Fix a few peek command issues

Author: ethanhann

docs-src/queuing.md

@@ -124,17 +124,17 @@ Queued commands can be viewed in JSON which maybe useful for debugging:
 inengine.exe -pInEngine.Core queue:peek --pending --json
 ```  
 
-By default, up to 10 messages will be retrieved, but the number is configurable:
+By default, up to the first 10 messages will be retrieved, but the range is configurable:
 
 ```bash
-inengine.exe -pInEngine.Core queue:peek --pending --limit=100
+inengine.exe -pInEngine.Core queue:peek --pending --to=100
 ```
 
-The a paginated slice of the queue can be retrieved using the offset argument.
+A slice of the queue can be retrieved using the from argument.
 For example, this queue:peek call retrieves the 100-200 queued commands:
 
 ```bash
-inengine.exe -pInEngine.Core queue:peek --pending --limit=100 --offset=100
+inengine.exe -pInEngine.Core queue:peek --pending --from=100 --to=200
 ```
 
 ## Handling Failed Commands

src/InEngine.Core/Queuing/Clients/FileClient.cs

@@ -62,7 +62,7 @@ public bool Consume()
         {
             var fileInfo = new DirectoryInfo(PendingQueuePath)
                 .GetFiles()
-                .OrderByDescending(x => x.LastWriteTimeUtc)
+                .OrderBy(x => x.LastWriteTimeUtc)
                 .FirstOrDefault();
             if (fileInfo == null)
                 return false;
@@ -164,11 +164,18 @@ public List<IMessage> PeekPendingMessages(long from, long to)
 
         public List<IMessage> PeekMessages(string queuePath, long from, long to)
         {
-            return new DirectoryInfo(queuePath)
+            var maxResults = Convert.ToInt32(to + from);
+            var files = new DirectoryInfo(queuePath)
                 .GetFiles()
-                .ToList()
-                .GetRange(Convert.ToInt32(from), Convert.ToInt32(to - from))
-                .Select(x => File.ReadAllText(x.FullName).DeserializeFromJson<IMessage>())
+                .OrderBy(x => x.LastWriteTimeUtc)
+                .ToList();
+
+            if (files.Count() <= maxResults)
+                return files.Select(x => File.ReadAllText(x.FullName).DeserializeFromJson<Message>() as IMessage).ToList();
+
+            return files
+                .GetRange(Convert.ToInt32(from), Convert.ToInt32(to))
+                .Select(x => File.ReadAllText(x.FullName).DeserializeFromJson<Message>() as IMessage)
                 .ToList();
         }
     }

src/InEngine.Core/Queuing/Commands/Peek.cs

@@ -11,11 +11,11 @@ namespace InEngine.Core.Queuing.Commands
 {
     public class Peek : AbstractCommand
     {
-        [Option("offset", DefaultValue = 0, HelpText = "The maximum number of messages to peek.")]
-        public long Offset { get; set; }
+        [Option("from", DefaultValue = 0, HelpText = "The first message to peek at (0-indexed).")]
+        public long From { get; set; }
 
-        [Option("limit", DefaultValue = 10, HelpText = "The maximum number of messages to peek.")]
-        public long Limit { get; set; }
+        [Option("to", DefaultValue = 10, HelpText = "The last message to peek at.")]
+        public long To { get; set; }
 
         [Option("json", HelpText = "View the messages as JSON.")]
         public bool JsonFormat { get; set; }
@@ -34,19 +34,24 @@ public class Peek : AbstractCommand
 
         public override void Run()
         {
+            if (From < 0)
+                throw new ArgumentException("--from cannot be negative");
+            if (To < 0)
+                throw new ArgumentException("--to cannot be negative");
+            if (To < From)
+                throw new ArgumentException("--from cannot be greater than --to");
+            
             if (PendingQueue == false && FailedQueue == false && InProgressQueue == false)
                 throw new CommandFailedException("Must specify at least one queue to peek in. Use -h to see available options.");
             var broker = Queue.Make(UseSecondaryQueue);
-            var from = Offset;
-            var to = Offset + Limit - 1;
             if (PendingQueue) {
-                PrintMessages(broker.PeekPendingMessages(from, to), "Pending");
+                PrintMessages(broker.PeekPendingMessages(From, To), "Pending");
             }
             if (InProgressQueue) {
-                PrintMessages(broker.PeekInProgressMessages(from, to), "In-progress");
+                PrintMessages(broker.PeekInProgressMessages(From, To), "In-progress");
             }
             if (FailedQueue) {
-                PrintMessages(broker.PeekFailedMessages(from, to), "Failed");
+                PrintMessages(broker.PeekFailedMessages(From, To), "Failed");
             }
         }