github.com/alibaba/ilogtail/pkg@v0.0.0-20250526110833-c53b480d046c/fmtstr/format_index.go (about)

     1  // Copyright 2023 iLogtail Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package fmtstr
    16  
    17  import "time"
    18  
    19  // FormatIndex name Elasticsearch index base on time like Logstash and Beats
    20  func FormatIndex(targetValues map[string]string, indexPattern string, indexTimestamp uint32) (*string, error) {
    21  	sf, err := Compile(indexPattern, func(key string, ops []VariableOp) (FormatEvaler, error) {
    22  		// with timestamp expression, like %{+yyyyMM}
    23  		if key[0] == '+' {
    24  			indexTime := time.Unix(int64(indexTimestamp), 0)
    25  			index := FormatTimestamp(&indexTime, key[1:])
    26  			return StringElement{S: index}, nil
    27  		}
    28  		if value, ok := targetValues[key]; ok {
    29  			return StringElement{S: value}, nil
    30  		}
    31  		return StringElement{S: key}, nil
    32  	})
    33  	if err != nil {
    34  		return nil, err
    35  	}
    36  	topic, err := sf.Run(nil)
    37  	if err != nil {
    38  		return nil, err
    39  	}
    40  	return &topic, nil
    41  }