Indeed, a lifetime of pain if you become a programmer.
I addressed your question because it was predicated by the avoidance of a 3rd party solution. If the requirement is to own the integration approach entirely, your solution is only possible with custom code, and a fair bit of it.
Realistically, you will need about a year of study and practice to become proficient in all the SDKs and language constructs I referenced above. You might be able to plow through in a few weeks to get something working, but this would likely be a very minimal solution.
One alternative is Import.io, yes a third party system, but it might be useful to gather the data you want.