examples_test.go

Documentation: cuelang.org/go/cuego

     1  // Copyright 2019 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 cuego_test
    16  
    17  import (
    18  	"fmt"
    19  	"strings"
    20  
    21  	"cuelang.org/go/cue/errors"
    22  	"cuelang.org/go/cuego"
    23  )
    24  
    25  func ExampleComplete_structTag() {
    26  	type Sum struct {
    27  		A int `cue:"C-B" json:",omitempty"`
    28  		B int `cue:"C-A" json:",omitempty"`
    29  		C int `cue:"A+B" json:",omitempty"`
    30  	}
    31  
    32  	a := Sum{A: 1, B: 5}
    33  	err := cuego.Complete(&a)
    34  	fmt.Printf("completed: %#v (err: %v)\n", a, err)
    35  
    36  	a = Sum{A: 2, C: 8}
    37  	err = cuego.Complete(&a)
    38  	fmt.Printf("completed: %#v (err: %v)\n", a, err)
    39  
    40  	a = Sum{A: 2, B: 3, C: 8}
    41  	err = cuego.Complete(&a)
    42  	fmt.Println(errMsg(err))
    43  
    44  	//Output:
    45  	// completed: cuego_test.Sum{A:1, B:5, C:6} (err: <nil>)
    46  	// completed: cuego_test.Sum{A:2, B:6, C:8} (err: <nil>)
    47  	// 2 errors in empty disjunction:
    48  	// conflicting values null and {A:2,B:3,C:8} (mismatched types null and struct)
    49  	// A: conflicting values 5 and 2
    50  }
    51  
    52  func ExampleConstrain() {
    53  	type Config struct {
    54  		Filename string
    55  		OptFile  string `json:",omitempty"`
    56  		MaxCount int
    57  		MinCount int
    58  
    59  		// TODO: show a field with time.Time
    60  	}
    61  
    62  	err := cuego.Constrain(&Config{}, `{
    63  		let jsonFile = =~".json$"
    64  
    65  		// Filename must be defined and have a .json extension
    66  		Filename: jsonFile
    67  
    68  		// OptFile must be undefined or be a file name with a .json extension
    69  		OptFile?: jsonFile
    70  
    71  		MinCount: >0 & <=MaxCount
    72  		MaxCount: <=10_000
    73  	}`)
    74  
    75  	fmt.Println("error:", errMsg(err))
    76  
    77  	fmt.Println("validate:", errMsg(cuego.Validate(&Config{
    78  		Filename: "foo.json",
    79  		MaxCount: 1200,
    80  		MinCount: 39,
    81  	})))
    82  
    83  	fmt.Println("validate:", errMsg(cuego.Validate(&Config{
    84  		Filename: "foo.json",
    85  		MaxCount: 12,
    86  		MinCount: 39,
    87  	})))
    88  
    89  	fmt.Println("validate:", errMsg(cuego.Validate(&Config{
    90  		Filename: "foo.jso",
    91  		MaxCount: 120,
    92  		MinCount: 39,
    93  	})))
    94  
    95  	// TODO(errors): fix bound message (should be "does not match")
    96  
    97  	//Output:
    98  	// error: nil
    99  	// validate: nil
   100  	// validate: 2 errors in empty disjunction:
   101  	// conflicting values null and {Filename:"foo.json",MaxCount:12,MinCount:39} (mismatched types null and struct)
   102  	// MinCount: invalid value 39 (out of bound <=12)
   103  	// validate: 2 errors in empty disjunction:
   104  	// conflicting values null and {Filename:"foo.jso",MaxCount:120,MinCount:39} (mismatched types null and struct)
   105  	// Filename: invalid value "foo.jso" (out of bound =~".json$")
   106  }
   107  
   108  func errMsg(err error) string {
   109  	a := []string{}
   110  	for _, err := range errors.Errors(err) {
   111  		a = append(a, err.Error())
   112  	}
   113  	s := strings.Join(a, "\n")
   114  	if s == "" {
   115  		return "nil"
   116  	}
   117  	return s
   118  }
   119
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