Address review comments

Signed-off-by: Tushar Goel <tushar.goel.dav@gmail.com>

Author: TG1999

src/python_inspector/resolve_cli.py

@@ -208,6 +208,14 @@ def resolve_dependencies(
 
         python-inspector --spec "flask==2.1.2" --json -
     """
+    if not (json_output or pdt_output):
+        click.secho("No output file specified. Use --json or --json-pdt.", err=True)
+        ctx.exit(1)
+
+    if json_output and pdt_output:
+        click.secho("Only one of --json or --json-pdt can be used.", err=True)
+        ctx.exit(1)
+
     resolver_api(
         requirement_files=requirement_files,
         setup_py_file=setup_py_file,
@@ -264,11 +272,6 @@ def resolver_api(
     more ``requirement_files``, one or more ``specifiers`` and one setuptools
     ``setup_py_file`` file and save the results as JSON to FILE.
     """
-    if not (json_output or pdt_output):
-        raise_error("No output file specified. Use --json or --json-pdt.", ctx=ctx)
-
-    if json_output and pdt_output:
-        raise_error("Only one of --json or --json-pdt can be used.", ctx=ctx)
 
     if verbose:
         print_message("Resolving dependencies...", ctx=ctx)
@@ -423,10 +426,11 @@ def resolver_api(
         )
 
     if not ctx:
-        if json_output:
-            json_output = open(file=json_output, mode="w", encoding="utf-8")
-        if pdt_output:
-            pdt_output = open(file=pdt_output, mode="w", encoding="utf-8")
+        return dict(
+            headers=headers,
+            requirements=requirements,
+            resolved_dependencies=resolved_dependencies,
+        )
 
     if json_output:
         write_output(

tests/data/test-api-pdt-expected.json

@@ -1,47 +1,76 @@
-[
-  {
-    "key": "flask",
-    "package_name": "flask",
-    "installed_version": "2.1.2",
-    "dependencies": [
-      {
-        "key": "click",
-        "package_name": "click",
-        "installed_version": "8.1.3",
-        "dependencies": []
-      },
-      {
-        "key": "itsdangerous",
-        "package_name": "itsdangerous",
-        "installed_version": "2.1.2",
-        "dependencies": []
-      },
-      {
-        "key": "jinja2",
-        "package_name": "jinja2",
-        "installed_version": "3.1.2",
-        "dependencies": [
-          {
-            "key": "markupsafe",
-            "package_name": "markupsafe",
-            "installed_version": "2.1.1",
-            "dependencies": []
-          }
-        ]
-      },
-      {
-        "key": "werkzeug",
-        "package_name": "werkzeug",
-        "installed_version": "2.2.2",
-        "dependencies": [
-          {
-            "key": "markupsafe",
-            "package_name": "markupsafe",
-            "installed_version": "2.1.1",
-            "dependencies": []
-          }
-        ]
-      }
-    ]
-  }
-]
+{
+  "headers": {
+    "tool_name": "python-inspector",
+    "tool_homepageurl": "https://github.com/nexB/python-inspector",
+    "tool_version": "0.6.5",
+    "options": [
+      "specifiers- flask==2.1.2",
+      "index_urls- https://pypi.org/simple",
+      "python-version 3.10",
+      "operating-system linux",
+      "json "
+    ],
+    "notice": "Dependency tree generated with python-inspector.\npython-inspector is a free software tool from nexB Inc. and others.\nVisit https://github.com/nexB/scancode-toolkit/ for support and download.",
+    "warnings": [],
+    "errors": []
+  },
+  "requirements": [
+    {
+      "purl": "pkg:pypi/flask@2.1.2",
+      "extracted_requirement": "flask==2.1.2",
+      "scope": "install",
+      "is_runtime": true,
+      "is_optional": false,
+      "is_resolved": true,
+      "resolved_package": {},
+      "extra_data": {}
+    }
+  ],
+  "resolved_dependencies": [
+    {
+      "key": "flask",
+      "package_name": "flask",
+      "installed_version": "2.1.2",
+      "dependencies": [
+        {
+          "key": "click",
+          "package_name": "click",
+          "installed_version": "8.1.3",
+          "dependencies": []
+        },
+        {
+          "key": "itsdangerous",
+          "package_name": "itsdangerous",
+          "installed_version": "2.1.2",
+          "dependencies": []
+        },
+        {
+          "key": "jinja2",
+          "package_name": "jinja2",
+          "installed_version": "3.1.2",
+          "dependencies": [
+            {
+              "key": "markupsafe",
+              "package_name": "markupsafe",
+              "installed_version": "2.1.1",
+              "dependencies": []
+            }
+          ]
+        },
+        {
+          "key": "werkzeug",
+          "package_name": "werkzeug",
+          "installed_version": "2.2.2",
+          "dependencies": [
+            {
+              "key": "markupsafe",
+              "package_name": "markupsafe",
+              "installed_version": "2.1.1",
+              "dependencies": []
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}