Upload File Size Limit (#3334)

# Description of Changes

The change this PR aims to introduce is a setting for enabling an upload
file size limit. The author of the issue mentioned in this PR wanted
this feature as they themselves enforced a limit of 50MB file sizes on
their NGINX configuration.
This was implemented by adding an entry to the
[settings.yml.template](e52fc0e478/src/main/resources/settings.yml.template)
file. This entry has two sub-configurations in which you declare if the
application should enable upload file size limiting and then you declare
the limit itself.

For this to be available in code, a new field in the
[System](e52fc0e478/src/main/java/stirling/software/SPDF/model/ApplicationProperties.java (L280))
class was added, one named `uploadLimit`.

After that, inside the [AppConfig](url) class, a new thymeleaf bean was
created, one called `uploadLimit`. This bean takes the values available
in the `System` class and creates a `long` value representing the limit
value. This value is interpreted as non-existent if it is `0`, otherwise
it is the value in `bytes` of the upload limit.

In order to make this value available in the
[common.html](e52fc0e478/src/main/resources/templates/fragments/common.html)
file, where the submitFile form is imported from, a new controller
[GlobalUploadLimitWebController](e52fc0e478/src/main/java/stirling/software/SPDF/controller/web/GlobalUploadLimitWebController.java)
was created. This controller has the tag `ControllerAdvice` so that
every controller has the `ModelAttributes` defined within it. I am not
sure if this was a good approach but upon first investigations, I
couldn't find another method to make these attributes available in every
Controller, or template. If there is already a place like this in the
code with this specific purpose, please let me know so I can fix it.

After making these attributes available, I updated the code in
`common.html`to now display the upload limit if it is defined. This was
done with localization in mind.

Lastly, the
[downloader.js](e52fc0e478/src/main/resources/static/js/downloader.js)
and
[fileInput.js](e52fc0e478/src/main/resources/static/js/fileInput.js)
files to include logic to enforce the upload limit if it is defined.

The UI updates, when the upload limit is defined, are as so:
<img width="708" alt="image"
src="https://github.com/user-attachments/assets/4852fa10-2ec3-45cb-83e6-41a102f256d4"
/>

When the limit is disabled, the page looks exactly as it did before any
implementation:
<img width="707" alt="image"
src="https://github.com/user-attachments/assets/21e5e810-ffdc-4a99-a16d-491aea103709"
/>\\

Thank you.

Closes #2903

---

## Checklist

### General

- [x] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [x] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [x] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md)
(if applicable)
- [x] I have performed a self-review of my own code
- [x] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [x] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [x] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [x] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing)
for more details.

---------

Co-authored-by: Anthony Stirling <77850077+Frooodle@users.noreply.github.com>

src/main/java/stirling/software/SPDF/config/AppConfig.java

@@ -20,6 +20,8 @@ import org.springframework.core.io.Resource;
 import org.springframework.core.io.ResourceLoader;
 import org.thymeleaf.spring6.SpringTemplateEngine;
 
+import com.posthog.java.shaded.kotlin.text.Regex;
+
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.model.ApplicationProperties;
@@ -107,6 +109,33 @@ public class AppConfig {
         return (rateLimit != null) ? Boolean.valueOf(rateLimit) : false;
     }
 
+    @Bean(name = "uploadLimit")
+    public long uploadLimit() {
+        String maxUploadSize =
+                applicationProperties.getSystem().getFileUploadLimit() != null
+                        ? applicationProperties.getSystem().getFileUploadLimit()
+                        : "";
+
+        if (maxUploadSize.isEmpty()) {
+            return 0;
+        } else if (!new Regex("^[1-9][0-9]{0,2}[KMGkmg][Bb]$").matches(maxUploadSize)) {
+            log.error(
+                    "Invalid maxUploadSize format. Expected format: [1-9][0-9]{0,2}[KMGkmg][Bb], but got: {}",
+                    maxUploadSize);
+            return 0;
+        } else {
+            String unit = maxUploadSize.replaceAll("[1-9][0-9]{0,2}", "").toUpperCase();
+            String number = maxUploadSize.replaceAll("[KMGkmg][Bb]", "");
+            long size = Long.parseLong(number);
+            return switch (unit) {
+                case "KB" -> size * 1024;
+                case "MB" -> size * 1024 * 1024;
+                case "GB" -> size * 1024 * 1024 * 1024;
+                default -> 0;
+            };
+        }
+    }
+
     @Bean(name = "RunningInDocker")
     public boolean runningInDocker() {
         return Files.exists(Paths.get("/.dockerenv"));

src/main/java/stirling/software/SPDF/controller/web/GlobalUploadLimitWebController.java

@@ -0,0 +1,30 @@
+package stirling.software.SPDF.controller.web;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ModelAttribute;
+
+@Component
+@ControllerAdvice
+public class GlobalUploadLimitWebController {
+
+    @Autowired() private long uploadLimit;
+
+    @ModelAttribute("uploadLimit")
+    public long populateUploadLimit() {
+        return uploadLimit;
+    }
+
+    @ModelAttribute("uploadLimitReadable")
+    public String populateReadableLimit() {
+        return humanReadableByteCount(uploadLimit);
+    }
+
+    private String humanReadableByteCount(long bytes) {
+        if (bytes < 1024) return bytes + " B";
+        int exp = (int) (Math.log(bytes) / Math.log(1024));
+        String pre = "KMGTPE".charAt(exp - 1) + "B";
+        return String.format("%.1f %s", bytes / Math.pow(1024, exp), pre);
+    }
+}

src/main/java/stirling/software/SPDF/model/ApplicationProperties.java

@@ -290,6 +290,7 @@ public class ApplicationProperties {
         private Boolean disableSanitize;
         private Boolean enableUrlToPDF;
         private CustomPaths customPaths = new CustomPaths();
+        private String fileUploadLimit;
 
         public boolean isAnalyticsEnabled() {
             return this.getEnableAnalytics() != null && this.getEnableAnalytics();

src/main/resources/messages_en_GB.properties

@@ -10,6 +10,9 @@ multiPdfPrompt=Select PDFs (2+)
 multiPdfDropPrompt=Select (or drag & drop) all PDFs you require
 imgPrompt=Select Image(s)
 genericSubmit=Submit
+uploadLimit=Maximum file size:
+uploadLimitExceededSingular=is too large. Maximum allowed size is
+uploadLimitExceededPlural=are too large. Maximum allowed size is
 processTimeWarning=Warning: This process can take up to a minute depending on file-size
 pageOrderPrompt=Custom Page Order (Enter a comma-separated list of page numbers or Functions like 2n+1) :
 pageSelectionPrompt=Custom Page Selection (Enter a comma-separated list of page numbers 1,5,6 or Functions like 2n+1) :

src/main/resources/messages_en_US.properties

@@ -10,6 +10,9 @@ multiPdfPrompt=Select PDFs (2+)
 multiPdfDropPrompt=Select (or drag & drop) all PDFs you require
 imgPrompt=Select Image(s)
 genericSubmit=Submit
+uploadLimit=Maximum file size:
+uploadLimitExceededSingular=is too large. Maximum allowed size is
+uploadLimitExceededPlural=are too large. Maximum allowed size is
 processTimeWarning=Warning: This process can take up to a minute depending on file-size
 pageOrderPrompt=Custom Page Order (Enter a comma-separated list of page numbers or Functions like 2n+1) :
 pageSelectionPrompt=Custom Page Selection (Enter a comma-separated list of page numbers 1,5,6 or Functions like 2n+1) :

src/main/resources/messages_pt_PT.properties

@@ -10,6 +10,9 @@ multiPdfPrompt=Selecione PDFs (2+)
 multiPdfDropPrompt=Selecione (ou arraste e solte) todos os PDFs necessários
 imgPrompt=Selecione Imagem(ns)
 genericSubmit=Submeter
+uploadLimit=Tamanho máximo de ficheiro:
+uploadLimitExceededSingular=é muito grande. O tamanho máximo permitido é
+uploadLimitExceededPlural=são muito grandes. O tamanho máximo permitido é
 processTimeWarning=Aviso: Este processo pode demorar até um minuto dependendo do tamanho do ficheiro
 pageOrderPrompt=Ordem Personalizada de Páginas (Insira uma lista de números de página separados por vírgulas ou Funções como 2n+1):
 pageSelectionPrompt=Seleção Personalizada de Páginas (Insira uma lista de números de página separados por vírgulas 1,5,6 ou Funções como 2n+1):

src/main/resources/settings.yml.template

@@ -110,6 +110,7 @@ system:
     operations:
       weasyprint: '' #Defaults to /opt/venv/bin/weasyprint
       unoconvert: '' #Defaults to /opt/venv/bin/unoconvert
+  fileUploadLimit: '' # Defaults to "". No limit when string is empty. Set a number, between 0 and 999, followed by one of the following strings to set a limit. "KB", "MB", "GB".
 
 ui:
   appName: '' # application's visible name

src/main/resources/static/js/downloader.js

@@ -43,6 +43,20 @@
       firstErrorOccurred = false;
       const url = this.action;
       let files = $('#fileInput-input')[0].files;
+      const uploadLimit = window.stirlingPDF?.uploadLimit ?? 0;
+      if (uploadLimit > 0) {
+        const oversizedFiles = Array.from(files).filter(f => f.size > uploadLimit);
+        if (oversizedFiles.length > 0) {
+          const names = oversizedFiles.map(f => `"${f.name}"`).join(', ');
+          if (names.length === 1) {
+            alert(`${names} ${window.stirlingPDF.uploadLimitExceededSingular} ${window.stirlingPDF.uploadLimitReadable}.`);
+          } else {
+            alert(`${names} ${window.stirlingPDF.uploadLimitExceededPlural} ${window.stirlingPDF.uploadLimitReadable}.`);
+          }
+          files = Array.from(files).filter(f => f.size <= uploadLimit);
+          if (files.length === 0) return;
+        }
+      }
       const formData = new FormData(this);
       const submitButton = document.getElementById('submitBtn');
       const showGameBtn = document.getElementById('show-game-btn');

src/main/resources/static/js/fileInput.js

@@ -196,6 +196,28 @@ function setupFileInput(chooser) {
 
     await checkZipFile();
 
+    const uploadLimit = window.stirlingPDF?.uploadLimit ?? 0;
+    if (uploadLimit > 0) {
+      const oversizedFiles = allFiles.filter(f => f.size > uploadLimit);
+      if (oversizedFiles.length > 0) {
+        const names = oversizedFiles.map(f => `"${f.name}"`).join(', ');
+        if (names.length === 1) {
+          alert(`${names} ${window.stirlingPDF.uploadLimitExceededSingular} ${window.stirlingPDF.uploadLimitReadable}.`);
+        } else {
+          alert(`${names} ${window.stirlingPDF.uploadLimitExceededPlural} ${window.stirlingPDF.uploadLimitReadable}.`);
+        }
+        allFiles = allFiles.filter(f => f.size <= uploadLimit);
+        const dataTransfer = new DataTransfer();
+        allFiles.forEach(f => dataTransfer.items.add(f));
+        input.files = dataTransfer.files;
+
+        if (allFiles.length === 0) {
+          inputContainer.querySelector('#fileInputText').innerHTML = originalText;
+          return;
+        }
+      }
+    }
+
     allFiles = await Promise.all(
       allFiles.map(async (file) => {
         let decryptedFile = file;

src/main/resources/templates/fragments/common.html

@@ -241,6 +241,10 @@
         window.stirlingPDF.sessionExpired = /*[[#{session.expired}]]*/ '';
         window.stirlingPDF.refreshPage = /*[[#{session.refreshPage}]]*/ 'Refresh Page';
         window.stirlingPDF.error = /*[[#{error}]]*/ "Error";
+        window.stirlingPDF.uploadLimit = /*[[${uploadLimit}]]*/ 0;
+        window.stirlingPDF.uploadLimitReadable = /*[[${uploadLimitReadable}]]*/ 'Unlimited';
+        window.stirlingPDF.uploadLimitExceededSingular = /*[[#{uploadLimitExceededSingular}]]*/ 'is too large. Maximum allowed size is';
+        window.stirlingPDF.uploadLimitExceededPlural = /*[[#{uploadLimitExceededPlural}]]*/ 'are too large. Maximum allowed size is';
       })();
   </script>
   <script type="module" th:src="@{'/pdfjs-legacy/pdf.mjs'}"></script>
@@ -289,8 +293,11 @@
       </div>
     </div>
     <div class="selected-files flex-wrap"></div>
+    <div class="text-muted small mt-0 text-end w-100" th:if="${uploadLimit != 0}">
+      <span th:text="#{uploadLimit}">Maximum file size: </span>
+      <span th:text="${uploadLimitReadable}"></span>
+    </div>
   </div>
-
   <div class="progressBarContainer" style="display: none; position: relative;">
     <div class="progress" style="height: 1rem;">
       <div class="progressBar progress-bar progress-bar-striped progress-bar-animated bg-success" role="progressbar"