Add API function for using cleanly as a library #39

Reference: #39
Signed-off-by: Tushar Goel <tushar.goel.dav@gmail.com>

Author: TG1999

CHANGELOG.rst

@@ -1,6 +1,11 @@
 Changelog
 =========
 
+v0.6.6
+------
+
+- Add API function for using cleanly as a library.
+
 v0.6.5
 ------
 

src/python_inspector/resolve_cli.py

@@ -207,16 +207,70 @@ 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)
+    resolver_api(
+        requirement_files=requirement_files,
+        setup_py_file=setup_py_file,
+        specifiers=specifiers,
+        python_version=python_version,
+        operating_system=operating_system,
+        index_urls=index_urls,
+        json_output=json_output,
+        pdt_output=pdt_output,
+        netrc_file=netrc_file,
+        max_rounds=max_rounds,
+        use_cached_index=use_cached_index,
+        use_pypi_json_api=use_pypi_json_api,
+        verbose=verbose,
+        ctx=ctx,
+    )
+
+
+def raise_error(message, ctx):
+    """Raise error."""
+    if ctx:
+        click.secho(message, err=True)
         ctx.exit(1)
+    else:
+        raise ValueError(message)
+
+
+def print_message(message, ctx):
+    """Print message."""
+    if ctx:
+        click.secho(message)
+    else:
+        print(message)
+
+
+def resolver_api(
+    requirement_files=[],
+    setup_py_file=None,
+    specifiers=[],
+    python_version=DEFAULT_PYTHON_VERSION,
+    operating_system="linux",
+    index_urls=tuple([PYPI_SIMPLE_URL]),
+    json_output=None,
+    pdt_output=None,
+    netrc_file=None,
+    max_rounds=200000,
+    use_cached_index=False,
+    use_pypi_json_api=False,
+    verbose=False,
+    ctx=None,
+):
+    """
+    Resolve the dependencies for the package requirements listed in one or
+    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:
-        click.secho("Only one of --json or --json-pdt can be used.", err=True)
-        ctx.exit(1)
+        raise_error("Only one of --json or --json-pdt can be used.", ctx=ctx)
 
     if verbose:
-        click.secho(f"Resolving dependencies...")
+        print_message("Resolving dependencies...", ctx=ctx)
 
     if netrc_file:
         if not os.path.exists(netrc_file):
@@ -231,7 +285,7 @@ def resolve_dependencies(
 
     if netrc_file:
         if verbose:
-            click.secho(f"Using netrc file {netrc_file}")
+            print_message(f"Using netrc file {netrc_file}", ctx=ctx)
         netrc = Netrc(file=netrc_file)
     else:
         netrc = None
@@ -262,35 +316,33 @@ def resolve_dependencies(
             python_version=get_python_version_from_env_tag(python_version),
             python_requires=python_requires,
         ):
-            click.secho(
+            raise_error(
                 f"Python version {get_python_version_from_env_tag(python_version)} "
                 f"is not compatible with setup.py {setup_py_file} "
                 f"python_requires {python_requires}",
-                err=True,
+                ctx=ctx,
             )
-            ctx.exit(1)
 
         for dep in package_data.dependencies:
             # TODO : we need to handle to all the scopes
             if dep.scope == "install":
                 direct_dependencies.append(dep)
 
     if not direct_dependencies:
-        click.secho("Error: no requirements requested.")
-        ctx.exit(1)
+        raise_error("Error: no requirements requested.", ctx=ctx)
 
     if verbose:
-        click.secho("direct_dependencies:")
+        print_message("direct_dependencies:", ctx=ctx)
         for dep in direct_dependencies:
-            click.secho(f" {dep}")
+            print_message(f" {dep}", ctx=ctx)
 
     # create a resolution environments
     environment = utils_pypi.Environment.from_pyver_and_os(
         python_version=python_version, operating_system=operating_system
     )
 
     if verbose:
-        click.secho(f"environment: {environment}")
+        print_message(f"environment: {environment}", ctx=ctx)
 
     repos = []
     if not use_pypi_json_api:
@@ -316,9 +368,9 @@ def resolve_dependencies(
                 repos.append(repo)
 
     if verbose:
-        click.secho("repos:")
+        print_message("repos:", ctx=ctx)
         for repo in repos:
-            click.secho(f" {repo}")
+            print_message(f" {repo}", ctx=ctx)
 
     # resolve dependencies proper
     requirements, resolved_dependencies = resolve(
@@ -331,12 +383,20 @@ def resolve_dependencies(
         pdt_output=pdt_output,
     )
 
-    cli_options = [f"--requirement {rf}" for rf in requirement_files]
-    cli_options += [f"--specifier {sp}" for sp in specifiers]
-    cli_options += [f"--index-url {iu}" for iu in index_urls]
-    cli_options += [f"--python-version {python_version}"]
-    cli_options += [f"--operating-system {operating_system}"]
-    cli_options += ["--json <file>"]
+    if ctx:
+        options = [f"--requirement {rf}" for rf in requirement_files]
+        options += [f"--specifier {sp}" for sp in specifiers]
+        options += [f"--index-url {iu}" for iu in index_urls]
+        options += [f"--python-version {python_version}"]
+        options += [f"--operating-system {operating_system}"]
+        options += ["--json <file>"]
+    else:
+        options = [f"requirement_files- {rf}" for rf in requirement_files]
+        options += [f"specifiers- {sp}" for sp in specifiers]
+        options += [f"index_urls- {iu}" for iu in index_urls]
+        options += [f"python-version {python_version}"]
+        options += [f"operating-system {operating_system}"]
+        options += [f"json "]
 
     notice = (
         "Dependency tree generated with python-inspector.\n"
@@ -348,12 +408,18 @@ def resolve_dependencies(
         tool_name="python-inspector",
         tool_homepageurl="https://github.com/nexB/python-inspector",
         tool_version=__version__,
-        options=cli_options,
+        options=options,
         notice=notice,
         warnings=[],
         errors=[],
     )
 
+    if not ctx:
+        if json_output:
+            json_output = open(json_output, "w")
+        if pdt_output:
+            pdt_output = open(pdt_output, "w")
+
     if json_output:
         write_output(
             headers=headers,
@@ -372,7 +438,7 @@ def resolve_dependencies(
         )
 
     if verbose:
-        click.secho("done!")
+        print_message("done!", ctx=ctx)
 
 
 def resolve(
@@ -445,7 +511,6 @@ def write_output(headers, requirements, resolved_dependencies, json_output, pdt_
         )
     else:
         output = resolved_dependencies
-
     json.dump(output, json_output, indent=2)
     return output
 

tests/data/test-api-expected.json

@@ -0,0 +1,88 @@
+{
+  "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": [
+    {
+      "package": "pkg:pypi/click@8.1.3",
+      "dependencies": [],
+      "wheel_urls": [
+        "https://files.pythonhosted.org/packages/c2/f1/df59e28c642d583f7dacffb1e0965d0e00b218e0186d7858ac5233dce840/click-8.1.3-py3-none-any.whl"
+      ],
+      "sdist_url": "https://files.pythonhosted.org/packages/59/87/84326af34517fca8c58418d148f2403df25303e02736832403587318e9e8/click-8.1.3.tar.gz"
+    },
+    {
+      "package": "pkg:pypi/flask@2.1.2",
+      "dependencies": [
+        "pkg:pypi/click@8.1.3",
+        "pkg:pypi/itsdangerous@2.1.2",
+        "pkg:pypi/jinja2@3.1.2",
+        "pkg:pypi/werkzeug@2.2.2"
+      ],
+      "wheel_urls": [
+        "https://files.pythonhosted.org/packages/ba/76/e9580e494eaf6f09710b0f3b9000c9c0363e44af5390be32bb0394165853/Flask-2.1.2-py3-none-any.whl"
+      ],
+      "sdist_url": "https://files.pythonhosted.org/packages/d3/3c/94f38d4db919a9326a706ad56f05a7e6f0c8f7b7d93e2997cca54d3bc14b/Flask-2.1.2.tar.gz"
+    },
+    {
+      "package": "pkg:pypi/itsdangerous@2.1.2",
+      "dependencies": [],
+      "wheel_urls": [
+        "https://files.pythonhosted.org/packages/68/5f/447e04e828f47465eeab35b5d408b7ebaaaee207f48b7136c5a7267a30ae/itsdangerous-2.1.2-py3-none-any.whl"
+      ],
+      "sdist_url": "https://files.pythonhosted.org/packages/7f/a1/d3fb83e7a61fa0c0d3d08ad0a94ddbeff3731c05212617dff3a94e097f08/itsdangerous-2.1.2.tar.gz"
+    },
+    {
+      "package": "pkg:pypi/jinja2@3.1.2",
+      "dependencies": [
+        "pkg:pypi/markupsafe@2.1.1"
+      ],
+      "wheel_urls": [
+        "https://files.pythonhosted.org/packages/bc/c3/f068337a370801f372f2f8f6bad74a5c140f6fda3d9de154052708dd3c65/Jinja2-3.1.2-py3-none-any.whl"
+      ],
+      "sdist_url": "https://files.pythonhosted.org/packages/7a/ff/75c28576a1d900e87eb6335b063fab47a8ef3c8b4d88524c4bf78f670cce/Jinja2-3.1.2.tar.gz"
+    },
+    {
+      "package": "pkg:pypi/markupsafe@2.1.1",
+      "dependencies": [],
+      "wheel_urls": [
+        "https://files.pythonhosted.org/packages/9e/82/2e089c6f34e77c073aa5a67040d368aac0dfb9b8ccbb46d381452c26fc33/MarkupSafe-2.1.1-cp310-cp310-manylinux_2_17_x86_64.manylinux2014_x86_64.whl"
+      ],
+      "sdist_url": "https://files.pythonhosted.org/packages/1d/97/2288fe498044284f39ab8950703e88abbac2abbdf65524d576157af70556/MarkupSafe-2.1.1.tar.gz"
+    },
+    {
+      "package": "pkg:pypi/werkzeug@2.2.2",
+      "dependencies": [
+        "pkg:pypi/markupsafe@2.1.1"
+      ],
+      "wheel_urls": [
+        "https://files.pythonhosted.org/packages/c8/27/be6ddbcf60115305205de79c29004a0c6bc53cec814f733467b1bb89386d/Werkzeug-2.2.2-py3-none-any.whl"
+      ],
+      "sdist_url": "https://files.pythonhosted.org/packages/f8/c1/1c8e539f040acd80f844c69a5ef8e2fccdf8b442dabb969e497b55d544e1/Werkzeug-2.2.2.tar.gz"
+    }
+  ]
+}

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

@@ -0,0 +1,47 @@
+[
+  {
+    "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": []
+          }
+        ]
+      }
+    ]
+  }
+]