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documentation/middleware.md

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+# Express Middleware Documentation for Embedder
+
+Embedder employs a series of middleware functions to facilitate operations such as user authentication, media conversions, and handling uploaded files.
+
+## Middleware Functions
+
+---
+
+### `checkAuth()`
+- **Description**: Ensures the user is authenticated.
+- **Parameters**:
+  - `req`: Express request object
+  - `res`: Express response object
+  - `next`: Callback to the next middleware function
+
+---
+
+### `checkSharexAuth()`
+- **Description**: Validates the ShareX authentication key provided in the headers.
+- **Parameters**:
+  - `req`: Express request object
+  - `res`: Express response object
+  - `next`: Callback to the next middleware function
+
+---
+
+### `createEmbedData()`
+- **Description**: Generates oEmbed metadata for embeds and saves them as JSON files.
+- **Parameters**:
+  - `req`: Express request object
+  - `res`: Express response object
+  - `next`: Callback to the next middleware function
+
+---
+
+### `convert()`
+- **Description**: Converts media files between video and GIF formats using ffmpeg.
+- **Parameters**:
+  - `req`: Express request object
+  - `res`: Express response object
+  - `next`: Callback to the next middleware function
+
+---
+
+### `convertTo720p()`
+- **Description**: Converts the uploaded video to a 720p resolution to reduce file size.
+- **Parameters**:
+  - `req`: Express request object
+  - `res`: Express response object
+  - `next`: Callback to the next middleware function
+
+---
+
+### `handleUpload()`
+- **Description**: Manages the uploaded files and records their metadata into the database.
+- **Parameters**:
+  - `req`: Express request object
+  - `res`: Express response object
+  - `next`: Callback to the next middleware function
+