-
Notifications
You must be signed in to change notification settings - Fork 0
/
engine.go
190 lines (159 loc) · 4.6 KB
/
engine.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
package engine
import (
"errors"
"fmt"
"github.com/margostino/babeldb/collector"
"github.com/margostino/babeldb/common"
"github.com/margostino/babeldb/model"
"github.com/margostino/babeldb/storage"
"github.com/robfig/cron/v3"
"github.com/xwb1989/sqlparser"
"github.com/xwb1989/sqlparser/dependency/querypb"
"strings"
)
const UrlSeparator = "@@@"
type Engine struct {
storage *storage.Storage
jobs []*cron.Cron
}
func New() *Engine {
return &Engine{
storage: storage.New(),
jobs: make([]*cron.Cron, 0),
}
}
func (e *Engine) createSource(source *model.Source, schedule string) {
job := cron.New(cron.WithSeconds())
collector := collector.New(source)
e.jobs = append(e.jobs, job)
e.storage.AddSource(source)
collector.Collect()
job.AddFunc(schedule, collector.Collect)
job.Start()
}
func (e *Engine) Parse(input string) (*model.Query, error) {
var queryInput string
var query = model.NewQuery()
var bindVars = make(map[string]*querypb.BindVariable)
var params = make(map[string]*model.ExpressionNode, 0)
if strings.ToLower(input) == "show sources" {
query.Source = model.Wildcard
query.QueryType = model.ShowSources
return query, nil
}
if shouldCreateSource(input) {
parts := common.NewString(input).
ReplaceAll("'", "").
TrimSpace().
Split(" ").
Values()
name := parts[2]
url := parts[4]
schedule := fmt.Sprintf("%s %s %s %s %s", parts[6], parts[7], parts[8], parts[9], parts[10])
queryInput = fmt.Sprintf("insert into %s (url, schedule) values ('%s', '%s')", name, url, schedule)
} else {
queryInput = input
}
statement, err := sqlparser.Parse(queryInput)
sqlparser.Normalize(statement, bindVars, "")
if !common.IsError(err, "when parsing SQL input") {
switch stmt := statement.(type) {
case *sqlparser.Select:
var whereClauses string
whereBuffer := sqlparser.NewTrackedBuffer(nil)
sourceBuffer := sqlparser.NewTrackedBuffer(nil)
selectBuffer := sqlparser.NewTrackedBuffer(nil)
stmt.SelectExprs.Format(selectBuffer)
stmt.From.Format(sourceBuffer)
if stmt.Where != nil && stmt.Where.Expr != nil {
stmt.Where.Expr.Format(whereBuffer)
whereClauses = whereBuffer.String()
}
fields := common.NewString(selectBuffer.String()).
ReplaceAll(" ", "").
ReplaceAll("`", "").
Split(",").
Values()
// TODO: improve and move validations
for _, field := range fields {
if !model.Fields.Contains(field) {
return nil, errors.New("invalid fields")
}
}
//conditions := strings.Split(whereBuffer.String(), " and ")
var tokens []string
if whereClauses != "" {
tokens = common.NewString(whereClauses).
ReplaceAll("not like", "not_like").
ReplaceAll("`", "").
Split(" ").
Values()
}
var expression = &model.ExpressionTree{
Root: nil,
}
for _, value := range tokens {
token := strings.Split(value, " ")[0]
expression.Insert(token)
if len(token) == 2 && token[0:1] == ":" {
params[token[1:]] = expression.GetParamNode(expression.Root)
}
}
for key, bindVar := range bindVars {
params[key].Key.Value = string(bindVar.Value)
if bindVar.Type == querypb.Type_VARBINARY {
params[key].Key.Type = model.StringType
}
}
query.Source = sourceBuffer.String()
query.QueryType = model.SelectType
query.Fields = common.NewStringSlice(fields...)
query.Distinct = strings.HasPrefix(queryInput, "select distinct")
query.Expression = expression
case *sqlparser.Insert:
tableBuffer := sqlparser.NewTrackedBuffer(nil)
stmt.Table.Format(tableBuffer)
if len(bindVars) == 2 {
query.Source = tableBuffer.String()
query.QueryType = model.CreateType
query.Url = string(bindVars["1"].Value)
query.Schedule = string(bindVars["2"].Value)
} else {
err = errors.New("wrong query variables size")
}
}
}
//if query.QueryType == model.SelectType {
// query.InOrderPrint()
//}
return query, err
}
func (e *Engine) Solve(query *model.Query) *model.QueryResults {
var results = &model.QueryResults{
Sources: make([]*model.Source, 0),
Page: model.NewPage(),
}
sourceName := query.Source
switch query.QueryType {
case model.SelectType:
meta, sections := e.storage.Select(sourceName, query)
results.Page = &model.Page{
Meta: meta,
Sections: sections,
}
case model.ShowSources:
sources := e.storage.Show()
results.Sources = sources
case model.CreateType:
url := query.Url
schedule := query.Schedule
source := &model.Source{
Name: sourceName,
Url: url,
Page: model.NewPage(),
}
results.Sources = append(results.Sources, source)
go e.createSource(source, schedule)
}
return results
}