Java Server for Dashboard Builder

Usage

In your terminal:

mvnw spring-boot:run

Core Files

There are several files that make up this sample:

• DomController.java: The class that parses the .rdash files and returns a JSON list to the client app.
• VisualizationChartInfo.java: The model class that represents a Visualization.
• DashboardNameInfo.java: The model class that represents the simplified dashboard information.

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DomController Class

The DomController class is a JAX-RS-based RESTful controller that exposes endpoints to retrieve visualizations and dashboard names from .rdash files. It processes the dashboards to extract relevant information and format it into JSON responses.

Imports

• Core Java Libraries: Used for file handling (File), I/O operations (BufferedReader, InputStream), and handling ZIP files.
• JSON Libraries: For JSON parsing and object manipulation.
• Jakarta RESTful Web Services (JAX-RS): For REST API annotations and functionality.

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REST Endpoints

@Path("/dashboards")

Defines the base path for all endpoints in this controller.

/visualizations

• HTTP Method: GET
• Path: /visualizations
• Response Format: application/json
• Description: Retrieves all visualizations from .rdash files stored in the dashboards folder.

/names

• HTTP Method: GET
• Path: /names
• Response Format: application/json
• Description: Retrieves the names and titles of all dashboards from .rdash files stored in the dashboards folder.

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Method Details

getRdashData()

• Purpose: Main function to process .rdash files and extract visualization data.
• Steps:
  1. Scans the dashboards folder for .rdash files.
  2. Reads each .rdash file as a ZIP archive to find and extract its .json content.
  3. Parses the extracted JSON to retrieve dashboard and widget information.
  4. Formats the data into VisualizationChartInfo objects.

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getDashboardNames()

• Purpose: Retrieves the names and titles of all dashboards.
• Steps:
  1. Scans the dashboards folder for .rdash files.
  2. Reads each .rdash file as a ZIP archive to find and extract its .json content.
  3. Parses the extracted JSON to retrieve the dashboard Title.
  4. Formats the data into DashboardNameInfo objects.

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extractJsonFromRdash(String filePath)

• Purpose: Extracts the JSON content from a .rdash file, treating it as a ZIP archive.
• Steps:
  1. Opens the .rdash file as a ZipFile.
  2. Finds entries ending with .json.
  3. Reads and returns the content of the .json entry as a string.

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extractTitleFromJson(String jsonContent)

• Purpose: Extracts the Title field from the JSON content of a dashboard.
• Default Behavior: Returns "Untitled" if no Title field exists.

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parseWidgetsFromJson(String jsonContent, String dashboardFileName, String dashboardTitle)

• Purpose: Parses the widgets array in the JSON content and maps it to a list of VisualizationChartInfo objects.
• Steps:
  1. Checks for the presence of a Widgets array in the JSON.
  2. Iterates through the widgets to extract:
     • Widget ID
     • Title
     • Visualization settings (e.g., type, view type, chart type)
  3. Determines the appropriate visualization chart type based on the settings.
  4. Generates the image URL for the chart type.
  5. Constructs and returns a list of VisualizationChartInfo objects.

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getImageUrl(String input)

• Purpose: Constructs an image URL for a given visualization chart type.
• Default Behavior: Appends .png to the chart type name, removing the suffix "Visualization" if present.

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Supporting Classes

The project includes the following supporting classes:

VisualizationChartInfo

• Purpose: Represents information about a single visualization chart.
• Fields:
  • dashboardFileName: The name of the dashboard file.
  • dashboardTitle: The title of the dashboard.
  • vizId: The unique ID of the visualization widget.
  • vizTitle: The title of the widget.
  • vizChartType: The type of the chart (e.g., Line, Bar, Gauge).
  • vizImageUrl: URL for the visualization chart image.

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DashboardNameInfo

• Purpose: Represents simplified information about a dashboard.
• Fields:
  • dashboardFileName: The name of the dashboard file.
  • dashboardTitle: The title of the dashboard.

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Key Features

1. Dynamic Parsing:

   • Automatically discovers .rdash files and extracts their visualization and name data without hardcoding file paths.

2. Flexible Chart Type Handling:

   • Supports multiple visualization types with fallbacks for unknown types.

3. Error Handling:

   • Logs errors when .rdash files are missing or malformed JSON is encountered.

4. Extensibility:

   • Easily extendable to handle additional visualization settings, dashboard metadata, or customization.

5. RESTful Design:

   • Simplifies integration with frontend or other services by providing structured JSON data.