Add some functions to tear first pages from a PDF

libbmc/papers/tearpages.py

@@ -0,0 +1,45 @@
+"""
+This file contains the necessary functions to determine whether we should tear
+the first page from a PDF file, and actually tear it.
+"""
+import tearpages
+
+
+# List of bad publishers which adds an extra useless first page, which can be
+# teared. Please, submit a PR to include new ones which I may not be aware of!
+BAD_PUBLISHERS = [
+    "IOP"
+]
+
+
+def tearpage_needed(bibtex):
+    """
+    Check whether a given paper needs the first page to be teared or not.
+
+    :params bibtex: The bibtex entry associated to the paper, to guess \
+            whether tearing is needed.
+    :returns: A boolean indicating whether first page should be teared or not.
+    """
+    # For each bad publisher, look for it in the publisher bibtex entry
+    has_bad_publisher = [p in bibtex.get("publisher", [])
+                         for p in BAD_PUBLISHERS]
+    # Return True iff there is at least one bad publisher
+    return (True in has_bad_publisher)
+
+
+def tearpage(filename, bibtex=None):
+    """
+    Tear the first page of the file if needed.
+
+    :params filename: Path to the file to handle.
+    :params bibtex: BibTeX dict associated to this file, as the one given by \
+            ``bibtexparser``.
+    :returns: A boolean indicating whether the file has been teared or not. \
+            Side effect is tearing the first page from the file.
+    """
+    if bibtex is not None and tearpage_needed(bibtex):
+        # If tearing is needed, do it and return True
+        tearpages.tearpage(filename)
+        return True
+    # Else, simply return False
+    return False