Excluding (Restricting) and Aliasing Directives

When an organization wants to expose the Wrangler to its end users, they would like to have the ability to restrict (exclude) directives that are not considered "safe". Safe is very subjective and varies from organization to organization. Also, the "Safe"ness of a data operation could go through approval process and later excluded from the restricted list. So, in short, the capability to restrict and un-restrict has be easily configurable.

Second common use-case we have seen is that an organization is accustomed to an organizational jargon and it's hard to adapt, it's not impossible, it just hard.

In order to support these kind of usage, the Wrangler has added the capability to exclude and as well as alias a directive with a simple configuration.

Feature

There are two configuration supported by the Wrangler:

Exclusion (a.k.a Restriction) and
Aliasing

Exclusion allows administrators to specify a list of directives either root directive or aliased directive that should be restricted from invocation and as well as application.

Aliasing allows one to create a new name for a root directive.

Scope

Both Exclusion and Aliasing are namespace wide - meaning they are applicable only within the namespace were the configuration has been applied.

Configuration

Configuration is currently specified as a JSON object with main keys namely

exclusions
aliases

Following is a high-level JSON object

{
    "exclusions" : [
      "root-directive",
      ...
      "root-directive"
    ],

    "aliases" : {
      "alias" : "alias-name",
      ...
      "alias" : "alias-name"
    }
}

Exclusion

It's an array of directives that are either loaded by default or could be loaded as UDD (User Defined Directives) or they can also be aliased directives.

Aliases

Is map of aliased directive and the actual directive name to which it's aliased.

Applying Configuration

A service endpoint exists to apply the configuration. In order to apply the configuration, use following REST call.

curl -s -X POST @<path-to-json>/<filename.json> \
 "http://<hostname>:11015/v3/namespaces/<namepsace>/apps/dataprep/services/service/methods/config"

And example would be

curl -s -X POST --data-binary @/tmp/wrangler-config.json \
 http://localhost:11015/v3/namespaces/default/apps/dataprep/services/service/methods/config \
  | python -mjson.tool
{
    "message": "Successfully updated configuration.",
    "status": 200
}