Customer.Api

This API exposes the following endpoints

• Contact information
  • Get a specific contact: GET /api/v{version}/customers/{customerId}/contacts/{contactId}
  • Get all contacts: GET /api/v{version}/customers/{customerId}/contacts
• Customer Information
  • Get a specific customer: GET /api/v{version}/customers/{customerId}
  • Get all customers: GET /api/v{version}/customers
  • Update an exising customer: PUT /api/v{version}/customers/{customerId}
• Note information
  • Get a specific note: GET /api/v{version}/customers/{customerId}/notes/{noteId}
  • Get all notes: /api/v{version}/customers/{customerId}/notes
  • Update an existing note: PUT /api/v{version}/customers/{customerId}/notes/{noteId}
  • Delete and exising note: DELETE /api/v{version}/customers/{customerId}/notes/{noteId}

The default APi version is 1. All identifiers are numbers.

How to run application

• Open solution in Visual Studio 2019
• Update connection string in appsettings.json by setting password that sent by email
• Run the project
• Use Swagger UI or Postman to send requests

Database

• I use SQL Server database hosted on Azure
• Currently the database server connection is public and you can access to the server sqltstauckl.database.windows.net using SSMS or Azure Data Studio with user/password from the connection string

Tables structure

CREATE TABLE Status
(
  StatusID TINYINT IDENTITY(1,1) NOT NULL
  ,Description VARCHAR(30) NOT NULL
  ,CreatedDateTimeUTC DATETIME NOT NULL
  CONSTRAINT DF_Status_CreateDateTimeUTC DEFAULT (SYSUTCDATETIME())
  ,UpdatedDateTimeUTC DATETIME NULL
  ,CONSTRAINT PK_Status PRIMARY KEY CLUSTERED (StatusID ASC)
)

CREATE TABLE Customer
(
  CustomerID INT IDENTITY(1,1) NOT NULL
  ,StatusID TINYINT NOT NULL
  ,FirstName VARCHAR(30) NULL
  ,LastName VARCHAR(60) NOT NULL
  ,CreatedDateTimeUTC DATETIME NOT NULL
  CONSTRAINT DF_Customer_CreateDateTimeUTC DEFAULT (SYSUTCDATETIME())
  ,UpdatedDateTimeUTC DATETIME NULL
  ,CONSTRAINT PK_Customer PRIMARY KEY CLUSTERED (CustomerID ASC)
  ,CONSTRAINT FK_Customer_Status_StatusID FOREIGN KEY (StatusID) REFERENCES Status(StatusID)
)

CREATE TABLE Contact
(
  ContactID INT IDENTITY(1,1) NOT NULL
  ,CustomerID INT
  ,Type CHAR(2) NOT NULL
  ,Detail VARCHAR(60) NOT NULL
  ,CreatedDateTimeUTC DATETIME NOT NULL
  CONSTRAINT DF_Contact_CreateDateTimeUTC DEFAULT (SYSUTCDATETIME())
  ,UpdatedDateTimeUTC DATETIME NULL
  ,CONSTRAINT FK_Contact_Customer_CustomerID FOREIGN KEY (CustomerID) REFERENCES Customer(CustomerID)
)

CREATE TABLE Note
(
  NoteID INT IDENTITY(1,1) NOT NULL
  ,CustomerID INT
  ,Detail VARCHAR(200) NOT NULL
  ,CreatedDateTimeUTC DATETIME NOT NULL
  CONSTRAINT DF_Note_CreateDateTimeUTC DEFAULT (SYSUTCDATETIME())
  ,UpdatedDateTimeUTC DATETIME NULL
  ,CONSTRAINT FK_Note_Customer_CustomerID FOREIGN KEY (CustomerID) REFERENCES Customer(CustomerID)
)

Notes

I spent on this project about 6-7 hours including

• Design a data model
• Build an app
• Set up and configuration SQL db on Azure
• Testing all endpoints with mix of data
• Writing this description :)

What I missed/would add

• Logging. We should add Serilog and logging middleware to store all requests/responses in log files/Elasticsearch. I would also send a message to TEams/Slack channel if any production issues occured.
• Validation. Currently, there is almost no a proper request validation. I would go with some custom implementation or use FluentValidation.
• There is no API authentication and authorisation. Ideally we shoud have an IdentityServer and probably database permissions to limit the access scope for the client.
• I created only a single Unit test however we need to cover all possible scenarios with all endpoints. Integration tests wouls be also an advantage.
• Thinking about possible performance issues, we will need to add non-clustered indexes on some heavily used columns.