modis-crawler-utils

crawler-utils

Scrapy utils for Modis crawlers projects.

MongoDB

Some utils connected with mongodb.

MongoDBPipeline - pipeline for saving items in mongodb.

Params:

• MONGODB_SERVER - address of mongodb database.
• MONGODB_PORT - port of mongodb database.
• MONGODB_DB - database where to save data.
• MONGODB_USERNAME - username for authentication in MONGODB_DB database.
• MONGODB_PWD - password for authentication.
• DEFAULT_MONGODB_COLLECTION - default collection where to save data (default value is test).
• MONGODB_COLLECTION_KEY - key of item which identifies items collection name (MONGO_COLLECTION) where to save item (default value is collection).
• MONGODB_UNIQUE_KEY - key of item which identifies item

Kafka

Some utils connected with kafka.

KafkaPipeline - pipeline for pushing items into kafka.

Pipeline outputs data into stream with name {RESOURCE_TAG}.{DATA_TYPE}. Where RESOURCE_TAG is tag of resource from which data is crawled and DATA_TYPE is type of data crawled: data, post, comment, like, user, friend, share, member, news, community.

Params:

• KAFKA_ADDRESS - address of kafka broker.
• KAFKA_KEY - key of item which is put into kafka record key.
• KAFKA_RESOURCE_TAG_KEY - key of item which identifies item RESOURCE_TAG (default value is platform)
• KAFKA_DEFAULT_RESOURCE_TAG - default RESOURCE_TAG for crawled items without KAFKA_RESOURCE_TAG_KEY (default value is crawler)
• KAFKA_DATA_TYPE_KEY - key of item from which identifies item DATA_TYPE (default value is type).
• KAFKA_DEFAULT_DATA_TYPE - default DATA_TYPE for crawled items without KAFKA_DATA_TYPE_KEY (default value is data).
• KAFKA_COMPRESSION_TYPE - type of data compression in kafka for example gzip.

OpenSearch

OpenSearchRequestsDownloaderMiddleware transforms request-response pair into an item, and then sends it to the OpenSearch.

Settings:

`OPENSEARCH_REQUESTS_SETTINGS` - dict specifying OpenSearch client connections:
    "hosts": Optional[str | list[str]] = "localhost:9200" - hosts with opensearch endpoint,
    "timeout": Optional[int] = 60 - timeout of connections,
    "http_auth": Optional[tuple[str, str]] = None - HTTP authentication if needed,
    "port": Optional[int] = 443 - access port if not specified in hosts,
    "use_ssl": Optional[bool] = True - usage of SSL,
    "verify_certs": Optional[bool] = False - verifying certificates,
    "ssl_show_warn": Optional[bool] = False - show SSL warnings,
    "ca_certs": Optional[str] = None - CA certificate path,
    "client_key": Optional[str] = None - client key path,
    "client_cert": Optional[str] = None - client certificate path,
    "buffer_length": Optional[int] = 500 - number of items in OpenSearchStorage's buffer.

`OPENSEARCH_REQUESTS_INDEX`: Optional[str] = "scrapy-job-requests" - index in OpenSearch.

See an example in examples/opensearch.

CaptchaDetection

Captcha detection middleware for scrapy crawlers. It gets the HTML code from the response (if present), sends it to the captcha detection web-server and logs the result.

If you don't want to check exact response if it has captcha, provide meta-key dont_check_captcha with True value.

The middleware must be set up with higher precedence (lower number) than RetryMiddleware:

DOWNLOADER_MIDDLEWARES = {
    "crawler_utils.CaptchaDetectionDownloaderMiddleware": 549,  # By default, RetryMiddleware has 550
}

Middleware settings:

• ENABLE_CAPTCHA_DETECTOR: bool = True. Whether to enable captcha detection.
• CAPTCHA_SERVICE_URL: str. For an example: http://127.0.0.1:8000

Sentry logging

You may want to log exceptions during crawling to your Sentry. Use the crawler_utils.sentry_logging.SentryLoggingExtension for this. Note that sentry_sdk wants to be loaded as earlier as possible. To satisfy this condition make the extension with negative order:

EXTENSIONS = {
    # Load SentryLogging extension before other extensions.
    "crawler_utils.sentry_logging.SentryLoggingExtension": -1,
}

Settings:

SENTRY_DSN: str - Sentry's DSN, where to send events.
SENTRY_SAMPLE_RATE: float = 1.0 - sample rate for error events. Must be in range from 0.0 to 1.0.
SENTRY_TRACES_SAMPLE_RATE: float = 1.0 - the percentage chance a given transaction will be sent to Sentry.
SENTRY_ATTACH_STACKTRACE: bool = False - whether to attach stacktrace for error events.
SENTRY_MAX_BREADCRUMBS: int = 10 - max breadcrumbs to capture with Sentry.

For an example, check examples/sentry_logging.