Updates Using Field Masks

In the Google Ads API, updates are done using a field mask. The field mask lists all the fields you intend to change with the update, and any specified fields that are not in the field mask will be ignored, even if sent to the server.

FieldMaskUtil

The recommended way to generate field masks is using our built-in field mask utility, which hides a lot of the specific details and allows you to generate field masks automatically by monitoring the changes you make to the entity's fields.

Here's an example for updating a campaign:

campaign = client.resource(:Campaign)
campaign.resource_name = client.path.campaign(customer_id, campaign_id)

mask = client.field_mask.with campaign do
  campaign.status = client.enum(:CampaignStatus)::PAUSED
  campaign.network_settings = client.resource(:NetworkSettings)
  campaign.network_settings.target_search_network = client.wrapper.bool(false)
end

First, we create an empty Campaign object. Then, we set its resource name so that the API will know exactly which campaign we are updating.

The example uses the client.field_mask.with method on the campaign to begin the block encompassing the updates. At the end of this block, the utility will compare the current status of the campaign after the block with the initial status of the campaign before the block, and automatically produce a field mask enumerating the changed fields. You can then pass the returned mask directly to the update call.

Manually creating a mask

To create a field mask from scratch, you would first create a Google::Protobuf::FieldMask, then make an array populated with the names of all the fields you intend to change, and finally assign the array to the field mask's path field.

mask = Google::Protobuf::FieldMask.new
mask.path = ["status", "name"]