[VOL-4638] Add communication with VOLTHA NBI and the Olt app REST APIs
Change-Id: I6ccf5725a108b91f47dfc4c20e9614b38c71419a
diff --git a/internal/clients/olt_app.go b/internal/clients/olt_app.go
new file mode 100644
index 0000000..6e171b9
--- /dev/null
+++ b/internal/clients/olt_app.go
@@ -0,0 +1,137 @@
+/*
+* Copyright 2022-present Open Networking Foundation
+
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+
+* http://www.apache.org/licenses/LICENSE-2.0
+
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+ */
+
+package clients
+
+import (
+ "context"
+ "fmt"
+ "io"
+ "net/http"
+ "time"
+
+ "github.com/opencord/voltha-lib-go/v7/pkg/log"
+)
+
+const (
+ oltAppHttpRequestTimeout = time.Second * 10
+ oltAppBackoffInterval = time.Second * 10
+)
+
+type OltAppClient struct {
+ httpClient *http.Client
+ endpoint string
+ username string
+ password string
+}
+
+type RestResponse struct {
+ Body string
+ Code int
+}
+
+// Creates a new olt app client
+func NewOltAppClient(endpoint string, user string, pass string) *OltAppClient {
+ return &OltAppClient{
+ httpClient: &http.Client{
+ Timeout: oltAppHttpRequestTimeout,
+ },
+ endpoint: endpoint,
+ username: user,
+ password: pass,
+ }
+}
+
+func (c *OltAppClient) CheckConnection(ctx context.Context) error {
+ logger.Debugw(ctx, "checking-connection-to-onos-olt-app-api", log.Fields{"endpoint": c.endpoint})
+
+ for {
+ if resp, err := c.GetStatus(); err == nil {
+ logger.Debug(ctx, "onos-olt-app-api-reachable")
+ break
+ } else {
+ logger.Warnw(ctx, "onos-olt-app-api-not-ready", log.Fields{
+ "err": err,
+ "response": resp,
+ })
+ }
+
+ //Wait a bit before trying again
+ select {
+ case <-ctx.Done():
+ return fmt.Errorf("onos-olt-app-connection-stopped-due-to-context-done")
+ case <-time.After(oltAppBackoffInterval):
+ continue
+ }
+ }
+
+ return nil
+}
+
+func (c *OltAppClient) makeRequest(method string, url string) (RestResponse, error) {
+ result := RestResponse{Code: 0}
+
+ req, err := http.NewRequest(method, url, nil)
+ if err != nil {
+ return result, fmt.Errorf("cannot-create-request: %s", err)
+ }
+
+ req.SetBasicAuth(c.username, c.password)
+
+ resp, err := c.httpClient.Do(req)
+ if err != nil {
+ return result, fmt.Errorf("cannot-get-response: %s", err)
+ }
+ defer resp.Body.Close()
+
+ buffer, err := io.ReadAll(resp.Body)
+ if err != nil {
+ return result, fmt.Errorf("error-while-reading-response-body: %s", err)
+ }
+
+ result.Body = string(buffer)
+ result.Code = resp.StatusCode
+
+ if result.Code != http.StatusOK {
+ return result, fmt.Errorf("status-code-not-ok: %s %s %d", method, url, result.Code)
+ }
+
+ return result, nil
+}
+
+func (c *OltAppClient) GetStatus() (RestResponse, error) {
+ method := http.MethodGet
+ url := fmt.Sprintf("http://%s/onos/olt/oltapp/status", c.endpoint)
+
+ return c.makeRequest(method, url)
+}
+
+//NOTE: if methods are used to retrieve more complex information
+//it may be better to return an already deserialized structure
+//instead of the current RestResponse
+func (c *OltAppClient) ProvisionSubscriber(device string, port uint32) (RestResponse, error) {
+ method := http.MethodPost
+ url := fmt.Sprintf("http://%s/onos/olt/oltapp/%s/%d", c.endpoint, device, port)
+
+ return c.makeRequest(method, url)
+}
+
+func (c *OltAppClient) RemoveSubscriber(device string, port uint32) (RestResponse, error) {
+ method := http.MethodDelete
+ url := fmt.Sprintf("http://%s/onos/olt/oltapp/%s/%d", c.endpoint, device, port)
+
+ return c.makeRequest(method, url)
+}