Added additional NCC information and diff image to urlwatcher.sh

Added /diff command to show the diff image and extended information in Telegram
Added error handling for non-JFBotError errors

Author: iComputerfreak

NotifierBot/Sources/Notifier/Commands/Command.swift

@@ -48,6 +48,12 @@ extension Command {
                 try self.run(update: update, context: context)
             } catch let error as JFBotError {
                 JFErrorHandler.shared.handle(error, update: update)
+            } catch let error {
+                // Other errors
+                if let chatID = update.message?.chat.id {
+                    _ = try? bot.sendMessage("An unknown error occurred while executing this command. Please check the console for more information.", to: chatID)
+                }
+                print("Error: \(error)")
             }
         })
     }

NotifierBot/Sources/Notifier/Commands/DiffCommand.swift

@@ -0,0 +1,37 @@
+//
+//  DiffCommand.swift
+//  
+//
+//  Created by Jonas Frey on 04.05.21.
+//
+
+import Foundation
+import Telegrammer
+
+struct DiffCommand: Command {
+    
+    let name = "Diff"
+    let commands = ["/diff"]
+    let syntax = "/diff <name>"
+    let description = "Returns a visual representation of the changed parts of the image."
+    let permission = BotPermission.mod
+    
+    func run(update: Update, context: BotContext?) throws {
+        let chatID = try update.chatID()
+        let args = try update.args()
+        guard args.count > 0 else {
+            try showUsage(chatID)
+            return
+        }
+        let name = args.joined(separator: " ")
+        // Check if an entry with this name exists
+        let config = try ConfigParser.getConfig()
+        guard config.contains(where: { $0.name.lowercased() == name.lowercased() && $0.chatID == chatID }) else {
+            try bot.sendMessage("There is no entry with the name '\(name)'", to: chatID)
+            return
+        }
+        // Send the diff file and the contents of the ncc file
+        let nccInfo = try String(contentsOfFile: "\(mainDirectory!)/images/\(name)/\(nccFile)")
+        JFUtils.sendImage(path: "\(mainDirectory!)/images/\(name)/\(diffFile)", chatID: chatID, text: nccInfo)
+    }
+}

NotifierBot/Sources/Notifier/JFUtils.swift

@@ -39,16 +39,20 @@ struct JFUtils {
         }
     }
 
-    static func sendFile(path: String, chatID: Int64) {
-        sendImageOrFile(path: path, chatID: chatID, isFile: true)
+    static func sendFile(path: String, chatID: Int64, text: String? = nil) {
+        sendImageOrFile(path: path, chatID: chatID, isFile: true, text: text)
     }
 
-    static func sendImage(path: String, chatID: Int64) {
-        sendImageOrFile(path: path, chatID: chatID, isFile: false)
+    static func sendImage(path: String, chatID: Int64, text: String? = nil) {
+        sendImageOrFile(path: path, chatID: chatID, isFile: false, text: text)
     }
 
-    static private func sendImageOrFile(path: String, chatID: Int64, isFile: Bool) {
-        shell("\(kTelegramScript) -t \(token!) -c \(chatID) -\(isFile ? "f" : "i") \(path)")
+    static private func sendImageOrFile(path: String, chatID: Int64, isFile: Bool, text: String? = nil) {
+        var command = "\(kTelegramScript) -t \(token!) -c \(chatID) -\(isFile ? "f" : "i") \(path)"
+        if let text = text {
+            command += " \(text)"
+        }
+        shell(command)
     }
 
     static func entryList(_ entries: [URLEntry], listArea: Bool, listURLs: Bool, listAll: Bool = false) -> String {

NotifierBot/Sources/Notifier/main.swift

@@ -34,16 +34,19 @@ let kPythonPath = "/usr/bin/python3"
 // The convert binary from the imagemagick package
 let kConvertPath = "/usr/bin/convert"
 
-// Disable Notifications by default
-let defaultParameters = ["disable_notification": true, "disable_web_page_preview": true]
+// The file containing the detailed NCC information, produced by the urlwatcher.sh script
+let nccFile = "ncc"
+// The diff image
+let diffFile = "diff.png"
 
 /* END BOT SETTINGS */
 
 // An ordered list of all commands to register
 // The order defines the order of commands in the /help list
 let allCommands: [Command] = [
-    HelpCommand(), AddCommand(), RemoveCommand(), ListCommand(), ListURLsCommand(), ListAllCommand(), UpdateCommand(),
-    CheckCommand(), FetchCommand(), FetchURLCommand(), GetPermissionsCommand(), SetPermissionsCommand(), MyIDCommand()
+    HelpCommand(), ListCommand(), ListURLsCommand(), MyIDCommand(),
+    AddCommand(), RemoveCommand(), UpdateCommand(), FetchCommand(), FetchURLCommand(), DiffCommand(),
+    ListAllCommand(), CheckCommand(), GetPermissionsCommand(), SetPermissionsCommand()
 ]
 
 var token: String!

urlwatcher/urlwatcher.sh

@@ -14,6 +14,10 @@ SCREENSHOT_SCRIPT="$(pwd)/../tools/screenshot.sh"
 TELEGRAM_BOT_TOKEN=$(head -n 1 ../BOT_TOKEN)
 # The threshold when to consider two images matching. If two images have a normalized cross correllation >= this value, they are considered identical
 NCC_THRESHOLD="0.99"
+# The file where the diff image is saved to
+DIFF_FILE="diff.png"
+# The file where the NCC value is saved to
+NCC_FILE="ncc"
 
 # Set the PATH variable for the python script below, so it finds the geckodriver executable when executed from cron
 PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
@@ -31,8 +35,9 @@ fi
 function reportChange {
     local NAME="$1"
     local IMAGE="$2"
+    local NCC="$3"
     "$TELEGRAM_SCRIPT" -t "$TELEGRAM_BOT_TOKEN" -c "$CHAT_ID" \
-        -i $IMAGE "$NAME has changed"
+        -i $IMAGE "$NAME has changed. NCC: $NCC"
 }
 
 function reportError {
@@ -101,7 +106,7 @@ function screenshotsMatch {
     local IMAGE_LATEST="$2"
 
     # Calculate the normalized cross correllation between both images
-    NCC=$(compare -metric NCC "$IMAGE_OLD" "$IMAGE_LATEST")
+    NCC=$(compare -metric NCC "$IMAGE_OLD" "$IMAGE_LATEST" "$DIFF_FILE")
 
     if [ "NCC" -lt "$NCC_THRESHOLD" ]; then
         # The screenshots are not identical
@@ -126,9 +131,13 @@ function screenshotsMatch {
 
         # Compare the two cropped screenshots again
         # Calculate the normalized cross correllation between both images
-        NCC=$(compare -metric NCC "$IMAGE_OLD" "$IMAGE_LATEST")
+        NCC=$(compare -metric NCC "$IMAGE_OLD" "$IMAGE_LATEST" "$DIFF_FILE")
 
         if [ "NCC" -lt "$NCC_THRESHOLD" ]; then
+            # The screenshots do not match. The website has changed
+            # Write detailed NCC information to a file (and don't overwrite the diff file)
+            compare -verbose -metric NCC "$IMAGE_OLD" "$IMAGE_LATEST" /dev/null > "$NCC_FILE"
+
             # Return false, as the screenshots do not match
             # In bash: 1 == false
             return 1
@@ -224,7 +233,7 @@ while IFS='' read -r line || [ -n "${line}" ]; do
 
     # If there was a change
     if ! screenshotsMatch "old.png" "latest.png"; then
-        reportChange "$NAME" "latest.png"
+        reportChange "$NAME" "latest.png" $(cat "$NCC_FILE")
     fi
 
     # After successfully checking for changes (either no change, or change notified)