Added code to check links, currently only reports links that are invalid

.github/workflows/check-links.yaml

@@ -0,0 +1,19 @@
+name: 'Check Links'
+on:
+  push:
+  pull_request:
+
+jobs:
+  link_check:
+    name: 'Link Check'
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Link Check
+        env:
+          LINK_IGNORE_LIST: https://www.sciencedirect.com,https://portlandpress.com
+        run: |
+          python3 .github/workflows/check_links.py

.github/workflows/check_links.py

@@ -0,0 +1,159 @@
+import http.client
+import urllib.request, urllib.error
+import os
+import sys
+import re
+
+
+
+# set some default variables
+remove_characters = ['**', '\\n']
+
+# text that tends to be at the end of the url that we need truncate everything past them
+end_characters = [')',",","'",'`',"\"",'</a>','</div>',"\\",">","]"]
+
+big_regex = re.compile('|'.join(map(re.escape, remove_characters)))
+
+# if there are any URLs to ignore add here
+link_ignore_list = []
+link_ignore_list_env = os.getenv("LINK_IGNORE_LIST")
+if link_ignore_list_env and len(link_ignore_list_env) > 0:
+    link_ignore_list = link_ignore_list_env.split(',')
+
+print_valid = os.getenv("print_valid_links") is not None
+
+# If we are given a directory then use it, otherwise assume path is current directory
+path = "."
+if len(sys.argv) >1  and os.path.exists(sys.argv[1]):
+    path = sys.argv[1]
+
+# directory environment overrides the system arguments and default.
+directory_env = os.getenv("directory")
+if directory_env and len(directory_env) > 0:
+    path = directory_env
+
+# list which stores all links to check
+links_to_check = []
+link_file_map = {}
+# Get the response code of the url to see if it exists
+def getResponseCode(url):
+    content = None
+    try:
+        req = urllib.request.Request(url,
+                                     headers={'User-Agent': 'Mozilla/5.0'})
+        conn = urllib.request.urlopen(req)
+        # Only get HTML if we have a potential anchor link
+        if "#" in url and "pdf" not in url:
+            content = conn.read().decode("utf-8")
+    except urllib.error.HTTPError as e:
+        return [e.code, content]
+    except urllib.error.URLError as e:
+        return [404, content]
+    except http.client.InvalidURL:
+        return [200, content]
+    return [conn.getcode(), content]
+
+def clean_link(link):
+    if link.endswith("."):
+        link = link[:link.rfind(".")]
+    if link.endswith("'"):
+        link = link[:link.rfind("'")]
+    if link.endswith("\""):
+        link = link[:link.rfind("\"")]
+    link_stripped = big_regex.sub("", link.strip())
+    for end_c in end_characters:
+        end_index = link_stripped.find(end_c)
+        if end_index != -1:
+            link_stripped = link_stripped[:end_index]
+    return link_stripped
+
+def add_link(loc,link):
+    # this is a command being ran so difficult to validate in this script, skip it
+    if '$(uname' in link:
+        return False
+
+    # get just from the http portion if there was more in from of the string we grabbed
+    link = link[link.find("http"):]
+
+    # if there is a period at the end, truncate to that period. Other periods may be valid
+    # strip various characters that may be in the string
+    link_stripped = clean_link(link)
+    while link_stripped != link:
+        link = link_stripped
+        link_stripped = clean_link(link)
+
+    # add link to be checked
+    links_to_check.append(link_stripped)
+
+    # store where the link is so we can fix it
+    link_file_map[link_stripped] = loc
+def check_link(link):
+    # try and get the url, if its 404 or 500 then its invalid, let us know and trigger the error flag
+    code = getResponseCode(link)
+    loc =link_file_map[link]
+    if code[0] in [404, 403, 500]:
+
+        # If the link failed, but we are ignoring it then just mention that
+        for ignored_link in link_ignore_list:
+            if ignored_link in link:
+                print(
+                    loc + ", " + link + ", Ignored")
+                return False
+
+        # print(file+" Code:"+str(code[0])+" Line "+str(line_num)+"("+str(char)+"):"+item_stripped)
+        print(
+            loc + ", " + link + ", Failed")
+        return True
+
+    # check for missing anchors
+    elif "#" in link and \
+        code[1] is not None \
+        and 'href=\"' + link[link.find("#"):] + '\"' not in \
+        code[1]:
+        print(
+            loc + ", " + link + ", Failed - Anchor")
+    # print(file + " Missing Anchor Line " + str(
+    #     line_num) + "(" + str(
+    #     char) + "):" + item_stripped)
+    elif print_valid:
+        print(
+            loc + ", " + link + ", Valid")
+    return True
+
+
+if __name__ == "__main__":
+    err = 0
+    print("Directory is "+path)
+    # Loop through all files in path
+    for root, dirs, files in os.walk(path):
+        for file in files:
+            #  only read file that match template ( txt, md or python notebook)
+            if file.endswith(".md") or file.endswith(".txt") or file.endswith(
+                ".ipynb"):
+
+                # get content and separate into lines and then separate by spaces
+                raw_content = open(os.path.join(root, file), "r").read()
+                content = raw_content.split("\n")
+                content = [x.split(" ") for x in content]
+                loc = os.path.join(root, file)
+                # have an incrementer for line number later export
+                for line in content:
+                    for item in line:
+
+                        if "https://" in item or "http://" in item:
+                            if "](" in item:
+                                add_link(loc,item[item.find("]"):])
+                                # if we get any error  then add it
+                                if item[item.find("("):] == item[item.find("]"):]:
+                                    continue
+                                add_link(loc,item[item.find("("):])
+                            else:
+                                add_link(loc,item)
+
+    for link in set(links_to_check):
+        # if we get any error  then add to err variable
+        err = check_link(link) + err
+    # if the error is > 1 then set it to 1 to error as 1
+    if err > 1:
+        err = 1
+    exit(err)