feat: Support uri format validation

Author: janrose-gcx

CHANGELOG.md

@@ -6,6 +6,10 @@
 
 - `ValidationResult.Valid` was renamed to `ValidationResult.valid`.
 
+### Enhancements
+
+- `uri` format is now validated.
+
 
 ## 0.3.0
 

Sources/JSONSchema.swift

@@ -61,6 +61,7 @@ public struct Schema {
     formats = [
       "ipv4": validateIPv4,
       "ipv6": validateIPv6,
+      "uri": validateURI,
     ]
   }
 

Sources/Validators.swift

@@ -423,3 +423,23 @@ func validateIPv6(_ value:Any) -> ValidationResult {
 
   return .valid
 }
+
+func validateURI(_ value:Any) -> ValidationResult {
+  if let uri = value as? String {
+    // Using the regex from http://blog.dieweltistgarnichtso.net/constructing-a-regular-expression-that-matches-uris
+
+    if let expression = try? NSRegularExpression(pattern: "((?<=\\()[A-Za-z][A-Za-z0-9\\+\\.\\-]*:([A-Za-z0-9\\.\\-_~:/\\?#\\[\\]@!\\$&'\\(\\)\\*\\+,;=]|%[A-Fa-f0-9]{2})+(?=\\)))|([A-Za-z][A-Za-z0-9\\+\\.\\-]*:([A-Za-z0-9\\.\\-_~:/\\?#\\[\\]@!\\$&'\\(\\)\\*\\+,;=]|%[A-Fa-f0-9]{2})+)", options: NSRegularExpression.Options(rawValue: 0)) {
+      let result = expression.matches(in: uri, options: NSRegularExpression.MatchingOptions(rawValue: 0), range: NSMakeRange(0, uri.characters.count))
+      if result.count == 1 {
+        let foundRange = result[0].range
+        if foundRange.location == 0 && foundRange.length == uri.characters.count {
+          return .valid
+        }
+      }
+    }
+
+    return .invalid(["'\(uri)' is not a valid URI."])
+  }
+
+  return .valid
+}