From ea09e897c66c4555e5a3ce8aff3122063203294e Mon Sep 17 00:00:00 2001 From: Sanskar Bhushan Date: Mon, 7 Aug 2023 14:22:00 +0530 Subject: [PATCH] adding printing diff functionality in flux diff artifact Signed-off-by: Sanskar Bhushan --- cmd/flux/diff_artifact.go | 118 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 114 insertions(+), 4 deletions(-) diff --git a/cmd/flux/diff_artifact.go b/cmd/flux/diff_artifact.go index edfd93827b..d785730990 100644 --- a/cmd/flux/diff_artifact.go +++ b/cmd/flux/diff_artifact.go @@ -1,5 +1,5 @@ /* -Copyright 2022 The Flux authors +Copyright 2023 The Flux authors Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. @@ -17,12 +17,18 @@ limitations under the License. package main import ( + "archive/tar" + "bytes" "context" "fmt" + "io" "os" oci "github.com/fluxcd/pkg/oci/client" sourcev1 "github.com/fluxcd/source-controller/api/v1beta2" + "github.com/google/go-containerregistry/pkg/crane" + + "github.com/sergi/go-diff/diffmatchpatch" "github.com/spf13/cobra" "github.com/fluxcd/flux2/v2/internal/flags" @@ -42,6 +48,7 @@ type diffArtifactFlags struct { creds string provider flags.SourceOCIProvider ignorePaths []string + compareTo string // New field to capture the URL or local path for comparison } var diffArtifactArgs = newDiffArtifactArgs() @@ -57,6 +64,7 @@ func init() { diffArtifactCmd.Flags().StringVar(&diffArtifactArgs.creds, "creds", "", "credentials for OCI registry in the format [:] if --provider is generic") diffArtifactCmd.Flags().Var(&diffArtifactArgs.provider, "provider", sourceOCIRepositoryArgs.provider.Description()) diffArtifactCmd.Flags().StringSliceVar(&diffArtifactArgs.ignorePaths, "ignore-paths", excludeOCI, "set paths to ignore in .gitignore format") + diffArtifactCmd.Flags().BoolP("verbose", "v", false, "Show verbose output") // Add a --verbose flag specific to diff artifact. diffCmd.AddCommand(diffArtifactCmd) } @@ -67,7 +75,7 @@ func diffArtifactCmdRun(cmd *cobra.Command, args []string) error { ociURL := args[0] if diffArtifactArgs.path == "" { - return fmt.Errorf("invalid path %q", diffArtifactArgs.path) + return fmt.Errorf("path is required") } url, err := oci.ParseArtifactURL(ociURL) @@ -103,10 +111,112 @@ func diffArtifactCmdRun(cmd *cobra.Command, args []string) error { } } - if err := ociClient.Diff(ctx, url, diffArtifactArgs.path, diffArtifactArgs.ignorePaths); err != nil { + ociContents, err := fetchContentsFromURL(ctx, url) + if err != nil { return err } - logger.Successf("no changes detected") + compareToContents, err := fetchContentsFromLocalPath(diffArtifactArgs.path) + if err != nil { + return err + } + + diffOutput, err := diffContents(ociContents, compareToContents) + if err != nil { + return err + } + + fmt.Printf("Diff between OCI artifact (%s) and local path (%s):\n", ociURL, diffArtifactArgs.path) + + // Show verbose output if the --verbose flag is set + if verbose, _ := cmd.Flags().GetBool("verbose"); verbose { + fmt.Println("Printing diff...") + } + + fmt.Println(diffOutput) + return nil } + +func fetchContentsFromURL(ctx context.Context, url string) ([]byte, error) { + img, err := crane.Pull(url) + if err != nil { + return nil, fmt.Errorf("failed to pull OCI artifact: %w", err) + } + + layers, err := img.Layers() + if err != nil { + return nil, fmt.Errorf("failed to list layers: %w", err) + } + + if len(layers) < 1 { + return nil, fmt.Errorf("no layers found in OCI artifact") + } + + // Create a buffer to store the contents of the artifact + var contentsBuffer bytes.Buffer + + // Extract the content of the first layer + layerContent, err := layers[0].Compressed() + if err != nil { + return nil, fmt.Errorf("failed to extract layer content: %w", err) + } + defer layerContent.Close() + + // Use tar.NewReader to read the contents from the OCI artifact + tarReader := tar.NewReader(layerContent) + for { + _, err := tarReader.Next() + if err == io.EOF { + break + } + if err != nil { + return nil, fmt.Errorf("failed to read tar header: %w", err) + } + + // Read the file contents and write them to the buffer + if _, err := io.Copy(&contentsBuffer, tarReader); err != nil { + return nil, fmt.Errorf("failed to read tar entry contents: %w", err) + } + } + + return contentsBuffer.Bytes(), nil +} + +func fetchContentsFromLocalPath(path string) ([]byte, error) { + // Open the local file or directory at the given path + file, err := os.Open(path) + if err != nil { + return nil, fmt.Errorf("failed to open local file/directory: %w", err) + } + defer file.Close() + + // Create a buffer to store the contents + var contentsBuffer bytes.Buffer + + // Use tar.NewReader to read the contents from the file/directory + tarReader := tar.NewReader(file) + for { + _, err := tarReader.Next() + if err == io.EOF { + break + } + if err != nil { + return nil, fmt.Errorf("failed to read tar header: %w", err) + } + + // Read the file contents and write them to the buffer + if _, err := io.Copy(&contentsBuffer, tarReader); err != nil { + return nil, fmt.Errorf("failed to read tar entry contents: %w", err) + } + } + + return contentsBuffer.Bytes(), nil +} + +func diffContents(contents1, contents2 []byte) (string, error) { + dmp := diffmatchpatch.New() + + diffs := dmp.DiffMain(string(contents1), string(contents2), false) + return dmp.DiffPrettyText(diffs), nil +}