The file upload answer component - our recommendations

Occasionally, you may wish to include a file upload answer component in your online survey, which allows your respondents to upload a file to support their response. This is possible in Citizen Space, but we'd advise to use these sparingly, if at all. Our recommendation is to instead request supporting files over email.

There are a few reasons for this, which we've outlined here:

• As this component will collect offline files, any attachment uploaded to it must be downloaded to your computer in order for you to analyse its contents offline. This can add a big burden on your analysis process.
• Adding lots of these components runs the risk of using up a lot of the memory in your site server and could therefore affect the performance of your site if these are all being used by your respondents. For example, if you have 10 of these in your online survey, it will be the equivalent of each respondent sending you ten big files over email, but this would be happening simultaneously across multiple responses. In some cases this has been into the hundreds of respondents at once = thousands of files being uploaded to your server all at the same time. While we do everything we can to sustain your site performance, it is impossible for us to protect against this kind of scenario where lots of chunky files are involved.
• If you offer people the option to upload files, you have to accept the risk that people could upload ones containing malware or other corrupted files, so you must have malware and anti-virus checking on your computer (it is highly likely you do due to other files you'll receive over email and so on). Citizen Space servers do not touch any files uploaded and this protects your Citizen Space site, but we have no control over downloads to your local machine.
• A more process-related risk is that someone may upload a file type that you cannot open with the software you have on your computer (i.e. it might not be a PDF or Word doc, it might be something more unusual), so you wouldn't be able to open and analyse it.

Our advice and available settings

Disabling the file upload component site-wide

It is possible for us to turn the file upload answer component fully off on your site, so that the file upload component cannot be used as an answer component. If you would like this disabled, please get in touch and we will disable it. Having this answer component turned off is the default setting on newly deployed sites and our recommended approach.

Use only one or two file upload components per survey at most

If you do have this answer component enabled, for all the reasons outlined above, our advice is to only use at most one or two in an online survey. If you choose to add more, this would go above what we can support if it were to cause performance issues.

Restricting the size of files able to be uploaded

To try and save your site from being overloaded by attachments uploaded with responses, we apply a maximum 25MB default limit on the size of file Citizen Space will accept in each of these components, which is a very large file per component (for example, this is the maximum size most emails can be). This individual file size limit can be reduced site-wide. Let us know if you would like us to reduce this.