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@ -298,3 +298,260 @@ When contributing translations:
3. The PR checks will verify consistency in language file updates.
Remember to test your changes thoroughly to ensure they don't break any existing functionality.
# Code examples
### Overview of Thymeleaf
Thymeleaf is a server-side Java HTML template engine. It is used in Stirling-PDF to render dynamic web pages. Thymeleaf integrates heavily with Spring Boot
### Thymeleaf overview
In Stirling-PDF, Thymeleaf is used to create HTML templates that are rendered on the server side. These templates are located in the `src/main/resources/templates` directory. Thymeleaf templates use a combination of HTML and special Thymeleaf attributes to dynamically generate content.
Some examples of this are
```html
<th:block th:insert="~{fragments/navbar.html :: navbar}"></th:block>
or
<th:block th:insert="~{fragments/footer.html :: footer}"></th:block>
```
Where it uses the th:block, th: indicating its a special thymeleaf element to be used serverside in generating the html, and block being the actual element type.
In this case we are inserting the ``navbar`` entry within the ``fragments/navbar.html`` fragment into the ``th:block`` element.
They can be more complex such as
```html
<th:block th:insert="~{fragments/common :: head(title=#{pageExtracter.title}, header=#{pageExtracter.header})}"></th:block>
```
Which is the same as above but passes the parameters title and header into the fragment common.html to be used in its HTML generation
Thymeleaf can also be used to loop through objects or pass things from java side into html side.
```java
@GetMapping
public String newFeaturePage(Model model) {
model.addAttribute("exampleData", exampleData);
return "new-feature";
}
```
in above example if exampleData is a list of plain java objects of class Person and within it you had id, name, age etc. You can reference it like so
```html
<tbody>
<!-- Use th:each to iterate over the list -->
<tr th:each="person : ${exampleData}">
<td th:text="${person.id}"></td>
<td th:text="${person.name}"></td>
<td th:text="${person.age}"></td>
<td th:text="${person.email}"></td>
</tr>
</tbody>
```
This would generate n entries of tr for each person in exampleData
### Adding a New Feature to the Backend (API)
1. **Create a New Controller:**
- Create a new Java class in the `src/main/java/stirling/software/SPDF/controller/api` directory.
- Annotate the class with `@RestController` and `@RequestMapping` to define the API endpoint.
- Ensure to add API documentation annotations like `@Tag(name = "General", description = "General APIs")` and `@Operation(summary = "Crops a PDF document", description = "This operation takes an input PDF file and crops it according to the given coordinates. Input:PDF Output:PDF Type:SISO")`.
```java
package stirling.software.SPDF.controller.api;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import io.swagger.v3.oas.annotations.Operation;
import io.swagger.v3.oas.annotations.tags.Tag;
@RestController
@RequestMapping("/api/v1/new-feature")
@Tag(name = "General", description = "General APIs")
public class NewFeatureController {
@GetMapping
@Operation(summary = "New Feature", description = "This is a new feature endpoint.")
public String newFeature() {
return "NewFeatureResponse"; // This refers to the NewFeatureResponse.html template presenting the user with the generated html from that file when they navigate to /api/v1/new-feature
}
}
```
2. **Define the Service Layer:** (Not required but often useful)
- Create a new service class in the `src/main/java/stirling/software/SPDF/service` directory.
- Implement the business logic for the new feature.
```java
package stirling.software.SPDF.service;
import org.springframework.stereotype.Service;
@Service
public class NewFeatureService {
public String getNewFeatureData() {
// Implement business logic here
return "New Feature Data";
}
}
```
2b. **Integrate the Service with the Controller:**
- Autowire the service class in the controller and use it to handle the API request.
```java
package stirling.software.SPDF.controller.api;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import stirling.software.SPDF.service.NewFeatureService;
import io.swagger.v3.oas.annotations.Operation;
import io.swagger.v3.oas.annotations.tags.Tag;
@RestController
@RequestMapping("/api/v1/new-feature")
@Tag(name = "General", description = "General APIs")
public class NewFeatureController {
@Autowired
private NewFeatureService newFeatureService;
@GetMapping
@Operation(summary = "New Feature", description = "This is a new feature endpoint.")
public String newFeature() {
return newFeatureService.getNewFeatureData();
}
}
```
### Adding a New Feature to the Frontend (UI)
1. **Create a New Thymeleaf Template:**
- Create a new HTML file in the `src/main/resources/templates` directory.
- Use Thymeleaf attributes to dynamically generate content.
- Use `extract-page.html` as a base example for the HTML template, useful to ensure importing of the general layout, navbar and footer.
```html
<!DOCTYPE html>
<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
<head>
<th:block th:insert="~{fragments/common :: head(title=#{newFeature.title}, header=#{newFeature.header})}"></th:block>
</head>
<body>
<div id="page-container">
<div id="content-wrap">
<th:block th:insert="~{fragments/navbar.html :: navbar}"></th:block>
<br><br>
<div class="container">
<div class="row justify-content-center">
<div class="col-md-6 bg-card">
<div class="tool-header">
<span class="material-symbols-rounded tool-header-icon organize">upload</span>
<span class="tool-header-text" th:text="#{newFeature.header}"></span>
</div>
<form th:action="@{'/api/v1/new-feature'}" method="post" enctype="multipart/form-data">
<div th:replace="~{fragments/common :: fileSelector(name='fileInput', multipleInputsForSingleRequest=false, accept='application/pdf')}"></div>
<input type="hidden" id="customMode" name="customMode" value="">
<div class="mb-3">
<label for="featureInput" th:text="#{newFeature.prompt}"></label>
<input type="text" class="form-control" id="featureInput" name="featureInput" th:placeholder="#{newFeature.placeholder}" required>
</div>
<button type="submit" id="submitBtn" class="btn btn-primary" th:text="#{newFeature.submit}"></button>
</form>
</div>
</div>
</div>
</div>
<th:block th:insert="~{fragments/footer.html :: footer}"></th:block>
</div>
</body>
</html>
```
2. **Create a New Controller for the UI:**
- Create a new Java class in the `src/main/java/stirling/software/SPDF/controller/ui` directory.
- Annotate the class with `@Controller` and `@RequestMapping` to define the UI endpoint.
```java
package stirling.software.SPDF.controller.ui;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import stirling.software.SPDF.service.NewFeatureService;
@Controller
@RequestMapping("/new-feature")
public class NewFeatureUIController {
@Autowired
private NewFeatureService newFeatureService;
@GetMapping
public String newFeaturePage(Model model) {
model.addAttribute("newFeatureData", newFeatureService.getNewFeatureData());
return "new-feature";
}
}
```
3. **Update the Navigation Bar:**
- Add a link to the new feature page in the navigation bar.
- Update the `src/main/resources/templates/fragments/navbar.html` file.
```html
<li class="nav-item">
<a class="nav-link" th:href="@{/new-feature}">New Feature</a>
</li>
```
## Adding New Translations to Existing Language Files in Stirling-PDF
When adding a new feature or modifying existing ones in Stirling-PDF, you'll need to add new translation entries to the existing language files. Here's a step-by-step guide:
### 1. Locate Existing Language Files
Find the existing `messages.properties` files in the `src/main/resources` directory. You'll see files like:
- `messages.properties` (default, usually English)
- `messages_en_GB.properties`
- `messages_fr.properties`
- `messages_de.properties`
- etc.
### 2. Add New Translation Entries
Open each of these files and add your new translation entries. For example, if you're adding a new feature called "PDF Splitter",
Use descriptive, hierarchical keys (e.g., `feature.element.description`)
you might add:
```properties
pdfSplitter.title=PDF Splitter
pdfSplitter.description=Split your PDF into multiple documents
pdfSplitter.button.split=Split PDF
pdfSplitter.input.pages=Enter page numbers to split
```
Add these entries to the default GB language file and any others you wish, translating the values as appropriate for each language.
### 3. Use Translations in Thymeleaf Templates
In your Thymeleaf templates, use the `#{key}` syntax to reference the new translations:
```html
<h1 th:text="#{pdfSplitter.title}">PDF Splitter</h1>
<p th:text="#{pdfSplitter.description}">Split your PDF into multiple documents</p>
<input type="text" th:placeholder="#{pdfSplitter.input.pages}">
<button th:text="#{pdfSplitter.button.split}">Split PDF</button>
```
Remember, never hard-code text in your templates or Java code. Always use translation keys to ensure proper localization.