+// Copyright (C) The Arvados Authors. All rights reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+
/* Simple Arvados Go SDK for communicating with API server. */
package arvadosclient
import (
"bytes"
"crypto/tls"
+ "crypto/x509"
"encoding/json"
"errors"
"fmt"
"io"
+ "io/ioutil"
+ "log"
"net/http"
"net/url"
"os"
- "regexp"
"strings"
+ "sync"
+ "time"
+
+ "git.arvados.org/arvados.git/sdk/go/arvados"
)
-// Errors
+type StringMatcher func(string) bool
+
+var UUIDMatch StringMatcher = arvados.UUIDMatch
+var PDHMatch StringMatcher = arvados.PDHMatch
+
var MissingArvadosApiHost = errors.New("Missing required environment variable ARVADOS_API_HOST")
var MissingArvadosApiToken = errors.New("Missing required environment variable ARVADOS_API_TOKEN")
+var ErrInvalidArgument = errors.New("Invalid argument")
+
+// A common failure mode is to reuse a keepalive connection that has been
+// terminated (in a way that we can't detect) for being idle too long.
+// POST and DELETE are not safe to retry automatically, so we minimize
+// such failures by always using a new or recently active socket.
+var MaxIdleConnectionDuration = 30 * time.Second
-// Indicates an error that was returned by the API server.
+var RetryDelay = 2 * time.Second
+
+var (
+ defaultInsecureHTTPClient *http.Client
+ defaultSecureHTTPClient *http.Client
+ defaultHTTPClientMtx sync.Mutex
+)
+
+// APIServerError contains an error that was returned by the API server.
type APIServerError struct {
// Address of server returning error, of the form "host:port".
ServerAddress string
e.HttpStatusCode,
e.HttpStatusMessage,
e.ServerAddress)
- } else {
- return fmt.Sprintf("arvados API server error: %d: %s returned by %s",
- e.HttpStatusCode,
- e.HttpStatusMessage,
- e.ServerAddress)
}
+ return fmt.Sprintf("arvados API server error: %d: %s returned by %s",
+ e.HttpStatusCode,
+ e.HttpStatusMessage,
+ e.ServerAddress)
+}
+
+// StringBool tests whether s is suggestive of true. It returns true
+// if s is a mixed/uppoer/lower-case variant of "1", "yes", or "true".
+func StringBool(s string) bool {
+ s = strings.ToLower(s)
+ return s == "1" || s == "yes" || s == "true"
}
-// Helper type so we don't have to write out 'map[string]interface{}' every time.
+// Dict is a helper type so we don't have to write out 'map[string]interface{}' every time.
type Dict map[string]interface{}
-// Information about how to contact the Arvados server
+// ArvadosClient contains information about how to contact the Arvados server
type ArvadosClient struct {
+ // https
+ Scheme string
+
// Arvados API server, form "host:port"
ApiServer string
// the client is outside the cluster.
External bool
+ // Base URIs of Keep services, e.g., {"https://host1:8443",
+ // "https://host2:8443"}. If this is nil, Keep clients will
+ // use the arvados.v1.keep_services.accessible API to discover
+ // available services.
+ KeepServiceURIs []string
+
// Discovery document
DiscoveryDoc Dict
+
+ lastClosedIdlesAt time.Time
+
+ // Number of retries
+ Retries int
+
+ // X-Request-Id for outgoing requests
+ RequestID string
+}
+
+var CertFiles = []string{
+ "/etc/arvados/ca-certificates.crt",
+ "/etc/ssl/certs/ca-certificates.crt", // Debian/Ubuntu/Gentoo etc.
+ "/etc/pki/tls/certs/ca-bundle.crt", // Fedora/RHEL
}
-// Create a new ArvadosClient, initialized with standard Arvados environment
-// variables ARVADOS_API_HOST, ARVADOS_API_TOKEN, and (optionally)
-// ARVADOS_API_HOST_INSECURE.
-func MakeArvadosClient() (ac ArvadosClient, err error) {
- var matchTrue = regexp.MustCompile("^(?i:1|yes|true)$")
- insecure := matchTrue.MatchString(os.Getenv("ARVADOS_API_HOST_INSECURE"))
- external := matchTrue.MatchString(os.Getenv("ARVADOS_EXTERNAL_CLIENT"))
-
- ac = ArvadosClient{
- ApiServer: os.Getenv("ARVADOS_API_HOST"),
- ApiToken: os.Getenv("ARVADOS_API_TOKEN"),
- ApiInsecure: insecure,
- Client: &http.Client{Transport: &http.Transport{
- TLSClientConfig: &tls.Config{InsecureSkipVerify: insecure}}},
- External: external}
-
- if ac.ApiServer == "" {
- return ac, MissingArvadosApiHost
+// MakeTLSConfig sets up TLS configuration for communicating with
+// Arvados and Keep services.
+func MakeTLSConfig(insecure bool) *tls.Config {
+ tlsconfig := tls.Config{InsecureSkipVerify: insecure}
+
+ if !insecure {
+ // Use the first entry in CertFiles that we can read
+ // certificates from. If none of those work out, use
+ // the Go defaults.
+ certs := x509.NewCertPool()
+ for _, file := range CertFiles {
+ data, err := ioutil.ReadFile(file)
+ if err != nil {
+ if !os.IsNotExist(err) {
+ log.Printf("proceeding without loading cert file %q: %s", file, err)
+ }
+ continue
+ }
+ if !certs.AppendCertsFromPEM(data) {
+ log.Printf("unable to load any certificates from %v", file)
+ continue
+ }
+ tlsconfig.RootCAs = certs
+ break
+ }
}
- if ac.ApiToken == "" {
- return ac, MissingArvadosApiToken
+
+ return &tlsconfig
+}
+
+// New returns an ArvadosClient using the given arvados.Client
+// configuration. This is useful for callers who load arvados.Client
+// fields from configuration files but still need to use the
+// arvadosclient.ArvadosClient package.
+func New(c *arvados.Client) (*ArvadosClient, error) {
+ ac := &ArvadosClient{
+ Scheme: "https",
+ ApiServer: c.APIHost,
+ ApiToken: c.AuthToken,
+ ApiInsecure: c.Insecure,
+ Client: &http.Client{
+ Timeout: 5 * time.Minute,
+ Transport: &http.Transport{
+ TLSClientConfig: MakeTLSConfig(c.Insecure)},
+ },
+ External: false,
+ Retries: 2,
+ KeepServiceURIs: c.KeepServiceURIs,
+ lastClosedIdlesAt: time.Now(),
}
- return ac, err
+ return ac, nil
}
-// Low-level access to a resource.
-//
-// method - HTTP method, one of GET, HEAD, PUT, POST or DELETE
-// resource - the arvados resource to act on
-// uuid - the uuid of the specific item to access (may be empty)
-// action - sub-action to take on the resource or uuid (may be empty)
-// parameters - method parameters
-//
-// return
-// reader - the body reader, or nil if there was an error
-// err - error accessing the resource, or nil if no error
-func (this ArvadosClient) CallRaw(method string, resource string, uuid string, action string, parameters Dict) (reader io.ReadCloser, err error) {
- var req *http.Request
+// MakeArvadosClient creates a new ArvadosClient using the standard
+// environment variables ARVADOS_API_HOST, ARVADOS_API_TOKEN,
+// ARVADOS_API_HOST_INSECURE, ARVADOS_EXTERNAL_CLIENT, and
+// ARVADOS_KEEP_SERVICES.
+func MakeArvadosClient() (ac *ArvadosClient, err error) {
+ ac, err = New(arvados.NewClientFromEnv())
+ if err != nil {
+ return
+ }
+ ac.External = StringBool(os.Getenv("ARVADOS_EXTERNAL_CLIENT"))
+ return
+}
+// CallRaw is the same as Call() but returns a Reader that reads the
+// response body, instead of taking an output object.
+func (c *ArvadosClient) CallRaw(method string, resourceType string, uuid string, action string, parameters Dict) (reader io.ReadCloser, err error) {
+ scheme := c.Scheme
+ if scheme == "" {
+ scheme = "https"
+ }
+ if c.ApiServer == "" {
+ return nil, fmt.Errorf("Arvados client is not configured (target API host is not set). Maybe env var ARVADOS_API_HOST should be set first?")
+ }
u := url.URL{
- Scheme: "https",
- Host: this.ApiServer}
+ Scheme: scheme,
+ Host: c.ApiServer}
- if resource != API_DISCOVERY_RESOURCE {
+ if resourceType != ApiDiscoveryResource {
u.Path = "/arvados/v1"
}
- if resource != "" {
- u.Path = u.Path + "/" + resource
+ if resourceType != "" {
+ u.Path = u.Path + "/" + resourceType
}
if uuid != "" {
u.Path = u.Path + "/" + uuid
parameters = make(Dict)
}
- parameters["format"] = "json"
-
vals := make(url.Values)
for k, v := range parameters {
- m, err := json.Marshal(v)
- if err == nil {
+ if s, ok := v.(string); ok {
+ vals.Set(k, s)
+ } else if m, err := json.Marshal(v); err == nil {
vals.Set(k, string(m))
}
}
- if method == "GET" || method == "HEAD" {
- u.RawQuery = vals.Encode()
- if req, err = http.NewRequest(method, u.String(), nil); err != nil {
- return nil, err
- }
- } else {
- if req, err = http.NewRequest(method, u.String(), bytes.NewBufferString(vals.Encode())); err != nil {
- return nil, err
- }
- req.Header.Add("Content-Type", "application/x-www-form-urlencoded")
+ retryable := false
+ switch method {
+ case "GET", "HEAD", "PUT", "OPTIONS", "DELETE":
+ retryable = true
}
- // Add api token header
- req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
- if this.External {
- req.Header.Add("X-External-Client", "1")
+ // Non-retryable methods such as POST are not safe to retry automatically,
+ // so we minimize such failures by always using a new or recently active socket
+ if !retryable {
+ if time.Since(c.lastClosedIdlesAt) > MaxIdleConnectionDuration {
+ c.lastClosedIdlesAt = time.Now()
+ c.Client.Transport.(*http.Transport).CloseIdleConnections()
+ }
}
// Make the request
+ var req *http.Request
var resp *http.Response
- if resp, err = this.Client.Do(req); err != nil {
- return nil, err
- }
- if resp.StatusCode == http.StatusOK {
- return resp.Body, nil
+ for attempt := 0; attempt <= c.Retries; attempt++ {
+ if method == "GET" || method == "HEAD" {
+ u.RawQuery = vals.Encode()
+ if req, err = http.NewRequest(method, u.String(), nil); err != nil {
+ return nil, err
+ }
+ } else {
+ if req, err = http.NewRequest(method, u.String(), bytes.NewBufferString(vals.Encode())); err != nil {
+ return nil, err
+ }
+ req.Header.Add("Content-Type", "application/x-www-form-urlencoded")
+ }
+
+ // Add api token header
+ req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", c.ApiToken))
+ if c.RequestID != "" {
+ req.Header.Add("X-Request-Id", c.RequestID)
+ }
+ if c.External {
+ req.Header.Add("X-External-Client", "1")
+ }
+
+ resp, err = c.Client.Do(req)
+ if err != nil {
+ if retryable {
+ time.Sleep(RetryDelay)
+ continue
+ } else {
+ return nil, err
+ }
+ }
+
+ if resp.StatusCode == http.StatusOK {
+ return resp.Body, nil
+ }
+
+ defer resp.Body.Close()
+
+ switch resp.StatusCode {
+ case 408, 409, 422, 423, 500, 502, 503, 504:
+ time.Sleep(RetryDelay)
+ continue
+ default:
+ return nil, newAPIServerError(c.ApiServer, resp)
+ }
}
- defer resp.Body.Close()
- return nil, newAPIServerError(this.ApiServer, resp)
+ if resp != nil {
+ return nil, newAPIServerError(c.ApiServer, resp)
+ }
+ return nil, err
}
func newAPIServerError(ServerAddress string, resp *http.Response) APIServerError {
return ase
}
-// Access to a resource.
+// Call an API endpoint and parse the JSON response into an object.
//
-// method - HTTP method, one of GET, HEAD, PUT, POST or DELETE
-// resource - the arvados resource to act on
-// uuid - the uuid of the specific item to access (may be empty)
-// action - sub-action to take on the resource or uuid (may be empty)
-// parameters - method parameters
-// output - a map or annotated struct which is a legal target for encoding/json/Decoder
-// return
-// err - error accessing the resource, or nil if no error
-func (this ArvadosClient) Call(method string, resource string, uuid string, action string, parameters Dict, output interface{}) (err error) {
- var reader io.ReadCloser
- reader, err = this.CallRaw(method, resource, uuid, action, parameters)
+// method - HTTP method: GET, HEAD, PUT, POST, PATCH or DELETE.
+// resourceType - the type of arvados resource to act on (e.g., "collections", "pipeline_instances").
+// uuid - the uuid of the specific item to access. May be empty.
+// action - API method name (e.g., "lock"). This is often empty if implied by method and uuid.
+// parameters - method parameters.
+// output - a map or annotated struct which is a legal target for encoding/json/Decoder.
+//
+// Returns a non-nil error if an error occurs making the API call, the
+// API responds with a non-successful HTTP status, or an error occurs
+// parsing the response body.
+func (c *ArvadosClient) Call(method, resourceType, uuid, action string, parameters Dict, output interface{}) error {
+ reader, err := c.CallRaw(method, resourceType, uuid, action, parameters)
if reader != nil {
defer reader.Close()
}
return nil
}
-// Create a new instance of a resource.
-//
-// resource - the arvados resource on which to create an item
-// parameters - method parameters
-// output - a map or annotated struct which is a legal target for encoding/json/Decoder
-// return
-// err - error accessing the resource, or nil if no error
-func (this ArvadosClient) Create(resource string, parameters Dict, output interface{}) (err error) {
- return this.Call("POST", resource, "", "", parameters, output)
+// Create a new resource. See Call for argument descriptions.
+func (c *ArvadosClient) Create(resourceType string, parameters Dict, output interface{}) error {
+ return c.Call("POST", resourceType, "", "", parameters, output)
}
-// Delete an instance of a resource.
-//
-// resource - the arvados resource on which to delete an item
-// uuid - the item to delete
-// parameters - method parameters
-// output - a map or annotated struct which is a legal target for encoding/json/Decoder
-// return
-// err - error accessing the resource, or nil if no error
-func (this ArvadosClient) Delete(resource string, uuid string, parameters Dict, output interface{}) (err error) {
- return this.Call("DELETE", resource, uuid, "", parameters, output)
+// Delete a resource. See Call for argument descriptions.
+func (c *ArvadosClient) Delete(resource string, uuid string, parameters Dict, output interface{}) (err error) {
+ return c.Call("DELETE", resource, uuid, "", parameters, output)
}
-// Update fields of an instance of a resource.
-//
-// resource - the arvados resource on which to update the item
-// uuid - the item to update
-// parameters - method parameters
-// output - a map or annotated struct which is a legal target for encoding/json/Decoder
-// return
-// err - error accessing the resource, or nil if no error
-func (this ArvadosClient) Update(resource string, uuid string, parameters Dict, output interface{}) (err error) {
- return this.Call("PUT", resource, uuid, "", parameters, output)
+// Update attributes of a resource. See Call for argument descriptions.
+func (c *ArvadosClient) Update(resourceType string, uuid string, parameters Dict, output interface{}) (err error) {
+ return c.Call("PUT", resourceType, uuid, "", parameters, output)
}
-// List the instances of a resource
-//
-// resource - the arvados resource on which to list
-// parameters - method parameters
-// output - a map or annotated struct which is a legal target for encoding/json/Decoder
-// return
-// err - error accessing the resource, or nil if no error
-func (this ArvadosClient) List(resource string, parameters Dict, output interface{}) (err error) {
- return this.Call("GET", resource, "", "", parameters, output)
+// Get a resource. See Call for argument descriptions.
+func (c *ArvadosClient) Get(resourceType string, uuid string, parameters Dict, output interface{}) (err error) {
+ if !UUIDMatch(uuid) && !(resourceType == "collections" && PDHMatch(uuid)) {
+ // No object has uuid == "": there is no need to make
+ // an API call. Furthermore, the HTTP request for such
+ // an API call would be "GET /arvados/v1/type/", which
+ // is liable to be misinterpreted as the List API.
+ return ErrInvalidArgument
+ }
+ return c.Call("GET", resourceType, uuid, "", parameters, output)
}
-// API Discovery
-//
-// parameter - name of parameter to be discovered
-// return
-// value - value of the discovered parameter
-// err - error accessing the resource, or nil if no error
-var API_DISCOVERY_RESOURCE string = "discovery/v1/apis/arvados/v1/rest"
-
-func (this *ArvadosClient) Discovery(parameter string) (value interface{}, err error) {
- if len(this.DiscoveryDoc) == 0 {
- this.DiscoveryDoc = make(Dict)
- err = this.Call("GET", API_DISCOVERY_RESOURCE, "", "", nil, &this.DiscoveryDoc)
+// List resources of a given type. See Call for argument descriptions.
+func (c *ArvadosClient) List(resource string, parameters Dict, output interface{}) (err error) {
+ return c.Call("GET", resource, "", "", parameters, output)
+}
+
+const ApiDiscoveryResource = "discovery/v1/apis/arvados/v1/rest"
+
+// Discovery returns the value of the given parameter in the discovery
+// document. Returns a non-nil error if the discovery document cannot
+// be retrieved/decoded. Returns ErrInvalidArgument if the requested
+// parameter is not found in the discovery document.
+func (c *ArvadosClient) Discovery(parameter string) (value interface{}, err error) {
+ if len(c.DiscoveryDoc) == 0 {
+ c.DiscoveryDoc = make(Dict)
+ err = c.Call("GET", ApiDiscoveryResource, "", "", nil, &c.DiscoveryDoc)
if err != nil {
return nil, err
}
}
var found bool
- value, found = this.DiscoveryDoc[parameter]
+ value, found = c.DiscoveryDoc[parameter]
if found {
return value, nil
- } else {
- return value, errors.New("Not found")
}
+ return value, ErrInvalidArgument
+}
+
+// ClusterConfig returns the value of the given key in the current cluster's
+// exported config. If key is an empty string, it'll return the entire config.
+func (c *ArvadosClient) ClusterConfig(key string) (config interface{}, err error) {
+ var clusterConfig interface{}
+ err = c.Call("GET", "config", "", "", nil, &clusterConfig)
+ if err != nil {
+ return nil, err
+ }
+ if key == "" {
+ return clusterConfig, nil
+ }
+ configData, ok := clusterConfig.(map[string]interface{})[key]
+ if !ok {
+ return nil, ErrInvalidArgument
+ }
+ return configData, nil
+}
+
+func (c *ArvadosClient) httpClient() *http.Client {
+ if c.Client != nil {
+ return c.Client
+ }
+ cl := &defaultSecureHTTPClient
+ if c.ApiInsecure {
+ cl = &defaultInsecureHTTPClient
+ }
+ if *cl == nil {
+ defaultHTTPClientMtx.Lock()
+ defer defaultHTTPClientMtx.Unlock()
+ *cl = &http.Client{Transport: &http.Transport{
+ TLSClientConfig: MakeTLSConfig(c.ApiInsecure)}}
+ }
+ return *cl
}