| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| package common |
| |
| import ( |
| "encoding/json" |
| ) |
| |
| // |
| // Represents queries that can be sent to htraced. |
| // |
| // Each query consists of set of predicates that will be 'AND'ed together to |
| // return a set of spans. Predicates contain an operation, a field, and a |
| // value. |
| // |
| // For example, a query might be "return the first 100 spans between 5:00pm |
| // and 5:01pm" This query would have two predicates: time greater than or |
| // equal to 5:00pm, and time less than or equal to 5:01pm. |
| // In HTrace, times are always expressed in milliseconds since the Epoch. |
| // So this would become: |
| // { "lim" : 100, "pred" : [ |
| // { "op" : "ge", "field" : "begin", "val" : 1234 }, |
| // { "op" : "le", "field" : "begin", "val" : 5678 }, |
| // ] } |
| // |
| // Where '1234' and '5678' were replaced by times since the epoch in |
| // milliseconds. |
| // |
| |
| type Op string |
| |
| const ( |
| CONTAINS Op = "cn" |
| EQUALS Op = "eq" |
| LESS_THAN_OR_EQUALS Op = "le" |
| GREATER_THAN_OR_EQUALS Op = "ge" |
| GREATER_THAN Op = "gt" |
| ) |
| |
| func (op Op) IsDescending() bool { |
| return op == LESS_THAN_OR_EQUALS |
| } |
| |
| func (op Op) IsValid() bool { |
| ops := ValidOps() |
| for i := range ops { |
| if ops[i] == op { |
| return true |
| } |
| } |
| return false |
| } |
| |
| func ValidOps() []Op { |
| return []Op{CONTAINS, EQUALS, LESS_THAN_OR_EQUALS, GREATER_THAN_OR_EQUALS, |
| GREATER_THAN} |
| } |
| |
| type Field string |
| |
| const ( |
| SPAN_ID Field = "spanid" |
| DESCRIPTION Field = "description" |
| BEGIN_TIME Field = "begin" |
| END_TIME Field = "end" |
| DURATION Field = "duration" |
| TRACER_ID Field = "tracerid" |
| ) |
| |
| func (field Field) IsValid() bool { |
| fields := ValidFields() |
| for i := range fields { |
| if fields[i] == field { |
| return true |
| } |
| } |
| return false |
| } |
| |
| func ValidFields() []Field { |
| return []Field{SPAN_ID, DESCRIPTION, BEGIN_TIME, END_TIME, |
| DURATION, TRACER_ID} |
| } |
| |
| type Predicate struct { |
| Op Op `json:"op"` |
| Field Field `json:"field"` |
| Val string `val:"val"` |
| } |
| |
| func (pred *Predicate) String() string { |
| buf, err := json.Marshal(pred) |
| if err != nil { |
| panic(err) |
| } |
| return string(buf) |
| } |
| |
| type Query struct { |
| Predicates []Predicate `json:"pred"` |
| Lim int `json:"lim"` |
| Prev *Span `json:"prev"` |
| } |
| |
| func (query *Query) String() string { |
| buf, err := json.Marshal(query) |
| if err != nil { |
| panic(err) |
| } |
| return string(buf) |
| } |