# Source code for opentelemetry.exporter.otlp.proto.http.trace_exporter

    # Copyright The OpenTelemetry Authors
    #
    # 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
    #
    #     http://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.

    import gzip
    import logging
    import random
    import threading
    import zlib
    from io import BytesIO
    from os import environ
    from time import time
    from typing import Dict, Optional, Sequence

    import requests
    from requests.exceptions import ConnectionError

    from opentelemetry.exporter.otlp.proto.common.trace_encoder import (
        encode_spans,
    )
    from opentelemetry.exporter.otlp.proto.http import (
        _OTLP_HTTP_HEADERS,
        Compression,
    )
    from opentelemetry.exporter.otlp.proto.http._common import (
        _is_retryable,
        _load_session_from_envvar,
    )
    from opentelemetry.sdk.environment_variables import (
        _OTEL_PYTHON_EXPORTER_OTLP_HTTP_TRACES_CREDENTIAL_PROVIDER,
        OTEL_EXPORTER_OTLP_CERTIFICATE,
        OTEL_EXPORTER_OTLP_CLIENT_CERTIFICATE,
        OTEL_EXPORTER_OTLP_CLIENT_KEY,
        OTEL_EXPORTER_OTLP_COMPRESSION,
        OTEL_EXPORTER_OTLP_ENDPOINT,
        OTEL_EXPORTER_OTLP_HEADERS,
        OTEL_EXPORTER_OTLP_TIMEOUT,
        OTEL_EXPORTER_OTLP_TRACES_CERTIFICATE,
        OTEL_EXPORTER_OTLP_TRACES_CLIENT_CERTIFICATE,
        OTEL_EXPORTER_OTLP_TRACES_CLIENT_KEY,
        OTEL_EXPORTER_OTLP_TRACES_COMPRESSION,
        OTEL_EXPORTER_OTLP_TRACES_ENDPOINT,
        OTEL_EXPORTER_OTLP_TRACES_HEADERS,
        OTEL_EXPORTER_OTLP_TRACES_TIMEOUT,
    )
    from opentelemetry.sdk.trace import ReadableSpan
    from opentelemetry.sdk.trace.export import SpanExporter, SpanExportResult
    from opentelemetry.util.re import parse_env_headers

    _logger = logging.getLogger(__name__)

    DEFAULT_COMPRESSION = Compression.NoCompression
    DEFAULT_ENDPOINT = "http://localhost:4318/"
    DEFAULT_TRACES_EXPORT_PATH = "v1/traces"
    DEFAULT_TIMEOUT = 10  # in seconds
    _MAX_RETRYS = 6

    class OTLPSpanExporter(SpanExporter):
        def __init__(
            self,
            endpoint: Optional[str] = None,
            certificate_file: Optional[str] = None,
            client_key_file: Optional[str] = None,
            client_certificate_file: Optional[str] = None,
            headers: Optional[Dict[str, str]] = None,
            timeout: Optional[float] = None,
            compression: Optional[Compression] = None,
            session: Optional[requests.Session] = None,
        ):
            self._shutdown_in_progress = threading.Event()
            self._endpoint = endpoint or environ.get(
                OTEL_EXPORTER_OTLP_TRACES_ENDPOINT,
                _append_trace_path(
                    environ.get(OTEL_EXPORTER_OTLP_ENDPOINT, DEFAULT_ENDPOINT)
                ),
            )
            self._certificate_file = certificate_file or environ.get(
                OTEL_EXPORTER_OTLP_TRACES_CERTIFICATE,
                environ.get(OTEL_EXPORTER_OTLP_CERTIFICATE, True),
            )
            self._client_key_file = client_key_file or environ.get(
                OTEL_EXPORTER_OTLP_TRACES_CLIENT_KEY,
                environ.get(OTEL_EXPORTER_OTLP_CLIENT_KEY, None),
            )
            self._client_certificate_file = client_certificate_file or environ.get(
                OTEL_EXPORTER_OTLP_TRACES_CLIENT_CERTIFICATE,
                environ.get(OTEL_EXPORTER_OTLP_CLIENT_CERTIFICATE, None),
            )
            self._client_cert = (
                (self._client_certificate_file, self._client_key_file)
                if self._client_certificate_file and self._client_key_file
                else self._client_certificate_file
            )
            headers_string = environ.get(
                OTEL_EXPORTER_OTLP_TRACES_HEADERS,
                environ.get(OTEL_EXPORTER_OTLP_HEADERS, ""),
            )
            self._headers = headers or parse_env_headers(
                headers_string, liberal=True
            )
            self._timeout = timeout or float(
                environ.get(
                    OTEL_EXPORTER_OTLP_TRACES_TIMEOUT,
                    environ.get(OTEL_EXPORTER_OTLP_TIMEOUT, DEFAULT_TIMEOUT),
                )
            )
            self._compression = compression or _compression_from_env()
            self._session = (
                session
                or _load_session_from_envvar(
                    _OTEL_PYTHON_EXPORTER_OTLP_HTTP_TRACES_CREDENTIAL_PROVIDER
                )
                or requests.Session()
            )
            self._session.headers.update(self._headers)
            self._session.headers.update(_OTLP_HTTP_HEADERS)
            # let users override our defaults
            self._session.headers.update(self._headers)
            if self._compression is not Compression.NoCompression:
                self._session.headers.update(
                    {"Content-Encoding": self._compression.value}
                )
            self._shutdown = False

        def _export(
            self, serialized_data: bytes, timeout_sec: Optional[float] = None
        ):
            data = serialized_data
            if self._compression == Compression.Gzip:
                gzip_data = BytesIO()
                with gzip.GzipFile(fileobj=gzip_data, mode="w") as gzip_stream:
                    gzip_stream.write(serialized_data)
                data = gzip_data.getvalue()
            elif self._compression == Compression.Deflate:
                data = zlib.compress(serialized_data)

            if timeout_sec is None:
                timeout_sec = self._timeout

            # By default, keep-alive is enabled in Session's request
            # headers. Backends may choose to close the connection
            # while a post happens which causes an unhandled
            # exception. This try/except will retry the post on such exceptions
            try:
                resp = self._session.post(
                    url=self._endpoint,
                    data=data,
                    verify=self._certificate_file,
                    timeout=timeout_sec,
                    cert=self._client_cert,
                )
            except ConnectionError:
                resp = self._session.post(
                    url=self._endpoint,
                    data=data,
                    verify=self._certificate_file,
                    timeout=timeout_sec,
                    cert=self._client_cert,
                )
            return resp

        def export(self, spans: Sequence[ReadableSpan]) -> SpanExportResult:
            if self._shutdown:
                _logger.warning("Exporter already shutdown, ignoring batch")
                return SpanExportResult.FAILURE

            serialized_data = encode_spans(spans).SerializePartialToString()
            deadline_sec = time() + self._timeout
            for retry_num in range(_MAX_RETRYS):
                resp = self._export(serialized_data, deadline_sec - time())
                if resp.ok:
                    return SpanExportResult.SUCCESS
                # multiplying by a random number between .8 and 1.2 introduces a +/20% jitter to each backoff.
                backoff_seconds = 2**retry_num * random.uniform(0.8, 1.2)
                if (
                    not _is_retryable(resp)
                    or retry_num + 1 == _MAX_RETRYS
                    or backoff_seconds > (deadline_sec - time())
                    or self._shutdown
                ):
                    _logger.error(
                        "Failed to export span batch code: %s, reason: %s",
                        resp.status_code,
                        resp.text,
                    )
                    return SpanExportResult.FAILURE
                _logger.warning(
                    "Transient error %s encountered while exporting span batch, retrying in %.2fs.",
                    resp.reason,
                    backoff_seconds,
                )
                shutdown = self._shutdown_in_progress.wait(backoff_seconds)
                if shutdown:
                    _logger.warning("Shutdown in progress, aborting retry.")
                    break
            return SpanExportResult.FAILURE

        def shutdown(self):
            if self._shutdown:
                _logger.warning("Exporter already shutdown, ignoring call")
                return
            self._shutdown = True
            self._shutdown_in_progress.set()
            self._session.close()

        def force_flush(self, timeout_millis: int = 30000) -> bool:
            """Nothing is buffered in this exporter, so this method does nothing."""
            return True

    def _compression_from_env() -> Compression:
        compression = (
            environ.get(
                OTEL_EXPORTER_OTLP_TRACES_COMPRESSION,
                environ.get(OTEL_EXPORTER_OTLP_COMPRESSION, "none"),
            )
            .lower()
            .strip()
        )
        return Compression(compression)

    def _append_trace_path(endpoint: str) -> str:
        if endpoint.endswith("/"):
            return endpoint + DEFAULT_TRACES_EXPORT_PATH
        return endpoint + f"/{DEFAULT_TRACES_EXPORT_PATH}"