Refactored service layer from pure functions to struct-based services #19

MichaelBoegner · 2025-10-16T06:23:51Z

Summary

This PR refactors the service layer from pure functions to struct-based services, introducing dependency injection and improved encapsulation. The changes move from a functional programming approach to an object-oriented service pattern.

What changed

Converting standalone functions to methods on service structs (UserService, TokenService, InterviewService, etc.)
Introducing service constructors that accept dependencies via dependency injection
Updating all handlers and tests to use the new service-based architecture

…dler

…ices

…vice to more scalable naming of AIService

Copilot

Pull Request Overview

This PR refactors the service layer from pure functions to struct-based services, introducing dependency injection and improved encapsulation. The changes move from a functional programming approach to an object-oriented service pattern.

Key changes include:

Converting standalone functions to methods on service structs (UserService, TokenService, InterviewService, etc.)
Introducing service constructors that accept dependencies via dependency injection
Updating all handlers and tests to use the new service-based architecture

Reviewed Changes

Copilot reviewed 31 out of 31 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
user/service.go	Converted user functions to UserService methods with dependency injection
user/service_test.go	Updated tests to use UserService struct instead of standalone functions
user/repository_mock.go	Changed mock field from private to public for external access
user/model.go	Added UserService struct and constructor
token/service.go	Converted token functions to TokenService methods
token/service_test.go	Updated tests to use TokenService struct
token/model.go	Added TokenService struct and constructor
interview/service.go	Converted interview functions to InterviewService methods
interview/service_test.go	Updated tests to use InterviewService struct
interview/model.go	Added InterviewService struct and constructor
conversation/service.go	Converted conversation functions to ConversationService methods
conversation/service_test.go	Updated tests to use ConversationService struct
conversation/model.go	Added ConversationService struct and constructor
mailer/service.go	Updated method receivers from Mailer to MailerService
mailer/model.go	Renamed Mailer struct to MailerService and updated constructor
chatgpt/service.go	Updated method receivers from OpenAIClient to AIService
chatgpt/model.go	Renamed OpenAIClient to AIService and updated constructor
billing/service.go	Converted billing functions to BillingService methods
billing/service_test.go	Updated tests to use BillingService struct
billing/model.go	Renamed Billing to BillingService and added dependency injection
dashboard/service.go	Converted dashboard functions to DashboardService methods
dashboard/model.go	Added DashboardService struct and constructor
handlers/model.go	Updated Handler struct to use service dependencies instead of repositories
handlers/handlers.go	Updated all handlers to use service methods instead of standalone functions
handlers/handlers_test.go	Updated tests to use new service-based architecture
internal/server/server.go	Updated server initialization to create and inject services
internal/testutil/server.go	Updated test server to use service-based architecture
internal/testutil/helpers.go	Updated helper functions to accept service parameters
internal/mocks/openai_mock.go	Renamed MockOpenAIClient to MockAIService
internal/mocks/mailer_mock.go	Renamed MockMailer to MockMailerService
learninglog/03_29_2025.md	Updated documentation to reflect new service naming

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dashboard/model.go

conversation/model.go

interview/service.go

handlers/handlers.go

internal/testutil/server.go

Copilot

Pull Request Overview

Copilot reviewed 31 out of 31 changed files in this pull request and generated 8 comments.

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

interview/service.go

Copilot · 2025-10-17T07:23:11Z

handlers/handlers.go

 	}

-	user, err := h.UserRepo.GetUser(params.UserID)
+	user, err := h.UserService.UserRepo.GetUser(params.UserID)


Direct access to h.UserService.UserRepo breaks encapsulation. This should use h.UserService.GetUser(params.UserID) to maintain proper abstraction boundaries.

Suggested change

user, err := h.UserService.UserRepo.GetUser(params.UserID)

user, err := h.UserService.GetUser(params.UserID)

Copilot · 2025-10-17T07:23:12Z

handlers/handlers.go

 	}

-	err = h.InterviewRepo.UpdateStatus(interviewID, userID, payload.Status)
+	err = h.InterviewService.InterviewRepo.UpdateStatus(interviewID, userID, payload.Status)


Direct access to h.InterviewService.InterviewRepo breaks encapsulation. Consider adding an UpdateStatus method to InterviewService to maintain proper abstraction boundaries.

Suggested change

err = h.InterviewService.InterviewRepo.UpdateStatus(interviewID, userID, payload.Status)

err = h.InterviewService.UpdateStatus(interviewID, userID, payload.Status)

Copilot · 2025-10-17T07:23:12Z

handlers/handlers.go

+	exists, err := h.BillingService.BillingRepo.HasWebhookBeenProcessed(webhookID)
 	if err != nil {
+		h.Logger.Error("h.BillingRepo.HasWebhookBeenProcessed failed", "error", err)


Direct access to h.BillingService.BillingRepo breaks encapsulation. Consider adding a HasWebhookBeenProcessed method to BillingService to maintain proper abstraction boundaries.

Suggested change

exists, err := h.BillingService.BillingRepo.HasWebhookBeenProcessed(webhookID)

if err != nil {

h.Logger.Error("h.BillingRepo.HasWebhookBeenProcessed failed", "error", err)

exists, err := h.BillingService.HasWebhookBeenProcessed(webhookID)

if err != nil {

h.Logger.Error("h.BillingService.HasWebhookBeenProcessed failed", "error", err)

Copilot · 2025-10-17T07:23:12Z

handlers/handlers.go

 		}

-		exists, err := h.UserRepo.HasActiveOrCancelledSubscription(SubCreatedAttrs.UserEmail)
+		exists, err := h.UserService.UserRepo.HasActiveOrCancelledSubscription(SubCreatedAttrs.UserEmail)


Direct access to h.UserService.UserRepo breaks encapsulation. Consider adding a HasActiveOrCancelledSubscription method to UserService to maintain proper abstraction boundaries.

Suggested change

exists, err := h.UserService.UserRepo.HasActiveOrCancelledSubscription(SubCreatedAttrs.UserEmail)

exists, err := h.UserService.HasActiveOrCancelledSubscription(SubCreatedAttrs.UserEmail)

Copilot · 2025-10-17T07:23:12Z

handlers/handlers.go

 	}

-	err = h.BillingRepo.MarkWebhookProcessed(webhookID, eventType)
+	err = h.BillingService.BillingRepo.MarkWebhookProcessed(webhookID, eventType)


Direct access to h.BillingService.BillingRepo breaks encapsulation. Consider adding a MarkWebhookProcessed method to BillingService to maintain proper abstraction boundaries.

Suggested change

err = h.BillingService.BillingRepo.MarkWebhookProcessed(webhookID, eventType)

err = h.BillingService.MarkWebhookProcessed(webhookID, eventType)

user/service.go

… methods to maintain consistency

MichaelBoegner added 30 commits October 4, 2025 10:56

added NewInterview service function and converted funcs to methods

16ff6dc

fixed integration and unit tests

b12e42e

added logger to new Interview service and service_test

7761284

removed unnecessary function

4c40218

converted user package services to methods

73d3baf

added user service instantiation to server.go

20673ef

fixed handlers_test to use new user service

7ab98fa

fixed service_test.go with NewUserService and logger instantiations

2838925

replaced user. calls with h.UserService calls

68b4309

fixed billing to use BillingService for BillingRepo and UserRepo

2abbdf1

fixed billing.service_test.go

d0f6c98

fixed test server billing.newBilling to include billingRepo and userRepo

caa9c85

converted token service to TokenService struct and methods

9666c88

converted token service to TokenService struct with methods

c18795a

added TokenService to handlers and handlers_test

567d69d

extracted token.CreateJWT from user service to be orchestrated in han…

bcde338

…dler

aligned OpenAI service with service naming being used in rest of serv…

122bfb5

…ices

further propegation of naming conversion as well as chaning OpenAISer…

839f360

…vice to more scalable naming of AIService

further changes to explicit naming of services

3da4b89

further clean up for billing services in handlers

8480db0

further cleanup in handlers for billing service naming

3e05661

converted dashboard service to struct and methods

df12fc9

started tackling conversation service conversion to struct and methods

17a3883

cleaned up conversation naming in handlers

fd90ac4

cleaned up tests

3d10acc

conversation converted to service struct and methods

70e01ef

fixed conversation tests

997414b

fixed billing service tests

9b71689

fixing user service test

78f8476

fixed TestLoginUser unit test

c4a0eb0

MichaelBoegner requested a review from Copilot October 16, 2025 06:23

MichaelBoegner self-assigned this Oct 16, 2025

MichaelBoegner added the enhancement New feature or request label Oct 16, 2025

Copilot AI reviewed Oct 16, 2025

View reviewed changes

dashboard/model.go Show resolved Hide resolved

conversation/model.go Outdated Show resolved Hide resolved

interview/service.go Outdated Show resolved Hide resolved

handlers/handlers.go Show resolved Hide resolved

internal/testutil/server.go Outdated Show resolved Hide resolved

MichaelBoegner added 2 commits October 16, 2025 14:02

resolved merge conflicts with main

dd9b247

fixing copilot suggestions

dbd06fc

MichaelBoegner requested a review from Copilot October 17, 2025 07:21

Copilot AI reviewed Oct 17, 2025

View reviewed changes

converted deductAndLogCredit and canUseCredit in interview service to…

bc2aa29

… methods to maintain consistency

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MichaelBoegner commented Oct 16, 2025 •

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	user, err := h.UserService.UserRepo.GetUser(params.UserID)
	user, err := h.UserService.GetUser(params.UserID)

	err = h.InterviewService.InterviewRepo.UpdateStatus(interviewID, userID, payload.Status)
	err = h.InterviewService.UpdateStatus(interviewID, userID, payload.Status)

	exists, err := h.UserService.UserRepo.HasActiveOrCancelledSubscription(SubCreatedAttrs.UserEmail)
	exists, err := h.UserService.HasActiveOrCancelledSubscription(SubCreatedAttrs.UserEmail)

	err = h.BillingService.BillingRepo.MarkWebhookProcessed(webhookID, eventType)
	err = h.BillingService.MarkWebhookProcessed(webhookID, eventType)

Refactored service layer from pure functions to struct-based services #19

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MichaelBoegner commented Oct 16, 2025 •

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