Extract Schema Compare Contracts and Interfaces to SqlCore

[bruzel]

Extract Schema Compare Contracts and Interfaces to SqlCore (Phase 2/3)

Description

Phase 2 of the Schema Compare refactoring (Phase 1: PR #2635). Extracts shared type infrastructure into SqlCore so Schema Compare operations can be consumed by multiple hosts (VSCode/ADS, SSMS).
Full plan: schema-compare-migration-plan.md.

No behavioral changes. Operations remain in ServiceLayer and work identically. This is purely structural preparation for Phase 3 (operation migration + adapter pattern).

Phase	Description	Status
Phase 1	Multi-Framework Target & Conditional Compilation	✅ Completed (PR #2635)
Phase 2	Contracts, Interfaces & DeploymentOptions Foundation	🔄 This PR
Phase 3	Operation Refactoring, Adapters & Service Rewiring	📋 Planned

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What moved to SqlCore

• DeploymentOptions and DacFxUtils — relocated with namespace change from ServiceLayer.DacFx → SqlCore.DacFx
• Added DeploymentScenario enum to DeploymentOptions so dacfx/getDeploymentOptions can return scenario-appropriate defaults (SchemaCompare vs Deployment)
• Added GetDefaultPublishOptions() factory for publish-specific defaults

What's new in SqlCore

• ISchemaCompareConnectionProvider — abstracts connection string/token retrieval (decouples from ConnectionService)
• ISchemaCompareScriptHandler — abstracts script delivery (decouples from SqlTask)
• AccessTokenProvider — DacFx IUniversalAuthProvider impl for Azure MFA
• Contract types in SqlCore/SchemaCompare/Contracts/:
  • SchemaCompareContracts.cs — domain types (DiffEntry, SchemaCompareEndpointInfo, SchemaCompareEndpointType)
  • SchemaCompareParams.cs — all parameter types
  • SchemaCompareResults.cs — all result types

ServiceLayer contract changes

ServiceLayer contracts now extend SqlCore base types, adding only host-specific fields:

SqlCore.SchemaCompareParams              ServiceLayer.SchemaCompareParams
├─ OperationId                           ├─ (inherits all)
├─ SourceEndpointInfo        ◄─extends── ├─ + TaskExecutionMode
├─ TargetEndpointInfo                    └─ SourceEndpointInfo adds ConnectionDetails
└─ DeploymentOptions

Types like SchemaCompareEndpointType, DiffEntry, and SchemaCompareObjectId are removed from ServiceLayer (now imported from SqlCore).

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Architecture: Before → After Phase 2 → After Phase 3

Before (main branch)

┌─────────────────────────────────────────────────┐
│            Microsoft.SqlTools.ServiceLayer       │
│                                                  │
│  SchemaCompareService ──→ Operations             │
│       │                      │                   │
│       │                      ├─ ConnectionInfo   │
│       │                      ├─ SqlTask          │
│       │                      └─ ITaskOperation   │
│                                                  │
│  DacFx/Contracts/DeploymentOptions               │
│  DacFx/DacFxUtils                                │
│  SchemaCompare/Contracts/ (enums, DiffEntry, etc)│
└──────────────────────────────────────────────────┘
                  Everything in one layer

After Phase 2 (this PR) — shared types extracted

┌──────────────────────────────────────────────────┐
│             Microsoft.SqlTools.SqlCore            │
│                                                   │
│  DacFx/Contracts/DeploymentOptions  ◄── moved     │
│  DacFx/DacFxUtils                   ◄── moved     │
│  SchemaCompare/                                    │
│    ├─ ISchemaCompareConnectionProvider  ◄── NEW    │
│    ├─ ISchemaCompareScriptHandler       ◄── NEW    │
│    ├─ AccessTokenProvider               ◄── NEW    │
│    └─ Contracts/                        ◄── NEW    │
│        ├─ SchemaCompareContracts.cs                │
│        ├─ SchemaCompareParams.cs                   │
│        └─ SchemaCompareResults.cs                  │
└───────────────────────────┬──────────────────────┘
                            │ references (project ref)
┌───────────────────────────┴──────────────────────┐
│            Microsoft.SqlTools.ServiceLayer        │
│                                                   │
│  SchemaCompareService ──→ Operations              │
│       │                      │                    │
│       │              (unchanged — still use       │
│       │               ConnectionInfo, SqlTask)    │
│                                                   │
│  SchemaCompare/Contracts/                         │
│    └─ extend SqlCore base types                   │
│       (add TaskExecutionMode, ConnectionDetails)  │
└───────────────────────────────────────────────────┘
        Operations still in ServiceLayer (no behavior change)

After Phase 3 (next PR) — operations moved, adapters added

┌──────────────────────────────────────────────────┐
│             Microsoft.SqlTools.SqlCore            │
│                                                   │
│  DacFx/Contracts/DeploymentOptions                │
│  DacFx/DacFxUtils                                 │
│  SchemaCompare/                                    │
│    ├─ Interfaces (connection, script)              │
│    ├─ SchemaCompareOperation          ◄── moved    │
│    ├─ SchemaCompareGenerateScriptOp   ◄── moved    │
│    ├─ SchemaComparePublish*Operation  ◄── moved    │
│    ├─ SchemaCompareOpenScmpOperation  ◄── moved    │
│    ├─ SchemaCompareSaveScmpOperation  ◄── moved    │
│    ├─ SchemaCompareInclude*Operation  ◄── moved    │
│    ├─ SchemaCompareUtils              ◄── moved    │
│    └─ Contracts/                                   │
└───────────────────────────┬──────────────────────┘
                            │
┌───────────────────────────┴──────────────────────┐
│            Microsoft.SqlTools.ServiceLayer        │
│                                                   │
│  SchemaCompareService                             │
│    ├─ creates VsCodeConnectionProvider            │
│    ├─ creates VsCodeScriptHandler                 │
│    └─ wraps operations in TaskAdapter             │
│                                                   │
│  Adapters (NEW):                                  │
│    ├─ VsCodeConnectionProvider   ◄── implements   │
│    ├─ VsCodeScriptHandler        ◄── implements   │
│    └─ SchemaCompareTaskAdapter   ◄── ITaskOp wrap │
│                                                   │
│  SchemaCompare/Contracts/ (wire-format types)     │
└───────────────────────────────────────────────────┘
     SSMS can now directly use SqlCore operations
     with its own ISchemaCompareConnectionProvider

---

How ServiceLayer contracts extend SqlCore types

The key design pattern: SqlCore defines host-agnostic base types, ServiceLayer adds host-specific fields (TaskExecutionMode, ConnectionDetails):

SqlCore.SchemaCompareEndpointInfo              ServiceLayer.SchemaCompareEndpointInfo
┌─────────────────────────────┐               ┌──────────────────────────────────┐
│  EndpointType               │               │  (inherits all SqlCore fields)   │
│  ServerName                 │ ◄──extends──  │  + ConnectionDetails             │
│  DatabaseName               │               │    (VSCode/ADS-specific)         │
│  OwnerUri, PackageFilePath  │               └──────────────────────────────────┘
│  ExtractTarget, etc.        │
└─────────────────────────────┘

---

File change summary (~39 files)

Category	Count	Nature of change
SqlCore — moved	2	DeploymentOptions.cs, DacFxUtils.cs (namespace change)
SqlCore — new	7	3 interfaces + 3 contract files + migration plan doc
ServiceLayer contracts — updated	8	Extend SqlCore base types, remove duplicated enums/classes
ServiceLayer DacFx/SqlPackage — updated	10	using statement updates only
ServiceLayer operations — updated	6	using statement updates only
Test files — updated	6	using statement updates only
Total	~39	~1,234 insertions, ~211 deletions

~75% of the modified ServiceLayer files are using statement changes only — the actual structural work is in the 9 new/moved SqlCore files and 8 updated ServiceLayer contracts.

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Reviewer guide

1. Start with the migration plan — schema-compare-migration-plan.md for full context
2. Review new SqlCore types (the core of this PR):
   • SqlCore/SchemaCompare/ISchemaCompareConnectionProvider.cs
   • SqlCore/SchemaCompare/ISchemaCompareScriptHandler.cs
   • SqlCore/SchemaCompare/Contracts/SchemaCompareContracts.cs
   • SqlCore/SchemaCompare/Contracts/SchemaCompareParams.cs
   • SqlCore/SchemaCompare/Contracts/SchemaCompareResults.cs
3. Review moved files — DeploymentOptions.cs and DacFxUtils.cs (namespace changes + DeploymentScenario enum addition)
4. Spot-check ServiceLayer contracts — SchemaCompareRequest.cs is the most significant; others follow the same pattern
5. Skip using-only changes — ~24 files are purely using statement additions

[Copilot]

Pull request overview

Phase 2 of the Schema Compare refactor, extracting host-agnostic Schema Compare and DacFx shared types into SqlCore so operations can later be reused by multiple hosts (e.g., VSCode/ADS, SSMS), while keeping current ServiceLayer operations intact.

Changes:

• Introduces new SqlCore Schema Compare interfaces and contract types (params/results/domain models).
• Moves DacFx shared types (DeploymentOptions, DacFxUtils) into SqlCore and updates ServiceLayer/tests to reference the new namespaces.
• Adds/updates a migration plan document describing the phased architecture changes.

Reviewed changes

Copilot reviewed 39 out of 39 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
test/Microsoft.SqlTools.ServiceLayer.UnitTests/SqlPackage/SqlPackageServiceTests.cs	Update DeploymentOptions contract namespace import to SqlCore.
test/Microsoft.SqlTools.ServiceLayer.UnitTests/SchemaCompare/SchemaCompareTests.cs	Update Schema Compare contracts import to SqlCore.
test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/SchemaCompare/SchemaCompareTestUtils.cs	Update DeploymentOptions import to SqlCore.
test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/SchemaCompare/SchemaCompareServiceTests.cs	Switch Schema Compare contract type references to SqlCore aliases.
test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/SchemaCompare/SchemaCompareServiceOptionsTests.cs	Update DacFx contracts import to SqlCore; add SqlCore alias usage.
test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/DacFx/DacFxServiceTests.cs	Update DacFx contracts import to SqlCore.
src/Microsoft.SqlTools.SqlCore/SchemaCompare/schema-compare-migration-plan.md	New/updated migration plan for phases 1–3.
src/Microsoft.SqlTools.SqlCore/SchemaCompare/ISchemaCompareScriptHandler.cs	New host abstraction for script delivery.
src/Microsoft.SqlTools.SqlCore/SchemaCompare/ISchemaCompareConnectionProvider.cs	New host abstraction for connection string/token resolution and parsing.
src/Microsoft.SqlTools.SqlCore/SchemaCompare/Contracts/SchemaCompareResults.cs	New host-agnostic Schema Compare result types.
src/Microsoft.SqlTools.SqlCore/SchemaCompare/Contracts/SchemaCompareParams.cs	New host-agnostic Schema Compare parameter types.
src/Microsoft.SqlTools.SqlCore/SchemaCompare/Contracts/SchemaCompareContracts.cs	New shared Schema Compare domain types (endpoint info, diff entries, etc.).
src/Microsoft.SqlTools.SqlCore/SchemaCompare/AccessTokenProvider.cs	New internal DacFx auth provider wrapper for access tokens.
src/Microsoft.SqlTools.SqlCore/DacFx/DacFxUtils.cs	Move + namespace update; make utility publicly accessible from SqlCore.
src/Microsoft.SqlTools.SqlCore/DacFx/Contracts/DeploymentOptions.cs	Move + add scenario-based defaulting + publish defaults factory.
src/Microsoft.SqlTools.ServiceLayer/SqlPackage/SqlPackageService.cs	Update DacFxUtils namespace import to SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SqlPackage/Contracts/GenerateSqlPackageCommandRequest.cs	Update DeploymentOptions type reference to SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/SchemaCompareUtils.cs	Alias Schema Compare domain types from SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/SchemaCompareSaveScmpOperation.cs	Update DacFxUtils namespace import to SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/SchemaCompareOperation.cs	Update DacFxUtils namespace import to SqlCore; alias DiffEntry from SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/SchemaCompareOpenScmpOperation.cs	Update DeploymentOptions import to SqlCore; alias endpoint/object id types from SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/SchemaCompareIncludeExcludeNodeOperation.cs	Alias DiffEntry from SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/SchemaCompareIncludeExcludeAllNodesOperation.cs	Alias DiffEntry from SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/Contracts/SchemaCompareSaveScmpRequest.cs	Import Schema Compare contract types from SqlCore.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/Contracts/SchemaCompareRequest.cs	Remove duplicated DiffEntry/endpoint enum definitions; import SqlCore equivalents.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/Contracts/SchemaComparePublishProjectChangesRequest.cs	Make params extend SqlCore base params and add TaskExecutionMode.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/Contracts/SchemaComparePublishDatabaseChangesRequest.cs	Make params extend SqlCore base params and add TaskExecutionMode.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/Contracts/SchemaCompareOpenScmpRequest.cs	Remove duplicated SchemaCompareObjectId; import SqlCore equivalents.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/Contracts/SchemaCompareIncludeExcludeNodeRequest.cs	Make params extend SqlCore base params and add TaskExecutionMode.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/Contracts/SchemaCompareIncludeExcludeAllNodesRequest.cs	Make params extend SqlCore base params and add TaskExecutionMode.
src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/Contracts/SchemaCompareGenerateScriptRequest.cs	Make params extend SqlCore base params and add TaskExecutionMode.
src/Microsoft.SqlTools.ServiceLayer/DacFx/GenerateDeployScriptOperation.cs	Update DacFxUtils namespace import to SqlCore.
src/Microsoft.SqlTools.ServiceLayer/DacFx/DeployOperation.cs	Update DacFxUtils namespace import to SqlCore.
src/Microsoft.SqlTools.ServiceLayer/DacFx/DacFxService.cs	Update imports to SqlCore DacFx types.
src/Microsoft.SqlTools.ServiceLayer/DacFx/Contracts/SavePublishProfileRequest.cs	Update DeploymentOptions import to SqlCore.
src/Microsoft.SqlTools.ServiceLayer/DacFx/Contracts/GetOptionsFromProfileRequest.cs	Update DeploymentOptions import to SqlCore.
src/Microsoft.SqlTools.ServiceLayer/DacFx/Contracts/GetDeploymentOptionsRequest.cs	Remove local DeploymentScenario enum; use SqlCore’s version.
src/Microsoft.SqlTools.ServiceLayer/DacFx/Contracts/GenerateDeployScriptRequest.cs	Update DeploymentOptions import to SqlCore.
src/Microsoft.SqlTools.ServiceLayer/DacFx/Contracts/DeployRequest.cs	Update DeploymentOptions import to SqlCore.

Comments suppressed due to low confidence (2)

src/Microsoft.SqlTools.SqlCore/DacFx/Contracts/DeploymentOptions.cs:123

• The XML doc for the parameterless DeploymentOptions ctor says it initializes Schema Compare defaults, but the implementation delegates to DeploymentScenario.Deployment. Either update the summary to match the behavior, or change the ctor to use the SchemaCompare scenario if that’s the intended default.
  src/Microsoft.SqlTools.SqlCore/DacFx/Contracts/DeploymentOptions.cs:169
• InitializeFromProfile performs synchronous file IO (File.ReadAllText) but still returns Task and is awaited by callers. Consider either restoring async IO (ReadAllTextAsync + async/await) to avoid blocking request threads, or make the method synchronous and update call sites accordingly.

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[Copilot]

Pull request overview

Copilot reviewed 39 out of 39 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (2)

src/Microsoft.SqlTools.SqlCore/DacFx/Contracts/DeploymentOptions.cs:123

• The XML doc says the parameterless DeploymentOptions() constructor initializes Schema Compare defaults, but it delegates to DeploymentScenario.Deployment. Please either update the comment to match the behavior (deployment defaults) or change the constructor to use SchemaCompare if that was intended (note this would be a behavioral change).
  src/Microsoft.SqlTools.SqlCore/DacFx/Contracts/DeploymentOptions.cs:170
• InitializeFromProfile returns a Task and is awaited by callers, but it performs a synchronous File.ReadAllText, which can block the request handler thread. Consider using async I/O for modern targets (e.g., ReadAllTextAsync on net8.0) and/or Task.Run for net472 to preserve the non-blocking behavior.

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[Copilot]

Pull request overview

Copilot reviewed 40 out of 40 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (4)

src/Microsoft.SqlTools.SqlCore/DacFx/Contracts/DeploymentOptions.cs:123

• The parameterless DeploymentOptions constructor summary says it initializes with Schema Compare defaults, but it delegates to DeploymentScenario.Deployment. This is either a misleading doc comment or a functional bug (callers using new DeploymentOptions() will not get the SchemaCompare-specific SSMS override defaults). Consider either changing the default ctor to use DeploymentScenario.SchemaCompare, or updating the XML docs and ensuring call sites explicitly request the intended scenario.
  src/Microsoft.SqlTools.SqlCore/DacFx/DacFxUtils.cs:66
• booleanOptionsDictionary = deploymentOptions.BooleanOptionsDictionary as Dictionary<...> can set booleanOptionsDictionary to null (e.g., if BooleanOptionsDictionary is null after deserialization or reassignment), which will then throw when iterating it. Since the property is already Dictionary<string, DeploymentOptionProperty<bool>>, consider avoiding the as cast and instead null-coalescing to an empty dictionary (or validating and throwing a clearer exception).
  src/Microsoft.SqlTools.SqlCore/DacFx/Contracts/DeploymentOptions.cs:169
• InitializeFromProfile is still Task-returning and awaited by callers, but it now performs a synchronous File.ReadAllText(profilePath) which will block the request handler thread. Consider restoring async I/O (ReadAllTextAsync) or changing the method to be synchronous (and updating callers) to avoid the "async method that blocks" pattern.
  src/Microsoft.SqlTools.SqlCore/DacFx/Contracts/DeploymentOptions.cs:153
• The DeploymentOptions(DeploymentScenario scenario) XML doc says the Deployment scenario uses "DacFx native defaults without any modifications", but ExcludeObjectTypes is always initialized with a schema-compare-specific exclude list and the ctor only initializes boolean options (no scenario-specific handling for ExcludeObjectTypes). This makes it unclear what defaults callers actually get for Deployment vs SchemaCompare. Consider either making ExcludeObjectTypes scenario-dependent (or set from DacDeployOptions) or adjusting the docs to match the current behavior.

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