goext/mongo/internal/string_util.go

46 lines
1.5 KiB
Go

// Copyright (C) MongoDB, Inc. 2017-present.
//
// Licensed 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
package internal
import (
"fmt"
"go.mongodb.org/mongo-driver/bson"
)
// StringSliceFromRawElement decodes the provided BSON element into a []string. This internally calls
// StringSliceFromRawValue on the element's value. The error conditions outlined in that function's documentation
// apply for this function as well.
func StringSliceFromRawElement(element bson.RawElement) ([]string, error) {
return StringSliceFromRawValue(element.Key(), element.Value())
}
// StringSliceFromRawValue decodes the provided BSON value into a []string. This function returns an error if the value
// is not an array or any of the elements in the array are not strings. The name parameter is used to add context to
// error messages.
func StringSliceFromRawValue(name string, val bson.RawValue) ([]string, error) {
arr, ok := val.ArrayOK()
if !ok {
return nil, fmt.Errorf("expected '%s' to be an array but it's a BSON %s", name, val.Type)
}
arrayValues, err := arr.Values()
if err != nil {
return nil, err
}
strs := make([]string, 0, len(arrayValues))
for _, arrayVal := range arrayValues {
str, ok := arrayVal.StringValueOK()
if !ok {
return nil, fmt.Errorf("expected '%s' to be an array of strings, but found a BSON %s", name, arrayVal.Type)
}
strs = append(strs, str)
}
return strs, nil
}