# Search and Replace Specific Terms

<p className="subtitle">
	Create a batch change that changes specific words in every repository.
</p>

This example shows you how to create [a batch spec](/batch-changes/create-a-batch-change) that replaces the words `whitelist` and `blacklist` with `allowlist` and `denylist` in every Markdown file across your entire code base.

The batch spec can be easily changed to search and replace other terms in other file types.

![use_allowlist_denylist_wording_teaser](https://sourcegraphstatic.com/docs/images/batch_changes/use_allowlist_denylist_wording_teaser.png)

## Prerequisites

<Callout type="tip">
	It's recommended to use the latest version of Sourcegraph when working with
	Batch Changes.
</Callout>

Before you start, it's better to read the following docs:

-   [Batch Changes Quickstart](/batch-changes/quickstart)
-   [How to create and run a Batch Spec?](/batch-changes/create-a-batch-change)

## Create the batch spec

Save the following batch spec YAML as `allowlist-denylist.batch.yaml`:

```yaml
name: use-allowlist-denylist-wording
description: This batch change updates our Markdown docs to use the terms "allowlist" and "denylist" instead of "whitelist" and "blacklist".

# Search for repositories in which the term "whitelist" or "blacklist" appears
# in Markdown files.
on:
    - repositoriesMatchingQuery: whitelist OR blacklist lang:markdown -file:vendor -file:node_modules

# In each repository
steps:
    # find all * or *.markdown files, that are not in a vendor or node_modules
    # folder, and replace the terms in them:
    - run: |
          find . -type f \( -name '*' -or -name '*.markdown' \) -not -path "*/vendor/*" -not -path "*/node_modules/*" |\
          xargs sed -i 's/whitelist/allowlist/g; s/blacklist/denylist/g'
      container: alpine:3

# Describe the changeset (e.g., GitHub pull request) you want for each repository.
changesetTemplate:
    title: Replace whitelist/blacklist with allowlist/denylist
    body: This replaces the terms whitelist/blacklist in Markdown files with allowlist/denylist
    branch: batch-changes/allowlist-denylist # Push the commit to this branch.
    commit:
        message: Replace whitelist/blacklist with allowlist/denylist
    published: false
```

## Create the batch change

1. In your terminal, run the following command:

```shell
src batch preview -f use-allowlist-denylist-wording.batch.yaml
```

-   Wait for it to run and compute the changes for each repository

![use_allowlist_denylist_wording_wait_run](https://sourcegraphstatic.com/docs/images/batch_changes/use_allowlist_denylist_wording_wait_run.png)

-   Open the preview URL that the command printed out

![use_allowlist_denylist_wording_click_url](https://sourcegraphstatic.com/docs/images/batch_changes/use_allowlist_denylist_wording_click_url.png)

-   Examine the preview. Confirm that the changes are what you intended. If not, edit your batch spec and then re-run the command above

![use_allowlist_denylist_wording_preview](https://sourcegraphstatic.com/docs/images/batch_changes/use_allowlist_denylist_wording_preview.png)

-   Click the **Apply** button to create the batch change
-   Feel free to then publish the changesets (i.e., create pull requests and merge requests) by [modifying the `published` attribute in the batch spec](/batch-changes/batch-spec-yaml-reference#changesettemplatepublished) and re-running the `src batch preview` command

## Using `ruplacer` to replace terms in multiple case styles

With [ruplacer](https://github.com/TankerHQ/ruplacer) we can easily search and replace terms in multiple case styles: `white_list`, `WhiteList`, `WHITE_LIST` etc.

The easiest way to use `ruplacer` in our batch spec would look like this:

```yaml
steps:
    - run: |
          find . -type f \( -name '*' -or -name '*.markdown' \) -not -path "*/vendor/*" -not -path "*/node_modules/*" >> /tmp/find_result.txt \
          && cat /tmp/find_result.txt | while read file;
          do
            ruplacer --subvert whitelist allowlist --go ${file} || echo "nothing to replace";
            ruplacer --subvert blacklist denylist --go ${file} || echo "nothing to replace";
          done
      container: keegancsmith/ruplacer
```

Save the file and run the `src batch preview` command from above again to use `ruplacer` to replace variations of terms. Alternatively if you want to run it on all files:

```yaml
steps:
    - run: |
          ruplacer --subvert whitelist allowlist --go || echo "nothing to replace"
          ruplacer --subvert blacklist denylist --go  || echo "nothing to replace"
      container: keegancsmith/ruplacer
```