SQLite Sync: Addressing Critical Blocking Issues

🛠️ Resolving Critical Issues in SQLite Sync PR #72

Let's dive into the core challenges and fixes needed for the SQLite sync implementation in pull request (PR) #72. This PR aims to introduce a robust SQLite sync system. However, several critical issues currently prevent its integration. This article provides a comprehensive overview of the problems, along with the necessary steps to get this feature merged.

Understanding the Scope of the Challenge

Before we begin, it's essential to understand that this PR is a critical step towards offline functionality and data synchronization. The goal is to allow users to work with their data even without an internet connection, with changes synced back to the server when connectivity is restored. However, the current state of the PR reveals several blocking issues, primarily stemming from compilation errors, structural inconsistencies, and the absence of critical features. Addressing these issues is paramount before the PR can be merged into the main branch. The issues are categorized based on their severity. These are compilation errors, breaking changes, and high-priority issues.

🚨 Compilation Errors: Immediate Hurdles

Compilation errors are the most immediate and critical issues. These prevent the code from even compiling, making it impossible to test or use the intended functionality. Let's analyze each of the compilation errors identified in the PR.

1. Type Mismatches in backend/sqliteBackend.go: Time Handling

The most prominent issue involves incorrect handling of time.Time values within the sqliteBackend.go file. The Task struct was updated to use non-pointer time.Time fields for Created and Modified. Still, the existing code in sqliteBackend.go attempts to treat them as pointers. This results in type mismatches and prevents the code from compiling. To resolve this, all references to the Created and Modified fields within the sqliteBackend.go file need to be updated. This involves either modifying the code to correctly handle non-pointer time.Time values or reverting the Task struct to use pointers. Specifically, lines 335-341 and line 360, and beyond. This is one of the main issues for SQLite sync to resolve the compilation error.

2. Non-Existent Field: task.ListID: Missing References

Another compilation error arises from a reference to a non-existent field, task.ListID, within sqliteBackend.go. Line 224 attempts to assign the value of task.ListID. However, the Task struct does not have a field with this name. This error needs to be addressed either by removing the field assignment or by adding the ListID field to the Task struct if it's necessary for the SQLite backend. The absence of this field causes a compilation error.

3. Missing TaskFilter Field: CreatedBefore: Filter Logic

Similar to the previous error, a reference to a non-existent field in the TaskFilter struct causes a compilation failure. Lines 198-200 within sqliteBackend.go reference filter.CreatedBefore. However, the current TaskFilter struct only defines CreatedAfter, not CreatedBefore. To resolve this, either the CreatedBefore field must be added to the TaskFilter struct, or the code referencing it needs to be removed. This ensures the filter logic works as intended and compiles without errors.

4. Private Method Access from CLI Package: Encapsulation Issues

This issue involves an attempt to access a private method, getDB(), from the cmd/gosynctasks/sync.go file. Private methods are not accessible from outside the package where they are defined, which leads to compilation errors. To fix this, several options are available. The simplest solution is to make the getDB() method public by renaming it to GetDB(). Alternatively, a public wrapper method could be created to provide controlled access to the database functionality. Another approach involves refactoring the code to avoid direct database access from the CLI package, which promotes better code organization and maintainability.

5. Duplicate Test Helper Declarations: Code Duplication

The final compilation error relates to duplicate declarations of test helpers across multiple test files. Specifically, the MockBackend type and the createTestBackend() function are declared in several test files, leading to a