Remove beta Salesforce Functions support (#83)

Support for Salesforce Functions is being retired:
https://devcenter.heroku.com/articles/salesforce-functions-retirement

Since Python support for Salesforce Functions is still in beta, support for
it is being removed now, prior to that of the GA Functions languages.

GUS-W-12613707.

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Removed
+
+- Removed support for Salesforce Functions. ([#83](https://github.com/heroku/buildpacks-python/pull/83))
 
 ## [0.5.0] - 2023-07-24
 

Cargo.toml

@@ -17,7 +17,6 @@ libcnb = "0.13"
 libherokubuildpack = { version = "0.13", default-features = false, features = ["log"] }
 serde = "1"
 tar = { version = "0.4", default-features = false }
-toml = "0.7"
 ureq = { version = "2", default-features = false, features = ["tls"] }
 
 [dev-dependencies]

src/errors.rs

@@ -1,10 +1,8 @@
 use crate::layers::pip_dependencies::PipDependenciesLayerError;
 use crate::layers::python::PythonLayerError;
 use crate::package_manager::DeterminePackageManagerError;
-use crate::project_descriptor::ProjectDescriptorError;
 use crate::python_version::{PythonVersion, PythonVersionError, DEFAULT_PYTHON_VERSION};
 use crate::runtime_txt::{ParseRuntimeTxtError, RuntimeTxtError};
-use crate::salesforce_functions::{CheckSalesforceFunctionError, FUNCTION_RUNTIME_PROGRAM_NAME};
 use crate::utils::{CommandError, DownloadUnpackArchiveError};
 use crate::BuildpackError;
 use indoc::{formatdoc, indoc};
@@ -42,38 +40,18 @@ pub(crate) fn on_error(error: libcnb::Error<BuildpackError>) {
 
 fn on_buildpack_error(error: BuildpackError) {
     match error {
-        BuildpackError::CheckSalesforceFunction(error) => on_check_salesforce_function_error(error),
         BuildpackError::DetectIo(io_error) => log_io_error(
             "Unable to complete buildpack detection",
             "determining if the Python buildpack should be run for this application",
             &io_error,
         ),
         BuildpackError::DeterminePackageManager(error) => on_determine_package_manager_error(error),
         BuildpackError::PipDependenciesLayer(error) => on_pip_dependencies_layer_error(error),
-        BuildpackError::ProjectDescriptor(error) => on_project_descriptor_error(error),
         BuildpackError::PythonLayer(error) => on_python_layer_error(error),
         BuildpackError::PythonVersion(error) => on_python_version_error(error),
     };
 }
 
-fn on_project_descriptor_error(error: ProjectDescriptorError) {
-    match error {
-        ProjectDescriptorError::Io(io_error) => log_io_error(
-            "Unable to read project.toml",
-            "reading the (optional) project.toml file",
-            &io_error,
-        ),
-        ProjectDescriptorError::Parse(toml_error) => log_error(
-            "Invalid project.toml",
-            formatdoc! {"
-                A parsing/validation error error occurred whilst loading the project.toml file.
-                
-                Details: {toml_error}
-            "},
-        ),
-    };
-}
-
 fn on_determine_package_manager_error(error: DeterminePackageManagerError) {
     match error {
         DeterminePackageManagerError::Io(io_error) => log_io_error(
@@ -239,42 +217,6 @@ fn on_pip_dependencies_layer_error(error: PipDependenciesLayerError) {
     };
 }
 
-fn on_check_salesforce_function_error(error: CheckSalesforceFunctionError) {
-    match error {
-        CheckSalesforceFunctionError::Io(io_error) => log_io_error(
-            "Unable to run the Salesforce Functions self-check command",
-            &format!("running the '{FUNCTION_RUNTIME_PROGRAM_NAME} check' command"),
-            &io_error,
-        ),
-        CheckSalesforceFunctionError::NonZeroExitStatus(output) => log_error(
-            "The Salesforce Functions self-check failed",
-            formatdoc! {"
-                The '{FUNCTION_RUNTIME_PROGRAM_NAME} check' command failed ({exit_status}), indicating
-                there is a problem with the Python Salesforce Function in this project.
-                
-                Details:
-                {stderr}
-                ",
-                exit_status = output.status,
-                stderr = String::from_utf8_lossy(&output.stderr),
-            },
-        ),
-        CheckSalesforceFunctionError::ProgramNotFound => log_error(
-            "The Salesforce Functions package is not installed",
-            formatdoc! {"
-                The '{FUNCTION_RUNTIME_PROGRAM_NAME}' program that is required for Python Salesforce
-                Functions could not be found.
-
-                Check that the 'salesforce-functions' Python package is listed as a
-                dependency in 'requirements.txt'.
-                
-                If this project is not intended to be a Salesforce Function, remove the
-                'type = \"function\"' declaration from 'project.toml' to skip this check.
-            "},
-        ),
-    };
-}
-
 fn log_io_error(header: &str, occurred_whilst: &str, io_error: &io::Error) {
     // We don't suggest opening a support ticket, since a subset of I/O errors can be caused
     // by issues in the application. In the future, perhaps we should try and split these out?

src/main.rs

@@ -9,20 +9,16 @@ mod errors;
 mod layers;
 mod package_manager;
 mod packaging_tool_versions;
-mod project_descriptor;
 mod python_version;
 mod runtime_txt;
-mod salesforce_functions;
 mod utils;
 
 use crate::layers::pip_cache::PipCacheLayer;
 use crate::layers::pip_dependencies::{PipDependenciesLayer, PipDependenciesLayerError};
 use crate::layers::python::{PythonLayer, PythonLayerError};
 use crate::package_manager::{DeterminePackageManagerError, PackageManager};
 use crate::packaging_tool_versions::PackagingToolVersions;
-use crate::project_descriptor::ProjectDescriptorError;
 use crate::python_version::PythonVersionError;
-use crate::salesforce_functions::CheckSalesforceFunctionError;
 use libcnb::build::{BuildContext, BuildResult, BuildResultBuilder};
 use libcnb::data::layer_name;
 use libcnb::detect::{DetectContext, DetectResult, DetectResultBuilder};
@@ -55,8 +51,6 @@ impl Buildpack for PythonBuildpack {
     fn build(&self, context: BuildContext<Self>) -> libcnb::Result<BuildResult, Self::Error> {
         // We perform all project analysis up front, so the build can fail early if the config is invalid.
         // TODO: Add a "Build config" header and list all config in one place?
-        let is_function = salesforce_functions::is_function_project(&context.app_dir)
-            .map_err(BuildpackError::ProjectDescriptor)?;
         let package_manager = package_manager::determine_package_manager(&context.app_dir)
             .map_err(BuildpackError::DeterminePackageManager)?;
 
@@ -86,7 +80,7 @@ impl Buildpack for PythonBuildpack {
 
         // Create the layers for the application dependencies and package manager cache.
         // In the future support will be added for package managers other than pip.
-        let dependencies_layer_env = match package_manager {
+        match package_manager {
             PackageManager::Pip => {
                 log_header("Installing dependencies using Pip");
                 let pip_cache_layer = context.handle_layer(
@@ -106,20 +100,8 @@ impl Buildpack for PythonBuildpack {
                 pip_layer.env
             }
         };
-        command_env = dependencies_layer_env.apply(Scope::Build, &command_env);
 
-        if is_function {
-            log_header("Validating Salesforce Function");
-            salesforce_functions::check_function(&command_env)
-                .map_err(BuildpackError::CheckSalesforceFunction)?;
-            log_info("Function passed validation.");
-
-            BuildResultBuilder::new()
-                .launch(salesforce_functions::launch_config())
-                .build()
-        } else {
-            BuildResultBuilder::new().build()
-        }
+        BuildResultBuilder::new().build()
     }
 
     fn on_error(&self, error: libcnb::Error<Self::Error>) {
@@ -129,16 +111,12 @@ impl Buildpack for PythonBuildpack {
 
 #[derive(Debug)]
 pub(crate) enum BuildpackError {
-    /// Errors running the `sf-functions-python check` command.
-    CheckSalesforceFunction(CheckSalesforceFunctionError),
     /// IO errors when performing buildpack detection.
     DetectIo(io::Error),
     /// Errors determining which Python package manager to use for a project.
     DeterminePackageManager(DeterminePackageManagerError),
     /// Errors installing the project's dependencies into a layer using Pip.
     PipDependenciesLayer(PipDependenciesLayerError),
-    /// Errors reading and parsing a `project.toml` file.
-    ProjectDescriptor(ProjectDescriptorError),
     /// Errors installing Python and required packaging tools into a layer.
     PythonLayer(PythonLayerError),
     /// Errors determining which Python version to use for a project.