Google Search: Allow extracting items from SERP results (#78)

docs/reference/index.rst

@@ -52,5 +52,10 @@ Parameter mixins
 
 .. autoenum:: zyte_spider_templates.spiders.ecommerce.EcommerceCrawlStrategy
 
+.. autopydantic_model:: zyte_spider_templates.spiders.serp.SerpItemTypeParam
+    :exclude-members: model_computed_fields
+
+.. autoenum:: zyte_spider_templates.spiders.serp.SerpItemType
+
 .. autopydantic_model:: zyte_spider_templates.spiders.serp.SerpMaxPagesParam
     :exclude-members: model_computed_fields

setup.py

@@ -23,7 +23,7 @@
         "scrapy-spider-metadata>=0.2.0",
         "scrapy-zyte-api[provider]>=0.23.0",
         "web-poet>=0.17.1",
-        "zyte-common-items>=0.25.0",
+        "zyte-common-items>=0.26.2",
     ],
     classifiers=[
         "Development Status :: 3 - Alpha",

tests/test_serp.py

@@ -4,8 +4,13 @@
 from scrapy_spider_metadata import get_spider_metadata
 from scrapy_zyte_api.responses import ZyteAPITextResponse
 from w3lib.url import add_or_replace_parameter
+from zyte_common_items import Product
 
-from zyte_spider_templates.spiders.serp import GoogleSearchSpider
+from zyte_spider_templates.spiders.serp import (
+    ITEM_TYPE_CLASSES,
+    GoogleSearchSpider,
+    SerpItemType,
+)
 
 from . import get_crawler
 from .utils import assertEqualSpiderMetadata
@@ -259,6 +264,25 @@ def test_metadata():
                     "title": "Max Pages",
                     "type": "integer",
                 },
+                "item_type": {
+                    "anyOf": [{"type": "string"}, {"type": "null"}],
+                    "default": None,
+                    "description": (
+                        "If specified, follow organic search result links, "
+                        "and extract the selected data type from the target "
+                        "pages. Spider output items will be of the specified "
+                        "data type, not search engine results page items."
+                    ),
+                    "enum": [
+                        "article",
+                        "articleList",
+                        "forumThread",
+                        "jobPosting",
+                        "product",
+                        "productList",
+                    ],
+                    "title": "Follow and Extract",
+                },
                 "max_requests": {
                     "anyOf": [{"type": "integer"}, {"type": "null"}],
                     "default": 100,
@@ -457,3 +481,70 @@ def test_parse_serp():
     # The page_number parameter is required.
     with pytest.raises(TypeError):
         spider.parse_serp(response)  # type: ignore[call-arg]
+
+
+def test_item_type():
+    crawler = get_crawler()
+    spider = GoogleSearchSpider.from_crawler(
+        crawler, search_queries="foo bar", max_pages=43, item_type="product"
+    )
+    url = "https://www.google.com/search?q=foo+bar"
+    response = ZyteAPITextResponse.from_api_response(
+        api_response={
+            "serp": {
+                "organicResults": [
+                    {
+                        "description": "…",
+                        "name": "…",
+                        "url": f"https://example.com/{rank}",
+                        "rank": rank,
+                    }
+                    for rank in range(1, 11)
+                ],
+                "metadata": {
+                    "dateDownloaded": "2024-10-25T08:59:45Z",
+                    "displayedQuery": "foo bar",
+                    "searchedQuery": "foo bar",
+                    "totalOrganicResults": 99999,
+                },
+                "pageNumber": 1,
+                "url": url,
+            },
+            "url": url,
+        },
+    )
+    items = []
+    requests = []
+    for item_or_request in spider.parse_serp(response, page_number=42):
+        if isinstance(item_or_request, Request):
+            requests.append(item_or_request)
+        else:
+            items.append(item_or_request)
+    assert len(items) == 0
+    assert len(requests) == 11
+
+    assert requests[0].url == add_or_replace_parameter(url, "start", "420")
+    assert requests[0].cb_kwargs["page_number"] == 43
+
+    for rank in range(1, 11):
+        assert requests[rank].url == f"https://example.com/{rank}"
+        assert requests[rank].callback == spider.parse_result
+        assert requests[rank].meta == {
+            "crawling_logs": {"page_type": "product"},
+            "inject": [Product],
+        }
+
+
+def test_item_type_mappings():
+    # Ensure that all SerpItemType keys and values match.
+    for entry in SerpItemType:
+        assert entry.name == entry.value
+
+    # Ensure that the ITEM_TYPE_CLASSES dict maps all values from the
+    # corresponding enum except for serp.
+    actual_keys = set(ITEM_TYPE_CLASSES)
+    expected_keys = set(entry.value for entry in SerpItemType)
+    assert actual_keys == expected_keys
+
+    # Also ensure that no dict value is repeated.
+    assert len(actual_keys) == len(set(ITEM_TYPE_CLASSES.values()))

tox.ini

@@ -31,7 +31,7 @@ deps =
     scrapy-spider-metadata==0.2.0
     scrapy-zyte-api[provider]==0.23.0
     web-poet==0.17.1
-    zyte-common-items==0.25.0
+    zyte-common-items==0.26.2
 
 [testenv:mypy]
 deps =

zyte_spider_templates/spiders/serp.py

@@ -1,12 +1,23 @@
+from enum import Enum
 from typing import Any, Dict, Iterable, List, Optional, Union
 
 from pydantic import BaseModel, Field, field_validator
 from scrapy import Request
 from scrapy.settings import SETTINGS_PRIORITIES, BaseSettings
+from scrapy_poet import DummyResponse, DynamicDeps
 from scrapy_spider_metadata import Args
 from w3lib.url import add_or_replace_parameter
-from zyte_common_items import Serp
-
+from zyte_common_items import (
+    Article,
+    ArticleList,
+    ForumThread,
+    JobPosting,
+    Product,
+    ProductList,
+    Serp,
+)
+
+from ..documentation import document_enum
 from ..params import MaxRequestsParam
 from ._google_domains import GoogleDomain
 from .base import BaseSpider
@@ -48,6 +59,62 @@ class SerpMaxPagesParam(BaseModel):
     )
 
 
+@document_enum
+class SerpItemType(str, Enum):
+    article: str = "article"
+    """
+    Article data.
+    """
+
+    articleList: str = "articleList"
+    """
+    Article list data.
+    """
+
+    forumThread: str = "forumThread"
+    """
+    Forum thread data.
+    """
+
+    jobPosting: str = "jobPosting"
+    """
+    Job posting data.
+    """
+
+    product: str = "product"
+    """
+    Product data.
+    """
+
+    productList: str = "productList"
+    """
+    Product list data.
+    """
+
+
+ITEM_TYPE_CLASSES = {
+    SerpItemType.article: Article,
+    SerpItemType.articleList: ArticleList,
+    SerpItemType.forumThread: ForumThread,
+    SerpItemType.jobPosting: JobPosting,
+    SerpItemType.product: Product,
+    SerpItemType.productList: ProductList,
+}
+
+
+class SerpItemTypeParam(BaseModel):
+    item_type: Optional[SerpItemType] = Field(
+        title="Follow and Extract",
+        description=(
+            "If specified, follow organic search result links, and extract "
+            "the selected data type from the target pages. Spider output "
+            "items will be of the specified data type, not search engine "
+            "results page items."
+        ),
+        default=None,
+    )
+
+
 class GoogleDomainParam(BaseModel):
     domain: GoogleDomain = Field(
         title="Domain",
@@ -58,6 +125,7 @@ class GoogleDomainParam(BaseModel):
 
 class GoogleSearchSpiderParams(
     MaxRequestsParam,
+    SerpItemTypeParam,
     SerpMaxPagesParam,
     SearchQueriesParam,
     GoogleDomainParam,
@@ -132,4 +200,21 @@ def parse_serp(self, response, page_number) -> Iterable[Union[Request, Serp]]:
                 next_url = add_or_replace_parameter(serp.url, "start", str(next_start))
                 yield self.get_serp_request(next_url, page_number=page_number + 1)
 
-        yield serp
+        if self.args.item_type is None:
+            yield serp
+            return
+
+        for result in serp.organicResults:
+            yield response.follow(
+                result.url,
+                callback=self.parse_result,
+                meta={
+                    "crawling_logs": {"page_type": self.args.item_type.value},
+                    "inject": [ITEM_TYPE_CLASSES[self.args.item_type]],
+                },
+            )
+
+    def parse_result(
+        self, response: DummyResponse, dynamic: DynamicDeps
+    ) -> Iterable[Any]:
+        yield next(iter(dynamic.values()))