-// Copyright (C) The Arvados Authors. All rights reserved.
-//
-// SPDX-License-Identifier: AGPL-3.0
-
-package controller
-
-import (
- "bufio"
- "bytes"
- "context"
- "crypto/md5"
- "encoding/json"
- "fmt"
- "io"
- "io/ioutil"
- "net/http"
- "strings"
- "sync"
-
- "git.arvados.org/arvados.git/sdk/go/arvados"
- "git.arvados.org/arvados.git/sdk/go/httpserver"
- "git.arvados.org/arvados.git/sdk/go/keepclient"
-)
-
-func rewriteSignatures(clusterID string, expectHash string,
- resp *http.Response, requestError error) (newResponse *http.Response, err error) {
-
- if requestError != nil {
- return resp, requestError
- }
-
- if resp.StatusCode != http.StatusOK {
- return resp, nil
- }
-
- originalBody := resp.Body
- defer originalBody.Close()
-
- var col arvados.Collection
- err = json.NewDecoder(resp.Body).Decode(&col)
- if err != nil {
- return nil, err
- }
-
- // rewriting signatures will make manifest text 5-10% bigger so calculate
- // capacity accordingly
- updatedManifest := bytes.NewBuffer(make([]byte, 0, int(float64(len(col.ManifestText))*1.1)))
-
- hasher := md5.New()
- mw := io.MultiWriter(hasher, updatedManifest)
- sz := 0
-
- scanner := bufio.NewScanner(strings.NewReader(col.ManifestText))
- scanner.Buffer(make([]byte, 1048576), len(col.ManifestText))
- for scanner.Scan() {
- line := scanner.Text()
- tokens := strings.Split(line, " ")
- if len(tokens) < 3 {
- return nil, fmt.Errorf("Invalid stream (<3 tokens): %q", line)
- }
-
- n, err := mw.Write([]byte(tokens[0]))
- if err != nil {
- return nil, fmt.Errorf("Error updating manifest: %v", err)
- }
- sz += n
- for _, token := range tokens[1:] {
- n, err = mw.Write([]byte(" "))
- if err != nil {
- return nil, fmt.Errorf("Error updating manifest: %v", err)
- }
- sz += n
-
- m := keepclient.SignedLocatorRe.FindStringSubmatch(token)
- if m != nil {
- // Rewrite the block signature to be a remote signature
- _, err = fmt.Fprintf(updatedManifest, "%s%s%s+R%s-%s%s", m[1], m[2], m[3], clusterID, m[5][2:], m[8])
- if err != nil {
- return nil, fmt.Errorf("Error updating manifest: %v", err)
- }
-
- // for hash checking, ignore signatures
- n, err = fmt.Fprintf(hasher, "%s%s", m[1], m[2])
- if err != nil {
- return nil, fmt.Errorf("Error updating manifest: %v", err)
- }
- sz += n
- } else {
- n, err = mw.Write([]byte(token))
- if err != nil {
- return nil, fmt.Errorf("Error updating manifest: %v", err)
- }
- sz += n
- }
- }
- n, err = mw.Write([]byte("\n"))
- if err != nil {
- return nil, fmt.Errorf("Error updating manifest: %v", err)
- }
- sz += n
- }
-
- // Check that expected hash is consistent with
- // portable_data_hash field of the returned record
- if expectHash == "" {
- expectHash = col.PortableDataHash
- } else if expectHash != col.PortableDataHash {
- return nil, fmt.Errorf("portable_data_hash %q on returned record did not match expected hash %q ", expectHash, col.PortableDataHash)
- }
-
- // Certify that the computed hash of the manifest_text matches our expectation
- sum := hasher.Sum(nil)
- computedHash := fmt.Sprintf("%x+%v", sum, sz)
- if computedHash != expectHash {
- return nil, fmt.Errorf("Computed manifest_text hash %q did not match expected hash %q", computedHash, expectHash)
- }
-
- col.ManifestText = updatedManifest.String()
-
- newbody, err := json.Marshal(col)
- if err != nil {
- return nil, err
- }
-
- buf := bytes.NewBuffer(newbody)
- resp.Body = ioutil.NopCloser(buf)
- resp.ContentLength = int64(buf.Len())
- resp.Header.Set("Content-Length", fmt.Sprintf("%v", buf.Len()))
-
- return resp, nil
-}
-
-func filterLocalClusterResponse(resp *http.Response, requestError error) (newResponse *http.Response, err error) {
- if requestError != nil {
- return resp, requestError
- }
-
- if resp.StatusCode == http.StatusNotFound {
- // Suppress returning this result, because we want to
- // search the federation.
- return nil, nil
- }
- return resp, nil
-}
-
-type searchRemoteClusterForPDH struct {
- pdh string
- remoteID string
- mtx *sync.Mutex
- sentResponse *bool
- sharedContext *context.Context
- cancelFunc func()
- errors *[]string
- statusCode *int
-}
-
-func fetchRemoteCollectionByUUID(
- h *genericFederatedRequestHandler,
- effectiveMethod string,
- clusterID *string,
- uuid string,
- remainder string,
- w http.ResponseWriter,
- req *http.Request) bool {
-
- if effectiveMethod != "GET" {
- // Only handle GET requests right now
- return false
- }
-
- if uuid != "" {
- // Collection UUID GET request
- *clusterID = uuid[0:5]
- if *clusterID != "" && *clusterID != h.handler.Cluster.ClusterID {
- // request for remote collection by uuid
- resp, err := h.handler.remoteClusterRequest(*clusterID, req)
- newResponse, err := rewriteSignatures(*clusterID, "", resp, err)
- h.handler.proxy.ForwardResponse(w, newResponse, err)
- return true
- }
- }
-
- return false
-}
-
-func fetchRemoteCollectionByPDH(
- h *genericFederatedRequestHandler,
- effectiveMethod string,
- clusterID *string,
- uuid string,
- remainder string,
- w http.ResponseWriter,
- req *http.Request) bool {
-
- if effectiveMethod != "GET" {
- // Only handle GET requests right now
- return false
- }
-
- m := collectionsByPDHRe.FindStringSubmatch(req.URL.Path)
- if len(m) != 2 {
- return false
- }
-
- // Request for collection by PDH. Search the federation.
-
- // First, query the local cluster.
- resp, err := h.handler.localClusterRequest(req)
- newResp, err := filterLocalClusterResponse(resp, err)
- if newResp != nil || err != nil {
- h.handler.proxy.ForwardResponse(w, newResp, err)
- return true
- }
-
- // Create a goroutine for each cluster in the
- // RemoteClusters map. The first valid result gets
- // returned to the client. When that happens, all
- // other outstanding requests are cancelled
- sharedContext, cancelFunc := context.WithCancel(req.Context())
- defer cancelFunc()
-
- req = req.WithContext(sharedContext)
- wg := sync.WaitGroup{}
- pdh := m[1]
- success := make(chan *http.Response)
- errorChan := make(chan error, len(h.handler.Cluster.RemoteClusters))
-
- acquire, release := semaphore(h.handler.Cluster.API.MaxRequestAmplification)
-
- for remoteID := range h.handler.Cluster.RemoteClusters {
- if remoteID == h.handler.Cluster.ClusterID {
- // No need to query local cluster again
- continue
- }
- if remoteID == "*" {
- // This isn't a real remote cluster: it just sets defaults for unlisted remotes.
- continue
- }
-
- wg.Add(1)
- go func(remote string) {
- defer wg.Done()
- acquire()
- defer release()
- select {
- case <-sharedContext.Done():
- return
- default:
- }
-
- resp, err := h.handler.remoteClusterRequest(remote, req)
- wasSuccess := false
- defer func() {
- if resp != nil && !wasSuccess {
- resp.Body.Close()
- }
- }()
- if err != nil {
- errorChan <- err
- return
- }
- if resp.StatusCode != http.StatusOK {
- errorChan <- HTTPError{resp.Status, resp.StatusCode}
- return
- }
- select {
- case <-sharedContext.Done():
- return
- default:
- }
-
- newResponse, err := rewriteSignatures(remote, pdh, resp, nil)
- if err != nil {
- errorChan <- err
- return
- }
- select {
- case <-sharedContext.Done():
- case success <- newResponse:
- wasSuccess = true
- }
- }(remoteID)
- }
- go func() {
- wg.Wait()
- cancelFunc()
- }()
-
- errorCode := http.StatusNotFound
-
- for {
- select {
- case newResp = <-success:
- h.handler.proxy.ForwardResponse(w, newResp, nil)
- return true
- case <-sharedContext.Done():
- var errors []string
- for len(errorChan) > 0 {
- err := <-errorChan
- if httperr, ok := err.(HTTPError); !ok || httperr.Code != http.StatusNotFound {
- errorCode = http.StatusBadGateway
- }
- errors = append(errors, err.Error())
- }
- httpserver.Errors(w, errors, errorCode)
- return true
- }
- }
-
- // shouldn't ever get here
- return true
-}
projects / arvados.git / commitdiff