Merge pull request #7 from skip77/main

README.md

@@ -1,22 +1,23 @@
 # srpmproc
 Upstream package importer with auto patching. Reference implementation for OpenPatch
 
-# Usage
+## Usage
 ```
 Usage:
   srpmproc [flags]
   srpmproc [command]
 
 Available Commands:
-  fetch
+  fetch       
   help        Help about any command
 
 Flags:
       --basic-password string           Basic auth password
       --basic-username string           Basic auth username
       --branch-prefix string            Branch prefix (replaces import-branch-prefix) (default "r")
       --branch-suffix string            Branch suffix to use for imported branches
-      --cdn-url string                  CDN URL to download blobs from (default "https://git.centos.org/sources")
+      --cdn string                      CDN URL shortcuts for well-known distros, auto-assigns --cdn-url.  Valid values:  rocky8, rocky, fedora, centos, centos-stream.  Setting this overrides --cdn-url
+      --cdn-url string                  CDN URL to download blobs from. Simple URL follows default rocky/centos patterns. Can be customized using macros (see docs) (default "https://git.centos.org/sources")
       --git-committer-email string      Email of committer (default "[email protected]")
       --git-committer-name string       Name of committer (default "rockyautomation")
   -h, --help                            help for srpmproc
@@ -28,16 +29,51 @@ Flags:
       --no-dup-mode                     If enabled, skips already imported tags
       --no-storage-download             If enabled, blobs are always downloaded from upstream
       --no-storage-upload               If enabled, blobs are not uploaded to blob storage
+      --package-release string          Package release to fetch
+      --package-version string          Package version to fetch
       --rpm-prefix string               Where to retrieve SRPM content. Only used when source-rpm is not a local file (default "https://git.centos.org/rpms")
       --single-tag string               If set, only this tag is imported
       --source-rpm string               Location of RPM to process
       --ssh-key-location string         Location of the SSH key to use to authenticate against upstream
       --ssh-user string                 SSH User (default "git")
       --storage-addr string             Bucket to use as blob storage
       --strict-branch-mode              If enabled, only branches with the calculated name are imported and not prefix only
+      --taglessmode                     Tagless mode:  If set, pull the latest commit from the branch and determine version numbers from spec file.  This is auto-tried if tags aren't found.
       --tmpfs-mode string               If set, packages are imported to path and patched but not pushed
       --upstream-prefix string          Upstream git repository prefix
       --version int                     Upstream version
 
 Use "srpmproc [command] --help" for more information about a command.
 ```
+
+<br />
+
+## Examples:
+
+1. Import the kernel package from git.centos.org/rpms/, to local folder /opt/gitroot/rpms/kernel.git/ .  Download the lookaside source tarballs from the default CentOS file server location to local folder `/opt/fake_s3/` .  We want to grab branch "c8" (import prefix plus RHEL version), and it will be committed as branch "r8" (branch prefix plus RHEL version).  This assumes that `/opt/fake_s3` exists, and `/opt/gitroot/rpms/kernel.git` exists and is a git repository of some kind (even an empty one).
+
+```
+srpmproc --branch-prefix "r"  --import-branch-prefix "c"  --rpm-prefix "https://git.centos.org/rpms" --version 8 --storage-addr file:///opt/fake_s3  --upstream-prefix file:///opt/gitroot   --cdn centos --strict-branch-mode --source-rpm kernel
+```
+
+<br />
+
+## CDN and --cdn-url
+The --cdn-url option allows for Go-style templates to craft complex URL patterns.  These templates are: `{{.Name}}` (package name), `{{.Hash}}` (hash of lookaside file), `{{.Hashtype}}` (hash type of file, like "sha256" or "sha512"), `{{.Branch}}` (the branch we are importing), and `{{.Filename}}` (the lookaside file's name as it appears in SOURCES/).  You can add these values as part of --cdn-url to craft your lookaside pattern.
+
+
+For example, if I wanted my lookaside downloads to come from CentOS 9 Stream, I would use as part of my command:
+```
+--cdn-url "https://sources.stream.centos.org/sources/rpms/{{.Name}}/{{.Filename}}/{{.Hashtype}}/{{.Hash}}/{{.Filename}}"
+```
+
+
+**Default Behavior:**  If these templates are not used, the default behavior of `--cdn-url` is to fall back on the traditional RHEL import pattern:  `<CDN_URL>/<NAME>/<BRANCH>/<HASH>` .  If that fails, a further fallback is attempted, the simple: `<CDN_URL>/<HASH>`.  These cover the common Rocky Linux and RHEL/CentOS imports if the base lookaside URL is the only thing given.  If no `--cdn-url` is specified, it defaults to "https://git.centos.org/sources" (for RHEL imports into Rocky Linux)
+
+
+**CDN Shorthand:** For convenience, some lookaside patterns for popular distros are provided via the `--cdn` option.  You can specify this without needing to use the longer `--cdn-url`.  For example, when importing from CentOS 9 Stream, you could use `--cdn centos-stream`
+
+
+
+
+

cmd/srpmproc/main.go

@@ -58,7 +58,7 @@ var (
 	packageVersion       string
 	packageRelease       string
 	taglessMode          bool
-	altLookAside         bool
+	cdn                  string
 )
 
 var root = &cobra.Command{
@@ -96,7 +96,7 @@ func mn(_ *cobra.Command, _ []string) {
 		PackageVersion:       packageVersion,
 		PackageRelease:       packageRelease,
 		TaglessMode:          taglessMode,
-		AltLookAside:         altLookAside,
+		Cdn:                  cdn,
 	})
 	if err != nil {
 		log.Fatal(err)
@@ -131,7 +131,7 @@ func main() {
 	root.Flags().StringVar(&rpmPrefix, "rpm-prefix", "https://git.centos.org/rpms", "Where to retrieve SRPM content. Only used when source-rpm is not a local file")
 	root.Flags().StringVar(&importBranchPrefix, "import-branch-prefix", "c", "Import branch prefix")
 	root.Flags().StringVar(&branchPrefix, "branch-prefix", "r", "Branch prefix (replaces import-branch-prefix)")
-	root.Flags().StringVar(&cdnUrl, "cdn-url", "https://git.centos.org/sources", "CDN URL to download blobs from")
+	root.Flags().StringVar(&cdnUrl, "cdn-url", "https://git.centos.org/sources", "CDN URL to download blobs from. Simple URL follows default rocky/centos patterns. Can be customized using macros (see docs)")
 	root.Flags().StringVar(&singleTag, "single-tag", "", "If set, only this tag is imported")
 	root.Flags().BoolVar(&noDupMode, "no-dup-mode", false, "If enabled, skips already imported tags")
 	root.Flags().BoolVar(&moduleMode, "module-mode", false, "If enabled, imports a module instead of a package")
@@ -146,8 +146,8 @@ func main() {
 	root.Flags().StringVar(&basicPassword, "basic-password", "", "Basic auth password")
 	root.Flags().StringVar(&packageVersion, "package-version", "", "Package version to fetch")
 	root.Flags().StringVar(&packageRelease, "package-release", "", "Package release to fetch")
-	root.Flags().BoolVar(&taglessMode, "taglessmode", false, "Tagless mode:  If set, pull the latest commit from a branch, and determine version info from spec file (aka upstream versions aren't tagged)")
-	root.Flags().BoolVar(&altLookAside, "altlookaside", false, "If set, uses the new CentOS Stream lookaside pattern (https://<SITE_PREFIX>/<RPM_NAME>/<FILE_NAME>/<SHA_VERSION>/<SHA_SUM>/<FILE_NAME>)")
+	root.Flags().BoolVar(&taglessMode, "taglessmode", false, "Tagless mode:  If set, pull the latest commit from the branch and determine version numbers from spec file.  This is auto-tried if tags aren't found.")
+	root.Flags().StringVar(&cdn, "cdn", "", "CDN URL shortcuts for well-known distros, auto-assigns --cdn-url.  Valid values:  rocky8, rocky, fedora, centos, centos-stream.  Setting this overrides --cdn-url")
 
 	if err := root.Execute(); err != nil {
 		log.Fatal(err)

pkg/data/process.go

@@ -59,5 +59,5 @@ type ProcessData struct {
 	PackageVersion       string
 	PackageRelease       string
 	TaglessMode          bool
-	AltLookAside         bool
+	Cdn                  string
 }

pkg/modes/git.go

@@ -21,12 +21,15 @@
 package modes
 
 import (
+	"bytes"
 	"fmt"
 	"io/ioutil"
+	"log"
 	"net/http"
 	"path/filepath"
 	"sort"
 	"strings"
+	"text/template"
 	"time"
 
 	"github.com/go-git/go-git/v5/plumbing/transport"
@@ -46,6 +49,15 @@ type remoteTarget struct {
 	when   time.Time
 }
 
+// Struct to define the possible template values ( {{.Value}} in CDN URL strings:
+type Lookaside struct {
+	Name     string
+	Branch   string
+	Hash     string
+	Hashtype string
+	Filename string
+}
+
 type remoteTargetSlice []remoteTarget
 
 func (p remoteTargetSlice) Len() int {
@@ -341,44 +353,66 @@ func (g *GitMode) WriteSource(pd *data.ProcessData, md *data.ModeData) error {
 			} else {
 
 				url := ""
-				// Alternate lookaside logic:  if enabled, we pull from a new URL pattern
-				if !pd.AltLookAside {
-					url = fmt.Sprintf("%s/%s/%s/%s", pd.CdnUrl, md.Name, branchName, hash)
-				} else {
-					// We first need the hash algorithm based on length of hash:
-					hashType := "sha512"
-					switch len(hash) {
-					case 128:
-						hashType = "sha512"
-					case 64:
-						hashType = "sha256"
-					case 40:
-						hashType = "sha1"
-					case 32:
-						hashType = "md5"
-					}
-
-					// need the name of the file without "SOURCES/":
-					fileName := strings.Split(path, "/")[1]
 
-					// Alt. lookaside url is of the form: <cdn> / <name> / <filename> / <hashtype> / <hash> / <filename>
-					url = fmt.Sprintf("%s/%s/%s/%s/%s/%s", pd.CdnUrl, md.Name, fileName, hashType, hash, fileName)
+				// We need to figure out the hashtype for templating purposes:
+				hashType := "sha512"
+				switch len(hash) {
+				case 128:
+					hashType = "sha512"
+				case 64:
+					hashType = "sha256"
+				case 40:
+					hashType = "sha1"
+				case 32:
+					hashType = "md5"
 				}
 
-				pd.Log.Printf("downloading %s", url)
+				// need the name of the file without "SOURCES/":
+				fileName := strings.Split(path, "/")[1]
 
-				req, err := http.NewRequest("GET", url, nil)
-				if err != nil {
-					return fmt.Errorf("could not create new http request: %v", err)
+				// Feed our template info to ProcessUrl and transform to the real values: ( {{.Name}}, {{.Branch}}, {{.Hash}}, {{.Hashtype}}, {{.Filename}} )
+				url, hasTemplate := ProcessUrl(pd.CdnUrl, md.Name, branchName, hash, hashType, fileName)
+
+				var req *http.Request
+				var resp *http.Response
+
+				// Download the --cdn-url given, but *only* if it contains template strings ( {{.Name}} , {{.Hash}} , etc. )
+				// Otherwise we need to fall back to the traditional cdn-url patterns
+				if hasTemplate {
+					pd.Log.Printf("downloading %s", url)
+
+					req, err := http.NewRequest("GET", url, nil)
+					if err != nil {
+						return fmt.Errorf("could not create new http request: %v", err)
+					}
+					req.Header.Set("Accept-Encoding", "*")
+
+					resp, err = client.Do(req)
+					if err != nil {
+						return fmt.Errorf("could not download dist-git file: %v", err)
+					}
 				}
-				req.Header.Set("Accept-Encoding", "*")
 
-				resp, err := client.Do(req)
-				if err != nil {
-					return fmt.Errorf("could not download dist-git file: %v", err)
+				// Default cdn-url:  If we don't have a templated download string, try the default <SITE>/<PKG>/<BRANCH>/<HASH> pattern:
+				if resp == nil || resp.StatusCode != http.StatusOK {
+					url = fmt.Sprintf("%s/%s/%s/%s", pd.CdnUrl, md.Name, branchName, hash)
+					pd.Log.Printf("Attempting default URL: %s", url)
+					req, err = http.NewRequest("GET", url, nil)
+					if err != nil {
+						return fmt.Errorf("could not create new http request: %v", err)
+					}
+					req.Header.Set("Accept-Encoding", "*")
+					resp, err = client.Do(req)
+					if err != nil {
+						return fmt.Errorf("could not download dist-git file: %v", err)
+					}
 				}
-				if resp.StatusCode != http.StatusOK {
+
+				// If the default URL fails, we have one more pattern to try.  The simple <SITE>/<HASH> pattern
+				// If this one fails, we are truly lost, and have to bail out w/ an error:
+				if resp == nil || resp.StatusCode != http.StatusOK {
 					url = fmt.Sprintf("%s/%s", pd.CdnUrl, hash)
+					pd.Log.Printf("Attempting 2nd fallback URL: %s", url)
 					req, err = http.NewRequest("GET", url, nil)
 					if err != nil {
 						return fmt.Errorf("could not create new http request: %v", err)
@@ -458,3 +492,24 @@ func (g *GitMode) ImportName(pd *data.ProcessData, md *data.ModeData) string {
 
 	return strings.Replace(strings.TrimPrefix(md.TagBranch, "refs/heads/"), "%", "_", -1)
 }
+
+// Given a cdnUrl string as input, return same string, but with substituted
+// template values ( {{.Name}} , {{.Hash}}, {{.Filename}}, etc. )
+func ProcessUrl(cdnUrl string, name string, branch string, hash string, hashtype string, filename string) (string, bool) {
+	tmpUrl := Lookaside{name, branch, hash, hashtype, filename}
+
+	// If we run into trouble with our template parsing, we'll just return the cdnUrl, exactly as we found it
+	tmpl, err := template.New("").Parse(cdnUrl)
+	if err != nil {
+		return cdnUrl, false
+	}
+
+	var result bytes.Buffer
+	err = tmpl.Execute(&result, tmpUrl)
+	if err != nil {
+		log.Fatalf("ERROR: Could not process CDN URL template(s) from URL string: %s\n", cdnUrl)
+	}
+
+	return result.String(), true
+
+}