Download files and extract their content to text file

I have about 9000 urls for files (pdf, doc, docx)
I want to extract their content to a one text file.
I want each file to be in a one line in the form:
{"file_url": url1, "file_content": content1 }
{"file_url": url2, "file_content": content2 }
{"file_url": url3, "file_content": content3 }
...
{"file_url": url9000, "file_content": content9000 }