Show empty fields

README.md

@@ -216,6 +216,7 @@ feeds:
 ### Example Configuration File
 
 ```yaml
+showEmptyFields: true
 feeds:
   - name: "application-1-logs"
     commands:
@@ -229,6 +230,7 @@ feeds:
       - "DEBUG"
     excludeFields:
       - "thread_name"
+    showEmptyFields: false
   - name: "application-2-logs"
     commands:
       - cat log2.txt
@@ -288,6 +290,12 @@ json-log-viewer --config-file json-log-viewer.yml
   json-log-viewer --timestamp-field time
   ```
 
+- **--show-empty-fields**: Display fields with empty values (null, empty strings, etc.) in output.
+  ```bash
+  cat log.txt | json-log-viewer --show-empty-fields
+  ```
+
+
 #### Field Name Options
 
 You can override the default field names to work with non-standard log formats:

frontend-laminar/src/main/scala/ru/d10xa/jsonlogviewer/ViewElement.scala

@@ -26,6 +26,7 @@ object ViewElement {
 
   def makeConfigYamlForInlineInput(string: String, config: Config): ConfigYaml =
     ConfigYaml(
+      showEmptyFields = None,
       fieldNames = None,
       feeds = Some(
         List(
@@ -38,7 +39,8 @@ object ViewElement {
             rawInclude = None,
             rawExclude = None,
             excludeFields = None,
-            fieldNames = None
+            fieldNames = None,
+            showEmptyFields = None
           )
         )
       )

json-log-viewer/jvm/src/main/scala/ru/d10xa/jsonlogviewer/decline/yaml/ConfigYamlLoaderImpl.scala

@@ -164,6 +164,22 @@ class ConfigYamlLoaderImpl extends ConfigYamlLoader {
       case None => Validated.valid(None)
     }
 
+  private def parseOptionalBoolean(
+    fields: Map[String, Json],
+    fieldName: String
+  ): ValidatedNel[String, Option[Boolean]] =
+    fields.get(fieldName) match {
+      case Some(jsonValue) =>
+        jsonValue
+          .as[Boolean]
+          .leftMap(_ =>
+            s"Invalid '$fieldName' field format, should be a boolean"
+          )
+          .toValidatedNel
+          .map(Some(_))
+      case None => Validated.valid(None)
+    }
+
   private def parseFeed(feedJson: Json): ValidatedNel[String, Feed] =
     feedJson.asObject.map(_.toMap) match {
       case None => Validated.invalidNel("Feed entry is not a valid JSON object")
@@ -177,7 +193,7 @@ class ConfigYamlLoaderImpl extends ConfigYamlLoader {
           parseOptionalString(feedFields, "inlineInput")
         val filterValidated = parseOptionalQueryAST(feedFields, "filter")
         val formatInValidated
-          : Validated[NonEmptyList[String], Option[FormatIn]] =
+        : Validated[NonEmptyList[String], Option[FormatIn]] =
           parseOptionalFormatIn(feedFields, "formatIn")
         val fieldNamesValidated =
           parseOptionalFieldNames(feedFields, "fieldNames")
@@ -190,6 +206,9 @@ class ConfigYamlLoaderImpl extends ConfigYamlLoader {
             feedFields,
             "excludeFields"
           )
+        val showEmptyFieldsValidated =
+          parseOptionalBoolean(feedFields, "showEmptyFields")
+
         (
           nameValidated,
           commandsValidated,
@@ -199,7 +218,8 @@ class ConfigYamlLoaderImpl extends ConfigYamlLoader {
           fieldNamesValidated,
           rawIncludeValidated,
           rawExcludeValidated,
-          excludeFieldsValidated
+          excludeFieldsValidated,
+          showEmptyFieldsValidated
         )
           .mapN(Feed.apply)
     }
@@ -223,7 +243,10 @@ class ConfigYamlLoaderImpl extends ConfigYamlLoader {
                 parseOptionalFeeds(fields, "feeds")
               val fieldNamesValidated =
                 parseOptionalFieldNames(fields, "fieldNames")
-              (fieldNamesValidated, feedsValidated).mapN(ConfigYaml.apply)
+              val showEmptyFieldsValidated =
+                parseOptionalBoolean(fields, "showEmptyFields")
+
+              (fieldNamesValidated, feedsValidated, showEmptyFieldsValidated).mapN(ConfigYaml.apply)
           }
       }
     }

json-log-viewer/shared/src/main/scala/ru/d10xa/jsonlogviewer/config/ResolvedConfig.scala

@@ -37,7 +37,8 @@ final case class ResolvedConfig(
   timestampBefore: Option[ZonedDateTime],
 
   // Other settings
-  grep: List[ConfigGrep]
+  grep: List[ConfigGrep],
+  showEmptyFields: Boolean
 )
 
 /** Resolves configuration by merging global and feed-specific settings into a
@@ -75,7 +76,9 @@ object ConfigResolver {
               // For each feed, merge its field names with global field names
               val feedFieldNames =
                 mergeFieldNames(globalFieldNames, feed.fieldNames)
-
+              val feedShowEmptyFields = feed.showEmptyFields
+                .orElse(yaml.showEmptyFields)
+                .getOrElse(config.showEmptyFields)
               ResolvedConfig(
                 feedName = feed.name,
                 commands = feed.commands,
@@ -89,7 +92,8 @@ object ConfigResolver {
                 excludeFields = feed.excludeFields,
                 timestampAfter = config.timestamp.after,
                 timestampBefore = config.timestamp.before,
-                grep = config.grep
+                grep = config.grep,
+                showEmptyFields = feedShowEmptyFields
               )
             }
           case _ =>
@@ -108,7 +112,8 @@ object ConfigResolver {
                 excludeFields = None,
                 timestampAfter = config.timestamp.after,
                 timestampBefore = config.timestamp.before,
-                grep = config.grep
+                grep = config.grep,
+                showEmptyFields = config.showEmptyFields
               )
             )
         }
@@ -128,7 +133,8 @@ object ConfigResolver {
             excludeFields = None,
             timestampAfter = config.timestamp.after,
             timestampBefore = config.timestamp.before,
-            grep = config.grep
+            grep = config.grep,
+            showEmptyFields = config.showEmptyFields
           )
         )
     }

json-log-viewer/shared/src/main/scala/ru/d10xa/jsonlogviewer/decline/Config.scala

@@ -12,7 +12,8 @@ final case class Config(
   grep: List[ConfigGrep],
   filter: Option[QueryAST],
   formatIn: Option[Config.FormatIn],
-  formatOut: Option[Config.FormatOut]
+  formatOut: Option[Config.FormatOut],
+  showEmptyFields: Boolean
 )
 
 object Config:

json-log-viewer/shared/src/main/scala/ru/d10xa/jsonlogviewer/decline/DeclineOpts.scala

@@ -114,6 +114,10 @@ object DeclineOpts {
     .map(ConfigFile.apply)
     .orNone
 
+  val showEmptyFields: Opts[Boolean] = Opts
+    .flag("show-empty-fields", help = "Show fields with empty values in output")
+    .orFalse
+
   val config: Opts[Config] =
     (
       configFile,
@@ -122,25 +126,28 @@ object DeclineOpts {
       grepConfig,
       filterConfig,
       formatIn,
-      formatOut
+      formatOut,
+      showEmptyFields
     ).mapN {
       case (
-            configFile,
-            fieldNamesConfig,
-            timestampConfig,
-            grepConfig,
-            filterConfig,
-            formatIn,
-            formatOut
-          ) =>
+        configFile,
+        fieldNamesConfig,
+        timestampConfig,
+        grepConfig,
+        filterConfig,
+        formatIn,
+        formatOut,
+        showEmptyFields
+        ) =>
         Config(
           configFile = configFile,
           fieldNames = fieldNamesConfig,
           timestamp = timestampConfig,
           grep = grepConfig,
           filter = filterConfig,
           formatIn = formatIn,
-          formatOut = formatOut
+          formatOut = formatOut,
+          showEmptyFields = showEmptyFields
         )
     }
 

json-log-viewer/shared/src/main/scala/ru/d10xa/jsonlogviewer/decline/yaml/ConfigYaml.scala

@@ -2,8 +2,9 @@ package ru.d10xa.jsonlogviewer.decline.yaml
 
 case class ConfigYaml(
   fieldNames: Option[FieldNames],
-  feeds: Option[List[Feed]]
+  feeds: Option[List[Feed]],
+  showEmptyFields: Option[Boolean]
 )
 
 object ConfigYaml:
-  val empty: ConfigYaml = ConfigYaml(None, None)
+  val empty: ConfigYaml = ConfigYaml(None, None, None)

json-log-viewer/shared/src/main/scala/ru/d10xa/jsonlogviewer/decline/yaml/Feed.scala

@@ -12,5 +12,6 @@ case class Feed(
   fieldNames: Option[FieldNames],
   rawInclude: Option[List[String]],
   rawExclude: Option[List[String]],
-  excludeFields: Option[List[String]]
+  excludeFields: Option[List[String]],
+  showEmptyFields: Option[Boolean]
 )

json-log-viewer/shared/src/main/scala/ru/d10xa/jsonlogviewer/formatout/ColorLineFormatter.scala

@@ -89,9 +89,13 @@ class ColorLineFormatter(
     otherAttributes: Map[String, String],
     needNewLine: Boolean
   ): Seq[Str] =
-    val filteredAttributes = otherAttributes.filterNot { case (key, _) =>
-      shouldExcludeField(key)
-    }
+    val filteredAttributes = otherAttributes
+      .filterNot { case (key, _) =>
+        shouldExcludeField(key)
+      }
+      .filterNot { case (_, value) =>
+        !config.showEmptyFields && isEmptyValue(value)
+      }
 
     filteredAttributes match
       case m if m.isEmpty => Nil
@@ -110,6 +114,9 @@ class ColorLineFormatter(
         )
         (if (needNewLine) strNewLine else strEmpty) :: s :: Nil
 
+  private def isEmptyValue(value: String): Boolean =
+    value.trim.isEmpty || value == "null" || value == "\"\"" || value == "{}" || value == "[]"
+
   def strPrefix(s: Option[String]): Seq[Str] =
     if (shouldExcludeField("prefix")) Nil
     else

json-log-viewer/shared/src/test/scala/ru/d10xa/jsonlogviewer/LogViewerStreamIntegrationTest.scala

@@ -40,13 +40,15 @@ class LogViewerStreamIntegrationTest extends CatsEffectSuite {
     grep = List.empty,
     filter = None,
     formatIn = Some(Config.FormatIn.Json),
-    formatOut = Some(Config.FormatOut.Raw)
+    formatOut = Some(Config.FormatOut.Raw),
+    showEmptyFields = false
   )
 
   test("config filters should update during live reload") {
     // Create config with INFO filter
     val infoFilter = QueryCompiler("level = 'INFO'").toOption
     val initialConfig = ConfigYaml(
+      showEmptyFields = None,
       fieldNames = None,
       feeds = Some(
         List(
@@ -59,7 +61,8 @@ class LogViewerStreamIntegrationTest extends CatsEffectSuite {
             fieldNames = None,
             rawInclude = None,
             rawExclude = None,
-            excludeFields = None
+            excludeFields = None,
+            showEmptyFields = None
           )
         )
       )
@@ -155,6 +158,7 @@ class LogViewerStreamIntegrationTest extends CatsEffectSuite {
   test("field mappings should update during live reload") {
     // Initial configuration with standard field names
     val initialConfig = ConfigYaml(
+      showEmptyFields = None,
       fieldNames = None,
       feeds = Some(
         List(
@@ -167,7 +171,8 @@ class LogViewerStreamIntegrationTest extends CatsEffectSuite {
             fieldNames = None,
             rawInclude = None,
             rawExclude = None,
-            excludeFields = None
+            excludeFields = None,
+            showEmptyFields = None
           )
         )
       )
@@ -180,6 +185,7 @@ class LogViewerStreamIntegrationTest extends CatsEffectSuite {
 
     // Updated config with custom field names mapping
     val updatedConfig = ConfigYaml(
+      showEmptyFields = None,
       fieldNames = Some(
         FieldNames(
           timestamp = Some("ts"),