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Remove empty keys

org.openrewrite.json.RemoveEmptyKeys

Remove mapping entries whose value is an empty object or array, such as those left behind by DeleteKey. Entries are removed from the inside out, so a chain of objects holding nothing but the removed entry is removed entirely. Array elements are left alone, since removing one shifts the indexes of its siblings.

Recipe source​

GitHub: RemoveEmptyKeys.java, Issue Tracker, Code Genome Project

This recipe is available under the Apache License Version 2.0.

Options​

TypeNameDescriptionExample
StringkeysOptional. A JsonPath expression bounding the cleanup. Keys it selects, and the keys nested within them, are eligible for removal. When omitted, the whole document is eligible.$..devDependencies
StringcascadeToOptional. A JsonPath expression letting removal continue outward past keys. A key this recipe empties is removed when cascadeTo selects it or nests it, so keys of $.spec.template with cascadeTo of $.spec goes on to remove spec once template is gone. Keys that were already empty outside keys are still left alone. When omitted, removal stops at the keys boundary.$.spec

Example​

Parameters​
ParameterValue
keysnull
cascadeTonull
Before​
{
  "name": "my-package",
  "engines": {},
  "version": "1.0.0"
}
After​
{
  "name": "my-package",
  "version": "1.0.0"
}

Usage​

This recipe has no required configuration parameters and comes from a rewrite core library. It can be activated directly without adding any dependencies.

OpenRewrite artifacts are distributed through the Code Genome Project repository (https://artifacts.codegenomeproject.org/maven), which requires authentication. Sign in to the Code Genome Project to create a download token, then in the snippets below replace USERNAME with the email or username you signed in with and TOKEN with that token. See the quickstart guide for details.

  1. Add the following to your build.gradle file:
    build.gradle
    plugins {
        id("org.openrewrite.rewrite") version("latest.release")
    }

    rewrite {
        activeRecipe("org.openrewrite.json.RemoveEmptyKeys")
        setExportDatatables(true)
    }

    repositories {
        mavenCentral()
        maven {
            url = "https://artifacts.codegenomeproject.org/maven"
            credentials {
                username = "USERNAME"
                password = "TOKEN"
            }
        }
    }
  2. Run gradle rewriteRun to run the recipe.

See how this recipe works across multiple open-source repositories​

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Data Tables​

Source files that had results​

org.openrewrite.table.SourcesFileResults

Source files that were modified by the recipe run.

Column NameDescription
Source path before the runThe source path of the file before the run. null when a source file was created during the run.
Source path after the runA recipe may modify the source path. This is the path after the run. null when a source file was deleted during the run.
Parent of the recipe that made changesIn a hierarchical recipe, the parent of the recipe that made a change. Empty if this is the root of a hierarchy or if the recipe is not hierarchical at all.
Recipe that made changesThe specific recipe that made a change.
Estimated time savingAn estimated effort that a developer to fix manually instead of using this recipe, in unit of seconds.
CycleThe recipe cycle in which the change was made.