fixes to API and return format

docs/api/wallet-rpc.yaml

@@ -127,7 +127,11 @@ paths:
     get:
       summary: get latest report on yield generating activity
       operationId: yieldgenreport
-      description: get list of coinjoins taken part in as maker (across all wallets)
+      description: "Get list of coinjoins taken part in as maker (across all wallets).
+      Data returned as list of strings, each one in the same comma separated format as found in yigen-statement.csv.
+      Note that this returns all lines in the file, including the lines that are only present to represent the starting
+      of a bot. Those lines contain the word Connected and can be thus discarded.
+      The header line is also delivered and so can be ignored as per the client requirements."
       responses:
         '200':
           $ref: "#/components/responses/YieldGenReport-200-OK"
@@ -577,6 +581,11 @@ components:
           items:
             type: string
             example: wallet.jmdat
+    YieldGenReportResponse:
+      type: array
+      items:
+        type: string
+        example: "2021/10/26 16:40:21,133986791,1,200000000,2680,2680,0.08,"
     SessionResponse:
       type: object
       required:
@@ -893,6 +902,12 @@ components:
         application/json:
           schema:
             $ref: "#/components/schemas/FreezeResponse"
+    YieldGenReport-200-OK:
+      description: "get list of coinjoins taken part in as maker (across all wallets)"
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/YieldGenReportResponse"
     202-Accepted:
       description: The request has been submitted successfully for processing, but the processing has not been completed. 
     # Clientside error responses

jmclient/jmclient/wallet_rpc.py

@@ -611,12 +611,18 @@ class JMWalletDaemon(Service):
             return make_jmwalletd_response(request, status=202)
 
         def get_json_yigen_report(self):
+            """ Returns a json object whose contents are:
+            a list of strings, each string is a comma separated record of
+            a coinjoin event, directly read from yigen-statement.csv without
+            further processing.
+            """
             try:
-                datadir = os.path.join(jm_single().config.datadir, "logs")
-                with open(os.path.join(datadir, "yigen-statement.csv"), "rb") as f:
-                    yigen_data_raw = f.readlines()
-                return json.loads(yigen_data_raw)
-            except:
+                datadir = os.path.join(jm_single().datadir, "logs")
+                with open(os.path.join(datadir, "yigen-statement.csv"), "r") as f:
+                    yigen_data = f.readlines()
+                return yigen_data
+            except Exception as e:
+                jlog.warn("Yigen report failed to find file: {}".format(repr(e)))
                 raise YieldGeneratorDataUnreadable()
 
         @app.route('/wallet/yieldgen/report', methods=['GET'])