Add support for __init__.py as default scriptFile for Python (#7697)

Author: pgombar

src/WebJobs.Script/Host/HostFunctionMetadataProvider.cs

@@ -240,11 +240,13 @@ internal static string DeterminePrimaryScriptFile(string scriptFile, string scri
                 {
                     // if there is a "run" file, that file is primary,
                     // for Node, any index.js file is primary
+                    // for Python, __init__.py file is primary
                     // TODO #6955: Get default function file name from language worker configs
                     functionPrimary = functionFiles.FirstOrDefault(p =>
                         fileSystem.Path.GetFileNameWithoutExtension(p).ToLowerInvariant() == "run" ||
                         fileSystem.Path.GetFileName(p).ToLowerInvariant() == "index.js" ||
-                        fileSystem.Path.GetFileName(p).ToLowerInvariant() == "index.mjs");
+                        fileSystem.Path.GetFileName(p).ToLowerInvariant() == "index.mjs" ||
+                        fileSystem.Path.GetFileName(p).ToLowerInvariant() == "__init__.py");
                 }
             }
 

test/WebJobs.Script.Tests/FunctionMetadataProviderTests.cs

@@ -217,6 +217,22 @@ public void DeterminePrimaryScriptFile_MultipleFiles_RunFilePresent()
             Assert.Equal(@"c:\functions\Run.csx", scriptFile);
         }
 
+        [Fact]
+        public void DeterminePrimaryScriptFile_MultipleFiles_InitFilePresent()
+        {
+            var functionConfig = new JObject();
+            var files = new Dictionary<string, MockFileData>
+            {
+                { @"c:\functions\__init__.py", new MockFileData(string.Empty) },
+                { @"c:\functions\helloworld.py", new MockFileData(string.Empty) },
+                { @"c:\functions\test.txt", new MockFileData(string.Empty) }
+            };
+            var fileSystem = new MockFileSystem(files);
+
+            string scriptFile = HostFunctionMetadataProvider.DeterminePrimaryScriptFile(null, @"c:\functions", fileSystem);
+            Assert.Equal(@"c:\functions\__init__.py", scriptFile);
+        }
+
         [Fact]
         public void DeterminePrimaryScriptFile_SingleFile()
         {
@@ -245,35 +261,37 @@ public void DeterminePrimaryScriptFile_MultipleFiles_RunTrumpsIndex()
             Assert.Equal(@"c:\functions\run.js", scriptFile);
         }
 
-        [Fact]
-        public void DeterminePrimaryScriptFile_MultipleFiles_IndexFilePresent()
+        [Theory]
+        [InlineData("index.js", @"c:\functions\index.js")]
+        [InlineData("__init__.py", @"c:\functions\__init__.py")]
+        public void DeterminePrimaryScriptFile_MultipleFiles_DefaultFilePresent(string scriptFileProperty, string expectedScriptFilePath)
         {
             var files = new Dictionary<string, MockFileData>
             {
-                { @"c:\functions\index.js", new MockFileData(string.Empty) },
+                { expectedScriptFilePath, new MockFileData(string.Empty) },
                 { @"c:\functions\test.txt", new MockFileData(string.Empty) }
             };
             var fileSystem = new MockFileSystem(files);
 
-            string scriptFile = HostFunctionMetadataProvider.DeterminePrimaryScriptFile("index.js", @"c:\functions", fileSystem);
-            Assert.Equal(@"c:\functions\index.js", scriptFile);
+            string scriptFile = HostFunctionMetadataProvider.DeterminePrimaryScriptFile(scriptFileProperty, @"c:\functions", fileSystem);
+            Assert.Equal(expectedScriptFilePath, scriptFile);
         }
 
         [Theory]
         [InlineData("run.py", @"c:\functions\run.py")]
         [InlineData("queueTrigger.py", @"c:\functions\queueTrigger.py")]
         [InlineData("helper.py", @"c:\functions\helper.py")]
         [InlineData("test.txt", @"c:\functions\test.txt")]
-        public void DeterminePrimaryScriptFile_MultipleFiles_ConfigTrumpsConvention(string scriptFileProperty, string expedtedScriptFilePath)
+        public void DeterminePrimaryScriptFile_MultipleFiles_ConfigTrumpsConvention(string scriptFileProperty, string expectedScriptFilePath)
         {
             var files = new Dictionary<string, MockFileData>
             {
-                { expedtedScriptFilePath, new MockFileData(string.Empty) }
+                { expectedScriptFilePath, new MockFileData(string.Empty) }
             };
             var fileSystem = new MockFileSystem(files);
 
             string actualScriptFilePath = HostFunctionMetadataProvider.DeterminePrimaryScriptFile(scriptFileProperty, @"c:\functions", fileSystem);
-            Assert.Equal(expedtedScriptFilePath, actualScriptFilePath);
+            Assert.Equal(expectedScriptFilePath, actualScriptFilePath);
         }
 
         [Theory]
@@ -285,6 +303,7 @@ public void DeterminePrimaryScriptFile_MultipleFiles_SourceFileSpecified(string
             {
                 { @"c:\functions\queueTrigger.py", new MockFileData(string.Empty) },
                 { @"c:\functions\helper.py", new MockFileData(string.Empty) },
+                { @"c:\functions\__init__.py", new MockFileData(string.Empty) },
                 { @"c:\functions\test.txt", new MockFileData(string.Empty) }
             };
             var fileSystem = new MockFileSystem(files);