JsonConfigReader

Config reader that reads a configuration from a JSON file.

Implements: FileConfigReader

Description

The JsonConfigReader class allows you to create a config reader that reads a configuration from a JSON file.

Important points

  • The reader supports parameterization using Handlebar template engine.

Configuration parameters

  • path: path to the configuration file
  • parameters: this entire section is used as template parameters
  • …

Constructors

NewJsonConfigReader

Creates a new instance of the config reader.

NewJsonConfigReader(path string) *JsonConfigReader

  • path: string - (optional) path to the configuration file.

NewEmptyJsonConfigReader

Creates a new instance of the config reader.

NewEmptyJsonConfigReader() *JsonConfigReader

Methods

ReadConfig

Reads a configuration and parameterizes it with given values.

(c *JsonConfigReader) ReadConfig(ctx context.Context, context.Context, correlationId string, parameters *cconfig.ConfigParams) (result *cconfig.ConfigParams, err error)

  • ctx: context.Context - operation context.
  • correlationId: string - (optional) transaction id used to trace execution through the call chain.
  • parameters: *cconfig.ConfigParams - values to parameters the configuration or nil to skip parameterization.
  • returns: (result *cconfig.ConfigParams, err error) - ConfigParams configuration.

ReadObject

Reads a configuration file, parameterizes its content and converts it into JSON object.

(c *JsonConfigReader) ReadObject(ctx context.Context, correlationId string, parameters *cconfig.ConfigParams) (any, error)

  • ctx: context.Context - operation context.
  • correlationId: string - (optional) transaction id used to trace execution through the call chain.
  • parameters: *cconfig.ConfigParams - values of the configuration parameters.
  • returns: (any, error) - JSON object with configuration.

ReadConfig

Reads a configuration from a file, parameterizes it with given values and returns a new ConfigParams object.

(c *JsonConfigReader) ReadConfig(ctx context.Context, correlationId string, parameters *cconfig.ConfigParams) (result *cconfig.ConfigParams, err error)

  • ctx: context.Context - operation context.
  • correlationId: string - (optional) transaction id used to trace execution through the call chain.
  • path: string - path to a configuration file.
  • parameters: *cconfig.ConfigParams - values of the configuration parameters.
  • returns: (result *cconfig.ConfigParams, err error) - ConfigParams configuration.

ReadJsonObject

Reads a configuration file, parameterizes its content and converts it into a JSON object.

ReadJsonObject(ctx context.Context, correlationId string, path string, parameters *cconfig.ConfigParams) (any, error)

  • ctx: context.Context - operation context.
  • correlationId: string - (optional) transaction id used to trace execution through the call chain.
  • path: string - path to configuration file.
  • parameters: *cconfig.ConfigParams - values of the configuration parameters.
  • returns: (any, error) - JSON object with configuration.

Examples

{ "key1": "{{KEY1_VALUE}}", "key2": "{{KEY2_VALUE}}" }

configReader := NewJsonConfigReader("config.json")
parameters := NewConfigParamsFromTuples("KEY1_VALUE", 123, "KEY2_VALUE", "ABC")
res, err := configReader.ReadConfig(context.Background(), "123", parameters)

See also