cuelang.org/go@v0.10.1/pkg/encoding/csv/manual.go (about)

     1  // Copyright 2018 The CUE 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 csv
    16  
    17  import (
    18  	"encoding/csv"
    19  	"io"
    20  	"strings"
    21  
    22  	"cuelang.org/go/cue"
    23  )
    24  
    25  // Encode encode the given list of lists to CSV.
    26  func Encode(x cue.Value) (string, error) {
    27  	var b strings.Builder
    28  	w := csv.NewWriter(&b)
    29  	iter, err := x.List()
    30  	if err != nil {
    31  		return "", err
    32  	}
    33  	for iter.Next() {
    34  		row, err := iter.Value().List()
    35  		if err != nil {
    36  			return "", err
    37  		}
    38  		a := []string{}
    39  		for row.Next() {
    40  			col := row.Value()
    41  			if str, err := col.String(); err == nil {
    42  				a = append(a, str)
    43  			} else {
    44  				b, err := col.MarshalJSON()
    45  				if err != nil {
    46  					return "", err
    47  				}
    48  				a = append(a, string(b))
    49  			}
    50  		}
    51  		_ = w.Write(a)
    52  	}
    53  	w.Flush()
    54  	return b.String(), nil
    55  }
    56  
    57  // Decode reads in a csv into a list of lists.
    58  func Decode(r io.Reader) ([][]string, error) {
    59  	return csv.NewReader(r).ReadAll()
    60  }