Class: LaunchDarkly::FileDataSource
- Inherits:
-
Object
- Object
- LaunchDarkly::FileDataSource
- Defined in:
- lib/ldclient-rb/file_data_source.rb
Overview
Provides a way to use local files as a source of feature flag state. This would typically be used in a test environment, to operate using a predetermined feature flag state without an actual LaunchDarkly connection.
To use this component, call FileDataSource.factory, and store its return value in the
Config#data_source property of your LaunchDarkly client configuration. In the options
to factory
, set paths
to the file path(s) of your data file(s):
file_source = FileDataSource.factory(paths: [ myFilePath ])
config = LaunchDarkly::Config.new(data_source: file_source)
This will cause the client not to connect to LaunchDarkly to get feature flags. The client may still make network connections to send analytics events, unless you have disabled this with Config#send_events or Config#offline?.
Flag data files can be either JSON or YAML. They contain an object with three possible properties:
flags
: Feature flag definitions.flagValues
: Simplified feature flags that contain only a value.segments
: User segment definitions.
The format of the data in flags
and segments
is defined by the LaunchDarkly application
and is subject to change. Rather than trying to construct these objects yourself, it is simpler
to request existing flags directly from the LaunchDarkly server in JSON format, and use this
output as the starting point for your file. In Linux you would do this:
curl -H "Authorization: YOUR_SDK_KEY" https://app.launchdarkly.com/sdk/latest-all
The output will look something like this (but with many more properties):
{
"flags": {
"flag-key-1": {
"key": "flag-key-1",
"on": true,
"variations": [ "a", "b" ]
}
},
"segments": {
"segment-key-1": {
"key": "segment-key-1",
"includes": [ "user-key-1" ]
}
}
}
Data in this format allows the SDK to exactly duplicate all the kinds of flag behavior supported by LaunchDarkly. However, in many cases you will not need this complexity, but will just want to set specific flag keys to specific values. For that, you can use a much simpler format:
{
"flagValues": {
"my-string-flag-key": "value-1",
"my-boolean-flag-key": true,
"my-integer-flag-key": 3
}
}
Or, in YAML:
flagValues:
my-string-flag-key: "value-1"
my-boolean-flag-key: true
my-integer-flag-key: 1
It is also possible to specify both "flags" and "flagValues", if you want some flags to have simple values and others to have complex behavior. However, it is an error to use the same flag key or segment key more than once, either in a single file or across multiple files.
If the data source encounters any error in any file-- malformed content, a missing file, or a duplicate key-- it will not load flags from any of the files.
Class Method Summary collapse
-
.factory(options = {}) ⇒ Object
Returns a factory for the file data source component.
Class Method Details
.factory(options = {}) ⇒ Object
Returns a factory for the file data source component.
118 119 120 |
# File 'lib/ldclient-rb/file_data_source.rb', line 118 def self.factory(={}) return lambda { |sdk_key, config| FileDataSourceImpl.new(config.feature_store, config.logger, ) } end |