Improve error handling

Closes #13

Author: subdan

Example/Gemfile.lock

@@ -14,20 +14,20 @@ GEM
       json (>= 1.5.1)
     atomos (0.1.3)
     aws-eventstream (1.1.0)
-    aws-partitions (1.346.0)
-    aws-sdk-core (3.104.3)
+    aws-partitions (1.359.0)
+    aws-sdk-core (3.105.0)
       aws-eventstream (~> 1, >= 1.0.2)
       aws-partitions (~> 1, >= 1.239.0)
       aws-sigv4 (~> 1.1)
       jmespath (~> 1.0)
-    aws-sdk-kms (1.36.0)
+    aws-sdk-kms (1.37.0)
       aws-sdk-core (~> 3, >= 3.99.0)
       aws-sigv4 (~> 1.1)
-    aws-sdk-s3 (1.75.0)
-      aws-sdk-core (~> 3, >= 3.104.1)
+    aws-sdk-s3 (1.79.0)
+      aws-sdk-core (~> 3, >= 3.104.3)
       aws-sdk-kms (~> 1)
       aws-sigv4 (~> 1.1)
-    aws-sigv4 (1.2.1)
+    aws-sigv4 (1.2.2)
       aws-eventstream (~> 1, >= 1.0.2)
     babosa (1.0.3)
     claide (1.0.3)
@@ -93,7 +93,7 @@ GEM
     faraday_middleware (1.0.0)
       faraday (~> 1.0)
     fastimage (2.2.0)
-    fastlane (2.153.1)
+    fastlane (2.156.1)
       CFPropertyList (>= 2.3, < 4.0.0)
       addressable (>= 2.3, < 3.0.0)
       aws-sdk-s3 (~> 1.0)
@@ -147,14 +147,14 @@ GEM
     google-cloud-env (1.3.3)
       faraday (>= 0.17.3, < 2.0)
     google-cloud-errors (1.0.1)
-    google-cloud-storage (1.26.2)
+    google-cloud-storage (1.27.0)
       addressable (~> 2.5)
       digest-crc (~> 0.4)
       google-api-client (~> 0.33)
       google-cloud-core (~> 1.2)
       googleauth (~> 0.9)
       mini_mime (~> 1.0)
-    googleauth (0.13.0)
+    googleauth (0.13.1)
       faraday (>= 0.17.3, < 2.0)
       jwt (>= 1.4, < 3.0)
       memoist (~> 0.16)
@@ -169,7 +169,7 @@ GEM
       concurrent-ruby (~> 1.0)
     jmespath (1.4.0)
     json (2.3.1)
-    jwt (2.2.1)
+    jwt (2.2.2)
     memoist (0.16.2)
     mini_magick (4.10.1)
     mini_mime (1.0.2)
@@ -181,7 +181,7 @@ GEM
     nap (1.1.0)
     naturally (2.2.0)
     netrc (0.11.0)
-    os (1.1.0)
+    os (1.1.1)
     plist (3.5.0)
     public_suffix (4.0.5)
     rake (13.0.1)
@@ -221,7 +221,7 @@ GEM
     unf_ext (0.0.7.7)
     unicode-display_width (1.7.0)
     word_wrap (1.0.0)
-    xcodeproj (1.17.1)
+    xcodeproj (1.18.0)
       CFPropertyList (>= 2.3.3, < 4.0)
       atomos (~> 0.1.3)
       claide (>= 1.0.2, < 2.0)

Sources/FigmaAPI/Model/FigmaClientError.swift

@@ -4,5 +4,20 @@ struct FigmaClientError: Decodable, LocalizedError {
     let status: Int
     let err: String
 
-    var errorDescription: String? { "Figma API: \(err)" }
+    var errorDescription: String? {
+        switch err {
+        case "Not found":
+            return "Figma file not found. Check lightFileId and darkFileId (if you project supports dark mode) in the yaml config file."
+        default:
+            return "Figma API: \(err)"
+        }
+    }
+}
+
+extension FigmaClientError: Equatable {
+    
+    static let notFound = FigmaClientError(
+        status: 404,
+        err: "Not found"
+    )
 }

Sources/FigmaExport/Loaders/ColorsLoader.swift

@@ -22,6 +22,11 @@ final class ColorsLoader {
 
     private func loadColors(fileId: String) throws -> [Color] {
         let styles = try loadStyles(fileId: fileId)
+        
+        guard !styles.isEmpty else {
+            throw FigmaExportError.stylesNotFound
+        }
+        
         let nodes = try loadNodes(fileId: fileId, nodeIds: styles.map { $0.nodeId } )
         return nodesAndStylesToColors(nodes: nodes, styles: styles)
     }

Sources/FigmaExport/Loaders/ImagesLoader.swift

@@ -91,6 +91,11 @@ final class ImagesLoader {
 
     private func _loadImages(fileId: String, frameName: FrameName, params: FormatParams, filter: String? = nil) throws -> [Image] {
         let imagesDict = try fetchImageComponents(fileId: fileId, frameName: frameName, filter: filter)
+        
+        guard !imagesDict.isEmpty else {
+            throw FigmaExportError.componentsNotFound
+        }
+        
         let imagesIds: [NodeId] = imagesDict.keys.map { $0 }
         let imageIdToImagePath = try loadImages(fileId: fileId, nodeIds: imagesIds, params: params)
 
@@ -106,6 +111,11 @@ final class ImagesLoader {
 
     private func _loadPNGImages(fileId: String, frameName: FrameName, filter: String? = nil) throws -> [ImagePack] {
         let imagesDict = try fetchImageComponents(fileId: fileId, frameName: frameName, filter: filter)
+        
+        guard !imagesDict.isEmpty else {
+            throw FigmaExportError.componentsNotFound
+        }
+        
         let imagesIds: [NodeId] = imagesDict.keys.map { $0 }
 
         let imageIdToImagePath1 = try loadImages(fileId: fileId, nodeIds: imagesIds, params: PNGParams(scale: 1))

Sources/FigmaExport/Processor/AssetsValidatorError.swift

@@ -11,17 +11,17 @@ enum AssetsValidatorError: LocalizedError {
     var errorDescription: String? {
         switch self {
         case .badName(let name):
-            return "Неправильное название «\(name)»"
+            return "Bad asset name «\(name)»"
         case .countMismatch(let light, let dark):
-            return "Количество ассетов не совпадает. В светлой теме их \(light), а в темной теме \(dark)."
+            return "The number of assets doesn’t match. Light theme contains \(light), and dark \(dark)."
         case .lightAssetsNotFoundInDarkPalette(let lights):
-            return "В темной теме не найдены ассеты: \(lights.joined(separator: ", ")), которые есть в светлой теме."
+            return "Dark theme doesn’t contains following assets: \(lights.joined(separator: ", ")), which exists in light theme. Add these assets to dark theme and publish to the Team Library."
         case .darkAssetsNotFoundInLightPalette(let darks):
-            return "В светлой теме не найдены ассеты: \(darks.joined(separator: ", ")), которые есть в темной теме."
+            return "Light theme doesn’t contains following assets: \(darks.joined(separator: ", ")), which exists in dark theme. Add these assets to light theme and publish to the Team Library."
         case .foundDuplicate(let assetName):
-            return "Ассет \(assetName) встречается несколько раз."
+            return "Found duplicates of asset with name \(assetName). Remove duplicates."
         case .descriptionMismatch(let assetName, let light, let dark):
-            return "Ассет \(assetName) имеет разный description. В тёмной теме «\(dark)», а в светлой «\(light)»"
+            return "Asset with name \(assetName) have different description. In dark theme «\(dark)», in light theme «\(light)»"
         }
     }
 }

Sources/FigmaExport/main.swift

@@ -3,11 +3,17 @@ import Foundation
 
 enum FigmaExportError: LocalizedError {
 
+    case stylesNotFound
+    case componentsNotFound
     case accessTokenNotFound
     case colorsAssetsFolderNotSpecified
 
     var errorDescription: String? {
         switch self {
+        case .stylesNotFound:
+            return "Color styles not found in the Figma file. Have you published Styles to the Library?"
+        case .componentsNotFound:
+            return "Components not found in the Figma file. Have you published Components to the Library?"
         case .accessTokenNotFound:
             return "Environment varibale FIGMA_PERSONAL_TOKEN not specified."
         case .colorsAssetsFolderNotSpecified: