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pythonurllib

Using urljoin to add query-parameter value

I have a prepared URL https://my.comp.com/Online/SendToken?token= that I want to append the parameter value 123 to.

What I have tried so far:

from urllib.parse import urljoin

urljoin('https://my.comp.com/Online/SendToken?token=','123')
# prints 'https://my.comp.com/Online/123'

What I want to get is:

'https://my.comp.com/Online/SendToken?token=123'

I know I can use + to concatenate two strings, but I want to use the urljoin for it.

Solution

  • Issue

    If you only pass a query-parameter value, it will not join them as expected.

    Second argument

    The second argument is interpreted as path, so it needs to be a valid

    • complete path,
    • path segment (may include query-parameter or fragment)
    • query (prefixed with ?
    • fragment (prefixed with #)

    See the docs for urljoin, use the first 2 examples:

    from urllib.parse import urljoin

# the complete query-parameter (question-mark, key, value)
urljoin('https://my.comp.com/Online/SendToken?token=','?token=123')
# 'https://my.comp.com/Online/SendToken?token=123'

# the complete path-segment including query
urljoin('https://my.comp.com/Online/SendToken?token=','SendToken?token=123')
# 'https://my.comp.com/Online/SendToken?token=123'

# a fragment (denoted by hash-symbol) will also work, but not desired
urljoin('https://my.comp.com/Online/SendToken?token=','#123')
# 'https://my.comp.com/Online/SendToken?token=#123'

    See also Python: confusions with urljoin