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Your LimeSurvey version: 5.6.68
Own server or LimeSurvey hosting:
Survey theme/template: Custom
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Hi there,

I want to create a custom question theme that is built on top of the long free text theme. What I want the theme to do is when the user starts to type in an address I want a list of suggestions to appear. The api I am wanting to use is:  www.canadapost-postescanada.ca/ac/

The issue I am running into is figuring out how to securly pass the api key so that I can fetch the results from the api. What would be the best method to do this?

Thanks!

I think that's a question for Canada Post. There is nothing odd about LimeSurvey, it is a web form.