- Adding unit tests for Server

examples/sample_dag.json

@@ -1,4 +1,15 @@
 {
+  "parameters": {
+    "SOURCE": [
+      "a",
+      "b",
+      "c"
+    ],
+    "DATE": [
+      "2021-01-01",
+      "2021-01-02"
+    ]
+  },
   "tasks": [
     {
       "name": "pull_data_a",
@@ -8,7 +19,9 @@
       "command": "/path/to/pull.sh --date {{DATE}} --source {{SOURCE}}_A",
       "verification_command": "/path/to/pull_verify.sh --date {{DATE}} --source {{SOURCE}}_A",
       "timeout_seconds": 30,
-      "children": [ "merge_data" ]
+      "children": [
+        "merge_data"
+      ]
     },
     {
       "name": "pull_data_b",
@@ -18,7 +31,9 @@
       "command": "/path/to/pull.sh --date {{DATE}} --source {{SOURCE}}_B",
       "verification_command": "/path/to/pull_verify.sh --date {{DATE}} --source {{SOURCE}}_B",
       "timeout_seconds": 30,
-      "children": [ "merge_data" ]
+      "children": [
+        "merge_data"
+      ]
     },
     {
       "name": "merge_data",