Module slack_sdk.webhook.client

Classes

class WebhookClient (url: str, timeout: int = 30, ssl: Optional[ssl.SSLContext] = None, proxy: Optional[str] = None, default_headers: Optional[Dict[str, str]] = None, user_agent_prefix: Optional[str] = None, user_agent_suffix: Optional[str] = None, logger: Optional[logging.Logger] = None, retry_handlers: Optional[List[RetryHandler]] = None)

API client for Incoming Webhooks and response_url

https://api.slack.com/messaging/webhooks

Args

url

Complete URL to send data (e.g., https://hooks.slack.com/XXX)

timeout

Request timeout (in seconds)

ssl

ssl.SSLContext to use for requests

proxy

Proxy URL (e.g., localhost:9000, http://localhost:9000)

default_headers

Request headers to add to all requests

user_agent_prefix

Prefix for User-Agent header value

user_agent_suffix

Suffix for User-Agent header value

logger

Custom logger

retry_handlers

Retry handlers

Expand source code

class WebhookClient:
    url: str
    timeout: int
    ssl: Optional[SSLContext]
    proxy: Optional[str]
    default_headers: Dict[str, str]
    logger: logging.Logger
    retry_handlers: List[RetryHandler]

    def __init__(
        self,
        url: str,
        timeout: int = 30,
        ssl: Optional[SSLContext] = None,
        proxy: Optional[str] = None,
        default_headers: Optional[Dict[str, str]] = None,
        user_agent_prefix: Optional[str] = None,
        user_agent_suffix: Optional[str] = None,
        logger: Optional[logging.Logger] = None,
        retry_handlers: Optional[List[RetryHandler]] = None,
    ):
        """API client for Incoming Webhooks and `response_url`

        https://api.slack.com/messaging/webhooks

        Args:
            url: Complete URL to send data (e.g., `https://hooks.slack.com/XXX`)
            timeout: Request timeout (in seconds)
            ssl: `ssl.SSLContext` to use for requests
            proxy: Proxy URL (e.g., `localhost:9000`, `http://localhost:9000`)
            default_headers: Request headers to add to all requests
            user_agent_prefix: Prefix for User-Agent header value
            user_agent_suffix: Suffix for User-Agent header value
            logger: Custom logger
            retry_handlers: Retry handlers
        """
        self.url = url
        self.timeout = timeout
        self.ssl = ssl
        self.proxy = proxy
        self.default_headers = default_headers if default_headers else {}
        self.default_headers["User-Agent"] = get_user_agent(user_agent_prefix, user_agent_suffix)
        self.logger = logger if logger is not None else logging.getLogger(__name__)
        self.retry_handlers = retry_handlers if retry_handlers is not None else default_retry_handlers()

        if self.proxy is None or len(self.proxy.strip()) == 0:
            env_variable = load_http_proxy_from_env(self.logger)
            if env_variable is not None:
                self.proxy = env_variable

    def send(
        self,
        *,
        text: Optional[str] = None,
        attachments: Optional[Sequence[Union[Dict[str, Any], Attachment]]] = None,
        blocks: Optional[Sequence[Union[Dict[str, Any], Block]]] = None,
        response_type: Optional[str] = None,
        replace_original: Optional[bool] = None,
        delete_original: Optional[bool] = None,
        unfurl_links: Optional[bool] = None,
        unfurl_media: Optional[bool] = None,
        metadata: Optional[Dict[str, Any]] = None,
        headers: Optional[Dict[str, str]] = None,
    ) -> WebhookResponse:
        """Performs a Slack API request and returns the result.

        Args:
            text: The text message
                (even when having blocks, setting this as well is recommended as it works as fallback)
            attachments: A collection of attachments
            blocks: A collection of Block Kit UI components
            response_type: The type of message (either 'in_channel' or 'ephemeral')
            replace_original: True if you use this option for response_url requests
            delete_original: True if you use this option for response_url requests
            unfurl_links: Option to indicate whether text url should unfurl
            unfurl_media: Option to indicate whether media url should unfurl
            metadata: Metadata attached to the message
            headers: Request headers to append only for this request

        Returns:
            Webhook response
        """
        return self.send_dict(
            # It's fine to have None value elements here
            # because _build_body() filters them out when constructing the actual body data
            body={
                "text": text,
                "attachments": attachments,
                "blocks": blocks,
                "response_type": response_type,
                "replace_original": replace_original,
                "delete_original": delete_original,
                "unfurl_links": unfurl_links,
                "unfurl_media": unfurl_media,
                "metadata": metadata,
            },
            headers=headers,
        )

    def send_dict(self, body: Dict[str, Any], headers: Optional[Dict[str, str]] = None) -> WebhookResponse:
        """Performs a Slack API request and returns the result.

        Args:
            body: JSON data structure (it's still a dict at this point),
                if you give this argument, body_params and files will be skipped
            headers: Request headers to append only for this request
        Returns:
            Webhook response
        """
        return self._perform_http_request(
            body=_build_body(body),
            headers=_build_request_headers(self.default_headers, headers),
        )

    def _perform_http_request(self, *, body: Dict[str, Any], headers: Dict[str, str]) -> WebhookResponse:
        body = json.dumps(body)
        headers["Content-Type"] = "application/json;charset=utf-8"

        if self.logger.level <= logging.DEBUG:
            self.logger.debug(f"Sending a request - url: {self.url}, body: {body}, headers: {headers}")

        url = self.url
        # NOTE: Intentionally ignore the `http_verb` here
        # Slack APIs accepts any API method requests with POST methods
        req = Request(method="POST", url=url, data=body.encode("utf-8"), headers=headers)
        resp = None
        last_error = None

        retry_state = RetryState()
        counter_for_safety = 0
        while counter_for_safety < 100:
            counter_for_safety += 1
            # If this is a retry, the next try started here. We can reset the flag.
            retry_state.next_attempt_requested = False

            try:
                resp = self._perform_http_request_internal(url, req)
                # The resp is a 200 OK response
                return resp

            except HTTPError as e:
                # read the response body here
                charset = e.headers.get_content_charset() or "utf-8"
                response_body: str = e.read().decode(charset)
                # As adding new values to HTTPError#headers can be ignored, building a new dict object here
                response_headers = dict(e.headers.items())
                resp = WebhookResponse(
                    url=url,
                    status_code=e.code,
                    body=response_body,
                    headers=response_headers,
                )
                if e.code == 429:
                    # for backward-compatibility with WebClient (v.2.5.0 or older)
                    if "retry-after" not in resp.headers and "Retry-After" in resp.headers:
                        resp.headers["retry-after"] = resp.headers["Retry-After"]
                    if "Retry-After" not in resp.headers and "retry-after" in resp.headers:
                        resp.headers["Retry-After"] = resp.headers["retry-after"]
                _debug_log_response(self.logger, resp)

                # Try to find a retry handler for this error
                retry_request = RetryHttpRequest.from_urllib_http_request(req)
                retry_response = RetryHttpResponse(
                    status_code=e.code,
                    headers={k: [v] for k, v in e.headers.items()},
                    data=response_body.encode("utf-8") if response_body is not None else None,
                )
                for handler in self.retry_handlers:
                    if handler.can_retry(
                        state=retry_state,
                        request=retry_request,
                        response=retry_response,
                        error=e,
                    ):
                        if self.logger.level <= logging.DEBUG:
                            self.logger.info(
                                f"A retry handler found: {type(handler).__name__} for {req.method} {req.full_url} - {e}"
                            )
                        handler.prepare_for_next_attempt(
                            state=retry_state,
                            request=retry_request,
                            response=retry_response,
                            error=e,
                        )
                        break

                if retry_state.next_attempt_requested is False:
                    return resp

            except Exception as err:
                last_error = err
                self.logger.error(f"Failed to send a request to Slack API server: {err}")

                # Try to find a retry handler for this error
                retry_request = RetryHttpRequest.from_urllib_http_request(req)
                for handler in self.retry_handlers:
                    if handler.can_retry(
                        state=retry_state,
                        request=retry_request,
                        response=None,
                        error=err,
                    ):
                        if self.logger.level <= logging.DEBUG:
                            self.logger.info(
                                f"A retry handler found: {type(handler).__name__} for {req.method} {req.full_url} - {err}"
                            )
                        handler.prepare_for_next_attempt(
                            state=retry_state,
                            request=retry_request,
                            response=None,
                            error=err,
                        )
                        self.logger.info(f"Going to retry the same request: {req.method} {req.full_url}")
                        break

                if retry_state.next_attempt_requested is False:
                    raise err

        if resp is not None:
            return resp
        raise last_error

    def _perform_http_request_internal(self, url: str, req: Request):
        opener: Optional[OpenerDirector] = None
        # for security (BAN-B310)
        if url.lower().startswith("http"):
            if self.proxy is not None:
                if isinstance(self.proxy, str):
                    opener = urllib.request.build_opener(
                        ProxyHandler({"http": self.proxy, "https": self.proxy}),
                        HTTPSHandler(context=self.ssl),
                    )
                else:
                    raise SlackRequestError(f"Invalid proxy detected: {self.proxy} must be a str value")
        else:
            raise SlackRequestError(f"Invalid URL detected: {url}")

        # NOTE: BAN-B310 is already checked above
        http_resp: Optional[HTTPResponse] = None
        if opener:
            http_resp = opener.open(req, timeout=self.timeout)  # skipcq: BAN-B310
        else:
            http_resp = urlopen(req, context=self.ssl, timeout=self.timeout)  # skipcq: BAN-B310
        charset: str = http_resp.headers.get_content_charset() or "utf-8"
        response_body: str = http_resp.read().decode(charset)
        resp = WebhookResponse(
            url=url,
            status_code=http_resp.status,
            body=response_body,
            headers=http_resp.headers,
        )
        _debug_log_response(self.logger, resp)
        return resp

Class variables

var default_headers : Dict[str, str]

var logger : logging.Logger

var proxy : Optional[str]

var retry_handlers : List[RetryHandler]

var ssl : Optional[ssl.SSLContext]

var timeout : int

var url : str

Methods

def send(self, *, text: Optional[str] = None, attachments: Optional[Sequence[Union[Dict[str, Any], Attachment]]] = None, blocks: Optional[Sequence[Union[Dict[str, Any], Block]]] = None, response_type: Optional[str] = None, replace_original: Optional[bool] = None, delete_original: Optional[bool] = None, unfurl_links: Optional[bool] = None, unfurl_media: Optional[bool] = None, metadata: Optional[Dict[str, Any]] = None, headers: Optional[Dict[str, str]] = None) ‑> WebhookResponse

Performs a Slack API request and returns the result.

Args

text

The text message (even when having blocks, setting this as well is recommended as it works as fallback)

attachments

A collection of attachments

blocks

A collection of Block Kit UI components

response_type

The type of message (either 'in_channel' or 'ephemeral')

replace_original

True if you use this option for response_url requests

delete_original

True if you use this option for response_url requests

unfurl_links

Option to indicate whether text url should unfurl

unfurl_media

Option to indicate whether media url should unfurl

metadata

Metadata attached to the message

headers

Request headers to append only for this request

Returns

Webhook response

Expand source code

def send(
    self,
    *,
    text: Optional[str] = None,
    attachments: Optional[Sequence[Union[Dict[str, Any], Attachment]]] = None,
    blocks: Optional[Sequence[Union[Dict[str, Any], Block]]] = None,
    response_type: Optional[str] = None,
    replace_original: Optional[bool] = None,
    delete_original: Optional[bool] = None,
    unfurl_links: Optional[bool] = None,
    unfurl_media: Optional[bool] = None,
    metadata: Optional[Dict[str, Any]] = None,
    headers: Optional[Dict[str, str]] = None,
) -> WebhookResponse:
    """Performs a Slack API request and returns the result.

    Args:
        text: The text message
            (even when having blocks, setting this as well is recommended as it works as fallback)
        attachments: A collection of attachments
        blocks: A collection of Block Kit UI components
        response_type: The type of message (either 'in_channel' or 'ephemeral')
        replace_original: True if you use this option for response_url requests
        delete_original: True if you use this option for response_url requests
        unfurl_links: Option to indicate whether text url should unfurl
        unfurl_media: Option to indicate whether media url should unfurl
        metadata: Metadata attached to the message
        headers: Request headers to append only for this request

    Returns:
        Webhook response
    """
    return self.send_dict(
        # It's fine to have None value elements here
        # because _build_body() filters them out when constructing the actual body data
        body={
            "text": text,
            "attachments": attachments,
            "blocks": blocks,
            "response_type": response_type,
            "replace_original": replace_original,
            "delete_original": delete_original,
            "unfurl_links": unfurl_links,
            "unfurl_media": unfurl_media,
            "metadata": metadata,
        },
        headers=headers,
    )

def send_dict(self, body: Dict[str, Any], headers: Optional[Dict[str, str]] = None) ‑> WebhookResponse

Performs a Slack API request and returns the result.

Args

body

JSON data structure (it's still a dict at this point), if you give this argument, body_params and files will be skipped

headers

Request headers to append only for this request

Returns

Webhook response

Expand source code

def send_dict(self, body: Dict[str, Any], headers: Optional[Dict[str, str]] = None) -> WebhookResponse:
    """Performs a Slack API request and returns the result.

    Args:
        body: JSON data structure (it's still a dict at this point),
            if you give this argument, body_params and files will be skipped
        headers: Request headers to append only for this request
    Returns:
        Webhook response
    """
    return self._perform_http_request(
        body=_build_body(body),
        headers=_build_request_headers(self.default_headers, headers),
    )