Return 500 status when an exception is caught in middleware #469
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This was referenced May 26, 2020
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serene
requested changes
Jun 8, 2020
lib/pdfkit/middleware.rb
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| # Do not cache PDFs | ||
| headers.delete('ETag') | ||
| headers.delete('Cache-Control') | ||
| begin |
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I don't think this begin is necessary. We can just catch exceptions in the whole method.
Also, since we are returning an error, can we put the error in the body?
Can we catch just StandardError as well?
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Thanks for the review @serene, I've amended as suggested.
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@serene without begin the middleware catches the exceptions on the @app.call() above, so it will try to handle exceptions outside of the middleware.
This causes the headers to be nil when exception is triggered, which in turn crashes other middleware down the stack.
If an error occurs in the middleware we should reflect that in the response status. A real life example of this was adding compression middleware before PDF middleware which resulted in an exception, tests for a successful response status still passed.
serene
approved these changes
Jun 8, 2020
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If an error occurs in the middleware we should reflect that in the response status instead of echoing the success of the unmodified response.
This will help with response status test assertions. We recently had middleware misconfiguration issues which were not caught by tests expecting a 200 response.