How can I see all the places an asset or entity is referenced? In Drupal 8, I have a requirement from a client that they be able to find a reference of a given asset (file, node, entity, etc) throughout a Drupal site. The ultimate goal is to know that if they want to delete this asset, it's not going to create 404 errors throughout the places on the site where this is referenced in other content.

I'm thinking about a Views page where the name or ID or some type of identifier would be a contextual filter and then would show a list of all nodes or blocks where that relationship exists.

Any thoughts on how to approach solving an issue like this?
Have you looked at /admin/structure/views/view/files? Is that what you need?

Otherwise, you might try your creating your own view of files at /admin/structure/views/add.

No matter the view, you will need to check the file before deletion as there will be no functionality to warn admins.

Then for content, I think it would just be a view of content focused on adding the Content Reference field (or whatever you content reference field_name is), which can show where references are coming from.

langcode: en
status: true
dependencies:
  config:
    - field.storage.node.field_content_reference
  module:
    - node
    - user
id: content_references
label: 'Content References'
module: views
description: ''
tag: ''
base_table: node_field_data
base_field: nid
core: 8.x
display:
  default:
    display_plugin: default
    id: default
    display_title: Master
    position: 0
    display_options:
      access:
        type: perm
        options:
          perm: 'access content'
      cache:
        type: tag
        options: {  }
      query:
        type: views_query
        options:
          disable_sql_rewrite: false
          distinct: false
          replica: false
          query_comment: ''
          query_tags: {  }
      exposed_form:
        type: basic
        options:
          submit_button: Apply
          reset_button: false
          reset_button_label: Reset
          exposed_sorts_label: 'Sort by'
          expose_sort_order: true
          sort_asc_label: Asc
          sort_desc_label: Desc
      pager:
        type: full
        options:
          items_per_page: 50
          offset: 0
          id: 0
          total_pages: null
          expose:
            items_per_page: false
            items_per_page_label: 'Items per page'
            items_per_page_options: '5, 10, 25, 50'
            items_per_page_options_all: false
            items_per_page_options_all_label: '- All -'
            offset: false
            offset_label: Offset
          tags:
            previous: '‹ Previous'
            next: 'Next ›'
            first: '« First'
            last: 'Last »'
          quantity: 9
      style:
        type: table
      row:
        type: fields
      fields:
        field_content_reference:
          id: field_content_reference
          table: node__field_content_reference
          field: field_content_reference
          relationship: none
          group_type: group
          admin_label: ''
          label: 'Referenced Content'
          exclude: false
          alter:
            alter_text: false
            text: ''
            make_link: false
            path: ''
            absolute: false
            external: false
            replace_spaces: false
            path_case: none
            trim_whitespace: false
            alt: ''
            rel: ''
            link_class: ''
            prefix: ''
            suffix: ''
            target: ''
            nl2br: false
            max_length: 0
            word_boundary: true
            ellipsis: true
            more_link: false
            more_link_text: ''
            more_link_path: ''
            strip_tags: false
            trim: false
            preserve_tags: ''
            html: false
          element_type: ''
          element_class: ''
          element_label_type: ''
          element_label_class: ''
          element_label_colon: true
          element_wrapper_type: ''
          element_wrapper_class: ''
          element_default_classes: true
          empty: ''
          hide_empty: false
          empty_zero: false
          hide_alter_empty: true
          click_sort_column: target_id
          type: entity_reference_label
          settings:
            link: true
          group_column: target_id
          group_columns: {  }
          group_rows: true
          delta_limit: 0
          delta_offset: 0
          delta_reversed: false
          delta_first_last: false
          multi_type: separator
          separator: ', '
          field_api_classes: false
          plugin_id: field
        title:
          id: title
          table: node_field_data
          field: title
          relationship: none
          group_type: group
          admin_label: ''
          label: 'Referenced By'
          exclude: false
          alter:
            alter_text: false
            text: ''
            make_link: false
            path: ''
            absolute: false
            external: false
            replace_spaces: false
            path_case: none
            trim_whitespace: false
            alt: ''
            rel: ''
            link_class: ''
            prefix: ''
            suffix: ''
            target: ''
            nl2br: false
            max_length: 0
            word_boundary: false
            ellipsis: false
            more_link: false
            more_link_text: ''
            more_link_path: ''
            strip_tags: false
            trim: false
            preserve_tags: ''
            html: false
          element_type: ''
          element_class: ''
          element_label_type: ''
          element_label_class: ''
          element_label_colon: true
          element_wrapper_type: ''
          element_wrapper_class: ''
          element_default_classes: true
          empty: ''
          hide_empty: false
          empty_zero: false
          hide_alter_empty: true
          click_sort_column: value
          type: string
          settings:
            link_to_entity: true
          group_column: value
          group_columns: {  }
          group_rows: true
          delta_limit: 0
          delta_offset: 0
          delta_reversed: false
          delta_first_last: false
          multi_type: separator
          separator: ', '
          field_api_classes: false
          entity_type: node
          entity_field: title
          plugin_id: field
      filters:
        status:
          value: '1'
          table: node_field_data
          field: status
          plugin_id: boolean
          entity_type: node
          entity_field: status
          id: status
          expose:
            operator: ''
          group: 1
        field_content_reference_target_id:
          id: field_content_reference_target_id
          table: node__field_content_reference
          field: field_content_reference_target_id
          relationship: none
          group_type: group
          admin_label: ''
          operator: 'not empty'
          value:
            min: ''
            max: ''
            value: ''
          group: 1
          exposed: false
          expose:
            operator_id: ''
            label: ''
            description: ''
            use_operator: false
            operator: ''
            identifier: ''
            required: false
            remember: false
            multiple: false
            remember_roles:
              authenticated: authenticated
            placeholder: ''
            min_placeholder: ''
            max_placeholder: ''
          is_grouped: false
          group_info:
            label: ''
            description: ''
            identifier: ''
            optional: true
            widget: select
            multiple: false
            remember: false
            default_group: All
            default_group_multiple: {  }
            group_items: {  }
          plugin_id: numeric
      sorts: {  }
      title: 'Content References'
      header: {  }
      footer: {  }
      empty: {  }
      relationships: {  }
      arguments: {  }
      display_extenders: {  }
    cache_metadata:
      max-age: -1
      contexts:
        - 'languages:language_content'
        - 'languages:language_interface'
        - url.query_args
        - 'user.node_grants:view'
        - user.permissions
      tags:
        - 'config:field.storage.node.field_content_reference'
  block_1:
    display_plugin: block
    id: block_1
    display_title: Block
    position: 1
    display_options:
      display_extenders: {  }
    cache_metadata:
      max-age: -1
      contexts:
        - 'languages:language_content'
        - 'languages:language_interface'
        - url.query_args
        - 'user.node_grants:view'
        - user.permissions
      tags:
        - 'config:field.storage.node.field_content_reference'





I am not sure about an all in one solution...