go.chromium.org/luci@v0.0.0-20240309015107-7cdc2e660f33/scheduler/appengine/task/utils/kvlist.go (about)

     1  // Copyright 2015 The LUCI 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 utils
    16  
    17  import (
    18  	"fmt"
    19  	"sort"
    20  	"strings"
    21  )
    22  
    23  // KV is key and value strings.
    24  type KV struct {
    25  	Key   string
    26  	Value string
    27  }
    28  
    29  // KVList if list of KV pairs.
    30  type KVList []KV
    31  
    32  // ValidateKVList makes sure each string in the list is valid key-value pair.
    33  func ValidateKVList(kind string, list []string, sep rune) error {
    34  	for _, item := range list {
    35  		if !strings.ContainsRune(item, sep) {
    36  			return fmt.Errorf("bad %s, not a 'key%svalue' pair: %q", kind, string(sep), item)
    37  		}
    38  	}
    39  	return nil
    40  }
    41  
    42  // KVListFromMap converts a map to KVList.
    43  func KVListFromMap(m map[string]string) KVList {
    44  	keys := make([]string, 0, len(m))
    45  	for k := range m {
    46  		keys = append(keys, k)
    47  	}
    48  	sort.Strings(keys)
    49  	kvList := make([]KV, len(keys))
    50  	for i, k := range keys {
    51  		kvList[i] = KV{
    52  			Key:   k,
    53  			Value: m[k],
    54  		}
    55  	}
    56  	return kvList
    57  }
    58  
    59  // UnpackKVList takes validated list of k-v pair strings and returns list of
    60  // structs.
    61  //
    62  // Silently skips malformed strings. Use ValidateKVList to detect them before
    63  // calling this function.
    64  func UnpackKVList(list []string, sep rune) (out KVList) {
    65  	for _, item := range list {
    66  		idx := strings.IndexRune(item, sep)
    67  		if idx == -1 {
    68  			continue
    69  		}
    70  		out = append(out, KV{
    71  			Key:   item[:idx],
    72  			Value: item[idx+1:],
    73  		})
    74  	}
    75  	return out
    76  }
    77  
    78  // Pack converts KV list to a list of strings.
    79  func (l KVList) Pack(sep rune) []string {
    80  	out := make([]string, len(l))
    81  	for i, kv := range l {
    82  		out[i] = kv.Key + string(sep) + kv.Value
    83  	}
    84  	return out
    85  }