Enable Python 3.8 in V3 worker (#603)

* Enable Python 3.8 in V3 worker

* Also allow python version 3.8 in worker.py

pack/Microsoft.Azure.Functions.V2.PythonWorker.nuspec

@@ -18,7 +18,7 @@
     <file src="..\3.7_WINDOWS_X86\**" target="tools\3.7\WINDOWS\X86" />
     <file src="..\3.7_LINUX_X64\**" target="tools\3.7\LINUX\X64" />
     <file src="..\3.7_OSX_X64\**" target="tools\3.7\OSX\X64" />
-    <file src="..\python\prod\worker.config.json" target="tools" />
-    <file src="Microsoft.Azure.Functions.V2.PythonWorker.targets" target="build" />
+    <file src="..\python\prodV2\worker.config.json" target="tools" />
+    <file src="Microsoft.Azure.Functions.PythonWorker.targets" target="build" />
   </files>
 </package>

pack/Microsoft.Azure.Functions.V3.PythonWorker.nuspec

@@ -22,7 +22,7 @@
     <file src="..\3.8_WINDOWS_X86\**" target="tools\3.8\WINDOWS\X86" />
     <file src="..\3.8_LINUX_X64\**" target="tools\3.8\LINUX\X64" />
     <file src="..\3.8_OSX_X64\**" target="tools\3.8\OSX\X64" />
-    <file src="..\python\prod\worker.config.json" target="tools" />
-    <file src="Microsoft.Azure.Functions.V3.PythonWorker.targets" target="build" />
+    <file src="..\python\prodV3\worker.config.json" target="tools" />
+    <file src="Microsoft.Azure.Functions.PythonWorker.targets" target="build" />
   </files>
 </package>

pack/Microsoft.Azure.Functions.V3.PythonWorker.targets

@@ -1,25 +0,0 @@
-<Project>
-  <Target Name="Initialize" AfterTargets="Publish;Build">
-    <CreateItem Include="$(MSBuildThisFileDirectory)\..\">
-      <Output ItemName="MSBuildThisFileDirectoryParentDirectory" TaskParameter="Include"/>
-    </CreateItem>
-
-    <CreateProperty Value="%(MSBuildThisFileDirectoryParentDirectory.Fullpath)">
-        <Output PropertyName="NugetRoot" TaskParameter="Value"/>
-    </CreateProperty>
-
-    <ItemGroup>
-        <SourceFiles Include="$(NugetRoot)tools\**\*.*"/>
-    </ItemGroup>
-  </Target>
-
-  <Target Name="CopyOnPublish" DependsOnTargets="Initialize" AfterTargets="Publish">
-        <Copy SourceFiles="@(SourceFiles)"
-            DestinationFiles="@(SourceFiles->'$(PublishDir)\workers\python\%(RecursiveDir)%(Filename)%(Extension)')" />
-  </Target>
-
-  <Target Name="CopyOnBuild" DependsOnTargets="Initialize" AfterTargets="Build">
-        <Copy SourceFiles="@(SourceFiles)"
-            DestinationFiles="@(SourceFiles->'$(OutDir)\workers\python\%(RecursiveDir)%(Filename)%(Extension)')" />
-  </Target>
-</Project>

python/prodV3/worker.config.json

@@ -0,0 +1,12 @@
+{
+    "description":{
+        "language":"python",
+        "defaultRuntimeVersion":"3.6",
+        "supportedOperatingSystems":["LINUX", "OSX", "WINDOWS"],
+        "supportedRuntimeVersions":["3.6", "3.7", "3.8"],
+        "supportedArchitectures":["X64", "X86"],
+        "extensions":[".py"],
+        "defaultExecutablePath":"python",
+        "defaultWorkerPath":"%FUNCTIONS_WORKER_RUNTIME_VERSION%/{os}/{architecture}/worker.py"
+    }
+}

python/prodV3/worker.py

@@ -0,0 +1,61 @@
+import os
+import sys
+
+from pathlib import Path
+
+# User packages
+PKGS_PATH = "site/wwwroot/.python_packages"
+VENV_PKGS_PATH = "site/wwwroot/worker_venv"
+
+PKGS_36 = "lib/python3.6/site-packages"
+PKGS = "lib/site-packages"
+
+# Azure environment variables
+AZURE_WEBSITE_INSTANCE_ID = "WEBSITE_INSTANCE_ID"
+AZURE_CONTAINER_NAME = "CONTAINER_NAME"
+
+
+def is_azure_environment():
+    return (AZURE_CONTAINER_NAME in os.environ
+            or AZURE_WEBSITE_INSTANCE_ID in os.environ)
+
+
+def determine_user_pkg_paths():
+    minor_version = sys.version_info[1]
+
+    home = Path.home()
+    pkgs_path = os.path.join(home, PKGS_PATH)
+    venv_pkgs_path = os.path.join(home, VENV_PKGS_PATH)
+
+    user_pkg_paths = []
+    if minor_version == 6:
+        user_pkg_paths.append(os.path.join(venv_pkgs_path, PKGS_36))
+        user_pkg_paths.append(os.path.join(pkgs_path, PKGS_36))
+        user_pkg_paths.append(os.path.join(pkgs_path, PKGS))
+    elif minor_version in (7, 8):
+        user_pkg_paths.append(os.path.join(pkgs_path, PKGS))
+    else:
+        raise RuntimeError(f'Unsupported Python version: 3.{minor_version}')
+
+    return user_pkg_paths
+
+
+if __name__ == '__main__':
+    # worker.py lives in the same directory as azure_functions_worker
+    func_worker_dir = str(Path(__file__).absolute().parent)
+    env = os.environ
+
+    if is_azure_environment():
+        user_pkg_paths = determine_user_pkg_paths()
+
+        joined_pkg_paths = os.pathsep.join(user_pkg_paths)
+        env['PYTHONPATH'] = f'{joined_pkg_paths}:{func_worker_dir}'
+        os.execve(sys.executable,
+                  [sys.executable, '-m', 'azure_functions_worker']
+                  + sys.argv[1:],
+                  env)
+    else:
+        sys.path.insert(1, func_worker_dir)
+        from azure_functions_worker import main
+
+        main.main()