### Install Task Runner

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/task.md

Installs the Task runner using Homebrew. Other installation methods are available.

```bash
brew install go-task
```

--------------------------------

### Start FastAPI App with Uvicorn

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/examples/default-metrics-diff-labels/README.md

Use Uvicorn to start the FastAPI application. Ensure you have installed dependencies and activated your virtual environment.

```python
uvicorn main:app
```

--------------------------------

### Instrument and Expose App with Defaults

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Instrument your FastAPI app with default metrics and expose them. This is the quickest way to get started.

```python
Instrumentator().instrument(app).expose(app)
```

--------------------------------

### Install Git Hooks with Pre-Commit

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/pre-commit.md

Install pre-commit hooks for all commit types. This command should be run after cloning the repository.

```bash
pre-commit install --install-hooks
```

```bash
pre-commit install --install-hooks --hook-type commit-msg
```

--------------------------------

### Install Pre-commit Hooks

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/DEVELOPMENT.md

Set up pre-commit hooks for the project. This ensures code quality and consistency before commits. Run 'pre-commit run -a' to execute all hooks.

```sh
pre-commit install --install-hooks
```

```sh
pre-commit install --install-hooks --hook-type commit-msg
```

```sh
pre-commit run -a
```

--------------------------------

### Install Python Dependencies with Poetry

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/DEVELOPMENT.md

Use this command after cloning the repository to install project dependencies managed by Poetry. Refer to devel/poetry.md for more details.

```sh
poetry install
```

--------------------------------

### Example Prometheus Metrics Output

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/examples/prom-multi-proc-gunicorn/README.md

This is an example of the metrics output you might see. Note the absence of certain metrics like 'created_by' and system-level metrics (CPU, memory) which are not supported in multi-process mode.

```txt
# TYPE ping_total counter
ping_total 5.0
# HELP metrics_total Number of metrics calls.
# TYPE metrics_total counter
metrics_total 1.0
# HELP main_total Counts of main executions.
# TYPE main_total counter
main_total 2.0
```

--------------------------------

### Example Metric with Namespace and Subsystem

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Illustrates how metrics appear in Prometheus when a namespace and subsystem are specified.

```sh
# TYPE myproject_myservice_http_request_duration_highr_seconds histogram
myproject_myservice_http_request_duration_highr_seconds_bucket{le="0.01"} 0.0
```

--------------------------------

### Add Poetry Plugin

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/poetry.md

Installs a Poetry plugin, such as 'poetry-plugin-up', which can automate dependency updates.

```bash
poetry self add poetry-plugin-up
```

--------------------------------

### Start Gunicorn with Uvicorn Workers

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/examples/prom-multi-proc-gunicorn/README.md

Start the FastAPI application using Gunicorn with two Uvicorn workers. Ensure the Prometheus multi-process directory is clean and created before starting.

```shell
rm -rf "$PROMETHEUS_MULTIPROC_DIR"
mkdir -p "$PROMETHEUS_MULTIPROC_DIR"
gunicorn main:app \
  --config gunicorn.conf.py \
  --workers 2 \
  --worker-class uvicorn.workers.UvicornWorker \
  --bind 0.0.0.0:8080
```

--------------------------------

### Run Project Tests with Task

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/DEVELOPMENT.md

Execute all project tests using the Task runner to verify the setup. Consult devel/task.md for further information on Task usage.

```sh
task test
```

--------------------------------

### Update Poetry

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/poetry.md

Updates the Poetry installation itself to the latest version.

```bash
poetry self update
```

--------------------------------

### Set Prometheus Multi-process Directory

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/examples/prom-multi-proc-gunicorn/README.md

Set the environment variable PROMETHEUS_MULTIPROC_DIR to an unused location before starting Gunicorn. This is required for the Prometheus client library to manage metrics across multiple processes.

```shell
export PROMETHEUS_MULTIPROC_DIR=/tmp/python-testing-pfi/560223ba-887f-429a-9c48-933df56a68ba
```

--------------------------------

### Instrument and Expose App on Startup

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

An alternative method to instrument and expose metrics, particularly useful if app modifications are needed during startup. The metrics are exposed during the application's startup event.

```python
instrumentator = Instrumentator().instrument(app)

@app.on_event("startup")
async def _startup():
    instrumentator.expose(app)
```

--------------------------------

### Monitor Release Workflow

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Open the release workflow in the web interface to monitor its progress. This workflow handles building and publishing the package.

```shell
gh workflow view release --web
```

--------------------------------

### Run Pre-Commit Against All Files

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/pre-commit.md

Execute all configured pre-commit hooks against every file in the repository. Useful for a full code quality check.

```bash
pre-commit run -a
```

--------------------------------

### List Available Tasks

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/task.md

Lists all available tasks defined in the Taskfile.yaml.

```bash
task --list
```

--------------------------------

### Prepare Release Commit

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Stage all relevant files for the release, including the changelog, version updates, and configuration files. Commit the changes with a signed commit message.

```shell
git add CHANGELOG.md src/*/__init__.py pyproject.toml
```

```shell
git commit -S -m "chore: Prepare release v$VERSION"
```

```shell
git log --show-signature -1
```

--------------------------------

### Run Specific Hook Against All Files

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/pre-commit.md

Execute a particular pre-commit hook against all files in the repository. Replace `<hook>` with the desired hook's identifier.

```bash
pre-commit run -a <hook>
```

--------------------------------

### Run a Specific Task

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/task.md

Executes a specified task. Replace '<task>' with the name of the task to run.

```bash
task <task>
```

--------------------------------

### Bump Version with Poetry

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Use Poetry to formally bump the package version. This command updates relevant files like pyproject.toml.

```shell
poetry version $VERSION
```

--------------------------------

### Interact with FastAPI App and Fetch Metrics

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/examples/prom-multi-proc-gunicorn/README.md

Send requests to the /ping endpoint multiple times and then fetch the metrics from the /metrics endpoint. This helps in observing the collected metrics.

```shell
for i in {1..5}; do curl localhost:8080/ping; done
curl localhost:8080/metrics
```

--------------------------------

### Activate Poetry Environment

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/poetry.md

Activates the virtual environment created by Poetry, allowing you to run commands within it directly.

```bash
poetry shell
```

--------------------------------

### Create Instrumentator Instance

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Instantiate the Instrumentator with advanced configuration options like grouping status codes, ignoring untemplated routes, and respecting environment variables for instrumentation.

```python
from prometheus_fastapi_instrumentator import Instrumentator, metrics

instrumentator = Instrumentator(
    should_group_status_codes=False,
    should_ignore_untemplated=True,
    should_respect_env_var=True,
    should_instrument_requests_inprogress=True,
    excluded_handlers=[ ".*admin.*", "/metrics"],
    env_var_name="ENABLE_METRICS",
    inprogress_name="inprogress",
    inprogress_labels=True
)
```

--------------------------------

### Add Request and Response Size Metrics

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Configures and adds metrics for tracking request and response sizes, with options to include handler, method, and status, along with custom namespaces, subsystems, and labels.

```python
instrumentator.add(
    metrics.request_size(
        should_include_handler=True,
        should_include_method=False,
        should_include_status=True,
        metric_namespace="a",
        metric_subsystem="b",
        custom_labels={"service": "example-label"}
    )
).add(
    metrics.response_size(
        should_include_handler=True,
        should_include_method=False,
        should_include_status=True,
        metric_namespace="namespace",
        metric_subsystem="subsystem",
        custom_labels={"service": "example-label"}
    )
)
```

--------------------------------

### Expose Metrics Endpoint with Gzip Compression

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Serve metrics on a FastAPI endpoint. The `expose` method adds an endpoint, and `should_gzip=True` enables compression for efficient data transfer.

```python
instrumentator.expose(app, include_in_schema=False, should_gzip=True)
```

--------------------------------

### Perform Basic Instrumentation

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Register the instrumentation with the FastAPI application. This method should be called after constructing the instrumentator object.

```python
instrumentator.instrument(app)
```

--------------------------------

### Set Release Version

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Set the desired version number for the release. This follows Semantic Versioning.

```shell
VERSION=1.0.1
```

--------------------------------

### Run Commands within Poetry Environment

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/poetry.md

Executes a command within the context of the Poetry-managed virtual environment without explicitly activating it.

```bash
poetry run <command>
```

--------------------------------

### Specify Namespace and Subsystem

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Set the namespace and subsystem for metrics during instrumentation. This helps organize metrics, especially in larger projects.

```python
Instrumentator().instrument(
    app,
    metric_namespace="myproject",
    metric_subsystem="myservice",
).expose(app)
```

```python
Instrumentator().add(
    metrics.default(
        metric_namespace="myproject",
        metric_subsystem="myservice",
    ),
).instrument(app).expose(app)
```

--------------------------------

### Update Project Dependencies

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/poetry.md

Uses the 'poetry-plugin-up' to automatically update project dependencies and bump versions in pyproject.toml.

```bash
poetry up
```

--------------------------------

### Push Changes to Master

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Push the prepared release commit to the master branch. This action may trigger CI/CD pipelines.

```shell
git push origin master
```

--------------------------------

### Tag Latest Commit

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Create an annotated and signed tag for the latest commit. This tag will be used for the release.

```shell
git tag -s v$VERSION -m ""
```

```shell
git show v$VERSION
```

--------------------------------

### Interact with the App and Metrics Endpoint

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/examples/metrics-diff-port-uvicorn/README.md

Shell commands to interact with the running FastAPI application and to fetch metrics from the separate Prometheus endpoint.

```shell
curl localhost:8000/ping
```

```shell
curl localhost:9000/metrics
```

--------------------------------

### Push Release Tag

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Push the newly created tag to the remote repository. This action typically triggers the release workflow.

```shell
git push origin v$VERSION
```

--------------------------------

### Update Version in __init__.py

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Update the __version__ variable in the package's __init__.py file to the new release version. This command uses sed to find and replace the line containing __version__.

```shell
sed -i "/^__version__/c\__version__ = \"$VERSION\"" src/*/__init__.py
```

```shell
grep -n -H __version__ src/*/__init__.py
```

--------------------------------

### Import Instrumentator Class

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Import the Instrumentator class from the library. This is the first step to instrumenting your FastAPI application.

```python
from prometheus_fastapi_instrumentator import Instrumentator
```

--------------------------------

### Interact with the FastAPI App

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/examples/default-metrics-diff-labels/README.md

Use curl to interact with the running FastAPI application. Access the '/ping' endpoint for a basic check and '/metrics' to view Prometheus metrics.

```shell
curl localhost:8000/ping
```

```shell
curl localhost:8000/metrics
```

--------------------------------

### View Git Log Graph

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/RELEASE.md

Display a graphical representation of the recent commit history to ensure the tree structure is as expected.

```shell
git log --graph --oneline --all -n 5
```

--------------------------------

### Update Pre-Commit Hooks

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/devel/pre-commit.md

Automatically update all pre-commit hooks to their latest versions. Run this command periodically to ensure hooks are up-to-date.

```bash
pre-commit autoupdate
```

--------------------------------

### Create Custom HTTP Requested Languages Metric

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Defines and returns a custom instrumentation function to count the occurrences of requested languages based on the 'Accept-Language' header. This function requires careful handling of the request and response objects within the 'Info' object.

```python
from typing import Callable
from prometheus_fastapi_instrumentator.metrics import Info
from prometheus_client import Counter

def http_requested_languages_total() -> Callable[[Info], None]:
    METRIC = Counter(
        "http_requested_languages_total",
        "Number of times a certain language has been requested.",
        labelnames=("langs",)
    )

    def instrumentation(info: Info) -> None:
        langs = set()
        lang_str = info.request.headers["Accept-Language"]
        for element in lang_str.split(","):
            element = element.split(";")[0].strip().lower()
            langs.add(element)
        for language in langs:
            METRIC.labels(language).inc()

    return instrumentation
```

--------------------------------

### Add Latency Metric with Custom Buckets

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Adds the default latency metric to the instrumentator, allowing for custom bucket configurations.

```python
instrumentator.add(metrics.latency(buckets=(1, 2, 3,)))
```

--------------------------------

### Specify Static Custom Labels

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Add static custom labels to metrics by passing them to the metrics closure. Useful for filtering or categorizing metrics.

```python
Instrumentator().add(
    metrics.default(
        custom_labels={"environment": "dev"},
    ),
).instrument(app).expose(app)
```

--------------------------------

### Add Custom Metric to Instrumentator

Source: https://github.com/trallnag/prometheus-fastapi-instrumentator/blob/master/README.md

Registers a custom instrumentation function, such as the http_requested_languages_total metric, with the instrumentator instance.

```python
instrumentator.add(http_requested_languages_total())
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.