, error) {
231 scan := scanner{}
232 tokens := []string{}
233 start := -1
234 for i, r := range s {
235 if !scan.inField(r) {
236 if start == -1 {
237 // Skip leading and consecutive whitespace.
238 continue
239 }
240 tok, err := unescape(s[start:i])
241 if err != nil {
242 return nil, err
243 }
244 tokens = append(tokens, tok)
245 start = -1
246 } else if start == -1 {
247 // Found a new field.
248 start = i
249 }
250 }
251 if start >= 0 {
252 // Last (or possibly only) field.
253 tok, err := unescape(s[start:])
254 if err != nil {
255 return nil, err
256 }
257 tokens = append(tokens, tok)
258 }
260 if scan.inQuotes {
261 return nil, errors.New("quoted string not terminated")
262 }
263 if scan.escaped {
264 return nil, errors.New("illegal character escape at end of string")
265 }
266 return tokens, nil
267 }
269 func unescape(s string) (string, error) {
270 var unescaped []byte
271 var i, n int
272 for i = 0; i < len(s); i++ {
273 if s[i] != '\\' {
274 n++
275 continue
276 }
278 if i >= len(s) {
279 return "", errors.New("illegal character escape at end of string")
280 }
281 if s[i+1] != ' ' && s[i+1] != '"' && s[i+1] != '\\' {
282 // Allow simple escapes only for now.
283 return "", fmt.Errorf("illegal character escape \\%c", s[i+1])
284 }
285 if unescaped == nil {
286 unescaped = []byte(s)
287 }
288 copy(unescaped[n:], s[i+1:])
289 }
291 if unescaped != nil {
292 return string(unescaped[:n]), nil
293 }
294 return s, nil
295 }
297 type scanner struct {
298 inQuotes bool
299 escaped bool
300 }
302 func (s *scanner) inField(r rune) bool {
303 if s.escaped {
304 s.escaped = false
305 return true
306 }
307 if r == '\\' {
308 s.escaped = true
309 return true
310 }
311 if s.inQuotes {
312 if r == '"' {
313 s.inQuotes = false
314 return false
315 }
316 return true
317 }
318 if r == '"' {
319 s.inQuotes = true
320 return false
321 }
322 return !unicode.IsSpace(r)
323 }
325 // vim: set tw=78 sw=4 sw=4 noexpandtab :