Semver check script

osx-config.hjson

@@ -110,9 +110,10 @@
             {
                 //Past test if the latest version available via `brew cask install java` is installed
                 type: "exact match"
-                command: java -version 2>&1 >/dev/null | grep 'java version'
-                command_pass:
-                    java version "1.8.0_102"
+                #java version "1.8.0_102"
+                command: java -version 2>&1 >/dev/null | grep 'java version' | python ./scripts/semver_check.py --prefix 'java version "' '>=1.8.0_102'
+                command_pass: 1
+                command_fail: 0
                 case_sensitive: false
             }
         ]
@@ -502,10 +503,12 @@
         tests:
         [
             {
-                type: "exact match"
-                command: "openssl version"
-                command_pass: "OpenSSL 1.0.2j  26 Sep 2016"
-                case_sensitive: "false"
+                type: exact match
+                # $ openssl version
+                # OpenSSL 1.0.2j  26 Sep 2016
+                command: openssl version | python ./scripts/semver_check.py --prefix "OpenSSL " ">=1.0.2h"
+                command_pass: 1
+                case_sensitive: false
             }
         ]
         fix:
@@ -1045,9 +1048,12 @@
         [
             {
                 type: "regex match"
-                command: "git --version"
-                command_pass: ".*(command not found|2\\.9\\.3|2\\.\\d\\d+\\.\\d+).*"
-                case_sensitive: "false"
+                # $ git --version
+                # git version 2.10.2
+                command: git --version | python ./scripts/semver_check.py --prefix "git version " ">=2.10.2"
+                command_pass: 1
+                command_fail: 0
+                case_sensitive: false
             }
         ]
         fix:
@@ -1121,18 +1127,18 @@
         tests:
         [
             {
-                type: "regex match"
-                command: "curl --version"
-                command_pass: ".*(command not found|7\\.50\\.1).*"
+                type: regex match
+                command: curl --version | python ./scripts/semver_check.py --prefix "curl " ">=7.51.0"
+                command_pass: 1
+                command_fail: 0
                 case_sensitive: "false"
             }
         ]
         fix:
         {
             command:
-                brew update ; brew install curl ; brew upgrade curl ; python ./scripts/set_path_precedence.py "/usr/local/bin" "/usr/bin"
+                brew update ; brew install curl ; brew upgrade curl ; bash ./scripts/set_curl_latest_path.sh
         }
-        undo: "brew unlink curl"
     },
     {
         description: "FileVault file system encryption is enabled."

scripts/semver_check.py

@@ -0,0 +1,189 @@
+"""Verifies that the output of a command contains a compatible semver string.
+
+Currently this can only support a limited subset of semantic version strings,
+e.g.:
+ * "git version 2.10.2"
+ * "curl 7.50.1 (x86_64-apple-darwin15.6.0) libcurl/7.50.1 SecureTransport zlib/1.2.5"
+ * "java version "1.8.0_102""
+ * "OpenSSL 1.0.2h  3 May 2016"
+
+The script aspires to be fully semver 2.0.0 compliant in the future. See:
+http://semver.org/
+
+The command that is piped to this script via stdin must only return a matching
+string once; otherwise, the first string that looks like a semver string using
+the optional prefix string will be compared and subsequent ones will be ignored.
+
+Usage:
+
+    $ some command | python semver_check.py [--prefix "prefix string"] "semver pattern"
+
+Examples:
+
+    $ git --version | python semver_check.py --prefix "git version " ">=2.10.1"
+    1
+
+    $ git --version | python semver_check.py ">=2.10.3"
+    0
+"""
+import sys
+import os
+import re
+
+ENABLE_DEBUG_PRINT = False
+SEMVER_PERMITTED_REGEX = r'(\>\=)?(\d+\w*\.\d+\w*\.\d+\w*)'
+SEMVER_SEARCH_REGEX = r"(\d+\w*\.\d+\w*\.\d+\w*)"
+
+def print_usage(err_msg=None):
+    """Print usage string and exit"""
+    if err_msg is not None:
+        print "Error: %s" % err_msg
+    print("Usage: $ some command | python semver_check.py [--prefix "
+          "\"prefix string\"] \"semver pattern\"")
+    sys.exit()
+
+
+def _get_number_part(version_piece):
+    matches = re.search(r'(\d+)', version_piece)
+    if matches is None:
+        raise ValueError
+    else:
+        return int(matches.groups(1)[0])
+
+
+def _get_alpha_part(version_piece):
+    """Returns the alphabetical portion of version piece with exception*.
+
+    Exception*: If the alphabetical portion matches an underscore followed by
+    digits, then this will instead be cast to int and returned to ensure proper
+    comparison by the caller. This accounts for version strings such as those
+    used by Java, e.g. version "1.0.0_1" is less than "1.0.0_10"
+
+    Returns: str or int
+    """
+    matches = re.search(r'\d+(\w+)', version_piece)
+    if matches is None:
+        return ''
+    else:
+        alpha = matches.groups(1)[0]
+        matches2 = re.search(r'_(\d+)', alpha)
+        if matches2 is not None:
+            return int(matches2.groups(1)[0])
+        else:
+            return alpha
+
+def does_str_match_semver(subject_str, semver_str, gr_or_eq=False):
+    """Returns True if subject matches semver.
+    Args:
+        subject_str (str): The subject we're scrutinizing.
+        semver_str (str): The semver we're testing against the subject.
+        gr_pr_eq (bool): If set, the subject can be equal to or greater than
+            the specified semver.
+    """
+    dprint("Comparing subject '%s' with semver '%s'" % (subject_str, semver_str))
+    subject_pieces = subject_str.split('.')
+    semver_pieces = semver_str.split('.')
+
+    for cur_index, subject_piece in enumerate(subject_pieces):
+        semver_piece = semver_pieces[cur_index]
+
+        subject_numbers = _get_number_part(subject_piece)
+        semver_numbers = _get_number_part(semver_piece)
+
+        subject_alpha = _get_alpha_part(subject_piece)
+        semver_alpha = _get_alpha_part(semver_piece)
+
+        if gr_or_eq:
+            if (subject_numbers > semver_numbers and
+                    subject_alpha >= semver_alpha):
+                #Strictly greater version, no need to check subsequent pieces
+                return True
+
+            elif (subject_numbers == semver_numbers and
+                  subject_alpha > semver_alpha):
+                #Strictly greater version, no need to check subsequent pieces
+                return True
+
+            elif subject_numbers < semver_numbers:
+                return False
+
+            elif (subject_numbers == semver_numbers and
+                  subject_alpha < semver_alpha):
+                return False
+
+        else:
+            if (subject_numbers != semver_numbers or
+                    subject_alpha != semver_alpha):
+                return False
+
+    return True
+
+
+def get_stdin():
+    """Returns stdin or exits if not available.
+
+    See:
+    http://stackoverflow.com/questions/13143218/how-do-i-avoid-processing-an-empty-stdin-with-python
+    """
+    if os.fstat(sys.stdin.fileno()).st_size > 0:
+        return sys.stdin.readlines()
+    else:
+        print_usage("No command output provided via stdin.")
+
+
+def get_args():
+    """Get command-line arguments or exit with usage string."""
+    args = {}
+    if len(sys.argv) == 2:
+        args['semver'] = sys.argv[1]
+    elif len(sys.argv) == 4:
+        args['prefix'] = sys.argv[2]
+        args['semver'] = sys.argv[3]
+    else:
+        print_usage("Wrong number of command-line arguments.")
+
+    dprint(args)
+
+    return args
+
+
+def is_match(stdin=None, args=None):
+    """Returns as bool whether stdin is a match for specified semver."""
+    if stdin is None:
+        stdin = get_stdin()
+    if args is None:
+        args = get_args()
+
+    dprint("stdin='%s' type='%s'" % (str(stdin), str(type(stdin))))
+
+    semver_matches = re.match(SEMVER_PERMITTED_REGEX, args['semver'])
+    gr_or_eq = False
+    if semver_matches is None:
+        dprint("Semver: '%s'" % args['semver'])
+        print_usage("Invalid semver pattern.")
+    else:
+        gr_or_eq = (semver_matches.group(1) != None)
+
+    #find a semver-looking string in stdin
+    search_regex = SEMVER_SEARCH_REGEX
+    if 'prefix' in args:
+        search_regex = r'%s%s' % (re.escape(args['prefix']), search_regex)
+    dprint("search_regex = '%s'" % search_regex)
+
+    for index, line in enumerate(stdin):
+        matches = re.search(search_regex, line)
+        if matches is not None:
+            dprint("Line #%d matches the search_regex: '%s'" % (index + 1, line))
+            subject_str = matches.group(1)
+            return does_str_match_semver(subject_str, args['semver'], gr_or_eq)
+
+    #Never found the string we were looking for
+    return False
+
+def dprint(data):
+    """Print debug information."""
+    if ENABLE_DEBUG_PRINT:
+        print "DEBUG: %s" % str(data)
+
+if __name__ == '__main__':
+    print "1" if is_match() else "0"

scripts/set_curl_latest_path.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+# Description: Sets the position of the most recent version of curl in the
+# PATH environment variable
+
+# set working directory to the one containing this script so it can find other
+# scripts.
+cd "$(dirname "$0")"
+
+CURL_LATEST_PATH=$(find /usr/local/Cellar/curl -name "bin" -maxdepth 2 -type d | sort -nr | head -n 1)
+
+if [ -n "$CURL_LATEST_PATH" ] ; then
+    echo "Attempting to fix..."
+    python ./set_path_precedence.py "$CURL_LATEST_PATH" "/usr/bin"
+else
+    echo "Could not find Homebrew installation of curl."
+fi