Comparing pdf documents

At work, we generate PDF receipt documents, and we wanted to write a unit test to compare PDF documents to verify its generated correctly.
List of programs that can compare pdfs

1. diff-pdf = decided on this as its free, multi platform, works and easy to use
2. pdftotext = free, multi platform but requires extra step of converting pdf to text
3. diffpdf = paid software

Installing diff-pdf on mac (from github readme)

$ brew install diff-pdf

Installing diff-pdf on alpine (first time)

# install compilation tools 
$ apk add make autoconf automake g++ gawk  

# install required libraries 
$ apk add glib-dev poppler-dev poppler-utils wxgtk-dev 

# get codebase to generate binary 
$ git clone https://github.com/vslavik/diff-pdf.git 
$ cd diff-pdf 

# generate configure script 
$ ./bootstrap 

# generate makefile 
$ ./configure 

# generate binary (diff-pdf) 
$ make

List of research sites: stackoverflow, ask ubuntu