欄位遮罩

在 Google Ads API 中，更新作業會使用欄位遮罩完成。欄位遮罩清單 所有您想要變更更新的欄位，以及任何指定欄位 並忽略不在欄位遮罩中，即使已傳送至伺服器也是如此。

FieldMaskUtil

如要產生欄位遮罩，建議您使用內建欄位遮罩 公用程式，可讓您透過修改的物件產生欄位遮罩，而非 從頭開始建構

以下是更新廣告活動的範例：

// Creates a Campaign object with the proper resource name and any other changes.
Campaign campaign =
    Campaign.newBuilder()
        .setResourceName(ResourceNames.campaign(customerId, campaignId))
        .setStatus(CampaignStatus.PAUSED)
        .build();

// Constructs an operation that will update the campaign, using the FieldMasks'
// allSetFieldsOf utility to derive the update mask. This mask tells the Google
// Ads API which attributes of the campaign you want to change.
CampaignOperation operation =
    CampaignOperation.newBuilder()
        .setUpdate(campaign)
        .setUpdateMask(FieldMasks.allSetFieldsOf(campaign))
        .build();

// Sends the operation in a mutate request.
MutateCampaignsResponse response =
    campaignServiceClient.mutateCampaigns(
        customerId.toString(), Collections.singletonList(operation));

這個範例會先建立一個空白的 Campaign 物件，然後設定其資源 名稱讓 API 知道要更新哪個廣告活動。

這個範例在廣告活動中使用 FieldMasks.allSetFieldsOf() 方法： 自動產生欄位遮罩來列舉所有集合欄位。接著 將傳回的遮罩直接傳遞至更新呼叫。

若您需要使用現有物件來更新幾個欄位，則可以 請依下列方式修改程式碼：

Campaign existingCampaign;

// Obtains existingCampaign from elsewhere.
...

// Creates a new campaign based off the existing campaign and updates the
// campaign by setting its status to paused.
Campaign campaignToUpdate =
    existingCampaign.toBuilder()
        .setStatus(CampaignStatus.PAUSED)
        .build();

// Constructs an operation that will update the campaign, using the FieldMasks'
// compare utility to derive the update mask. This mask tells the Google Ads API
// which attributes of the campaign you want to change.
CampaignOperation operation =
    CampaignOperation.newBuilder()
        .setUpdate(campaignToUpdate)
        .setUpdateMask(FieldMasks.compare(existingCampaign, campaignToUpdate))
        .build();

// Sends the operation in a mutate request.
MutateCampaignsResponse response =
    campaignServiceClient.mutateCampaigns(
        customerId.toString(), Collections.singletonList(operation));

如要從頭建立欄位遮罩，您必須先建立 FieldMask敬上 物件，然後針對要更改為變更內容的每個欄位加入名稱 物件。

FieldMask fieldMask =
    FieldMask.newBuilder()
        .addPaths("status")
        .addPaths("name")
        .build();

更新訊息欄位及其子欄位

MESSAGE 欄位可包含子欄位 (例如 MaximizeConversions，其中包含三個： target_cpa_micros, cpc_bid_ceiling_micros 和 cpc_bid_floor_micros)，或者沒有 (例如 ManualCpm)。

未定義子欄位的訊息欄位

如要更新尚未以任何子欄位定義的 MESSAGE 欄位，請使用 FieldMaskUtil 用於產生欄位遮罩，如上所述。

含有已定義子欄位的訊息欄位

更新不含子欄位定義的 MESSAGE 欄位時 明確設定該訊息的任何子欄位，您必須手動 將每個可變動 MESSAGE 子欄位新增至 FieldMask，如下所示： 上述範例會從頭建立欄位遮罩。

有一個常見的例子，就是更新廣告活動的出價策略時，並未設定任何 新出價策略欄位的部分。以下範例說明如何 更新廣告活動 MaximizeConversions 出價策略 不必在出價策略中設定任何子欄位

在這種情況下，請使用 allSetFieldsOf() 和 compare() FieldMaskUtil 無法達到預期目標。

以下範例產生的欄位遮罩 maximize_conversions。但 Google Ads API 不允許此行為 可避免不小心清除欄位， FieldMaskError.FIELD_HAS_SUBFIELDS敬上 錯誤。

警告： 下列程式碼會產生錯誤。

// Creates a campaign with the proper resource name and an empty
// MaximizeConversions field.
Campaign campaign = Campaign.newBuilder()
    .setResourceName(ResourceNames.campaign(customerId, campaignId))
    .setMaximizeConversions(MaximizeConversions.newBuilder().build())
    .build();

// Constructs an operation, using the FieldMasks' allSetFieldsOf utility to
// derive the update mask. The field mask will include 'maximize_conversions`,
// which will produce a FieldMaskError.FIELD_HAS_SUBFIELDS error.
CampaignOperation operation =
    CampaignOperation.newBuilder()
        .setUpdate(campaign)
        .setUpdateMask(FieldMasks.allSetFieldsOf(campaign))
        .build();

// Sends the operation in a mutate request that will result in a
// FieldMaskError.FIELD_HAS_SUBFIELDS error because empty MESSAGE fields cannot
// be included in a field mask.
MutateCampaignsResponse response =
    campaignServiceClient.mutateCampaigns(
        customerId.toString(), Collections.singletonList(operation));

以下範例說明如何正確更新廣告活動，以便使用 MaximizeConversions出價策略，但未設定任何子欄位。

成效： 下方程式碼已成功更新廣告活動出價策略。

// Creates a Campaign object with the proper resource name.
Campaign campaign = Campaign.newBuilder()
    .setResourceName(ResourceNames.campaign(customerId, campaignId))
    .build();

// Creates a field mask from the existing campaign and adds all of the mutable
// fields (only one in this case) on the MaximizeConversions bidding strategy to
// the field mask. Because this field is included in the field mask but
// excluded from the campaign object, the Google Ads API will set the campaign's
// bidding strategy to a MaximizeConversions object without any of its subfields
// set.
FieldMask fieldMask = FieldMasks.allSetFieldsOf(campaign)
    .toBuilder()
    // Only include 'maximize_conversions.target_cpa_micros' in the field mask
    // as it is the only mutable subfield on MaximizeConversions when used as a
    // standard bidding strategy.
    //
    // Learn more about standard and portfolio bidding strategies here:
    // https://developers.google.com/google-ads/api/docs/campaigns/bidding/assign-strategies
    .addPaths("maximize_conversions.target_cpa_micros")
    .build();

// Creates an operation to update the campaign with the specified fields.
CampaignOperation operation =
    CampaignOperation.newBuilder()
        .setUpdate(campaign)
        .setUpdateMask(fieldMask)
        .build();

清除欄位

部分欄位可以明確清除。與上述範例類似，您必須 將這些欄位明確新增至欄位遮罩中。舉例來說 採用「MaximizeConversions」出價策略的廣告活動，且獲得 「target_cpa_micros」欄位的值必須大於 0。

接著程式碼就會執行。不過，maximize_conversions.target_cpa_micros 不會加到欄位遮罩中，也不會變更 target_cpa_micros 欄位：

警告： 這段程式碼不會產生錯誤，但 target_cpa_micros 系統不會清除 MaximizeConversions 的出價策略。

// Creates a campaign with the proper resource name and a MaximizeConversions
// object with target_cpa_micros set to 0.
Campaign campaign =
    Campaign.newBuilder()
        .setResourceName(ResourceNames.campaign(customerId, campaignId))
        .setMaximizeConversions(
            MaximizeConversions.newBuilder().setTargetCpa(0).build())
        .setStatus(CampaignStatus.PAUSED)
        .build();

// Constructs an operation, using the FieldMasks' allSetFieldsOf utility to
// derive the update mask. However, the field mask will NOT include
// 'maximize_conversions.target_cpa_micros'.
CampaignOperation operation =
    CampaignOperation.newBuilder()
        .setUpdate(campaign)
        .setUpdateMask(FieldMasks.allSetFieldsOf(campaign))
        .build();

// Sends the operation in a mutate request that will succeed but will NOT update
// the 'target_cpa_micros' field because
// 'maximize_conversions.target_cpa_micros' was not included in the field mask.
MutateCampaignsResponse response =
    campaignServiceClient.mutateCampaigns(
        customerId.toString(), Collections.singletonList(operation));

下一個範例說明如何正確清除 target_cpa_micros ] 欄位。MaximizeConversions

成功： 下列程式碼會清除 target_cpa_micros。

// Creates a Campaign object with the proper resource name.
Campaign campaign = Campaign.newBuilder()
    .setResourceName(ResourceNames.campaign(customerId, campaignId))
    .build();

// Constructs a field mask from the existing campaign and adds the
// 'maximize_conversions.target_cpa_micros' field to the field mask, which will
// clear this field from the bidding strategy without impacting any other fields
// on the bidding strategy.
FieldMask fieldMask = FieldMasks.allSetFieldsOf(campaign)
    .toBuilder()
    .addPaths("maximize_conversions.target_cpa_micros")
    .build();

// Creates an operation to update the campaign with the specified field.
CampaignOperation operation =
    CampaignOperation.newBuilder()
        .setUpdate(campaign)
        .setUpdateMask(fieldMask))
        .build();

請注意，即使上述範例對 在 Google Ads API 中定義為 optional protocol buffers。 但自從 target_cpa_micros敬上 不是 optional 欄位，「不正確」範例「不會」更新 出價策略，以便清除「target_cpa」欄位。

重點： 如果您的目的是清除某個欄位，這是最安全的方法 目的是明確將該欄位新增至欄位遮罩中。