Regex implementation (yet to be implemented)

args/args.go

@@ -16,8 +16,7 @@ var flagsParsed bool = false;
 
 /* what JSON file to read config values from */
 var confLocation = flag.String("conf", "./config.txt", "Config file to read from")
-/* Returns nil if flags are not parsed yet
-   @return set boolean will be true if argument is not nil */
+/* @return set boolean will be true if argument is not nil */
 func GetConfLocation() (location string, set bool) {
 	if confLocation == nil {return "", false}
 	return *confLocation, true;

conf/conf.go

@@ -1,5 +1,8 @@
 package conf
 
+/* This file contains the Config object and its methods, which handle reading
+   from a config file and matching requests to the whitelist. */
+
 import (
 	"bufio"
 	"errors"
@@ -7,11 +10,14 @@ import (
 	"strings"
 )
 
+// import "fmt"
+
 /* Object to handle what is in a JSON config */
 type Config struct {
 	configData map[string][]string;
 }
 
+/* Opens and reads a file at the path */
 func NewConfig(filePath string) (newConfig *Config, err error) {
 	// Open file
 	file, err := os.Open(filePath)
@@ -34,4 +40,5 @@ func NewConfig(filePath string) (newConfig *Config, err error) {
 	return &Config{configData: newConfigData}, nil;
 }
 
+/* Gets a reference copy to the config data */
 func (config Config) GetConfigData() map[string][]string {return config.configData;}

conf/readme.md

@@ -18,5 +18,5 @@ There is a regex-like behavior to these paths using the `*` and `?` characters.
 
 The `*` character matches to any number of path segments. The `?` character matches to only one segment. Here's some examples:
 
-* `HZJWwB0TAjz6pjAHosII5ofR /+16028675309/*` will allow the bearer token to access any endpoint with the phone number `+16028675309`
+* `HZJWwB0TAjz6pjAHosII5ofR /+16028675309/*` will allow the bearer token to access any endpoint with the phone number `+16028675309`.
 * `HZJWwB0TAjz6pjAHosII5ofR /+16028675309/direct/?/send` will allow the bearer token to send a direct message to anyone on that phone number.

conf/regex.go

@@ -0,0 +1,62 @@
+package conf
+
+/* This file contains regex helper functions for parsing configs  */
+
+import (
+	"strings"
+)
+
+/* Splits and normalises */
+func splitPath(path string) []string {
+	return strings.Split(strings.Trim(path, "/"), "/")
+}
+
+/* Attempts to match a request path to a set of whitelisted paths
+   @return false for anything other than a valid match */
+func match(request string, matchTo []string) bool {
+	requestSplit := splitPath(request)
+	for _, matchToAttempt := range matchTo {
+		matchToAttemptSplit := splitPath(matchToAttempt);
+		if matchSegments(requestSplit, matchToAttemptSplit) {
+			return true;
+		}
+	}
+	
+	return false;
+}
+
+/* Returns false for anything other than a valid match */
+func matchSegments(request []string, matchTo []string) bool {
+	/* This is a recursive function which, at each recursion level, matches the
+	   path segments that are in the front of the request and matchTo lists
+	   It matches identical strings, anything to &, and splits in two when
+	   matching anything to *, to account for consuming or not consuming the *
+	   at the current recursion level. */
+	
+	// Recursion base case for perfect match
+	if len(request) == 0 && len(matchTo) == 0 {return true}
+	// End of path for one but not the other
+	if (len(request) & len(matchTo)) == 0 {return false}
+	
+	// Grab current path segments
+	requestCurrent := request[0];
+	matchToCurrent := matchTo[0];
+	
+	// & character and direct match have the same behavior
+	if (matchToCurrent == "&") || (requestCurrent == matchToCurrent) {
+		return matchSegments(request[1:], matchTo[1:]);
+	}
+	
+	// * character
+	if (matchToCurrent == "*") {
+		// These are split for performance
+		// Usually the * only refers to 1 or 2 things so putting consumption
+		// first is probably a better choice
+		if (matchSegments(request[1:], matchTo[1:])) {return true}
+		if (matchSegments(request[1:], matchTo)) {return true}
+		return false;
+	}
+	
+	// Code will reach here if there's no match for the current segment
+	return false;
+}

main.go

@@ -17,6 +17,7 @@ func main() {
 	if !confLocationSet {log.Default().Print("No config value!"); return;}
 	log.Default().Print("Reading config value from ", configLocation);
 	
+	// Set up config 
 	config, err := conf.NewConfig(configLocation);
 	if err != nil {log.Default().Print("Error reading config: ", err); return;}
 	fmt.Println(config.GetConfigData())