package keepclient
import (
+ "crypto/md5"
"crypto/tls"
"encoding/json"
+ "errors"
"fmt"
"io"
+ "io/ioutil"
+ "log"
"net/http"
"os"
"sort"
"strconv"
)
+// A Keep "block" is 64MB.
+const BLOCKSIZE = 64 * 1024 * 1024
+
+var BlockNotFound = errors.New("Block not found")
+var InsufficientReplicasError = errors.New("Could not write sufficient replicas")
+
type KeepClient struct {
ApiServer string
ApiToken string
ApiInsecure bool
Service_roots []string
+ Want_replicas int
+ Client *http.Client
}
type KeepDisk struct {
SSL bool `json:"service_ssl_flag"`
}
-func MakeKeepClient() (kc *KeepClient, err error) {
- kc = &KeepClient{
- ApiServer: os.Getenv("ARVADOS_API_HOST"),
- ApiToken: os.Getenv("ARVADOS_API_TOKEN"),
- ApiInsecure: (os.Getenv("ARVADOS_API_HOST_INSECURE") != "")}
-
- if err := kc.DiscoverKeepDisks(); err != nil {
- return nil, err
+func MakeKeepClient() (kc KeepClient, err error) {
+ tr := &http.Transport{
+ TLSClientConfig: &tls.Config{InsecureSkipVerify: kc.ApiInsecure},
}
- return kc, nil
-}
+ kc = KeepClient{
+ ApiServer: os.Getenv("ARVADOS_API_HOST"),
+ ApiToken: os.Getenv("ARVADOS_API_TOKEN"),
+ ApiInsecure: (os.Getenv("ARVADOS_API_HOST_INSECURE") != ""),
+ Want_replicas: 2,
+ Client: &http.Client{Transport: tr}}
-func (this *KeepClient) DiscoverKeepDisks() error {
- tr := &http.Transport{
- TLSClientConfig: &tls.Config{InsecureSkipVerify: this.ApiInsecure},
- }
- client := &http.Client{Transport: tr}
+ err = (&kc).DiscoverKeepServers()
+
+ return kc, err
+}
+func (this *KeepClient) DiscoverKeepServers() error {
+ // Construct request of keep disk list
var req *http.Request
var err error
- if req, err = http.NewRequest("GET", "https://localhost:3001/arvados/v1/keep_disks", nil); err != nil {
+ if req, err = http.NewRequest("GET", fmt.Sprintf("https://%s/arvados/v1/keep_disks", this.ApiServer), nil); err != nil {
return err
}
- var resp *http.Response
+ // Add api token header
req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
- if resp, err = client.Do(req); err != nil {
+
+ // Make the request
+ var resp *http.Response
+ if resp, err = this.Client.Do(req); err != nil {
return err
}
type SvcList struct {
Items []KeepDisk `json:"items"`
}
+
+ // Decode json reply
dec := json.NewDecoder(resp.Body)
var m SvcList
if err := dec.Decode(&m); err != nil {
return err
}
- this.Service_roots = make([]string, len(m.Items))
- for index, element := range m.Items {
+ listed := make(map[string]bool)
+ this.Service_roots = make([]string, 0, len(m.Items))
+
+ for _, element := range m.Items {
n := ""
if element.SSL {
n = "s"
}
- this.Service_roots[index] = fmt.Sprintf("http%s://%s:%d",
- n, element.Hostname, element.Port)
+
+ // Construct server URL
+ url := fmt.Sprintf("http%s://%s:%d", n, element.Hostname, element.Port)
+
+ // Skip duplicates
+ if !listed[url] {
+ listed[url] = true
+ this.Service_roots = append(this.Service_roots, url)
+ }
}
+
+ // Must be sorted for ShuffledServiceRoots() to produce consistent
+ // results.
sort.Strings(this.Service_roots)
+
return nil
}
reader_error error
}
-type Source <-chan ReaderSlice
-type Sink chan<- ReaderSlice
-type Status chan error
-
// Read repeatedly from the reader into the specified buffer, and report each
-// read to channel 'c'. Completes when Reader 'r' reports an error and closes
-// channel 'c'.
-func ReadIntoBuffer(buffer []byte, r io.Reader, c Sink) {
- defer close(c)
+// read to channel 'c'. Completes when Reader 'r' reports on the error channel
+// and closes channel 'c'.
+func ReadIntoBuffer(buffer []byte, r io.Reader, slices chan<- ReaderSlice) {
+ defer close(slices)
// Initially use entire buffer as scratch space
ptr := buffer[:]
- for len(ptr) > 0 {
- // Read into the scratch space
- n, err := r.Read(ptr)
+ for {
+ var n int
+ var err error
+ if len(ptr) > 0 {
+ // Read into the scratch space
+ n, err = r.Read(ptr)
+ } else {
+ // Ran out of scratch space, try reading one more byte
+ var b [1]byte
+ n, err = r.Read(b[:])
+
+ if n > 0 {
+ // Reader has more data but we have nowhere to
+ // put it, so we're stuffed
+ slices <- ReaderSlice{nil, io.ErrShortBuffer}
+ } else {
+ // Return some other error (hopefully EOF)
+ slices <- ReaderSlice{nil, err}
+ }
+ return
+ }
// End on error (includes EOF)
if err != nil {
- c <- ReaderSlice{nil, err}
+ slices <- ReaderSlice{nil, err}
return
}
- // Make a slice with the contents of the read
- c <- ReaderSlice{ptr[:n], nil}
+ if n > 0 {
+ // Make a slice with the contents of the read
+ slices <- ReaderSlice{ptr[:n], nil}
- // Adjust the scratch space slice
- ptr = ptr[n:]
- }
- if len(ptr) == 0 {
- c <- ReaderSlice{nil, io.ErrShortBuffer}
+ // Adjust the scratch space slice
+ ptr = ptr[n:]
+ }
}
}
-// Take slices from 'source' channel and write them to Writer 'w'. Reports read
-// or write errors on 'status'. Completes when 'source' channel is closed.
-/*func SinkWriter(source Source, w io.Writer, status Status) {
- can_write = true
+// A read request to the Transfer() function
+type ReadRequest struct {
+ offset int
+ maxsize int
+ result chan<- ReadResult
+}
+
+// A read result from the Transfer() function
+type ReadResult struct {
+ slice []byte
+ err error
+}
- for {
- // Get the next block from the source
- rs, valid := <-source
+// Reads from the buffer managed by the Transfer()
+type BufferReader struct {
+ offset *int
+ requests chan<- ReadRequest
+ responses chan ReadResult
+}
+func MakeBufferReader(requests chan<- ReadRequest) BufferReader {
+ return BufferReader{new(int), requests, make(chan ReadResult)}
+}
+
+// Reads from the buffer managed by the Transfer()
+func (this BufferReader) Read(p []byte) (n int, err error) {
+ this.requests <- ReadRequest{*this.offset, len(p), this.responses}
+ rr, valid := <-this.responses
+ if valid {
+ *this.offset += len(rr.slice)
+ return copy(p, rr.slice), rr.err
+ } else {
+ return 0, io.ErrUnexpectedEOF
+ }
+}
+
+func (this BufferReader) WriteTo(dest io.Writer) (written int64, err error) {
+ // Record starting offset in order to correctly report the number of bytes sent
+ starting_offset := *this.offset
+ for {
+ this.requests <- ReadRequest{*this.offset, 32 * 1024, this.responses}
+ rr, valid := <-this.responses
if valid {
- if rs.error != nil {
- // propagate reader status (should only be EOF)
- status <- rs.error
- } else if can_write {
- buf := rs.slice[:]
- for len(buf) > 0 {
- n, err := w.Write(buf)
- buf = buf[n:]
- if err == io.ErrShortWrite {
- // short write, so go around again
- } else if err != nil {
- // some other write error,
- // propagate error and stop
- // further writes
- status <- err
- can_write = false
- }
+ log.Printf("WriteTo slice %v %d %v", *this.offset, len(rr.slice), rr.err)
+ *this.offset += len(rr.slice)
+ if rr.err != nil {
+ if rr.err == io.EOF {
+ // EOF is not an error.
+ return int64(*this.offset - starting_offset), nil
+ } else {
+ return int64(*this.offset - starting_offset), rr.err
}
+ } else {
+ dest.Write(rr.slice)
}
} else {
- // source channel closed
- break
+ return int64(*this.offset), io.ErrUnexpectedEOF
}
}
-}*/
+}
+
+// Close the responses channel
+func (this BufferReader) Close() error {
+ close(this.responses)
+ return nil
+}
-func closeSinks(sinks_slice []Sink) {
- for _, s := range sinks_slice {
- close(s)
+// Handle a read request. Returns true if a response was sent, and false if
+// the request should be queued.
+func HandleReadRequest(req ReadRequest, body []byte, complete bool) bool {
+ log.Printf("HandleReadRequest %d %d %d", req.offset, req.maxsize, len(body))
+ if req.offset < len(body) {
+ var end int
+ if req.offset+req.maxsize < len(body) {
+ end = req.offset + req.maxsize
+ } else {
+ end = len(body)
+ }
+ req.result <- ReadResult{body[req.offset:end], nil}
+ return true
+ } else if complete && req.offset >= len(body) {
+ req.result <- ReadResult{nil, io.EOF}
+ return true
+ } else {
+ return false
}
}
-// Transfer data from a source (either an already-filled buffer, or a reader)
-// into one or more 'sinks'. If 'source' is valid, it will read from the
-// reader into the buffer and send the data to the sinks. Otherwise 'buffer'
-// it will just send the contents of the buffer to the sinks. Completes when
-// the 'sinks' channel is closed.
-func Transfer(source_buffer []byte, source_reader io.Reader, sinks <-chan Sink, reader_error chan error) {
+// If 'source_reader' is not nil, reads data from 'source_reader' and stores it
+// in the provided buffer. Otherwise, use the contents of 'buffer' as is.
+// Accepts read requests on the buffer on the 'requests' channel. Completes
+// when 'requests' channel is closed.
+func Transfer(source_buffer []byte, source_reader io.Reader, requests <-chan ReadRequest, reader_error chan error) {
// currently buffered data
var body []byte
// for receiving slices from ReadIntoBuffer
- var slices chan []byte = nil
+ var slices chan ReaderSlice = nil
// indicates whether the buffered data is complete
var complete bool = false
// 'body' is the buffer slice representing the body content read so far
body = source_buffer[:0]
- // used to communicate slices of the buffer as read
- reader_slices := make(chan []ReaderSlice)
+ // used to communicate slices of the buffer as they are
+ // ReadIntoBuffer will close 'slices' when it is done with it
+ slices = make(chan ReaderSlice)
// Spin it off
- go ReadIntoBuffer(source_buffer, source_reader, reader_slices)
+ go ReadIntoBuffer(source_buffer, source_reader, slices)
} else {
// use the whole buffer
body = source_buffer[:]
- // that's it
+ // buffer is complete
complete = true
}
- // list of sinks to send to
- sinks_slice := make([]Sink, 0)
- defer closeSinks(sinks_slice)
+ pending_requests := make([]ReadRequest, 0)
for {
select {
- case s, valid := <-sinks:
+ case req, valid := <-requests:
+ // Handle a buffer read request
if valid {
- // add to the sinks slice
- sinks_slice = append(sinks_slice, s)
-
- // catch up the sink with the current body contents
- if len(body) > 0 {
- s <- ReaderSlice{body, nil}
- if complete {
- s <- ReaderSlice{nil, io.EOF}
- }
+ if !HandleReadRequest(req, body, complete) {
+ pending_requests = append(pending_requests, req)
}
} else {
- // closed 'sinks' channel indicates we're done
+ // closed 'requests' channel indicates we're done
return
}
case bk, valid := <-slices:
+ // Got a new slice from the reader
if valid {
- if bk.err != nil {
- reader_error <- bk.err
- if bk.err == io.EOF {
+ if bk.reader_error != nil {
+ reader_error <- bk.reader_error
+ if bk.reader_error == io.EOF {
// EOF indicates the reader is done
// sending, so our buffer is complete.
complete = true
body = source_buffer[0 : len(body)+len(bk.slice)]
}
- // send the new slice to the sinks
- for _, s := range sinks_slice {
- s <- bk
- }
-
- if complete {
- // got an EOF, so close the sinks
- closeSinks(sinks_slice)
+ // handle pending reads
+ n := 0
+ for n < len(pending_requests) {
+ if HandleReadRequest(pending_requests[n], body, complete) {
+
+ // move the element from the
+ // back of the slice to
+ // position 'n', then shorten
+ // the slice by one element
+ pending_requests[n] = pending_requests[len(pending_requests)-1]
+ pending_requests = pending_requests[0 : len(pending_requests)-1]
+ } else {
- // truncate sinks slice
- sinks_slice = sinks_slice[:0]
+ // Request wasn't handled, so keep it in the request slice
+ n += 1
+ }
}
} else {
- // no more reads
- slices = nil
+ if complete {
+ // no more reads
+ slices = nil
+ } else {
+ // reader channel closed without signaling EOF
+ reader_error <- io.ErrUnexpectedEOF
+ return
+ }
}
}
}
}
-func (this KeepClient) ConnectToKeepServer(url string, sinks chan<- Sink, write_status chan<- error) {
- pipereader, pipewriter := io.Pipe()
+type UploadStatus struct {
+ Err error
+ Url string
+ StatusCode int
+}
+
+func (this KeepClient) uploadToKeepServer(host string, hash string, body io.ReadCloser,
+ upload_status chan<- UploadStatus, expectedLength int64) {
+
+ log.Printf("Uploading to %s", host)
var req *http.Request
- if req, err = http.NewRequest("POST", url, nil); err != nil {
- write_status <- err
+ var err error
+ var url = fmt.Sprintf("%s/%s", host, hash)
+ if req, err = http.NewRequest("PUT", url, nil); err != nil {
+ upload_status <- UploadStatus{err, url, 0}
+ return
}
- req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
- req.Body = pipereader
-
- // create channel to transfer slices from reader to writer
- tr := make(chan ReaderSlice)
- // start the writer goroutine
- go SinkWriter(tr, pipewriter, write_status)
+ if expectedLength > 0 {
+ req.ContentLength = expectedLength
+ }
- // now transfer the channel to the reader goroutine
- sinks <- tr
+ req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
+ req.Header.Add("Content-Type", "application/octet-stream")
+ req.Body = body
var resp *http.Response
+ if resp, err = this.Client.Do(req); err != nil {
+ upload_status <- UploadStatus{err, url, 0}
+ return
+ }
- if resp, err = client.Do(req); err != nil {
- return nil, err
+ if resp.StatusCode == http.StatusOK {
+ upload_status <- UploadStatus{nil, url, resp.StatusCode}
+ } else {
+ upload_status <- UploadStatus{errors.New(resp.Status), url, resp.StatusCode}
}
}
-var KeepWriteError = errors.new("Could not write sufficient replicas")
+func (this KeepClient) putReplicas(
+ hash string,
+ requests chan ReadRequest,
+ reader_status chan error,
+ expectedLength int64) (replicas int, err error) {
-func (this KeepClient) KeepPut(hash string, r io.Reader, want_replicas int) error {
- // Calculate the ordering to try writing to servers
+ // Calculate the ordering for uploading to servers
sv := this.ShuffledServiceRoots(hash)
// The next server to try contacting
- n := 0
+ next_server := 0
// The number of active writers
active := 0
- // Used to buffer reads from 'r'
- buffer := make([]byte, 64*1024*1024)
-
- // Used to send writers to the reader goroutine
- sinks := make(chan Sink)
- defer close(sinks)
-
- // Used to communicate status from the reader goroutine
- reader_status := make(chan error)
+ // Used to communicate status from the upload goroutines
+ upload_status := make(chan UploadStatus)
+ defer close(upload_status)
- // Start the reader goroutine
- go Transfer(buffer, r, sinks, reader_status)
+ // Desired number of replicas
+ remaining_replicas := this.Want_replicas
- // Used to communicate status from the writer goroutines
- write_status := make(chan error)
-
- for want_replicas > 0 {
- for active < want_replicas {
- // Start some writers
- if n < len(sv) {
- go this.ConnectToKeepServer(sv[n], sinks, write_status)
- n += 1
+ for remaining_replicas > 0 {
+ for active < remaining_replicas {
+ // Start some upload requests
+ if next_server < len(sv) {
+ go this.uploadToKeepServer(sv[next_server], hash, MakeBufferReader(requests), upload_status, expectedLength)
+ next_server += 1
active += 1
} else {
- return KeepWriteError
+ return (this.Want_replicas - remaining_replicas), InsufficientReplicasError
}
}
// good news!
} else {
// bad news
- return status
+ return (this.Want_replicas - remaining_replicas), status
}
- case status := <-write_status:
- if status == io.EOF {
+ case status := <-upload_status:
+ if status.StatusCode == 200 {
// good news!
- want_replicas -= 1
+ remaining_replicas -= 1
} else {
- // writing to keep server failed for some reason.
+ // writing to keep server failed for some reason
+ log.Printf("Keep server put to %v failed with '%v'",
+ status.Url, status.Err)
}
active -= 1
+ log.Printf("Upload status %v %v %v", status.StatusCode, remaining_replicas, active)
}
}
+
+ return (this.Want_replicas - remaining_replicas), nil
+}
+
+var OversizeBlockError = errors.New("Block too big")
+
+func (this KeepClient) PutHR(hash string, r io.Reader, expectedLength int64) (replicas int, err error) {
+
+ // Buffer for reads from 'r'
+ var buffer []byte
+ if expectedLength > 0 {
+ if expectedLength > BLOCKSIZE {
+ return 0, OversizeBlockError
+ }
+ buffer = make([]byte, expectedLength)
+ } else {
+ buffer = make([]byte, BLOCKSIZE)
+ }
+
+ // Read requests on Transfer() buffer
+ requests := make(chan ReadRequest)
+ defer close(requests)
+
+ // Reporting reader error states
+ reader_status := make(chan error)
+ defer close(reader_status)
+
+ // Start the transfer goroutine
+ go Transfer(buffer, r, requests, reader_status)
+
+ return this.putReplicas(hash, requests, reader_status, expectedLength)
+}
+
+func (this KeepClient) PutHB(hash string, buffer []byte) (replicas int, err error) {
+ // Read requests on Transfer() buffer
+ requests := make(chan ReadRequest)
+ defer close(requests)
+
+ // Start the transfer goroutine
+ go Transfer(buffer, nil, requests, nil)
+
+ return this.putReplicas(hash, requests, nil, int64(len(buffer)))
+}
+
+func (this KeepClient) PutB(buffer []byte) (hash string, replicas int, err error) {
+ hash = fmt.Sprintf("%x", md5.Sum(buffer))
+ replicas, err = this.PutHB(hash, buffer)
+ return hash, replicas, err
+}
+
+func (this KeepClient) PutR(r io.Reader) (hash string, replicas int, err error) {
+ if buffer, err := ioutil.ReadAll(r); err != nil {
+ return "", 0, err
+ } else {
+ return this.PutB(buffer)
+ }
+}
+
+func (this KeepClient) Get(hash string) (reader io.ReadCloser,
+ contentLength int64, url string, err error) {
+ return this.AuthorizedGet(hash, "", "")
+}
+
+func (this KeepClient) AuthorizedGet(hash string,
+ signature string,
+ timestamp string) (reader io.ReadCloser,
+ contentLength int64, url string, err error) {
+
+ // Calculate the ordering for asking servers
+ sv := this.ShuffledServiceRoots(hash)
+
+ for _, host := range sv {
+ var req *http.Request
+ var err error
+ var url string
+ if signature != "" {
+ url = fmt.Sprintf("%s/%s+A%s@%s", host, hash,
+ signature, timestamp)
+ } else {
+ url = fmt.Sprintf("%s/%s", host, hash)
+ }
+ if req, err = http.NewRequest("GET", url, nil); err != nil {
+ continue
+ }
+
+ req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
+
+ var resp *http.Response
+ if resp, err = this.Client.Do(req); err != nil {
+ continue
+ }
+
+ if resp.StatusCode == http.StatusOK {
+ return resp.Body, resp.ContentLength, url, nil
+ }
+ }
+
+ return nil, 0, "", BlockNotFound
+}
+
+func (this KeepClient) Ask(hash string) (contentLength int64, url string, err error) {
+ return this.AuthorizedAsk(hash, "", "")
+}
+
+func (this KeepClient) AuthorizedAsk(hash string, signature string,
+ timestamp string) (contentLength int64, url string, err error) {
+ // Calculate the ordering for asking servers
+ sv := this.ShuffledServiceRoots(hash)
+
+ for _, host := range sv {
+ var req *http.Request
+ var err error
+ if signature != "" {
+ url = fmt.Sprintf("%s/%s+A%s@%s", host, hash,
+ signature, timestamp)
+ } else {
+ url = fmt.Sprintf("%s/%s", host, hash)
+ }
+
+ if req, err = http.NewRequest("HEAD", url, nil); err != nil {
+ continue
+ }
+
+ req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
+
+ var resp *http.Response
+ if resp, err = this.Client.Do(req); err != nil {
+ continue
+ }
+
+ if resp.StatusCode == http.StatusOK {
+ return resp.ContentLength, url, nil
+ }
+ }
+
+ return 0, "", BlockNotFound
+
}