Draft for Dynamic provider endpoints. Need a feedback about the function modifications in Provider.ts. Need to do unit tests.

src/provider/Provider.ts

@@ -21,6 +21,7 @@ const apiPath = '/api/v1/services'
 export class Provider extends Instantiable {
   public nonce: string
   private baseUrl: string
+  public validServiceEndpoints: any
 
   public get url(): string {
     return this.baseUrl
@@ -186,6 +187,42 @@ export class Provider extends Instantiable {
     return destination
   }
 
+  public async getServiceEndpoints() {
+    let fetch: any
+    fetch = this.ocean.utils.fetch.get(this.url)
+    if (this.validServiceEndpoints != null) {
+      this.validServiceEndpoints = await fetch
+        .then((response: Response) => {
+          if (response.ok) {
+            return response.json()
+          }
+
+          this.logger.error('Finding the service endpoints failed:', response.status, response.statusText)
+
+          return null
+        })
+        .catch((error: Error) => {
+          this.logger.error('Error with service endpoints')
+          this.logger.error(error.message)
+          throw error
+        })
+    }
+      return this.validServiceEndpoints;
+}
+
+public getEndpointURL(
+  serviceName : string
+) : string {
+  var method: string
+  var urlEndpoint: string
+  this.validServiceEndpoints = this.getServiceEndpoints()
+  method = this.validServiceEndpoints['serviceEndpoints'][0]
+  urlEndpoint = this.validServiceEndpoints['serviceEndpoints'][1]
+  urlEndpoint = urlEndpoint.replace(`${apiPath}`, '')
+  return `${this.getURI()}${urlEndpoint}`
+
+}
+
   public async compute(
     method: string,
     did: string,
@@ -242,7 +279,6 @@ export class Provider extends Instantiable {
     // 'algorithmDid': alg_ddo.did,
     // 'algorithmMeta': {},
     // 'algorithmDataToken': alg_data_token
-
     // switch fetch method
     let fetch
     switch (method) {
@@ -288,11 +324,13 @@ export class Provider extends Instantiable {
   }
 
   public getInitializeEndpoint(): string {
-    return `${this.url}${apiPath}/initialize`
+    //return `${this.url}${apiPath}/initialize`
+    return this.getEndpointURL('initialize')
   }
 
   public getNonceEndpoint(): string {
-    return `${this.url}${apiPath}/nonce`
+    //return `${this.url}${apiPath}/nonce`
+    return this.getEndpointURL('nonce')
   }
 
   public getConsumeEndpointPath(): string {
@@ -304,27 +342,46 @@ export class Provider extends Instantiable {
   }
 
   public getEncryptEndpoint(): string {
-    return `${this.url}${apiPath}/encrypt`
+    //return `${this.url}${apiPath}/encrypt`
+    return this.getEndpointURL('encrypt')
   }
 
   public getFileinfoEndpoint(): string {
-    return `${this.url}${apiPath}/fileinfo`
+    //return `${this.url}${apiPath}/fileinfo`
+    return this.getEndpointURL('fileinfo')
   }
 
   public getPublishEndpoint(): string {
     return `${this.url}${apiPath}/publish`
   }
 
-  public getComputeEndpointPath(): string {
-    return `${apiPath}/compute`
+  // public getComputeEndpointPath(): string {
+  //   return `${apiPath}/compute`
+  // }
+
+  // public getComputeEndpoint(): string {
+  //   return `${this.url}` + this.getComputeEndpointPath()
+  // }
+
+  public getComputeStatusJob(): string {
+    return this.getEndpointURL('computeStatus')
   }
 
-  public getComputeEndpoint(): string {
-    return `${this.url}` + this.getComputeEndpointPath()
+  public getStartComputeJob(): string {
+    return this.getEndpointURL('computeStart')
+  }
+
+  public getStopComputeJob(): string {
+    return this.getEndpointURL('computeStop')
+  }
+
+  public getDeleteComputeJob(): string {
+    return this.getEndpointURL('computeDelete')
   }
 
   public getDownloadEndpoint(): string {
-    return `${this.url}${apiPath}/download`
+    //return `${this.url}${apiPath}/download`
+    return this.getEndpointURL('download')
   }
 
   /** Check for a valid provider at URL