github.com/go-kivik/kivik/v4@v4.3.2/x/server/config/config.go (about)

     1  // Licensed under the Apache License, Version 2.0 (the "License"); you may not
     2  // use this file except in compliance with the License. You may obtain a copy of
     3  // the License at
     4  //
     5  //  http://www.apache.org/licenses/LICENSE-2.0
     6  //
     7  // Unless required by applicable law or agreed to in writing, software
     8  // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
     9  // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
    10  // License for the specific language governing permissions and limitations under
    11  // the License.
    12  
    13  // Package config manages server configuration.
    14  package config
    15  
    16  import (
    17  	"context"
    18  	"net/http"
    19  
    20  	internal "github.com/go-kivik/kivik/v4/int/errors"
    21  )
    22  
    23  // Config provides access to read server configuration. Configuration
    24  // backends that allow modifying configuration will also implement
    25  // [ConfigWriter].
    26  type Config interface {
    27  	All(context.Context) (map[string]map[string]string, error)
    28  	Section(context.Context, string) (map[string]string, error)
    29  	Key(context.Context, string, string) (string, error)
    30  	Reload(context.Context) error
    31  }
    32  
    33  // Writer allows setting server configuration.
    34  type Writer interface {
    35  	// SetKey sets a new config value, and returns the old value.
    36  	SetKey(context.Context, string, string, string) (string, error)
    37  	Delete(context.Context, string, string) (string, error)
    38  }
    39  
    40  type defaultConfig struct {
    41  	conf map[string]map[string]string
    42  }
    43  
    44  var (
    45  	_ Config = (*defaultConfig)(nil)
    46  	_ Writer = (*defaultConfig)(nil)
    47  )
    48  
    49  // Default returns a Config implementation which returns default values for all
    50  // configuration options, and preserves changed settings only until restart.
    51  func Default() Config {
    52  	return &defaultConfig{
    53  		conf: map[string]map[string]string{
    54  			"couchdb": {
    55  				"users_db_suffix": "_users",
    56  			},
    57  		},
    58  	}
    59  }
    60  
    61  // Map returns a Config implementation which returns the provided configuration.
    62  func Map(conf map[string]map[string]string) Config {
    63  	return &defaultConfig{conf: conf}
    64  }
    65  
    66  func (c *defaultConfig) All(context.Context) (map[string]map[string]string, error) {
    67  	return c.conf, nil
    68  }
    69  
    70  func (c *defaultConfig) Section(_ context.Context, section string) (map[string]string, error) {
    71  	return c.conf[section], nil
    72  }
    73  
    74  func (c *defaultConfig) Key(_ context.Context, section, key string) (string, error) {
    75  	if v, ok := c.conf[section][key]; ok {
    76  		return v, nil
    77  	}
    78  	return "", &internal.Error{Status: http.StatusNotFound, Message: "unknown_config_value"}
    79  }
    80  
    81  func (c *defaultConfig) Reload(context.Context) error {
    82  	return nil
    83  }
    84  
    85  func (c *defaultConfig) SetKey(_ context.Context, section, key string, value string) (string, error) {
    86  	s, ok := c.conf[section]
    87  	if !ok {
    88  		s = map[string]string{}
    89  		c.conf[section] = s
    90  	}
    91  	old := s[key]
    92  	s[key] = value
    93  	return old, nil
    94  }
    95  
    96  func (c *defaultConfig) Delete(_ context.Context, section, key string) (string, error) {
    97  	if v, ok := c.conf[section][key]; ok {
    98  		delete(c.conf[section], key)
    99  		return v, nil
   100  	}
   101  	return "", &internal.Error{Status: http.StatusNotFound, Message: "unknown_config_value"}
   102  }