doi: add new doi backend

Add a new backend to support mounting datasets published with a digital
object identifier (DOI).

backend/all/all.go

@@ -14,6 +14,7 @@ import (
 	_ "github.com/rclone/rclone/backend/combine"
 	_ "github.com/rclone/rclone/backend/compress"
 	_ "github.com/rclone/rclone/backend/crypt"
+	_ "github.com/rclone/rclone/backend/doi"
 	_ "github.com/rclone/rclone/backend/drive"
 	_ "github.com/rclone/rclone/backend/dropbox"
 	_ "github.com/rclone/rclone/backend/fichier"

backend/doi/api/dataversetypes.go

@@ -0,0 +1,38 @@
+// Type definitions specific to Dataverse
+
+package api
+
+// DataverseDatasetResponse is returned by the Dataverse dataset API
+type DataverseDatasetResponse struct {
+	Status string           `json:"status"`
+	Data   DataverseDataset `json:"data"`
+}
+
+// DataverseDataset is the representation of a dataset
+type DataverseDataset struct {
+	LatestVersion DataverseDatasetVersion `json:"latestVersion"`
+}
+
+// DataverseDatasetVersion is the representation of a dataset version
+type DataverseDatasetVersion struct {
+	LastUpdateTime string          `json:"lastUpdateTime"`
+	Files          []DataverseFile `json:"files"`
+}
+
+// DataverseFile is the representation of a file found in a dataset
+type DataverseFile struct {
+	DirectoryLabel string            `json:"directoryLabel"`
+	DataFile       DataverseDataFile `json:"dataFile"`
+}
+
+// DataverseDataFile represents file metadata details
+type DataverseDataFile struct {
+	ID                 int64  `json:"id"`
+	Filename           string `json:"filename"`
+	ContentType        string `json:"contentType"`
+	FileSize           int64  `json:"filesize"`
+	OriginalFileFormat string `json:"originalFileFormat"`
+	OriginalFileSize   int64  `json:"originalFileSize"`
+	OriginalFileName   string `json:"originalFileName"`
+	MD5                string `json:"md5"`
+}

backend/doi/api/inveniotypes.go

@@ -0,0 +1,33 @@
+// Type definitions specific to InvenioRDM
+
+package api
+
+// InvenioRecordResponse is the representation of a record stored in InvenioRDM
+type InvenioRecordResponse struct {
+	Links InvenioRecordResponseLinks `json:"links"`
+}
+
+// InvenioRecordResponseLinks represents a record's links
+type InvenioRecordResponseLinks struct {
+	Self string `json:"self"`
+}
+
+// InvenioFilesResponse is the representation of a record's files
+type InvenioFilesResponse struct {
+	Entries []InvenioFilesResponseEntry `json:"entries"`
+}
+
+// InvenioFilesResponseEntry is the representation of a file entry
+type InvenioFilesResponseEntry struct {
+	Key      string                         `json:"key"`
+	Checksum string                         `json:"checksum"`
+	Size     int64                          `json:"size"`
+	Updated  string                         `json:"updated"`
+	MimeType string                         `json:"mimetype"`
+	Links    InvenioFilesResponseEntryLinks `json:"links"`
+}
+
+// InvenioFilesResponseEntryLinks represents file links details
+type InvenioFilesResponseEntryLinks struct {
+	Content string `json:"content"`
+}

backend/doi/api/types.go

@@ -0,0 +1,26 @@
+// Package api has general type definitions for doi
+package api
+
+// DoiResolverResponse is returned by the DOI resolver API
+//
+// Reference: https://www.doi.org/the-identifier/resources/factsheets/doi-resolution-documentation
+type DoiResolverResponse struct {
+	ResponseCode int                        `json:"responseCode"`
+	Handle       string                     `json:"handle"`
+	Values       []DoiResolverResponseValue `json:"values"`
+}
+
+// DoiResolverResponseValue is a single handle record value
+type DoiResolverResponseValue struct {
+	Index     int                          `json:"index"`
+	Type      string                       `json:"type"`
+	Data      DoiResolverResponseValueData `json:"data"`
+	TTL       int                          `json:"ttl"`
+	Timestamp string                       `json:"timestamp"`
+}
+
+// DoiResolverResponseValueData is the data held in a handle value
+type DoiResolverResponseValueData struct {
+	Format string `json:"format"`
+	Value  any    `json:"value"`
+}

backend/doi/dataverse.go

@@ -0,0 +1,112 @@
+// Implementation for Dataverse
+
+package doi
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+	"path"
+	"strings"
+	"time"
+
+	"github.com/rclone/rclone/backend/doi/api"
+	"github.com/rclone/rclone/fs"
+	"github.com/rclone/rclone/lib/rest"
+)
+
+// Returns true if resolvedURL is likely a DOI hosted on a Dataverse intallation
+func activateDataverse(resolvedURL *url.URL) (isActive bool) {
+	queryValues := resolvedURL.Query()
+	persistentID := queryValues.Get("persistentId")
+	return persistentID != ""
+}
+
+// Resolve the main API endpoint for a DOI hosted on a Dataverse installation
+func resolveDataverseEndpoint(resolvedURL *url.URL) (provider Provider, endpoint *url.URL, err error) {
+	queryValues := resolvedURL.Query()
+	persistentID := queryValues.Get("persistentId")
+
+	query := url.Values{}
+	query.Add("persistentId", persistentID)
+	endpointURL := resolvedURL.ResolveReference(&url.URL{Path: "/api/datasets/:persistentId/", RawQuery: query.Encode()})
+
+	return Dataverse, endpointURL, nil
+}
+
+// dataverseProvider implements the doiProvider interface for Dataverse installations
+type dataverseProvider struct {
+	f *Fs
+}
+
+// ListEntries returns the full list of entries found at the remote, regardless of root
+func (dp *dataverseProvider) ListEntries(ctx context.Context) (entries []*Object, err error) {
+	// Use the cache if populated
+	cachedEntries, found := dp.f.cache.GetMaybe("files")
+	if found {
+		parsedEntries, ok := cachedEntries.([]Object)
+		if ok {
+			for _, entry := range parsedEntries {
+				newEntry := entry
+				entries = append(entries, &newEntry)
+			}
+			return entries, nil
+		}
+	}
+
+	filesURL := dp.f.endpoint
+	var res *http.Response
+	var result api.DataverseDatasetResponse
+	opts := rest.Opts{
+		Method:     "GET",
+		Path:       strings.TrimLeft(filesURL.EscapedPath(), "/"),
+		Parameters: filesURL.Query(),
+	}
+	err = dp.f.pacer.Call(func() (bool, error) {
+		res, err = dp.f.srv.CallJSON(ctx, &opts, nil, &result)
+		return shouldRetry(ctx, res, err)
+	})
+	if err != nil {
+		return nil, fmt.Errorf("readDir failed: %w", err)
+	}
+	modTime, modTimeErr := time.Parse(time.RFC3339, result.Data.LatestVersion.LastUpdateTime)
+	if modTimeErr != nil {
+		fs.Logf(dp.f, "error: could not parse last update time %v", modTimeErr)
+		modTime = timeUnset
+	}
+	for _, file := range result.Data.LatestVersion.Files {
+		contentURLPath := fmt.Sprintf("/api/access/datafile/%d", file.DataFile.ID)
+		query := url.Values{}
+		query.Add("format", "original")
+		contentURL := dp.f.endpoint.ResolveReference(&url.URL{Path: contentURLPath, RawQuery: query.Encode()})
+		entry := &Object{
+			fs:          dp.f,
+			remote:      path.Join(file.DirectoryLabel, file.DataFile.Filename),
+			contentURL:  contentURL.String(),
+			size:        file.DataFile.FileSize,
+			modTime:     modTime,
+			md5:         file.DataFile.MD5,
+			contentType: file.DataFile.ContentType,
+		}
+		if file.DataFile.OriginalFileName != "" {
+			entry.remote = path.Join(file.DirectoryLabel, file.DataFile.OriginalFileName)
+			entry.size = file.DataFile.OriginalFileSize
+			entry.contentType = file.DataFile.OriginalFileFormat
+		}
+		entries = append(entries, entry)
+	}
+	// Populate the cache
+	cacheEntries := []Object{}
+	for _, entry := range entries {
+		cacheEntries = append(cacheEntries, *entry)
+	}
+	dp.f.cache.Put("files", cacheEntries)
+	return entries, nil
+}
+
+func newDataverseProvider(f *Fs) doiProvider {
+	return &dataverseProvider{
+		f: f,
+	}
+}

backend/doi/doi.go

@@ -0,0 +1,649 @@
+// Package doi provides a filesystem interface for digital objects identified by DOIs.
+//
+// See: https://www.doi.org/the-identifier/what-is-a-doi/
+package doi
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"path"
+	"strings"
+	"time"
+
+	"github.com/rclone/rclone/backend/doi/api"
+	"github.com/rclone/rclone/fs"
+	"github.com/rclone/rclone/fs/config/configmap"
+	"github.com/rclone/rclone/fs/config/configstruct"
+	"github.com/rclone/rclone/fs/fserrors"
+	"github.com/rclone/rclone/fs/fshttp"
+	"github.com/rclone/rclone/fs/hash"
+	"github.com/rclone/rclone/lib/cache"
+	"github.com/rclone/rclone/lib/pacer"
+	"github.com/rclone/rclone/lib/rest"
+)
+
+const (
+	// the URL of the DOI resolver
+	//
+	// Reference: https://www.doi.org/the-identifier/resources/factsheets/doi-resolution-documentation
+	doiResolverAPIURL = "https://doi.org/api"
+	minSleep          = 10 * time.Millisecond
+	maxSleep          = 2 * time.Second
+	decayConstant     = 2 // bigger for slower decay, exponential
+)
+
+var (
+	errorReadOnly = errors.New("doi remotes are read only")
+	timeUnset     = time.Unix(0, 0)
+)
+
+func init() {
+	fsi := &fs.RegInfo{
+		Name:        "doi",
+		Description: "DOI datasets",
+		NewFs:       NewFs,
+		CommandHelp: commandHelp,
+		Options: []fs.Option{{
+			Name:     "doi",
+			Help:     "The DOI or the doi.org URL.",
+			Required: true,
+		}, {
+			Name: fs.ConfigProvider,
+			Help: `DOI provider.
+
+The DOI provider can be set when rclone does not automatically recognize a supported DOI provider.`,
+			Examples: []fs.OptionExample{
+				{
+					Value: "auto",
+					Help:  "Auto-detect provider",
+				},
+				{
+					Value: string(Zenodo),
+					Help:  "Zenodo",
+				}, {
+					Value: string(Dataverse),
+					Help:  "Dataverse",
+				}, {
+					Value: string(Invenio),
+					Help:  "Invenio",
+				}},
+			Required: false,
+			Advanced: true,
+		}, {
+			Name: "doi_resolver_api_url",
+			Help: `The URL of the DOI resolver API to use.
+
+The DOI resolver can be set for testing or for cases when the the canonical DOI resolver API cannot be used.
+
+Defaults to "https://doi.org/api".`,
+			Required: false,
+			Advanced: true,
+		}},
+	}
+	fs.Register(fsi)
+}
+
+// Provider defines the type of provider hosting the DOI
+type Provider string
+
+const (
+	// Zenodo provider, see https://zenodo.org
+	Zenodo Provider = "zenodo"
+	// Dataverse provider, see https://dataverse.harvard.edu
+	Dataverse Provider = "dataverse"
+	// Invenio provider, see https://inveniordm.docs.cern.ch
+	Invenio Provider = "invenio"
+)
+
+// Options defines the configuration for this backend
+type Options struct {
+	Doi               string `config:"doi"`                  // The DOI, a digital identifier of an object, usually a dataset
+	Provider          string `config:"provider"`             // The DOI provider
+	DoiResolverAPIURL string `config:"doi_resolver_api_url"` // The URL of the DOI resolver API to use.
+}
+
+// Fs stores the interface to the remote HTTP files
+type Fs struct {
+	name        string         // name of this remote
+	root        string         // the path we are working on
+	provider    Provider       // the DOI provider
+	doiProvider doiProvider    // the interface used to interact with the DOI provider
+	features    *fs.Features   // optional features
+	opt         Options        // options for this backend
+	ci          *fs.ConfigInfo // global config
+	endpoint    *url.URL       // the main API endpoint for this remote
+	endpointURL string         // endpoint as a string
+	srv         *rest.Client   // the connection to the server
+	pacer       *fs.Pacer      // pacer for API calls
+	cache       *cache.Cache   // a cache for the remote metadata
+}
+
+// Object is a remote object that has been stat'd (so it exists, but is not necessarily open for reading)
+type Object struct {
+	fs          *Fs       // what this object is part of
+	remote      string    // the remote path
+	contentURL  string    // the URL where the contents of the file can be downloaded
+	size        int64     // size of the object
+	modTime     time.Time // modification time of the object
+	contentType string    // content type of the object
+	md5         string    // MD5 hash of the object content
+}
+
+// doiProvider is the interface used to list objects in a DOI
+type doiProvider interface {
+	// ListEntries returns the full list of entries found at the remote, regardless of root
+	ListEntries(ctx context.Context) (entries []*Object, err error)
+}
+
+// Parse the input string as a DOI
+// Examples:
+// 10.1000/182 -> 10.1000/182
+// https://doi.org/10.1000/182 -> 10.1000/182
+// doi:10.1000/182 -> 10.1000/182
+func parseDoi(doi string) string {
+	doiURL, err := url.Parse(doi)
+	if err != nil {
+		return doi
+	}
+	if doiURL.Scheme == "doi" {
+		return strings.TrimLeft(strings.TrimPrefix(doi, "doi:"), "/")
+	}
+	if strings.HasSuffix(doiURL.Hostname(), "doi.org") {
+		return strings.TrimLeft(doiURL.Path, "/")
+	}
+	return doi
+}
+
+// Resolve a DOI to a URL
+// Reference: https://www.doi.org/the-identifier/resources/factsheets/doi-resolution-documentation
+func resolveDoiURL(ctx context.Context, srv *rest.Client, pacer *fs.Pacer, opt *Options) (doiURL *url.URL, err error) {
+	resolverURL := opt.DoiResolverAPIURL
+	if resolverURL == "" {
+		resolverURL = doiResolverAPIURL
+	}
+
+	var result api.DoiResolverResponse
+	params := url.Values{}
+	params.Add("index", "1")
+	opts := rest.Opts{
+		Method:     "GET",
+		RootURL:    resolverURL,
+		Path:       "/handles/" + opt.Doi,
+		Parameters: params,
+	}
+	err = pacer.Call(func() (bool, error) {
+		res, err := srv.CallJSON(ctx, &opts, nil, &result)
+		return shouldRetry(ctx, res, err)
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	if result.ResponseCode != 1 {
+		return nil, fmt.Errorf("could not resolve DOI (error code %d)", result.ResponseCode)
+	}
+	resolvedURLStr := ""
+	for _, value := range result.Values {
+		if value.Type == "URL" && value.Data.Format == "string" {
+			valueStr, ok := value.Data.Value.(string)
+			if !ok {
+				return nil, fmt.Errorf("could not resolve DOI (incorrect response format)")
+			}
+			resolvedURLStr = valueStr
+		}
+	}
+	resolvedURL, err := url.Parse(resolvedURLStr)
+	if err != nil {
+		return nil, err
+	}
+	return resolvedURL, nil
+}
+
+// Resolve the passed configuration into a provider and enpoint
+func resolveEndpoint(ctx context.Context, srv *rest.Client, pacer *fs.Pacer, opt *Options) (provider Provider, endpoint *url.URL, err error) {
+	resolvedURL, err := resolveDoiURL(ctx, srv, pacer, opt)
+	if err != nil {
+		return "", nil, err
+	}
+
+	switch opt.Provider {
+	case string(Dataverse):
+		return resolveDataverseEndpoint(resolvedURL)
+	case string(Invenio):
+		return resolveInvenioEndpoint(ctx, srv, pacer, resolvedURL)
+	case string(Zenodo):
+		return resolveZenodoEndpoint(ctx, srv, pacer, resolvedURL, opt.Doi)
+	}
+
+	hostname := strings.ToLower(resolvedURL.Hostname())
+	if hostname == "dataverse.harvard.edu" || activateDataverse(resolvedURL) {
+		return resolveDataverseEndpoint(resolvedURL)
+	}
+	if hostname == "zenodo.org" || strings.HasSuffix(hostname, ".zenodo.org") {
+		return resolveZenodoEndpoint(ctx, srv, pacer, resolvedURL, opt.Doi)
+	}
+	if activateInvenio(ctx, srv, pacer, resolvedURL) {
+		return resolveInvenioEndpoint(ctx, srv, pacer, resolvedURL)
+	}
+
+	return "", nil, fmt.Errorf("provider '%s' is not supported", resolvedURL.Hostname())
+}
+
+// Make the http connection from the passed options
+func (f *Fs) httpConnection(ctx context.Context, opt *Options) (isFile bool, err error) {
+	provider, endpoint, err := resolveEndpoint(ctx, f.srv, f.pacer, opt)
+	if err != nil {
+		return false, err
+	}
+
+	// Update f with the new parameters
+	f.srv.SetRoot(endpoint.ResolveReference(&url.URL{Path: "/"}).String())
+	f.endpoint = endpoint
+	f.endpointURL = endpoint.String()
+	f.provider = provider
+	f.opt.Provider = string(provider)
+
+	switch f.provider {
+	case Dataverse:
+		f.doiProvider = newDataverseProvider(f)
+	case Invenio, Zenodo:
+		f.doiProvider = newInvenioProvider(f)
+	default:
+		return false, fmt.Errorf("provider type '%s' not supported", f.provider)
+	}
+
+	// Determine if the root is a file
+	entries, err := f.doiProvider.ListEntries(ctx)
+	if err != nil {
+		return false, err
+	}
+	for _, entry := range entries {
+		if entry.remote == f.root {
+			isFile = true
+			break
+		}
+	}
+	return isFile, nil
+}
+
+// retryErrorCodes is a slice of error codes that we will retry
+var retryErrorCodes = []int{
+	429, // Too Many Requests.
+	500, // Internal Server Error
+	502, // Bad Gateway
+	503, // Service Unavailable
+	504, // Gateway Timeout
+	509, // Bandwidth Limit Exceeded
+}
+
+// shouldRetry returns a boolean as to whether this res and err
+// deserve to be retried. It returns the err as a convenience.
+func shouldRetry(ctx context.Context, res *http.Response, err error) (bool, error) {
+	if fserrors.ContextError(ctx, &err) {
+		return false, err
+	}
+	return fserrors.ShouldRetry(err) || fserrors.ShouldRetryHTTP(res, retryErrorCodes), err
+}
+
+// NewFs creates a new Fs object from the name and root. It connects to
+// the host specified in the config file.
+func NewFs(ctx context.Context, name, root string, m configmap.Mapper) (fs.Fs, error) {
+	root = strings.Trim(root, "/")
+
+	// Parse config into Options struct
+	opt := new(Options)
+	err := configstruct.Set(m, opt)
+	if err != nil {
+		return nil, err
+	}
+	opt.Doi = parseDoi(opt.Doi)
+
+	client := fshttp.NewClient(ctx)
+	ci := fs.GetConfig(ctx)
+	f := &Fs{
+		name:  name,
+		root:  root,
+		opt:   *opt,
+		ci:    ci,
+		srv:   rest.NewClient(client),
+		pacer: fs.NewPacer(ctx, pacer.NewDefault(pacer.MinSleep(minSleep), pacer.MaxSleep(maxSleep), pacer.DecayConstant(decayConstant))),
+		cache: cache.New(),
+	}
+	f.features = (&fs.Features{
+		CanHaveEmptyDirectories: true,
+	}).Fill(ctx, f)
+
+	isFile, err := f.httpConnection(ctx, opt)
+	if err != nil {
+		return nil, err
+	}
+
+	if isFile {
+		// return an error with an fs which points to the parent
+		newRoot := path.Dir(f.root)
+		if newRoot == "." {
+			newRoot = ""
+		}
+		f.root = newRoot
+		return f, fs.ErrorIsFile
+	}
+
+	return f, nil
+}
+
+// Name returns the configured name of the file system
+func (f *Fs) Name() string {
+	return f.name
+}
+
+// Root returns the root for the filesystem
+func (f *Fs) Root() string {
+	return f.root
+}
+
+// String returns the URL for the filesystem
+func (f *Fs) String() string {
+	return fmt.Sprintf("DOI %s", f.opt.Doi)
+}
+
+// Features returns the optional features of this Fs
+func (f *Fs) Features() *fs.Features {
+	return f.features
+}
+
+// Precision is the remote http file system's modtime precision, which we have no way of knowing. We estimate at 1s
+func (f *Fs) Precision() time.Duration {
+	return time.Second
+}
+
+// Hashes returns hash.HashNone to indicate remote hashing is unavailable
+func (f *Fs) Hashes() hash.Set {
+	return hash.Set(hash.MD5)
+	// return hash.Set(hash.None)
+}
+
+// Mkdir makes the root directory of the Fs object
+func (f *Fs) Mkdir(ctx context.Context, dir string) error {
+	return errorReadOnly
+}
+
+// Remove a remote http file object
+func (o *Object) Remove(ctx context.Context) error {
+	return errorReadOnly
+}
+
+// Rmdir removes the root directory of the Fs object
+func (f *Fs) Rmdir(ctx context.Context, dir string) error {
+	return errorReadOnly
+}
+
+// NewObject creates a new remote http file object
+func (f *Fs) NewObject(ctx context.Context, remote string) (fs.Object, error) {
+	entries, err := f.doiProvider.ListEntries(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	remoteFullPath := remote
+	if f.root != "" {
+		remoteFullPath = path.Join(f.root, remote)
+	}
+
+	for _, entry := range entries {
+		if entry.Remote() == remoteFullPath {
+			return entry, nil
+		}
+	}
+
+	return nil, fs.ErrorObjectNotFound
+}
+
+// List the objects and directories in dir into entries.  The
+// entries can be returned in any order but should be for a
+// complete directory.
+//
+// dir should be "" to list the root, and should not have
+// trailing slashes.
+//
+// This should return ErrDirNotFound if the directory isn't
+// found.
+func (f *Fs) List(ctx context.Context, dir string) (entries fs.DirEntries, err error) {
+	fileEntries, err := f.doiProvider.ListEntries(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("error listing %q: %w", dir, err)
+	}
+
+	fullDir := path.Join(f.root, dir)
+	if fullDir != "" {
+		fullDir += "/"
+	}
+
+	dirPaths := map[string]bool{}
+	for _, entry := range fileEntries {
+		// First, filter out files not in `fullDir`
+		if !strings.HasPrefix(entry.remote, fullDir) {
+			continue
+		}
+		// Then, find entries in subfolers
+		remotePath := entry.remote
+		if fullDir != "" {
+			remotePath = strings.TrimLeft(strings.TrimPrefix(remotePath, fullDir), "/")
+		}
+		parts := strings.SplitN(remotePath, "/", 2)
+		if len(parts) == 1 {
+			newEntry := *entry
+			newEntry.remote = path.Join(dir, remotePath)
+			entries = append(entries, &newEntry)
+		} else {
+			dirPaths[path.Join(dir, parts[0])] = true
+		}
+	}
+
+	for dirPath := range dirPaths {
+		entry := fs.NewDir(dirPath, time.Time{})
+		entries = append(entries, entry)
+	}
+
+	return entries, nil
+}
+
+// Put in to the remote path with the modTime given of the given size
+//
+// May create the object even if it returns an error - if so
+// will return the object and the error, otherwise will return
+// nil and the error
+func (f *Fs) Put(ctx context.Context, in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) (fs.Object, error) {
+	return nil, errorReadOnly
+}
+
+// PutStream uploads to the remote path with the modTime given of indeterminate size
+func (f *Fs) PutStream(ctx context.Context, in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) (fs.Object, error) {
+	return nil, errorReadOnly
+}
+
+// Fs is the filesystem this remote http file object is located within
+func (o *Object) Fs() fs.Info {
+	return o.fs
+}
+
+// String returns the URL to the remote HTTP file
+func (o *Object) String() string {
+	if o == nil {
+		return "<nil>"
+	}
+	return o.remote
+}
+
+// Remote the name of the remote HTTP file, relative to the fs root
+func (o *Object) Remote() string {
+	return o.remote
+}
+
+// Hash returns "" since HTTP (in Go or OpenSSH) doesn't support remote calculation of hashes
+func (o *Object) Hash(ctx context.Context, t hash.Type) (string, error) {
+	if t != hash.MD5 {
+		return "", hash.ErrUnsupported
+	}
+	return o.md5, nil
+}
+
+// Size returns the size in bytes of the remote http file
+func (o *Object) Size() int64 {
+	return o.size
+}
+
+// ModTime returns the modification time of the remote http file
+func (o *Object) ModTime(ctx context.Context) time.Time {
+	return o.modTime
+}
+
+// SetModTime sets the modification and access time to the specified time
+//
+// it also updates the info field
+func (o *Object) SetModTime(ctx context.Context, modTime time.Time) error {
+	return errorReadOnly
+}
+
+// Storable returns whether the remote http file is a regular file (not a directory, symbolic link, block device, character device, named pipe, etc.)
+func (o *Object) Storable() bool {
+	return true
+}
+
+// Open a remote http file object for reading. Seek is supported
+func (o *Object) Open(ctx context.Context, options ...fs.OpenOption) (in io.ReadCloser, err error) {
+	fs.FixRangeOption(options, o.size)
+	opts := rest.Opts{
+		Method:  "GET",
+		RootURL: o.contentURL,
+		Options: options,
+	}
+	var res *http.Response
+	err = o.fs.pacer.Call(func() (bool, error) {
+		res, err = o.fs.srv.Call(ctx, &opts)
+		return shouldRetry(ctx, res, err)
+	})
+	if err != nil {
+		return nil, fmt.Errorf("Open failed: %w", err)
+	}
+
+	// Handle non-compliant redirects
+	if res.Header.Get("Location") != "" {
+		newURL, err := res.Location()
+		if err == nil {
+			opts.RootURL = newURL.String()
+			err = o.fs.pacer.Call(func() (bool, error) {
+				res, err = o.fs.srv.Call(ctx, &opts)
+				return shouldRetry(ctx, res, err)
+			})
+			if err != nil {
+				return nil, fmt.Errorf("Open failed: %w", err)
+			}
+		}
+	}
+
+	return res.Body, nil
+}
+
+// Update in to the object with the modTime given of the given size
+func (o *Object) Update(ctx context.Context, in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) error {
+	return errorReadOnly
+}
+
+// MimeType of an Object if known, "" otherwise
+func (o *Object) MimeType(ctx context.Context) string {
+	return o.contentType
+}
+
+var commandHelp = []fs.CommandHelp{{
+	Name:  "metadata",
+	Short: "Show metadata about the DOI.",
+	Long: `This command returns a JSON object with some information about the DOI.
+
+    rclone backend medatadata doi: 
+
+It returns a JSON object representing metadata about the DOI.
+`,
+}, {
+	Name:  "set",
+	Short: "Set command for updating the config parameters.",
+	Long: `This set command can be used to update the config parameters
+for a running doi backend.
+
+Usage Examples:
+
+    rclone backend set doi: [-o opt_name=opt_value] [-o opt_name2=opt_value2]
+    rclone rc backend/command command=set fs=doi: [-o opt_name=opt_value] [-o opt_name2=opt_value2]
+    rclone rc backend/command command=set fs=doi: -o doi=NEW_DOI
+
+The option keys are named as they are in the config file.
+
+This rebuilds the connection to the doi backend when it is called with
+the new parameters. Only new parameters need be passed as the values
+will default to those currently in use.
+
+It doesn't return anything.
+`,
+}}
+
+// Command the backend to run a named command
+//
+// The command run is name
+// args may be used to read arguments from
+// opts may be used to read optional arguments from
+//
+// The result should be capable of being JSON encoded
+// If it is a string or a []string it will be shown to the user
+// otherwise it will be JSON encoded and shown to the user like that
+func (f *Fs) Command(ctx context.Context, name string, arg []string, opt map[string]string) (out interface{}, err error) {
+	switch name {
+	case "metadata":
+		return f.ShowMetadata(ctx)
+	case "set":
+		newOpt := f.opt
+		err := configstruct.Set(configmap.Simple(opt), &newOpt)
+		if err != nil {
+			return nil, fmt.Errorf("reading config: %w", err)
+		}
+		_, err = f.httpConnection(ctx, &newOpt)
+		if err != nil {
+			return nil, fmt.Errorf("updating session: %w", err)
+		}
+		f.opt = newOpt
+		keys := []string{}
+		for k := range opt {
+			keys = append(keys, k)
+		}
+		fs.Logf(f, "Updated config values: %s", strings.Join(keys, ", "))
+		return nil, nil
+	default:
+		return nil, fs.ErrorCommandNotFound
+	}
+}
+
+// ShowMetadata returns some metadata about the corresponding DOI
+func (f *Fs) ShowMetadata(ctx context.Context) (metadata interface{}, err error) {
+	doiURL, err := url.Parse("https://doi.org/" + f.opt.Doi)
+	if err != nil {
+		return nil, err
+	}
+
+	info := map[string]any{}
+	info["DOI"] = f.opt.Doi
+	info["URL"] = doiURL.String()
+	info["metadataURL"] = f.endpointURL
+	info["provider"] = f.provider
+	return info, nil
+}
+
+// Check the interfaces are satisfied
+var (
+	_ fs.Fs          = (*Fs)(nil)
+	_ fs.PutStreamer = (*Fs)(nil)
+	_ fs.Commander   = (*Fs)(nil)
+	_ fs.Object      = (*Object)(nil)
+	_ fs.MimeTyper   = (*Object)(nil)
+)

backend/doi/doi_internal_test.go

@@ -0,0 +1,260 @@
+package doi
+
+import (
+	"context"
+	"crypto/md5"
+	"encoding/hex"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"sort"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/rclone/rclone/backend/doi/api"
+	"github.com/rclone/rclone/fs"
+	"github.com/rclone/rclone/fs/config/configmap"
+	"github.com/rclone/rclone/fs/hash"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+var remoteName = "TestDoi"
+
+func TestParseDoi(t *testing.T) {
+	// 10.1000/182 -> 10.1000/182
+	doi := "10.1000/182"
+	parsed := parseDoi(doi)
+	assert.Equal(t, "10.1000/182", parsed)
+
+	// https://doi.org/10.1000/182 -> 10.1000/182
+	doi = "https://doi.org/10.1000/182"
+	parsed = parseDoi(doi)
+	assert.Equal(t, "10.1000/182", parsed)
+
+	// https://dx.doi.org/10.1000/182 -> 10.1000/182
+	doi = "https://dxdoi.org/10.1000/182"
+	parsed = parseDoi(doi)
+	assert.Equal(t, "10.1000/182", parsed)
+
+	// doi:10.1000/182 -> 10.1000/182
+	doi = "doi:10.1000/182"
+	parsed = parseDoi(doi)
+	assert.Equal(t, "10.1000/182", parsed)
+
+	// doi://10.1000/182 -> 10.1000/182
+	doi = "doi://10.1000/182"
+	parsed = parseDoi(doi)
+	assert.Equal(t, "10.1000/182", parsed)
+}
+
+// prepareMockDoiResolverServer prepares a test server to resolve DOIs
+func prepareMockDoiResolverServer(t *testing.T, resolvedURL string) (doiResolverAPIURL string) {
+	mux := http.NewServeMux()
+
+	// Handle requests for resolving DOIs
+	mux.HandleFunc("GET /api/handles/{handle...}", func(w http.ResponseWriter, r *http.Request) {
+		// Check that we are resolving a DOI
+		handle := strings.TrimPrefix(r.URL.Path, "/api/handles/")
+		assert.NotEmpty(t, handle)
+		index := r.URL.Query().Get("index")
+		assert.Equal(t, "1", index)
+
+		// Return the most basic response
+		result := api.DoiResolverResponse{
+			ResponseCode: 1,
+			Handle:       handle,
+			Values: []api.DoiResolverResponseValue{
+				{
+					Index: 1,
+					Type:  "URL",
+					Data: api.DoiResolverResponseValueData{
+						Format: "string",
+						Value:  resolvedURL,
+					},
+				},
+			},
+		}
+		resultBytes, err := json.Marshal(result)
+		require.NoError(t, err)
+		w.Header().Add("Content-Type", "application/json")
+		_, err = w.Write(resultBytes)
+		require.NoError(t, err)
+	})
+
+	// Make the test server
+	ts := httptest.NewServer(mux)
+
+	// Close the server at the end of the test
+	t.Cleanup(ts.Close)
+
+	return ts.URL + "/api"
+}
+
+func md5Sum(text string) string {
+	hash := md5.Sum([]byte(text))
+	return hex.EncodeToString(hash[:])
+}
+
+// prepareMockZenodoServer prepares a test server that mocks Zenodo.org
+func prepareMockZenodoServer(t *testing.T, files map[string]string) *httptest.Server {
+	mux := http.NewServeMux()
+
+	// Handle requests for a single record
+	mux.HandleFunc("GET /api/records/{recordID...}", func(w http.ResponseWriter, r *http.Request) {
+		// Check that we are returning data about a single record
+		recordID := strings.TrimPrefix(r.URL.Path, "/api/records/")
+		assert.NotEmpty(t, recordID)
+
+		// Return the most basic response
+		selfURL, err := url.Parse("http://" + r.Host)
+		require.NoError(t, err)
+		selfURL = selfURL.JoinPath(r.URL.String())
+		result := api.InvenioRecordResponse{
+			Links: api.InvenioRecordResponseLinks{
+				Self: selfURL.String(),
+			},
+		}
+		resultBytes, err := json.Marshal(result)
+		require.NoError(t, err)
+		w.Header().Add("Content-Type", "application/json")
+		_, err = w.Write(resultBytes)
+		require.NoError(t, err)
+	})
+	// Handle requests for listing files in a record
+	mux.HandleFunc("GET /api/records/{record}/files", func(w http.ResponseWriter, r *http.Request) {
+		// Return the most basic response
+		filesBaseURL, err := url.Parse("http://" + r.Host)
+		require.NoError(t, err)
+		filesBaseURL = filesBaseURL.JoinPath("/api/files/")
+
+		entries := []api.InvenioFilesResponseEntry{}
+		for filename, contents := range files {
+			entries = append(entries,
+				api.InvenioFilesResponseEntry{
+					Key:      filename,
+					Checksum: md5Sum(contents),
+					Size:     int64(len(contents)),
+					Updated:  time.Now().UTC().Format(time.RFC3339),
+					MimeType: "text/plain; charset=utf-8",
+					Links: api.InvenioFilesResponseEntryLinks{
+						Content: filesBaseURL.JoinPath(filename).String(),
+					},
+				},
+			)
+		}
+
+		result := api.InvenioFilesResponse{
+			Entries: entries,
+		}
+		resultBytes, err := json.Marshal(result)
+		require.NoError(t, err)
+		w.Header().Add("Content-Type", "application/json")
+		_, err = w.Write(resultBytes)
+		require.NoError(t, err)
+	})
+	// Handle requests for file contents
+	mux.HandleFunc("/api/files/{file}", func(w http.ResponseWriter, r *http.Request) {
+		// Check that we are returning the contents of a file
+		filename := strings.TrimPrefix(r.URL.Path, "/api/files/")
+		assert.NotEmpty(t, filename)
+		contents, found := files[filename]
+		if !found {
+			w.WriteHeader(404)
+			return
+		}
+
+		// Return the most basic response
+		_, err := w.Write([]byte(contents))
+		require.NoError(t, err)
+	})
+
+	// Make the test server
+	ts := httptest.NewServer(mux)
+
+	// Close the server at the end of the test
+	t.Cleanup(ts.Close)
+
+	return ts
+}
+
+func TestZenodoRemote(t *testing.T) {
+	recordID := "2600782"
+	doi := "10.5281/zenodo.2600782"
+
+	// The files in the dataset
+	files := map[string]string{
+		"README.md": "This is a dataset.",
+		"data.txt":  "Some data",
+	}
+
+	ts := prepareMockZenodoServer(t, files)
+	resolvedURL := ts.URL + "/record/" + recordID
+
+	doiResolverAPIURL := prepareMockDoiResolverServer(t, resolvedURL)
+
+	testConfig := configmap.Simple{
+		"type":                 "doi",
+		"doi":                  doi,
+		"provider":             "zenodo",
+		"doi_resolver_api_url": doiResolverAPIURL,
+	}
+	f, err := NewFs(context.Background(), remoteName, "", testConfig)
+	require.NoError(t, err)
+
+	// Test listing the DOI files
+	entries, err := f.List(context.Background(), "")
+	require.NoError(t, err)
+
+	sort.Sort(entries)
+
+	require.Equal(t, len(files), len(entries))
+
+	e := entries[0]
+	assert.Equal(t, "README.md", e.Remote())
+	assert.Equal(t, int64(18), e.Size())
+	_, ok := e.(*Object)
+	assert.True(t, ok)
+
+	e = entries[1]
+	assert.Equal(t, "data.txt", e.Remote())
+	assert.Equal(t, int64(9), e.Size())
+	_, ok = e.(*Object)
+	assert.True(t, ok)
+
+	// Test reading the DOI files
+	o, err := f.NewObject(context.Background(), "README.md")
+	require.NoError(t, err)
+	assert.Equal(t, int64(18), o.Size())
+	md5Hash, err := o.Hash(context.Background(), hash.MD5)
+	require.NoError(t, err)
+	assert.Equal(t, "464352b1cab5240e44528a56fda33d9d", md5Hash)
+	fd, err := o.Open(context.Background())
+	require.NoError(t, err)
+	data, err := io.ReadAll(fd)
+	require.NoError(t, err)
+	require.NoError(t, fd.Close())
+	assert.Equal(t, []byte(files["README.md"]), data)
+	do, ok := o.(fs.MimeTyper)
+	require.True(t, ok)
+	assert.Equal(t, "text/plain; charset=utf-8", do.MimeType(context.Background()))
+
+	o, err = f.NewObject(context.Background(), "data.txt")
+	require.NoError(t, err)
+	assert.Equal(t, int64(9), o.Size())
+	md5Hash, err = o.Hash(context.Background(), hash.MD5)
+	require.NoError(t, err)
+	assert.Equal(t, "5b82f8bf4df2bfb0e66ccaa7306fd024", md5Hash)
+	fd, err = o.Open(context.Background())
+	require.NoError(t, err)
+	data, err = io.ReadAll(fd)
+	require.NoError(t, err)
+	require.NoError(t, fd.Close())
+	assert.Equal(t, []byte(files["data.txt"]), data)
+	do, ok = o.(fs.MimeTyper)
+	require.True(t, ok)
+	assert.Equal(t, "text/plain; charset=utf-8", do.MimeType(context.Background()))
+}

backend/doi/doi_test.go

@@ -0,0 +1,16 @@
+// Test DOI filesystem interface
+package doi
+
+import (
+	"testing"
+
+	"github.com/rclone/rclone/fstest/fstests"
+)
+
+// TestIntegration runs integration tests against the remote
+func TestIntegration(t *testing.T) {
+	fstests.Run(t, &fstests.Opt{
+		RemoteName: "TestDoi:",
+		NilObject:  (*Object)(nil),
+	})
+}

backend/doi/invenio.go

@@ -0,0 +1,164 @@
+// Implementation for InvenioRDM
+
+package doi
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strings"
+	"time"
+
+	"github.com/rclone/rclone/backend/doi/api"
+	"github.com/rclone/rclone/fs"
+	"github.com/rclone/rclone/lib/rest"
+)
+
+var invenioRecordRegex = regexp.MustCompile(`\/records?\/(.+)`)
+
+// Returns true if resolvedURL is likely a DOI hosted on an InvenioRDM intallation
+func activateInvenio(ctx context.Context, srv *rest.Client, pacer *fs.Pacer, resolvedURL *url.URL) (isActive bool) {
+	_, _, err := resolveInvenioEndpoint(ctx, srv, pacer, resolvedURL)
+	return err == nil
+}
+
+// Resolve the main API endpoint for a DOI hosted on an InvenioRDM installation
+func resolveInvenioEndpoint(ctx context.Context, srv *rest.Client, pacer *fs.Pacer, resolvedURL *url.URL) (provider Provider, endpoint *url.URL, err error) {
+	var res *http.Response
+	opts := rest.Opts{
+		Method:  "GET",
+		RootURL: resolvedURL.String(),
+	}
+	err = pacer.Call(func() (bool, error) {
+		res, err = srv.Call(ctx, &opts)
+		return shouldRetry(ctx, res, err)
+	})
+	if err != nil {
+		return "", nil, err
+	}
+
+	// First, attempt to grab the API URL from the headers
+	var linksetURL *url.URL
+	links := parseLinkHeader(res.Header.Get("Link"))
+	for _, link := range links {
+		if link.Rel == "linkset" && link.Type == "application/linkset+json" {
+			parsed, err := url.Parse(link.Href)
+			if err == nil {
+				linksetURL = parsed
+				break
+			}
+		}
+	}
+
+	if linksetURL != nil {
+		endpoint, err = checkInvenioAPIURL(ctx, srv, pacer, linksetURL)
+		if err == nil {
+			return Invenio, endpoint, nil
+		}
+		fs.Logf(nil, "using linkset URL failed: %s", err.Error())
+	}
+
+	// If there is no linkset header, try to grab the record ID from the URL
+	recordID := ""
+	resURL := res.Request.URL
+	match := invenioRecordRegex.FindStringSubmatch(resURL.EscapedPath())
+	if match != nil {
+		recordID = match[1]
+		guessedURL := res.Request.URL.ResolveReference(&url.URL{
+			Path: "/api/records/" + recordID,
+		})
+		endpoint, err = checkInvenioAPIURL(ctx, srv, pacer, guessedURL)
+		if err == nil {
+			return Invenio, endpoint, nil
+		}
+		fs.Logf(nil, "guessing the URL failed: %s", err.Error())
+	}
+
+	return "", nil, fmt.Errorf("could not resolve the Invenio API endpoint for '%s'", resolvedURL.String())
+}
+
+func checkInvenioAPIURL(ctx context.Context, srv *rest.Client, pacer *fs.Pacer, resolvedURL *url.URL) (endpoint *url.URL, err error) {
+	var result api.InvenioRecordResponse
+	opts := rest.Opts{
+		Method:  "GET",
+		RootURL: resolvedURL.String(),
+	}
+	err = pacer.Call(func() (bool, error) {
+		res, err := srv.CallJSON(ctx, &opts, nil, &result)
+		return shouldRetry(ctx, res, err)
+	})
+	if err != nil {
+		return nil, err
+	}
+	if result.Links.Self == "" {
+		return nil, fmt.Errorf("could not parse API response from '%s'", resolvedURL.String())
+	}
+	return url.Parse(result.Links.Self)
+}
+
+// invenioProvider implements the doiProvider interface for InvenioRDM installations
+type invenioProvider struct {
+	f *Fs
+}
+
+// ListEntries returns the full list of entries found at the remote, regardless of root
+func (ip *invenioProvider) ListEntries(ctx context.Context) (entries []*Object, err error) {
+	// Use the cache if populated
+	cachedEntries, found := ip.f.cache.GetMaybe("files")
+	if found {
+		parsedEntries, ok := cachedEntries.([]Object)
+		if ok {
+			for _, entry := range parsedEntries {
+				newEntry := entry
+				entries = append(entries, &newEntry)
+			}
+			return entries, nil
+		}
+	}
+
+	filesURL := ip.f.endpoint.JoinPath("files")
+	var result api.InvenioFilesResponse
+	opts := rest.Opts{
+		Method: "GET",
+		Path:   strings.TrimLeft(filesURL.EscapedPath(), "/"),
+	}
+	err = ip.f.pacer.Call(func() (bool, error) {
+		res, err := ip.f.srv.CallJSON(ctx, &opts, nil, &result)
+		return shouldRetry(ctx, res, err)
+	})
+	if err != nil {
+		return nil, fmt.Errorf("readDir failed: %w", err)
+	}
+	for _, file := range result.Entries {
+		modTime, modTimeErr := time.Parse(time.RFC3339, file.Updated)
+		if modTimeErr != nil {
+			fs.Logf(ip.f, "error: could not parse last update time %v", modTimeErr)
+			modTime = timeUnset
+		}
+		entry := &Object{
+			fs:          ip.f,
+			remote:      file.Key,
+			contentURL:  file.Links.Content,
+			size:        file.Size,
+			modTime:     modTime,
+			contentType: file.MimeType,
+			md5:         strings.TrimPrefix(file.Checksum, "md5:"),
+		}
+		entries = append(entries, entry)
+	}
+	// Populate the cache
+	cacheEntries := []Object{}
+	for _, entry := range entries {
+		cacheEntries = append(cacheEntries, *entry)
+	}
+	ip.f.cache.Put("files", cacheEntries)
+	return entries, nil
+}
+
+func newInvenioProvider(f *Fs) doiProvider {
+	return &invenioProvider{
+		f: f,
+	}
+}

backend/doi/link_header.go

@@ -0,0 +1,75 @@
+package doi
+
+import (
+	"regexp"
+	"strings"
+)
+
+var linkRegex = regexp.MustCompile(`^<(.+)>$`)
+var valueRegex = regexp.MustCompile(`^"(.+)"$`)
+
+// headerLink represents a link as presented in HTTP headers
+// MDN Reference: https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/Link
+type headerLink struct {
+	Href   string
+	Rel    string
+	Type   string
+	Extras map[string]string
+}
+
+func parseLinkHeader(header string) (links []headerLink) {
+	for _, link := range strings.Split(header, ",") {
+		link = strings.TrimSpace(link)
+		parsed := parseLink(link)
+		if parsed != nil {
+			links = append(links, *parsed)
+		}
+	}
+	return links
+}
+
+func parseLink(link string) (parsedLink *headerLink) {
+	var parts []string
+	for _, part := range strings.Split(link, ";") {
+		parts = append(parts, strings.TrimSpace(part))
+	}
+
+	match := linkRegex.FindStringSubmatch(parts[0])
+	if match == nil {
+		return nil
+	}
+
+	result := &headerLink{
+		Href:   match[1],
+		Extras: map[string]string{},
+	}
+
+	for _, keyValue := range parts[1:] {
+		parsed := parseKeyValue(keyValue)
+		if parsed != nil {
+			key, value := parsed[0], parsed[1]
+			switch strings.ToLower(key) {
+			case "rel":
+				result.Rel = value
+			case "type":
+				result.Type = value
+			default:
+				result.Extras[key] = value
+			}
+		}
+	}
+	return result
+}
+
+func parseKeyValue(keyValue string) []string {
+	parts := strings.SplitN(keyValue, "=", 2)
+	if parts[0] == "" || len(parts) < 2 {
+		return nil
+	}
+	match := valueRegex.FindStringSubmatch(parts[1])
+	if match != nil {
+		parts[1] = match[1]
+		return parts
+	}
+	return parts
+}

backend/doi/link_header_internal_test.go

@@ -0,0 +1,44 @@
+package doi
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestParseLinkHeader(t *testing.T) {
+	header := "<https://zenodo.org/api/records/15063252> ; rel=\"linkset\" ; type=\"application/linkset+json\""
+	links := parseLinkHeader(header)
+	expected := headerLink{
+		Href:   "https://zenodo.org/api/records/15063252",
+		Rel:    "linkset",
+		Type:   "application/linkset+json",
+		Extras: map[string]string{},
+	}
+	assert.Contains(t, links, expected)
+
+	header = "<https://api.example.com/issues?page=2>; rel=\"prev\", <https://api.example.com/issues?page=4>; rel=\"next\", <https://api.example.com/issues?page=10>; rel=\"last\", <https://api.example.com/issues?page=1>; rel=\"first\""
+	links = parseLinkHeader(header)
+	expectedList := []headerLink{{
+		Href:   "https://api.example.com/issues?page=2",
+		Rel:    "prev",
+		Type:   "",
+		Extras: map[string]string{},
+	}, {
+		Href:   "https://api.example.com/issues?page=4",
+		Rel:    "next",
+		Type:   "",
+		Extras: map[string]string{},
+	}, {
+		Href:   "https://api.example.com/issues?page=10",
+		Rel:    "last",
+		Type:   "",
+		Extras: map[string]string{},
+	}, {
+		Href:   "https://api.example.com/issues?page=1",
+		Rel:    "first",
+		Type:   "",
+		Extras: map[string]string{},
+	}}
+	assert.Equal(t, links, expectedList)
+}

backend/doi/zenodo.go

@@ -0,0 +1,47 @@
+// Implementation for Zenodo
+
+package doi
+
+import (
+	"context"
+	"fmt"
+	"net/url"
+	"regexp"
+
+	"github.com/rclone/rclone/backend/doi/api"
+	"github.com/rclone/rclone/fs"
+	"github.com/rclone/rclone/lib/rest"
+)
+
+var zenodoRecordRegex = regexp.MustCompile(`zenodo[.](.+)`)
+
+// Resolve the main API endpoint for a DOI hosted on Zenodo
+func resolveZenodoEndpoint(ctx context.Context, srv *rest.Client, pacer *fs.Pacer, resolvedURL *url.URL, doi string) (provider Provider, endpoint *url.URL, err error) {
+	match := zenodoRecordRegex.FindStringSubmatch(doi)
+	if match == nil {
+		return "", nil, fmt.Errorf("could not derive API endpoint URL from '%s'", resolvedURL.String())
+	}
+
+	recordID := match[1]
+	endpointURL := resolvedURL.ResolveReference(&url.URL{Path: "/api/records/" + recordID})
+
+	var result api.InvenioRecordResponse
+	opts := rest.Opts{
+		Method:  "GET",
+		RootURL: endpointURL.String(),
+	}
+	err = pacer.Call(func() (bool, error) {
+		res, err := srv.CallJSON(ctx, &opts, nil, &result)
+		return shouldRetry(ctx, res, err)
+	})
+	if err != nil {
+		return "", nil, err
+	}
+
+	endpointURL, err = url.Parse(result.Links.Self)
+	if err != nil {
+		return "", nil, err
+	}
+
+	return Zenodo, endpointURL, nil
+}

docs/content/doi.md

@@ -0,0 +1,187 @@
+---
+title: "DOI"
+description: "Rclone docs for DOI"
+versionIntroduced: "?"
+---
+
+# {{< icon "fa fa-building-columns" >}} DOI
+
+The DOI remote is a read only remote for reading files from digital object identifiers (DOI).
+
+Currently, the DOI backend supports supports DOIs hosted with:
+- [InvenioRDM](https://inveniosoftware.org/products/rdm/)
+  - [Zenodo](https://zenodo.org)
+  - [CaltechDATA](https://data.caltech.edu)
+  - [Other InvenioRDM repositories](https://inveniosoftware.org/showcase/)
+- [Dataverse](https://dataverse.org)
+  - [Harvard Dataverse](https://dataverse.harvard.edu)
+  - [Other Dataverse repositories](https://dataverse.org/installations)
+
+Paths are specified as `remote:path`
+
+Paths may be as deep as required, e.g. `remote:directory/subdirectory`.
+
+## Configuration
+
+Here is an example of how to make a remote called `remote`.  First run:
+
+     rclone config
+
+This will guide you through an interactive setup process:
+
+```
+No remotes found, make a new one?
+n) New remote
+s) Set configuration password
+q) Quit config
+n/s/q> n
+Enter name for new remote.
+name> remote
+Type of storage to configure.
+Choose a number from below, or type in your own value
+[snip]
+XX / DOI datasets
+   \ (doi)
+[snip]
+Storage> doi
+Option doi.
+The DOI or the doi.org URL.
+Enter a value.
+doi> 10.5281/zenodo.5876941
+Edit advanced config?
+y) Yes
+n) No (default)
+y/n> n
+Configuration complete.
+Options:
+- type: doi
+- doi: 10.5281/zenodo.5876941
+Keep this "remote" remote?
+y) Yes this is OK (default)
+e) Edit this remote
+d) Delete this remote
+y/e/d> y
+```
+
+{{< rem autogenerated options start" - DO NOT EDIT - instead edit fs.RegInfo in backend/doi/doi.go then run make backenddocs" >}}
+### Standard options
+
+Here are the Standard options specific to doi (DOI datasets).
+
+#### --doi-doi
+
+The DOI or the doi.org URL.
+
+Properties:
+
+- Config:      doi
+- Env Var:     RCLONE_DOI_DOI
+- Type:        string
+- Required:    true
+
+### Advanced options
+
+Here are the Advanced options specific to doi (DOI datasets).
+
+#### --doi-provider
+
+DOI provider.
+
+The DOI provider can be set when rclone does not automatically recognize a supported DOI provider.
+
+Properties:
+
+- Config:      provider
+- Env Var:     RCLONE_DOI_PROVIDER
+- Type:        string
+- Required:    false
+- Examples:
+    - "auto"
+        - Auto-detect provider
+    - "zenodo"
+        - Zenodo
+    - "dataverse"
+        - Dataverse
+    - "invenio"
+        - Invenio
+
+#### --doi-doi-resolver-api-url
+
+The URL of the DOI resolver API to use.
+
+The DOI resolver can be set for testing or for cases when the the canonical DOI resolver API cannot be used.
+
+Defaults to "https://doi.org/api".
+
+Properties:
+
+- Config:      doi_resolver_api_url
+- Env Var:     RCLONE_DOI_DOI_RESOLVER_API_URL
+- Type:        string
+- Required:    false
+
+#### --doi-description
+
+Description of the remote.
+
+Properties:
+
+- Config:      description
+- Env Var:     RCLONE_DOI_DESCRIPTION
+- Type:        string
+- Required:    false
+
+## Backend commands
+
+Here are the commands specific to the doi backend.
+
+Run them with
+
+    rclone backend COMMAND remote:
+
+The help below will explain what arguments each command takes.
+
+See the [backend](/commands/rclone_backend/) command for more
+info on how to pass options and arguments.
+
+These can be run on a running backend using the rc command
+[backend/command](/rc/#backend-command).
+
+### metadata
+
+Show metadata about the DOI.
+
+    rclone backend metadata remote: [options] [<arguments>+]
+
+This command returns a JSON object with some information about the DOI.
+
+    rclone backend medatadata doi: 
+
+It returns a JSON object representing metadata about the DOI.
+
+
+### set
+
+Set command for updating the config parameters.
+
+    rclone backend set remote: [options] [<arguments>+]
+
+This set command can be used to update the config parameters
+for a running doi backend.
+
+Usage Examples:
+
+    rclone backend set doi: [-o opt_name=opt_value] [-o opt_name2=opt_value2]
+    rclone rc backend/command command=set fs=doi: [-o opt_name=opt_value] [-o opt_name2=opt_value2]
+    rclone rc backend/command command=set fs=doi: -o doi=NEW_DOI
+
+The option keys are named as they are in the config file.
+
+This rebuilds the connection to the doi backend when it is called with
+the new parameters. Only new parameters need be passed as the values
+will default to those currently in use.
+
+It doesn't return anything.
+
+
+{{< rem autogenerated options stop >}}