Prometheus Remote Write Exporter (6/6)

.flake8

@@ -4,7 +4,7 @@ ignore =
   F401  # unused import, defer to pylint
   W503  # allow line breaks before binary ops
   W504  # allow line breaks after binary ops
-  E203  # allow whitespace before ':' (https://github.com/psf/black#slices) 
+  E203  # allow whitespace before ':' (https://github.com/psf/black#slices)
 exclude =
   .bzr
   .git

.pylintrc

@@ -7,7 +7,7 @@ extension-pkg-whitelist=
 
 # Add list of files or directories to be excluded. They should be base names, not
 # paths.
-ignore=CVS,gen
+ignore=CVS,gen,Dockerfile,docker-compose.yml,README.md,requirements.txt,cortex-config.yml
 
 # Add files or directories matching the regex patterns to be excluded. The
 # regex matches against base names, not paths.

exporter/opentelemetry-exporter-prometheus-remote-write/README.rst

@@ -1,27 +1,236 @@
-OpenTelemetry Prometheus Remote Write Exporter
-==============================================
+OpenTelemetry Python SDK Prometheus Remote Write Exporter
+=========================================================
 
-This library allows exporting metric data to `Prometheus Remote Write Integrated Backends
-<https://prometheus.io/docs/operating/integrations/>`_. Latest `types.proto
-<https://github.com/prometheus/prometheus/blob/master/prompb/types.proto>` and `remote.proto
-<https://github.com/prometheus/prometheus/blob/master/prompb/remote.proto>` Protocol Buffers
-used to create WriteRequest objects were taken from Prometheus repository. Development is
-currently in progress.
+This package contains an exporter to send `OTLP`_ metrics from the
+Python SDK directly to a Prometheus Remote Write integrated backend
+(such as Cortex or Thanos) without having to run an instance of the
+Prometheus server. The image below shows the two Prometheus exporters in
+the OpenTelemetry Python SDK.
+
+Pipeline 1 illustrates the setup required for a Prometheus "pull"
+exporter.
+
+Pipeline 2 illustrates the setup required for the Prometheus Remote
+Write exporter.
+
+|Prometheus SDK pipelines|
+
+The Prometheus Remote Write Exporter is a "push" based exporter and only
+works with the OpenTelemetry `push controller`_. The controller
+periodically collects data and passes it to the exporter. This exporter
+then converts the data into `timeseries`_ and sends it to the Remote
+Write integrated backend through HTTP POST requests. The metrics
+collection datapath is shown below:
+
+|controller_datapath_final|
+
+See the ``example`` folder for a demo usage of this exporter
+
+Table of Contents
+=================
+
+-  `Summary`_
+-  `Table of Contents`_
+
+   -  `Installation`_
+   -  `Quickstart`_
+   -  `Configuring the Exporter`_
+   -  `Securing the Exporter`_
+
+      -  `Authentication`_
+      -  `TLS`_
+
+   -  `Supported Aggregators`_
+   -  `Error Handling`_
+   -  `Retry Logic`_
+   -  `Contributing`_
+
+      -  `Design Doc`_
 
 Installation
 ------------
+-  To install from the latest PyPi release, run
+   ``pip install opentelemetry-exporter-prometheus-remote-write``
+-  To install from the local repository, run
+   ``pip install -e exporter/opentelemetry-exporter-prometheus-remote-write/``
+   in the project root
+
+Quickstart
+----------
+
+.. code:: python
+
+   from opentelemetry import metrics
+   from opentelemetry.sdk.metrics import MeterProvider
+   from opentelemetry.exporter.prometheus_remote_write import (
+       PrometheusRemoteWriteMetricsExporter
+   )
+
+   # Sets the global MeterProvider instance
+   metrics.set_meter_provider(MeterProvider())
+
+   # The Meter is responsible for creating and recording metrics. Each meter has a unique name, which we set as the module's name here.
+   meter = metrics.get_meter(__name__)
+
+   exporter = PrometheusRemoteWriteMetricsExporter(endpoint="endpoint_here") # add other params as needed
+
+   metrics.get_meter_provider().start_pipeline(meter, exporter, 5)
+
+Configuring the Exporter
+------------------------
+
+The exporter can be configured through parameters passed to the
+constructor. Here are all the options:
+
+-  ``endpoint``: url where data will be sent **(Required)**
+-  ``basic_auth``: username and password for authentication
+   **(Optional)**
+-  ``headers``: additional headers for remote write request as
+   determined by the remote write backend's API **(Optional)**
+-  ``timeout``: timeout for requests to the remote write endpoint in
+   seconds **(Optional)**
+-  ``proxies``: dict mapping request proxy protocols to proxy urls
+   **(Optional)**
+-  ``tls_config``: configuration for remote write TLS settings
+   **(Optional)**
+
+Example with all the configuration options:
+
+.. code:: python
+
+   exporter = PrometheusRemoteWriteMetricsExporter(
+       endpoint="http://localhost:9009/api/prom/push",
+       timeout=30,
+       basic_auth={
+           "username": "user",
+           "password": "pass123",
+       },
+       headers={
+           "X-Scope-Org-ID": "5",
+           "Authorization": "Bearer mytoken123",
+       },
+       proxies={
+           "http": "http://10.10.1.10:3000",
+           "https": "http://10.10.1.10:1080",
+       },
+       tls_config={
+           "cert_file": "path/to/file",
+           "key_file": "path/to/file",
+           "ca_file": "path_to_file",
+           "insecure_skip_verify": true, # for developing purposes
+       }
+   )
+
+Securing the Exporter
+---------------------
+
+Authentication
+~~~~~~~~~~~~~~
+
+The exporter provides two forms of authentication which are shown below.
+Users can add their own custom authentication by setting the appropriate
+values in the ``headers`` dictionary
+
+1. Basic Authentication Basic authentication sets a HTTP Authorization
+   header containing a base64 encoded username/password pair. See `RFC
+   7617`_ for more information. This
+
+.. code:: python
+
+   exporter = PrometheusRemoteWriteMetricsExporter(
+       basic_auth={"username": "base64user",  "password": "base64pass"}
+   )
+
+2. Bearer Token Authentication This custom configuration can be achieved
+   by passing in a custom ``header`` to the constructor. See `RFC 6750`_
+   for more information.
+
+.. code:: python
+
+   header = {
+       "Authorization": "Bearer mytoken123"
+   }
+
+TLS
+~~~
+
+Users can add TLS to the exporter's HTTP Client by providing certificate
+and key files in the ``tls_config`` parameter.
+
+Supported Aggregators
+---------------------
+
+-  Sum
+-  MinMaxSumCount
+-  Histogram
+-  LastValue
+-  ValueObserver
+
+Error Handling
+--------------
+
+In general, errors are raised by the calling function. The exception is
+for failed requests where any error status code is logged as a warning
+instead.
+
+This is because the exporter does not implement any retry logic as it
+sends cumulative metrics data. This means that data will be preserved
+even if some exports fail.
+
+For example, consider a situation where a user increments a Counter
+instrument 5 times and an export happens between each increment. If the
+exports happen like so:
 
 ::
 
-    pip install opentelemetry-exporter-prometheus-remote-write
+   SUCCESS FAIL FAIL SUCCESS SUCCESS
+   1       2    3    4       5
 
+Then the recieved data will be:
 
-.. _Prometheus: https://prometheus.io/
-.. _OpenTelemetry: https://github.com/open-telemetry/opentelemetry-python/
+::
 
+   1 4 5
 
-References
-----------
+The end result is the same since the aggregations are cumulative
+Contributing
+------------
+
+This exporter's datapath is as follows:
+
+|Exporter datapath| *Entites with ``*`` after their name are not actual
+classes but rather logical groupings of functions within the exporter.*
+
+If you would like to learn more about the exporter's structure and
+design decisions please view the design document below
+
+Design Doc
+~~~~~~~~~~
+
+`Design Document`_
+
+This document is stored elsewhere as it contains large images which will
+significantly increase the size of this repo.
 
-* `Prometheus <https://prometheus.io/>`_
-* `OpenTelemetry Project <https://opentelemetry.io/>`_
+.. _Design Document: https://github.com/open-o11y/docs/tree/master/python-prometheus-remote-write
+.. |Exporter datapath| image:: https://user-images.githubusercontent.com/20804975/100285717-604c7280-2f3f-11eb-9b73-bdf70afce9dd.png
+.. _OTLP: https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/protocol/otlp.md
+.. _push controller: https://github.com/open-telemetry/opentelemetry-python/blob/master/opentelemetry-sdk/src/opentelemetry/sdk/metrics/export/controller.py
+.. _`timeseries`: https://prometheus.io/docs/concepts/data_model/
+.. _Summary: #opentelemetry-python-sdk-prometheus-remote-write-exporter
+.. _Table of Contents: #table-of-contents
+.. _Installation: #installation
+.. _Quickstart: #quickstart
+.. _Configuring the Exporter: #configuring-the-exporter
+.. _Securing the Exporter: #securing-the-exporter
+.. _Authentication: #authentication
+.. _TLS: #tls
+.. _Supported Aggregators: #supported-aggregators
+.. _Error Handling: #error-handling
+.. _Retry Logic: #retry-logic
+.. _Contributing: #contributing
+.. _Design Doc: #design-doc
+.. |Prometheus SDK pipelines| image:: https://user-images.githubusercontent.com/20804975/100285430-e320fd80-2f3e-11eb-8217-a562c559153c.png
+.. |controller_datapath_final| image:: https://user-images.githubusercontent.com/20804975/100486582-79d1f380-30d2-11eb-8d17-d3e58e5c34e9.png
+.. _RFC 7617: https://tools.ietf.org/html/rfc7617
+.. _RFC 6750: https://tools.ietf.org/html/rfc6750

exporter/opentelemetry-exporter-prometheus-remote-write/examples/Dockerfile

@@ -0,0 +1,8 @@
+FROM python:3.7
+WORKDIR /code
+
+COPY . .
+RUN apt-get update -y && apt-get install libsnappy-dev -y
+RUN pip install -e .
+RUN pip install -r ./examples/requirements.txt
+CMD ["python", "./examples/sampleapp.py"]

exporter/opentelemetry-exporter-prometheus-remote-write/examples/README.md

@@ -0,0 +1,42 @@
+# Prometheus Remote Write Exporter Example
+This example uses [Docker Compose](https://docs.docker.com/compose/) to set up:
+
+1. A Python program that creates 5 instruments with 5 unique
+aggregators and a randomized load generator
+2. An instance of [Cortex](https://cortexmetrics.io/) to recieve the metrics
+data
+3. An instance of [Grafana](https://grafana.com/) to visualizse the exported
+data
+
+## Requirements
+* Have Docker Compose [installed](https://docs.docker.com/compose/install/)
+
+*Users do not need to install Python as the app will be run in the Docker Container*
+
+## Instructions
+1. Run `docker-compose up -d` in the the `examples/` directory
+
+The `-d` flag causes all services to run in detached mode and frees up your
+terminal session. This also causes no logs to show up. Users can attach themselves to the service's logs manually using `docker logs ${CONTAINER_ID} --follow`
+
+2. Log into the Grafana instance at [http://localhost:3000](http://localhost:3000)
+   * login credentials are `username: admin` and `password: admin`
+   * There may be an additional screen on setting a new password. This can be skipped and is optional
+
+3. Navigate to the `Data Sources` page
+   * Look for a gear icon on the left sidebar and select `Data Sources`
+
+4. Add a new Prometheus Data Source
+   * Use `http://cortex:9009/api/prom` as the URL
+   * (OPTIONAl) set the scrape interval to `2s` to make updates appear quickly
+   * click `Save & Test`
+
+5. Go to `Metrics Explore` to query metrics
+   * Look for a compass icon on the left sidebar
+   * click `Metrics` for a dropdown list of all the available metrics
+   * (OPTIONAL) Adjust time range by clicking the `Last 6 hours` button on the upper right side of the graph
+   * (OPTIONAL) Set up auto-refresh by selecting an option under the dropdown next to the refresh button on the upper right side of the graph
+   * Click the refresh button and data should show up on hte graph
+
+6. Shutdown the services when finished
+   * Run `docker-compose down` in the examples directory