upload_max_output_body_len
The upload_max_output_body_len directive sets the maximum size of the output body generated from uploaded files in NGINX.
Description
The upload_max_output_body_len directive is part of the NGINX module designed for handling file uploads. This directive allows you to specify the maximum allowed size of the body of the response generated after processing uploaded files. When the generated output exceeds the specified limit, NGINX will abort the response, returning an appropriate error message to the client. This is crucial for preventing excessive memory usage and managing bandwidth, particularly in scenarios where large files could be uploaded and processed, resulting in large output responses that the server cannot handle efficiently.
The directive can be set in various contexts, including http, server, location, and conditional contexts like if within a location or limit_except. This flexibility allows you to enforce different limits for different paths or server blocks within the same NGINX configuration. The directive accepts a single argument, which is expected to be size specified in bytes, kilobytes (k), or megabytes (m). When specifying the size, it's important to ensure that it aligns with the expected output of your application's processing logic to avoid unnecessary errors during runtime.
Config Example
location /upload {
upload_pass /process_upload;
upload_max_output_body_len 10m;
}Ensure that the specified value is sufficient for expected output; otherwise, NGINX will return an error.
The directive applies primarily to processed output; it may not limit raw upload body size.
Overly strict limits may hinder legitimate file upload operations and responses.