"strings"
)
-// Errors
+type StringMatcher func(string) bool
+
+var UUIDMatch StringMatcher = regexp.MustCompile(`^[a-z0-9]{5}-[a-z0-9]{5}-[a-z0-9]{15}$`).MatchString
+var PDHMatch StringMatcher = regexp.MustCompile(`^[0-9a-f]{32}\+\d+$`).MatchString
+
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")
+
+// Indicates an error that was returned by the API server.
+type APIServerError struct {
+ // Address of server returning error, of the form "host:port".
+ ServerAddress string
+
+ // Components of server response.
+ HttpStatusCode int
+ HttpStatusMessage string
-type ArvadosApiError struct {
- error
- HttpStatusCode int
- HttpStatus string
+ // Additional error details from response body.
+ ErrorDetails []string
}
-func (e ArvadosApiError) Error() string { return e.error.Error() }
+func (e APIServerError) Error() string {
+ if len(e.ErrorDetails) > 0 {
+ return fmt.Sprintf("arvados API server error: %s (%d: %s) returned by %s",
+ strings.Join(e.ErrorDetails, "; "),
+ 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)
+ }
+}
// 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
type ArvadosClient struct {
+ // https
+ Scheme string
+
// Arvados API server, form "host:port"
ApiServer string
// If true, sets the X-External-Client header to indicate
// the client is outside the cluster.
External bool
+
+ // Discovery document
+ DiscoveryDoc Dict
+
+ // Number of retries
+ Retries int
}
-// Create a new KeepClient, initialized with standard Arvados environment
+// Create a new ArvadosClient, initialized with standard Arvados environment
// variables ARVADOS_API_HOST, ARVADOS_API_TOKEN, and (optionally)
// ARVADOS_API_HOST_INSECURE.
-func MakeArvadosClient() (kc ArvadosClient, err error) {
+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"))
- kc = ArvadosClient{
+ ac = ArvadosClient{
+ Scheme: "https",
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}
+ External: external,
+ Retries: 2}
- if kc.ApiServer == "" {
- return kc, MissingArvadosApiHost
+ if ac.ApiServer == "" {
+ return ac, MissingArvadosApiHost
}
- if kc.ApiToken == "" {
- return kc, MissingArvadosApiToken
+ if ac.ApiToken == "" {
+ return ac, MissingArvadosApiToken
}
- return kc, err
+ return ac, err
}
-// 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
-
+// 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"
+ }
u := url.URL{
- Scheme: "https",
- Host: this.ApiServer}
+ Scheme: scheme,
+ Host: c.ApiServer}
- u.Path = "/arvados/v1"
+ if resourceType != API_DISCOVERY_RESOURCE {
+ 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
+ // Make the request
+ remainingTries := 1 + c.Retries
+ var req *http.Request
+ var resp *http.Response
+ var errs []string
+ var badResp bool
+
+ for remainingTries > 0 {
+ 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")
}
- } else {
- if req, err = http.NewRequest(method, u.String(), bytes.NewBufferString(vals.Encode())); err != nil {
- return nil, err
+
+ // Add api token header
+ req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", c.ApiToken))
+ if c.External {
+ req.Header.Add("X-External-Client", "1")
}
- req.Header.Add("Content-Type", "application/x-www-form-urlencoded")
- }
- // Add api token header
- req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.ApiToken))
- if this.External {
- req.Header.Add("X-External-Client", "1")
- }
+ resp, err = c.Client.Do(req)
+ if err != nil {
+ if method == "GET" || method == "HEAD" || method == "PUT" {
+ errs = append(errs, err.Error())
+ badResp = false
+ remainingTries -= 1
+ continue
+ } else {
+ return nil, err
+ }
+ }
- // Make the 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
+ }
+
+ defer resp.Body.Close()
+
+ if resp.StatusCode == 408 ||
+ resp.StatusCode == 409 ||
+ resp.StatusCode == 422 ||
+ resp.StatusCode == 423 ||
+ resp.StatusCode == 500 ||
+ resp.StatusCode == 502 ||
+ resp.StatusCode == 503 ||
+ resp.StatusCode == 504 {
+ badResp = true
+ remainingTries -= 1
+ continue
+ } else {
+ return nil, newAPIServerError(c.ApiServer, resp)
+ }
}
- if resp.StatusCode == http.StatusOK {
- return resp.Body, nil
+ if badResp {
+ return nil, newAPIServerError(c.ApiServer, resp)
+ } else {
+ return nil, fmt.Errorf("%v", errs)
}
+}
+
+func newAPIServerError(ServerAddress string, resp *http.Response) APIServerError {
- defer resp.Body.Close()
- errorText := fmt.Sprintf("API response: %s", resp.Status)
+ ase := APIServerError{
+ ServerAddress: ServerAddress,
+ HttpStatusCode: resp.StatusCode,
+ HttpStatusMessage: resp.Status}
// If the response body has {"errors":["reason1","reason2"]}
// then return those reasons.
var errInfo = Dict{}
if err := json.NewDecoder(resp.Body).Decode(&errInfo); err == nil {
if errorList, ok := errInfo["errors"]; ok {
- var errorStrings []string
if errArray, ok := errorList.([]interface{}); ok {
for _, errItem := range errArray {
// We expect an array of strings here.
// Non-strings will be passed along
// JSON-encoded.
if s, ok := errItem.(string); ok {
- errorStrings = append(errorStrings, s)
+ ase.ErrorDetails = append(ase.ErrorDetails, s)
} else if j, err := json.Marshal(errItem); err == nil {
- errorStrings = append(errorStrings, string(j))
+ ase.ErrorDetails = append(ase.ErrorDetails, string(j))
}
}
- errorText = strings.Join(errorStrings, "; ")
}
}
}
- return nil, ArvadosApiError{errors.New(errorText), resp.StatusCode, resp.Status}
+ 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 string, resourceType string, uuid string, 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)
+// Modify 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)
+}
+
+// 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 API_DISCOVERY_RESOURCE = "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", API_DISCOVERY_RESOURCE, "", "", nil, &c.DiscoveryDoc)
+ if err != nil {
+ return nil, err
+ }
+ }
+
+ var found bool
+ value, found = c.DiscoveryDoc[parameter]
+ if found {
+ return value, nil
+ } else {
+ return value, ErrInvalidArgument
+ }
}
projects / arvados.git / blobdiff