X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/f95ac4c11b99daea342be0fba98e66c92d70e54c..f827088cc812a217bfb46aca66be62b79b7ed973:/sdk/go/arvados/client.go

diff --git a/sdk/go/arvados/client.go b/sdk/go/arvados/client.go
index 562c8c1e7d..13bb3bf80d 100644
--- a/sdk/go/arvados/client.go
+++ b/sdk/go/arvados/client.go
@@ -9,6 +9,7 @@ import (
 	"context"
 	"crypto/tls"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -67,16 +68,20 @@ type Client struct {
 	dd *DiscoveryDocument
 
 	defaultRequestID string
+
+	// APIHost and AuthToken were loaded from ARVADOS_* env vars
+	// (used to customize "no host/token" error messages)
+	loadedFromEnv bool
 }
 
-// The default http.Client used by a Client with Insecure==true and
-// Client==nil.
+// InsecureHTTPClient is the default http.Client used by a Client with
+// Insecure==true and Client==nil.
 var InsecureHTTPClient = &http.Client{
 	Transport: &http.Transport{
 		TLSClientConfig: &tls.Config{
 			InsecureSkipVerify: true}}}
 
-// The default http.Client used by a Client otherwise.
+// DefaultSecureClient is the default http.Client used by a Client otherwise.
 var DefaultSecureClient = &http.Client{}
 
 // NewClientFromConfig creates a new Client that uses the endpoints in
@@ -123,6 +128,7 @@ func NewClientFromEnv() *Client {
 		Insecure:        insecure,
 		KeepServiceURIs: svcs,
 		Timeout:         5 * time.Minute,
+		loadedFromEnv:   true,
 	}
 }
 
@@ -306,11 +312,18 @@ func (c *Client) RequestAndDecode(dst interface{}, method, path string, body io.
 	return c.RequestAndDecodeContext(context.Background(), dst, method, path, body, params)
 }
 
+// RequestAndDecodeContext does the same as RequestAndDecode, but with a context
 func (c *Client) RequestAndDecodeContext(ctx context.Context, dst interface{}, method, path string, body io.Reader, params interface{}) error {
 	if body, ok := body.(io.Closer); ok {
 		// Ensure body is closed even if we error out early
 		defer body.Close()
 	}
+	if c.APIHost == "" {
+		if c.loadedFromEnv {
+			return errors.New("ARVADOS_API_HOST and/or ARVADOS_API_TOKEN environment variables are not set")
+		}
+		return errors.New("arvados.Client cannot perform request: APIHost is not set")
+	}
 	urlString := c.apiURL(path)
 	urlValues, err := anythingToValues(params)
 	if err != nil {