X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/6132d8efbc522b71d0084160abaaa87031678bdc..09559ebbb9f52c8b8a47e21d0a9c5720f3a2b7c6:/sdk/go/src/arvados.org/keepclient/keepclient.go?ds=inline

diff --git a/sdk/go/src/arvados.org/keepclient/keepclient.go b/sdk/go/src/arvados.org/keepclient/keepclient.go
index 6d75425331..93fcf4b3b9 100644
--- a/sdk/go/src/arvados.org/keepclient/keepclient.go
+++ b/sdk/go/src/arvados.org/keepclient/keepclient.go
@@ -1,20 +1,495 @@
 package keepclient
 
 import (
-	//"net/http"
+	"crypto/md5"
+	"crypto/tls"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+	"net/http"
 	"os"
+	"sort"
+	"strconv"
 )
 
 type KeepClient struct {
-	apiServer   string
-	apiToken    string
-	apiInsecure bool
+	ApiServer     string
+	ApiToken      string
+	ApiInsecure   bool
+	Service_roots []string
+	Want_replicas int
+	client        *http.Client
 }
 
-func InitKeepClient() *KeepClient {
-	kc := KeepClient{os.Getenv("ARVADOS_API_HOST"),
-		os.Getenv("ARVADOS_API_TOKEN"),
-		os.Getenv("ARVADOS_API_HOST_INSECURE") != ""}
+type KeepDisk struct {
+	Hostname string `json:"service_host"`
+	Port     int    `json:"service_port"`
+	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") != "")}
+
+	tr := &http.Transport{
+		TLSClientConfig: &tls.Config{InsecureSkipVerify: kc.ApiInsecure},
+	}
+
+	kc.client = &http.Client{Transport: tr}
+
+	err = kc.DiscoverKeepDisks()
+
+	return kc, err
+}
+
+func (this *KeepClient) DiscoverKeepDisks() error {
+	// Construct request of keep disk list
+	var req *http.Request
+	var err error
+	if req, err = http.NewRequest("GET", fmt.Sprintf("https://%s/arvados/v1/keep_disks", this.ApiServer), nil); err != nil {
+		return err
+	}
+
+	// Add api token header
+	req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
+
+	// 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
+	}
+
+	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"
+		}
+
+		// 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
+}
+
+func (this KeepClient) ShuffledServiceRoots(hash string) (pseq []string) {
+	// Build an ordering with which to query the Keep servers based on the
+	// contents of the hash.  "hash" is a hex-encoded number at least 8
+	// digits (32 bits) long
+
+	// seed used to calculate the next keep server from 'pool' to be added
+	// to 'pseq'
+	seed := hash
+
+	// Keep servers still to be added to the ordering
+	pool := make([]string, len(this.Service_roots))
+	copy(pool, this.Service_roots)
+
+	// output probe sequence
+	pseq = make([]string, 0, len(this.Service_roots))
+
+	// iterate while there are servers left to be assigned
+	for len(pool) > 0 {
+
+		if len(seed) < 8 {
+			// ran out of digits in the seed
+			if len(pseq) < (len(hash) / 4) {
+				// the number of servers added to the probe
+				// sequence is less than the number of 4-digit
+				// slices in 'hash' so refill the seed with the
+				// last 4 digits.
+				seed = hash[len(hash)-4:]
+			}
+			seed += hash
+		}
+
+		// Take the next 8 digits (32 bytes) and interpret as an integer,
+		// then modulus with the size of the remaining pool to get the next
+		// selected server.
+		probe, _ := strconv.ParseUint(seed[0:8], 16, 32)
+		probe %= uint64(len(pool))
+
+		// Append the selected server to the probe sequence and remove it
+		// from the pool.
+		pseq = append(pseq, pool[probe])
+		pool = append(pool[:probe], pool[probe+1:]...)
+
+		// Remove the digits just used from the seed
+		seed = seed[8:]
+	}
+	return pseq
+}
+
+type ReaderSlice struct {
+	slice        []byte
+	reader_error error
+}
+
+// Read repeatedly from the reader into the specified buffer, and report each
+// 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 {
+		log.Printf("ReadIntoBuffer doing read")
+		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 {
+			log.Printf("ReadIntoBuffer sending error %d %s", n, err.Error())
+			slices <- ReaderSlice{nil, err}
+			return
+		}
+
+		log.Printf("ReadIntoBuffer got %d", n)
+
+		if n > 0 {
+			log.Printf("ReadIntoBuffer sending readerslice")
+			// Make a slice with the contents of the read
+			slices <- ReaderSlice{ptr[:n], nil}
+			log.Printf("ReadIntoBuffer sent readerslice")
+
+			// Adjust the scratch space slice
+			ptr = ptr[n:]
+		}
+	}
+}
+
+// A read request to the Transfer() function
+type ReadRequest struct {
+	offset int
+	p      []byte
+	result chan<- ReadResult
+}
+
+// A read result from the Transfer() function
+type ReadResult struct {
+	n   int
+	err error
+}
+
+// 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, p, this.responses}
+	rr, valid := <-this.responses
+	if valid {
+		*this.offset += rr.n
+		return rr.n, rr.err
+	} else {
+		return 0, io.ErrUnexpectedEOF
+	}
+}
+
+// Close the responses channel
+func (this BufferReader) Close() error {
+	close(this.responses)
+	return nil
+}
+
+// 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 %t", req.offset, len(body), complete)
+	if req.offset < len(body) {
+		req.result <- ReadResult{copy(req.p, body[req.offset:]), nil}
+		return true
+	} else if complete && req.offset >= len(body) {
+		req.result <- ReadResult{0, io.EOF}
+		return true
+	} else {
+		return false
+	}
+}
+
+// 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 ReaderSlice = nil
+
+	// indicates whether the buffered data is complete
+	var complete bool = false
+
+	if source_reader != nil {
+		// 'body' is the buffer slice representing the body content read so far
+		body = source_buffer[:0]
+
+		// used to communicate slices of the buffer as they are
+		slices = make(chan ReaderSlice)
+
+		// Spin it off
+		go ReadIntoBuffer(source_buffer, source_reader, slices)
+	} else {
+		// use the whole buffer
+		body = source_buffer[:]
+
+		// buffer is complete
+		complete = true
+	}
+
+	pending_requests := make([]ReadRequest, 0)
+
+	for {
+		log.Printf("Doing select")
+		select {
+		case req, valid := <-requests:
+			log.Printf("Got read request")
+			// Handle a buffer read request
+			if valid {
+				if !HandleReadRequest(req, body, complete) {
+					log.Printf("Queued")
+					pending_requests = append(pending_requests, req)
+				}
+			} else {
+				// closed 'requests' channel indicates we're done
+				return
+			}
+
+		case bk, valid := <-slices:
+			// Got a new slice from the reader
+			if valid {
+				log.Printf("Got readerslice %d", len(bk.slice))
+
+				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
+					} else {
+						// some other reader error
+						return
+					}
+				}
+
+				if bk.slice != nil {
+					// adjust body bounds now that another slice has been read
+					body = source_buffer[0 : len(body)+len(bk.slice)]
+				}
+
+				// handle pending reads
+				n := 0
+				for n < len(pending_requests) {
+					if HandleReadRequest(pending_requests[n], body, complete) {
+						log.Printf("ReadRequest handled")
+
+						// 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 {
+						log.Printf("ReadRequest re-queued")
+
+						// Request wasn't handled, so keep it in the request slice
+						n += 1
+					}
+				}
+			} else {
+				if complete {
+					// no more reads
+					slices = nil
+				} else {
+					// reader channel closed without signaling EOF
+					reader_error <- io.ErrUnexpectedEOF
+					return
+				}
+			}
+		}
+	}
+}
+
+type UploadError struct {
+	err error
+	url string
+}
+
+func (this KeepClient) uploadToKeepServer(host string, hash string, body io.ReadCloser, upload_status chan<- UploadError) {
+	var req *http.Request
+	var err error
+	var url = fmt.Sprintf("%s/%s", host, hash)
+	if req, err = http.NewRequest("PUT", url, nil); err != nil {
+		upload_status <- UploadError{err, url}
+		return
+	}
+
+	req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
+	req.Body = body
+
+	var resp *http.Response
+	if resp, err = this.client.Do(req); err != nil {
+		upload_status <- UploadError{err, url}
+	}
+
+	if resp.StatusCode == http.StatusOK {
+		upload_status <- UploadError{io.EOF, url}
+	}
+}
+
+var KeepWriteError = errors.New("Could not write sufficient replicas")
+
+func (this KeepClient) putReplicas(
+	hash string,
+	requests chan ReadRequest,
+	reader_status chan error) error {
+
+	// Calculate the ordering for uploading to servers
+	sv := this.ShuffledServiceRoots(hash)
+
+	// The next server to try contacting
+	next_server := 0
+
+	// The number of active writers
+	active := 0
+
+	// Used to communicate status from the upload goroutines
+	upload_status := make(chan UploadError)
+	defer close(upload_status)
+
+	// Desired number of replicas
+	want_replicas := this.Want_replicas
+
+	for want_replicas > 0 {
+		for active < want_replicas {
+			// Start some upload requests
+			if next_server < len(sv) {
+				go this.uploadToKeepServer(sv[next_server], hash, MakeBufferReader(requests), upload_status)
+				next_server += 1
+				active += 1
+			} else {
+				return KeepWriteError
+			}
+		}
+
+		// Now wait for something to happen.
+		select {
+		case status := <-reader_status:
+			if status == io.EOF {
+				// good news!
+			} else {
+				// bad news
+				return status
+			}
+		case status := <-upload_status:
+			if status.err == io.EOF {
+				// good news!
+				want_replicas -= 1
+			} else {
+				// writing to keep server failed for some reason
+				log.Printf("Got error %s uploading to %s", status.err, status.url)
+			}
+			active -= 1
+		}
+	}
+
+	return nil
+}
+
+func (this KeepClient) PutHR(hash string, r io.Reader) error {
+
+	// Buffer for reads from 'r'
+	buffer := make([]byte, 64*1024*1024)
+
+	// Read requests on Transfer() buffer
+	requests := make(chan ReadRequest)
+	defer close(requests)
+
+	// Reporting reader error states
+	reader_status := make(chan error)
+
+	// Start the transfer goroutine
+	go Transfer(buffer, r, requests, reader_status)
+
+	return this.putReplicas(hash, requests, reader_status)
+}
+
+func (this KeepClient) PutHB(hash string, buffer []byte) 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)
+}
+
+func (this KeepClient) PutB(buffer []byte) error {
+	return this.PutHB(fmt.Sprintf("%x", md5.Sum(buffer)), buffer)
+}
 
-	return &kc
+func (this KeepClient) PutR(r io.Reader) error {
+	if buffer, err := ioutil.ReadAll(r); err != nil {
+		return err
+	} else {
+		return this.PutB(buffer)
+	}
 }