add pdf merger tutorial

Author: x4nth055

Diff for: README.md

@@ -158,5 +158,6 @@ This is a repository of all the tutorials of [The Python Code](https://www.thepy
     - [How to Convert PDF to Images in Python](https://www.thepythoncode.com/article/convert-pdf-files-to-images-in-python). ([code](handling-pdf-files/convert-pdf-to-image))
     - [How to Compress PDF Files in Python](https://www.thepythoncode.com/article/compress-pdf-files-in-python). ([code](handling-pdf-files/pdf-compressor))
     - [How to Encrypt and Decrypt PDF Files in Python](https://www.thepythoncode.com/article/encrypt-pdf-files-in-python). ([code](handling-pdf-files/encrypt-pdf))
+    - [How to Merge PDF Files in Python](https://www.thepythoncode.com/article/merge-pdf-files-in-python). ([code](handling-pdf-files/pdf-merger))
 
 For any feedback, please consider pulling requests.

Diff for: handling-pdf-files/pdf-merger/README.md

@@ -0,0 +1,28 @@
+# [How to Merge PDF Files in Python](https://www.thepythoncode.com/article/merge-pdf-files-in-python)
+To run this:
+- `pip3 install -r requirements.txt`
+-
+    ```
+    $ python pdf_merger.py --help
+    ```
+    **Output:**
+    ```
+    usage: pdf_merger.py [-h] -i [INPUT_FILES [INPUT_FILES ...]] [-p [PAGE_RANGE [PAGE_RANGE ...]]] -o OUTPUT_FILE [-b BOOKMARK]
+
+    Available Options
+
+    optional arguments:
+    -h, --help            show this help message and exit
+    -i [INPUT_FILES [INPUT_FILES ...]], --input_files [INPUT_FILES [INPUT_FILES ...]]
+                            Enter the path of the files to process
+    -p [PAGE_RANGE [PAGE_RANGE ...]], --page_range [PAGE_RANGE [PAGE_RANGE ...]]
+                            Enter the pages to consider e.g.: (0,2) -> First 2 pages
+    -o OUTPUT_FILE, --output_file OUTPUT_FILE
+                            Enter a valid output file
+    -b BOOKMARK, --bookmark BOOKMARK
+                            Bookmark resulting file
+    ```
+- To merge `bert-paper.pdf` with `letter.pdf` into a new `combined.pdf`:
+    ```
+    $ python pdf_merger.py -i bert-paper.pdf,letter.pdf -o combined.pdf
+    ```

Diff for: handling-pdf-files/pdf-merger/bert-paper.pdf

@@ -0,0 +1,58 @@
+# Import Libraries
+from PyPDF4 import PdfFileMerger
+import os
+import argparse
+
+
+def merge_pdfs(input_files: list, page_range: tuple, output_file: str, bookmark: bool = True):
+    """
+    Merge a list of PDF files and save the combined result into the `output_file`.
+    `page_range` to select a range of pages (behaving like Python's range() function) from the input files
+        e.g (0,2) -> First 2 pages 
+        e.g (0,6,2) -> pages 1,3,5
+    bookmark -> add bookmarks to the output file to navigate directly to the input file section within the output file.
+    """
+    # strict = False -> To ignore PdfReadError - Illegal Character error
+    merger = PdfFileMerger(strict=False)
+    for input_file in input_files:
+        bookmark_name = os.path.splitext(os.path.basename(input_file))[0] if bookmark else None
+        # pages To control which pages are appended from a particular file.
+        merger.append(fileobj=open(input_file, 'rb'), pages=page_range, bookmark=bookmark_name)
+    # Insert the pdf at specific page
+    merger.write(fileobj=open(output_file, 'wb'))
+    merger.close()
+
+
+def parse_args():
+    """Get user command line parameters"""
+    parser = argparse.ArgumentParser(description="Available Options")
+    parser.add_argument('-i', '--input_files', dest='input_files', nargs='*',
+                        type=str, required=True, help="Enter the path of the files to process")
+    parser.add_argument('-p', '--page_range', dest='page_range', nargs='*',
+                        help="Enter the pages to consider e.g.: (0,2) -> First 2 pages")
+    parser.add_argument('-o', '--output_file', dest='output_file',
+                        required=True, type=str, help="Enter a valid output file")
+    parser.add_argument('-b', '--bookmark', dest='bookmark', default=True, type=lambda x: (
+        str(x).lower() in ['true', '1', 'yes']), help="Bookmark resulting file")
+    # To Parse The Command Line Arguments
+    args = vars(parser.parse_args())
+    # To Display The Command Line Arguments
+    print("## Command Arguments #################################################")
+    print("\n".join("{}:{}".format(i, j) for i, j in args.items()))
+    print("######################################################################")
+    return args
+
+
+if __name__ == "__main__":
+    # Parsing command line arguments entered by user
+    args = parse_args()
+    # convert a single str to a list
+    input_files = [str(x) for x in args['input_files'][0].split(',')]
+    page_range = None
+    if args['page_range']:
+        page_range = tuple(int(x) for x in args['page_range'][0].split(','))
+    # call the main function
+    merge_pdfs(
+        input_files=input_files, page_range=page_range, 
+        output_file=args['output_file'], bookmark=args['bookmark']
+    )

Diff for: handling-pdf-files/pdf-merger/letter.pdf

@@ -0,0 +1 @@
+PyPDF4==1.27.0