# Breaking Changes - Prost-Reflect Migration
## Summary
This document lists all breaking changes introduced by the prost-reflect migration. Changes fall into three categories:
1. **Enum value format changes** - PascalCase → SCREAMING_SNAKE_CASE
2. **Format changes** - Quotes, numeric values → Enum names
3. **Behavioral changes** - Panic → Empty string
## Enum Value Changes (PascalCase → SCREAMING_SNAKE_CASE)
### General Status Values
| `"Enabled"` | `"ENABLED"` |
| `"Paused"` | `"PAUSED"` |
| `"Removed"` | `"REMOVED"` |
| `"Unspecified"` | `"UNSPECIFIED"` |
| `"Unknown"` | `"UNKNOWN"` |
### Advertising Channel Types
| `"Search"` | `"SEARCH"` |
| `"Display"` | `"DISPLAY"` |
| `"Shopping"` | `"SHOPPING"` |
| `"Video"` | `"VIDEO"` |
| `"PerformanceMax"` | `"PERFORMANCE_MAX"` |
### Bidding Strategy Types
| `"ManualCPC"` | `"MANUAL_CPC"` |
| `"MaximizeConversions"` | `"MAXIMIZE_CONVERSIONS"` |
| `"MaximizeConversionValue"` | `"MAXIMIZE_CONVERSION_VALUE"` |
| `"TargetCPA"` | `"TARGET_CPA"` |
| `"TargetROAS"` | `"TARGET_ROAS"` |
| `"TargetImpressionShare"` | `"TARGET_IMPRESSION_SHARE"` |
| `"EnhancedCpc"` (was `"Unsupported"`) | `"ENHANCED_CPC"` |
### Device Types
| `"Mobile"` | `"MOBILE"` |
| `"Desktop"` | `"DESKTOP"` |
| `"Tablet"` | `"TABLET"` |
### Day of Week
| `"Monday"` | `"MONDAY"` |
| `"Tuesday"` | `"TUESDAY"` |
| `"Wednesday"` | `"WEDNESDAY"` |
| `"Thursday"` | `"THURSDAY"` |
| `"Friday"` | `"FRIDAY"` |
| `"Saturday"` | `"SATURDAY"` |
| `"Sunday"` | `"SUNDAY"` |
### Campaign Serving Status
| `"Canceled"` | `"CANCELED"` |
| `"Suspended"` | `"SUSPENDED"` |
| `"Eligible"` | `"ELIGIBLE"` |
| `"Pending"` | `"PENDING"` |
### Campaign Primary Status Reasons
| `"CampaignPaused"` | `"CAMPAIGN_PAUSED"` |
| `"CampaignRemoved"` | `"CAMPAIGN_REMOVED"` |
| `"CampaignPending"` | `"CAMPAIGN_PENDING"` |
### Ad Group Criterion Types
| `"Keyword"` | `"KEYWORD"` |
### Statuses
| `"Approved"` | `"APPROVED"` |
| `"Reviewed"` | `"REVIEWED"` |
### Ad Types and Assets
| `"Headline"` | `"HEADLINE"` |
| `"Headline1"` | `"HEADLINE_1"` |
| `"Description"` | `"DESCRIPTION"` |
| `"Sitelink"` | `"SITELINK"` |
| `"Image"` | `"IMAGE"` |
| `"Webpage"` | `"WEBPAGE"` |
### Other Values
| `"Purchase"` | `"PURCHASE"` |
| `"Open"` | `"OPEN"` |
| `"Remarketing"` | `"REMARKETING"` |
| `"NegativeKeywords"` | `"NEGATIVE_KEYWORDS"` |
| `"Added"` | `"ADDED"` |
| `"Campaign"` | `"CAMPAIGN"` |
| `"GoogleAdsWebClient"` | `"GOOGLE_ADS_WEB_CLIENT"` |
| `"Update"` | `"UPDATE"` |
| `"Best"` | `"BEST"` |
| `"TenThousandToFiftyThousand"` | `"TEN_THOUSAND_TO_FIFTY_THOUSAND"` |
| `"LocationOfPresence"` | `"LOCATION_OF_PRESENCE"` |
### Asset Automation Settings
| `"TextAssetAutomation:OptedIn"` | `"TEXT_ASSET_AUTOMATION:OPTED_IN"` |
| `"GenerateVerticalYoutubeVideos:OptedOut"` | `"GENERATE_VERTICAL_YOUTUBE_VIDEOS:OPTED_OUT"` |
| ... (all asset_automation pairs follow proto-canonical naming) |
## Format Changes
### `change_event.changed_fields`
**Old**: `"'field1, field2'"` (values wrapped in single quotes)
**New**: `"field1, field2"` (no quotes)
### `keyword.match_type` / similar enum fields
**Old**: Numeric string values
- `"2"` → Exact
- `"3"` → Phrase
- `"4"` → Broad
**New**: Proto enum names
- `"EXACT"`
- `"PHRASE"`
- `"BROAD"`
### Debug Format for Messages
**Old**: Prost-generated struct debug format
**New**: `DynamicMessage` debug format
Note: Exact output may differ slightly for complex nested messages.
## Behavioral Changes
### Absent Resources
**Old**: Panics
**New**: Returns empty string `""`
Example:
```rust
// Old behavior - would panic
row.get("campaign.status") // panics if campaign is None
// New behavior - returns empty string
row.get("campaign.status") // returns ""
```
### Repeated Message Fields
Separator behavior is maintained:
- Message items: `"; "` (semicolon-space)
- Scalar items: `", "` (comma-space)
## Migration Guide
### Updating Test Assertions
```rust
// Before
assert_eq!(row.get("campaign.status"), "Enabled");
assert_eq!(row.get("campaign.bidding_strategy_type"), "ManualCPC");
assert_eq!(row.get("ad_group_criterion.keyword.match_type"), "3");
assert_eq!(row.get("change_event.changed_fields"), "'id, status'");
// After
assert_eq!(row.get("campaign.status"), "ENABLED");
assert_eq!(row.get("campaign.bidding_strategy_type"), "MANUAL_CPC");
assert_eq!(row.get("ad_group_criterion.keyword.match_type"), "PHRASE");
assert_eq!(row.get("change_event.changed_fields"), "id, status");
```
### Updating Application Code
If you have code that parses or compares enum values:
```rust
// Old
if row.get("campaign.status") == "Enabled" { ... }
// New
if row.get("campaign.status") == "ENABLED" { ... }
```
### Keyword Match Type Handling
```rust
// Old - if you were mapping numeric values manually
let match_type = row.get("keyword.match_type");
if match_type == "3" { /* phrase */ }
// New - direct enum name comparison
let match_type = row.get("keyword.match_type");
if match_type == "PHRASE" { /* phrase */ }
```
## Testing Checklist
- [ ] Campaign status changes (`ENABLED`, `PAUSED`, `REMOVED`)
- [ ] Campaign bidding strategy types (`MANUAL_CPC`, etc.)
- [ ] Advertising channel types (`SEARCH`, `DISPLAY`, etc.)
- [ ] Device types (`MOBILE`, `DESKTOP`, `TABLET`)
- [ ] Day of week values (`MONDAY`, `TUESDAY`, etc.)
- [ ] Keyword match types (`EXACT`, `PHRASE`, `BROAD`)
- [ ] Change event changed_fields (no quotes)
- [ ] All primary status reasons
- [ ] Asset automation settings format
- [ ] Absent resource behavior (empty string, not panic)
- [ ] Repeated field separators maintained
- [ ] Integration tests with real GAQL queries
## Rollback Plan
If issues arise during migration:
1. Revert `src/lib.rs` to the previous version (commit hash: `f9dad39`)
2. Optionally revert `build.rs`, `Cargo.toml`, and `utils/update.sh`
3. Note: May need to remove `optional` keyword stripping from protos again
However, rollback is not recommended long-term as the old implementation has:
- Limited resource support (~35 of ~178)
- High maintenance burden per API version
- Manual match arms for each field path