feat: implement multiple version for nodejs lib (#504)

* feat: synthool generate src/index for nodejs client library

* fix the linters

* merge upstream

* remove '-' in jinja tempalte

* rename the functions

* add try, finally to avoid change direcory

* optional for versions and default verison

Author: summer-ji-eng

synthtool/gcp/common.py

@@ -92,6 +92,13 @@ def node_library(self, **kwargs) -> Path:
 
         kwargs["metadata"] = node.template_metadata()
         kwargs["publish_token"] = node.get_publish_token(kwargs["metadata"]["name"])
+
+        # generate root-level `src/index.ts` to export multiple versions and its default clients
+        if kwargs["versions"] and kwargs["default_version"]:
+            node.generate_index_ts(
+                versions=kwargs["versions"], default_version=kwargs["default_version"]
+            )
+
         return self._generic_library("node_library", **kwargs)
 
     def php_library(self, **kwargs) -> Path:

synthtool/gcp/templates/node_split_library/index.ts.j2

@@ -0,0 +1,24 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ** This file is automatically generated by synthtool. **
+// ** https://github.com/googleapis/synthtool **
+// ** All changes to this file may be overwritten. **
+
+{% for version in versions %}import * as {{ version }} from './{{ version}}';{{ "\n" }}{% endfor %}
+{% for client in clients %}const {{ client }} = {{ default_version }}.{{ client }};{{ "\n" }}{% endfor %}
+export {{ "{" }}{{ versions|join(', ')}}, {{ clients|join(', ')}}{{ "}" }};
+export default {{ "{" }}{{ versions|join(', ')}}, {{ clients|join(', ')}}{{ "}" }};
+import * as protos from '../protos/protos';
+export {protos};

synthtool/languages/node.py

@@ -13,10 +13,13 @@
 # limitations under the License.
 
 import json
-from typing import Any, Dict
+from jinja2 import FileSystemLoader, Environment
+from pathlib import Path
+import re
+from synthtool import log, shell
 from synthtool.sources import git
 from synthtool.gcp import samples, snippets
-from synthtool import log, shell
+from typing import Any, Dict, List
 
 _REQUIRED_FIELDS = ["name", "repository"]
 
@@ -94,6 +97,67 @@ def get_publish_token(package_name: str):
     return package_name.strip("@").replace("/", "-") + "-npm-token"
 
 
+def extract_clients(filePath: Path) -> List[str]:
+    """
+    parse the client name from index.ts file
+
+    Args:
+        filePath: the path of index.ts.
+    Returns:
+        Array of client name string extract from index.ts file.
+    """
+    with open(filePath, "r") as fh:
+        content = fh.read()
+    return re.findall(r"\{(.*Client)\}", content)
+
+
+def generate_index_ts(versions: List[str], default_version: str) -> None:
+    """
+    generate src/index.ts to export the client name and versions in the client library.
+
+    Args:
+      versions: the list of versions, like: ['v1', 'v1beta1', ...]
+      default_version: a stable version provided by API producer. It must exist in argument versions.
+    Return:
+      True/False: return true if successfully generate src/index.ts, vice versa.
+    """
+    # sanitizer the input arguments
+    if len(versions) < 1:
+        err_msg = (
+            "List of version can't be empty, it must contain default version at least."
+        )
+        log.error(err_msg)
+        raise AttributeError(err_msg)
+    if default_version not in versions:
+        err_msg = f"Version {versions} must contain default version {default_version}."
+        log.error(err_msg)
+        raise AttributeError(err_msg)
+
+    # compose default version's index.ts file path
+    versioned_index_ts_path = Path("src") / default_version / "index.ts"
+    clients = extract_clients(versioned_index_ts_path)
+    if not clients:
+        err_msg = f"No client is exported in the default version's({default_version}) index.ts ."
+        log.error(err_msg)
+        raise AttributeError(err_msg)
+
+    # compose template directory
+    template_path = (
+        Path(__file__).parent.parent / "gcp" / "templates" / "node_split_library"
+    )
+    template_loader = FileSystemLoader(searchpath=str(template_path))
+    template_env = Environment(loader=template_loader, keep_trailing_newline=True)
+    TEMPLATE_FILE = "index.ts.j2"
+    index_template = template_env.get_template(TEMPLATE_FILE)
+    # render index.ts content
+    output_text = index_template.render(
+        versions=versions, default_version=default_version, clients=clients
+    )
+    with open("src/index.ts", "w") as fh:
+        fh.write(output_text)
+    log.info("successfully generate `src/index.ts`")
+
+
 def install(hide_output=False):
     """
     Installs all dependencies for the current Node.js library.

tests/fixtures/node_templates/index_samples/multiple_index.ts

@@ -0,0 +1,20 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ** This file is automatically generated by gapic-generator-typescript. **
+// ** https://github.com/googleapis/gapic-generator-typescript **
+// ** All changes to this file may be overwritten. **
+
+export {StreamingVideoIntelligenceServiceClient} from './streaming_video_intelligence_service_client';
+export {VideoIntelligenceServiceClient} from './video_intelligence_service_client';

tests/fixtures/node_templates/index_samples/sample_index.ts

@@ -0,0 +1,27 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ** This file is automatically generated by synthtool. **
+// ** https://github.com/googleapis/synthtool **
+// ** All changes to this file may be overwritten. **
+
+import * as v1 from './v1';
+import * as v1beta1 from './v1beta1';
+
+const TextToSpeechClient = v1.TextToSpeechClient;
+
+export {v1, v1beta1, TextToSpeechClient};
+export default {v1, v1beta1, TextToSpeechClient};
+import * as protos from '../protos/protos';
+export {protos};

tests/fixtures/node_templates/index_samples/single_index.ts

@@ -0,0 +1,19 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ** This file is automatically generated by gapic-generator-typescript. **
+// ** https://github.com/googleapis/gapic-generator-typescript **
+// ** All changes to this file may be overwritten. **
+
+export {TextToSpeechClient} from './text_to_speech_client';

tests/fixtures/node_templates/index_samples/src/index.ts

@@ -0,0 +1,27 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ** This file is automatically generated by synthtool. **
+// ** https://github.com/googleapis/synthtool **
+// ** All changes to this file may be overwritten. **
+
+import * as v1 from './v1';
+import * as v1beta1 from './v1beta1';
+
+const TextToSpeechClient = v1.TextToSpeechClient;
+
+export {v1, v1beta1, TextToSpeechClient};
+export default {v1, v1beta1, TextToSpeechClient};
+import * as protos from '../protos/protos';
+export {protos};

tests/fixtures/node_templates/index_samples/src/invalid_index/index.ts

@@ -0,0 +1,17 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ** This file is automatically generated by gapic-generator-typescript. **
+// ** https://github.com/googleapis/gapic-generator-typescript **
+// ** All changes to this file may be overwritten. **

tests/fixtures/node_templates/index_samples/src/v1/index.ts

@@ -0,0 +1,19 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// ** This file is automatically generated by gapic-generator-typescript. **
+// ** https://github.com/googleapis/gapic-generator-typescript **
+// ** All changes to this file may be overwritten. **
+
+export {TextToSpeechClient} from './text_to_speech_client';

tests/test_node.py

@@ -17,6 +17,9 @@
 import os
 from pathlib import Path
 from synthtool.languages import node
+import pathlib
+import filecmp
+import pytest
 
 FIXTURES = Path(__file__).parent / "fixtures"
 
@@ -74,6 +77,102 @@ def test_no_samples():
     os.chdir(cwd)
 
 
+def test_extract_clients_no_file():
+    index_ts_path = pathlib.Path(
+        FIXTURES / "node_templates" / "index_samples" / "no_exist_index.ts"
+    )
+
+    with pytest.raises(FileNotFoundError):
+        clients = node.extract_clients(index_ts_path)
+        assert not clients
+
+
+def test_extract_single_clients():
+    index_ts_path = pathlib.Path(
+        FIXTURES / "node_templates" / "index_samples" / "single_index.ts"
+    )
+
+    clients = node.extract_clients(index_ts_path)
+
+    assert len(clients) == 1
+    assert clients[0] == "TextToSpeechClient"
+
+
+def test_extract_multiple_clients():
+    index_ts_path = pathlib.Path(
+        FIXTURES / "node_templates" / "index_samples" / "multiple_index.ts"
+    )
+
+    clients = node.extract_clients(index_ts_path)
+
+    assert len(clients) == 2
+    assert clients[0] == "StreamingVideoIntelligenceServiceClient"
+    assert clients[1] == "VideoIntelligenceServiceClient"
+
+
+def test_generate_index_ts():
+    cwd = os.getcwd()
+    try:
+        # use a non-nodejs template directory
+        os.chdir(FIXTURES / "node_templates" / "index_samples")
+        node.generate_index_ts(["v1", "v1beta1"], "v1")
+        generated_index_path = pathlib.Path(
+            FIXTURES / "node_templates" / "index_samples" / "src" / "index.ts"
+        )
+        sample_index_path = pathlib.Path(
+            FIXTURES / "node_templates" / "index_samples" / "sample_index.ts"
+        )
+        assert filecmp.cmp(generated_index_path, sample_index_path)
+    finally:
+        os.chdir(cwd)
+
+
+def test_generate_index_ts_empty_versions():
+    cwd = os.getcwd()
+    try:
+        # use a non-nodejs template directory
+        os.chdir(FIXTURES / "node_templates" / "index_samples")
+
+        with pytest.raises(AttributeError) as err:
+            node.generate_index_ts([], "v1")
+            assert "can't be empty" in err.args
+    finally:
+        os.chdir(cwd)
+
+
+def test_generate_index_ts_invalid_default_version():
+    cwd = os.getcwd()
+    try:
+        # use a non-nodejs template directory
+        os.chdir(FIXTURES / "node_templates" / "index_samples")
+        versions = ["v1beta1"]
+        default_version = "v1"
+
+        with pytest.raises(AttributeError) as err:
+            node.generate_index_ts(versions, default_version)
+            assert f"must contain default version {default_version}" in err.args
+    finally:
+        os.chdir(cwd)
+
+
+def test_generate_index_ts_no_clients():
+    cwd = os.getcwd()
+    try:
+        # use a non-nodejs template directory
+        os.chdir(FIXTURES / "node_templates" / "index_samples")
+        versions = ["v1", "v1beta1", "invalid_index"]
+        default_version = "invalid_index"
+
+        with pytest.raises(AttributeError) as err:
+            node.generate_index_ts(versions, default_version)
+            assert (
+                f"No client is exported in the default version's({default_version}) index.ts ."
+                in err.args
+            )
+    finally:
+        os.chdir(cwd)
+
+
 class TestPostprocess(TestCase):
     @patch("synthtool.shell.run")
     def test_install(self, shell_run_mock):