File uploads hang indefinitely in SDK's uploadTempFile method

[MarianoMolina]

When trying to use image capabilities with the SDK, the uploadTempFile method in FilesNamespace hangs indefinitely. This prevents any functionality that relies on file uploads (like vision model usage) from working.

Steps to reproduce:

1. Set up basic chat completion with vision model
2. Try to process an image URL message:

{
    "role": "user",
    "content": [
        {
            "type": "image_url",
            "image_url": {
                "url": "https://upload.wikimedia.org/wikipedia/commons/thumb/d/d3/Stadtbild_M%C3%BCnchen.jpg/2560px-Stadtbild_M%C3%BCnchen.jpg"
            }
        },
        {
            "type": "text",
            "text": "What city is this?"
        }
    ]
}

Code snippet:

        if (content.type === 'image_url' && content.image_url) {
            Logger.debug('Processing image:', content.image_url.url);
            let fileData: { mimeType: string; data: Uint8Array };

            try {
                if (this.isBase64DataUrl(content.image_url.url)) {
                    fileData = await this.processBase64DataUrl(content.image_url.url);
                } else {
                    fileData = await this.fetchFromUrl(content.image_url.url);
                }
                Logger.debug('Image processed:', fileData.mimeType, 'Size:', fileData.data.length);

                this.validateFileType(fileData.mimeType);
                this.validateFileSize(fileData.data);

                Logger.debug('Starting file upload...');
                const fileName = `image_${Date.now()}.${fileData.mimeType.split('/')[1]}`;
                Logger.debug('Generated filename:', fileName);

                try {
                    const fileHandle = await Promise.race([
                        this.filesNamespace.uploadTempFile(fileName, fileData.data),
                        new Promise((_, reject) =>
                            setTimeout(() => reject(new Error('Upload timeout after 30s')), 30000)
                        )
                    ]) as FileHandle;

                    Logger.debug('Upload successful. File handle:', {
                        identifier: fileHandle.identifier,
                        type: fileHandle.type,
                        size: fileHandle.sizeBytes
                    });

                    return { type: 'file', file: fileHandle };
                } catch (error: unknown) {
                    const errorMessage = error instanceof Error ? error.message : 'Unknown upload error';
                    Logger.error('Upload failed:', errorMessage);
                    throw new FileProcessingError(
                        `Failed to upload file: ${errorMessage}`,
                        'UPLOAD_FAILED'
                    );
                }

            } catch (error) {
                Logger.error('Image processing failed:', error);
                throw error;
            }
        }

The code hangs at:

const fileHandle = await this.filesNamespace.uploadTempFile(
    `image_${Date.now()}.${fileData.mimeType.split('/')[1]}`,
    fileData.data
);

Where data: Uint8Array

Expected behavior:

• File should upload and return a FileHandle
• Chat completion should proceed with the uploaded image

Actual behavior:

• uploadTempFile never resolves or rejects
• Program hangs indefinitely unless manually terminated

Environment:

• LM Studio SDK version: 0.4.2
• LM Studio: 0.3.5 b9
• LMS cli: 0.0.28
• OS: Windows

Other functionality like model loading/unloading works correctly, suggesting this is specific to the file upload implementation. Let me know if you need any additional information.