Logging Flask requests with structure and colors

03114

Logging is one of those things on which all developers agree, what we don’t agree with is the format.

You can log using “free text”, agree on a structure of use full JSON.

I tend to use a combination of free text and structured logging. My favorite logging library so far is lograge for Rails which funnily enough is described by the authors as "An attempt to tame Rails' default policy to log everything".

Flask definitely doesn’t get logging right by default and I think it has to do also with how complicated Python’s default logging which honestly I never completely understood.

Anyway, back on the scope of the article. Lograge is pretty neat because it turns this:

Started GET "/" for 127.0.0.1 at 2012-03-10 14:28:14 +0100
Processing by HomeController#index as HTML
  Rendered text template within layouts/application (0.0ms)
  Rendered layouts/_assets.html.erb (2.0ms)
  Rendered layouts/_top.html.erb (2.6ms)
  Rendered layouts/_about.html.erb (0.3ms)
  Rendered layouts/_google_analytics.html.erb (0.4ms)
Completed 200 OK in 79ms (Views: 78.8ms | ActiveRecord: 0.0ms)
Started GET "/" for 127.0.0.1 at 2012-03-10 14:28:14 +0100
Processing by HomeController#index as HTML
  Rendered text template within layouts/application (0.0ms)
  Rendered layouts/_assets.html.erb (2.0ms)
  Rendered layouts/_top.html.erb (2.6ms)
  Rendered layouts/_about.html.erb (0.3ms)
  Rendered layouts/_google_analytics.html.erb (0.4ms)
Completed 200 OK in 79ms (Views: 78.8ms | ActiveRecord: 0.0ms)


Started GET "/" for 127.0.0.1 at 2012-03-10 14:28:14 +0100
Processing by HomeController#index as HTML
  Rendered text template within layouts/application (0.0ms)
  Rendered layouts/_assets.html.erb (2.0ms)
  Rendered layouts/_top.html.erb (2.6ms)
  Rendered layouts/_about.html.erb (0.3ms)
  Rendered layouts/_google_analytics.html.erb (0.4ms)
Completed 200 OK in 79ms (Views: 78.8ms | ActiveRecord: 0.0ms)

Enter fullscreen mode Exit fullscreen mode

into this:

method=GET path=/jobs/833552.json format=json controller=JobsController  action=show status=200 duration=58.33 view=40.43 db=15.26
method=GET path=/jobs/833552.json format=json controller=JobsController  action=show status=200 duration=58.33 view=40.43 db=15.26


method=GET path=/jobs/833552.json format=json controller=JobsController  action=show status=200 duration=58.33 view=40.43 db=15.26

Enter fullscreen mode Exit fullscreen mode

I wanted to replicate that with the latest released version of Flask (v0.12.2) and add some coloring to get to this:

Info to collect

As you can see from the image we need:

  • request method
  • request path
  • response status code
  • request time
  • time stamp in RFC339 format
  • request ip
  • request host
  • request params

How to collect it in Flask

Flask has hooks to inject your code at different stages of requests. A bit like Rails request filters.

We’re going to use before_request and after_request.

The first thing we’re going to collect it the timestamp of the beginning of the request:

<span>@app.before_request</span>
<span>def</span> <span>start_timer</span><span>():</span>
    <span>g</span><span>.</span><span>start</span> <span>=</span> <span>time</span><span>.</span><span>time</span><span>()</span>
<span>@app.before_request</span>
<span>def</span> <span>start_timer</span><span>():</span>
    <span>g</span><span>.</span><span>start</span> <span>=</span> <span>time</span><span>.</span><span>time</span><span>()</span>


@app.before_request
def start_timer():
    g.start = time.time()

Enter fullscreen mode Exit fullscreen mode

app is the Flask app, g is the flask global object and time.time() well… you know 🙂

The rest of the information can be collected after the request is finished with:

<span>@app.after_request</span>
<span>def</span> <span>log_request</span><span>(</span><span>response</span><span>):</span>
    <span>if</span> <span>request</span><span>.</span><span>path</span> <span>==</span> <span>'</span><span>/favicon.ico</span><span>'</span><span>:</span>
        <span>return</span> <span>response</span>
    <span>elif</span> <span>request</span><span>.</span><span>path</span><span>.</span><span>startswith</span><span>(</span><span>'</span><span>/static</span><span>'</span><span>):</span>
        <span>return</span> <span>response</span>
    <span>now</span> <span>=</span> <span>time</span><span>.</span><span>time</span><span>()</span>
    <span>duration</span> <span>=</span> <span>round</span><span>(</span><span>now</span> <span>-</span> <span>g</span><span>.</span><span>start</span><span>,</span> <span>2</span><span>)</span>
    <span>dt</span> <span>=</span> <span>datetime</span><span>.</span><span>datetime</span><span>.</span><span>fromtimestamp</span><span>(</span><span>now</span><span>)</span>
    <span>timestamp</span> <span>=</span> <span>rfc3339</span><span>(</span><span>dt</span><span>,</span> <span>utc</span><span>=</span><span>True</span><span>)</span>
    <span>ip</span> <span>=</span> <span>request</span><span>.</span><span>headers</span><span>.</span><span>get</span><span>(</span><span>'</span><span>X-Forwarded-For</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>remote_addr</span><span>)</span>
    <span>host</span> <span>=</span> <span>request</span><span>.</span><span>host</span><span>.</span><span>split</span><span>(</span><span>'</span><span>:</span><span>'</span><span>,</span> <span>1</span><span>)[</span><span>0</span><span>]</span>
    <span>args</span> <span>=</span> <span>dict</span><span>(</span><span>request</span><span>.</span><span>args</span><span>)</span>
<span>@app.after_request</span>
<span>def</span> <span>log_request</span><span>(</span><span>response</span><span>):</span>
    <span>if</span> <span>request</span><span>.</span><span>path</span> <span>==</span> <span>'</span><span>/favicon.ico</span><span>'</span><span>:</span>
        <span>return</span> <span>response</span>
    <span>elif</span> <span>request</span><span>.</span><span>path</span><span>.</span><span>startswith</span><span>(</span><span>'</span><span>/static</span><span>'</span><span>):</span>
        <span>return</span> <span>response</span>

    <span>now</span> <span>=</span> <span>time</span><span>.</span><span>time</span><span>()</span>
    <span>duration</span> <span>=</span> <span>round</span><span>(</span><span>now</span> <span>-</span> <span>g</span><span>.</span><span>start</span><span>,</span> <span>2</span><span>)</span>
    <span>dt</span> <span>=</span> <span>datetime</span><span>.</span><span>datetime</span><span>.</span><span>fromtimestamp</span><span>(</span><span>now</span><span>)</span>
    <span>timestamp</span> <span>=</span> <span>rfc3339</span><span>(</span><span>dt</span><span>,</span> <span>utc</span><span>=</span><span>True</span><span>)</span>

    <span>ip</span> <span>=</span> <span>request</span><span>.</span><span>headers</span><span>.</span><span>get</span><span>(</span><span>'</span><span>X-Forwarded-For</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>remote_addr</span><span>)</span>
    <span>host</span> <span>=</span> <span>request</span><span>.</span><span>host</span><span>.</span><span>split</span><span>(</span><span>'</span><span>:</span><span>'</span><span>,</span> <span>1</span><span>)[</span><span>0</span><span>]</span>
    <span>args</span> <span>=</span> <span>dict</span><span>(</span><span>request</span><span>.</span><span>args</span><span>)</span>


@app.after_request
def log_request(response):
    if request.path == '/favicon.ico':
        return response
    elif request.path.startswith('/static'):
        return response

    now = time.time()
    duration = round(now - g.start, 2)
    dt = datetime.datetime.fromtimestamp(now)
    timestamp = rfc3339(dt, utc=True)

    ip = request.headers.get('X-Forwarded-For', request.remote_addr)
    host = request.host.split(':', 1)[0]
    args = dict(request.args)

Enter fullscreen mode Exit fullscreen mode

  • This does not log the favicon or requests for static files. You might want to keep them
  • The timestamp is in UTC, you might want it in a specific timezone but I tend to like logs in UTC. I use rfc3339 library
  • It retrieves the IP address from X-Forwarded-For to give precedence to proxied requests, defaults to Flask’s remote address
  • Host is retrieved without the optional port

The next step is to create the params and add coloring:

    <span>log_params</span> <span>=</span> <span>[</span>
        <span>(</span><span>'</span><span>method</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>method</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>path</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>path</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>status</span><span>'</span><span>,</span> <span>response</span><span>.</span><span>status_code</span><span>,</span> <span>'</span><span>yellow</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>duration</span><span>'</span><span>,</span> <span>duration</span><span>,</span> <span>'</span><span>green</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>time</span><span>'</span><span>,</span> <span>timestamp</span><span>,</span> <span>'</span><span>magenta</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>ip</span><span>'</span><span>,</span> <span>ip</span><span>,</span> <span>'</span><span>red</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>host</span><span>'</span><span>,</span> <span>host</span><span>,</span> <span>'</span><span>red</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>params</span><span>'</span><span>,</span> <span>args</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>)</span>
    <span>]</span>
    <span>request_id</span> <span>=</span> <span>request</span><span>.</span><span>headers</span><span>.</span><span>get</span><span>(</span><span>'</span><span>X-Request-ID</span><span>'</span><span>)</span>
    <span>if</span> <span>request_id</span><span>:</span>
        <span>log_params</span><span>.</span><span>append</span><span>((</span><span>'</span><span>request_id</span><span>'</span><span>,</span> <span>request_id</span><span>,</span> <span>'</span><span>yellow</span><span>'</span><span>))</span>
    <span>log_params</span> <span>=</span> <span>[</span>
        <span>(</span><span>'</span><span>method</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>method</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>path</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>path</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>status</span><span>'</span><span>,</span> <span>response</span><span>.</span><span>status_code</span><span>,</span> <span>'</span><span>yellow</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>duration</span><span>'</span><span>,</span> <span>duration</span><span>,</span> <span>'</span><span>green</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>time</span><span>'</span><span>,</span> <span>timestamp</span><span>,</span> <span>'</span><span>magenta</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>ip</span><span>'</span><span>,</span> <span>ip</span><span>,</span> <span>'</span><span>red</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>host</span><span>'</span><span>,</span> <span>host</span><span>,</span> <span>'</span><span>red</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>params</span><span>'</span><span>,</span> <span>args</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>)</span>
    <span>]</span>
    <span>request_id</span> <span>=</span> <span>request</span><span>.</span><span>headers</span><span>.</span><span>get</span><span>(</span><span>'</span><span>X-Request-ID</span><span>'</span><span>)</span>
    <span>if</span> <span>request_id</span><span>:</span>
        <span>log_params</span><span>.</span><span>append</span><span>((</span><span>'</span><span>request_id</span><span>'</span><span>,</span> <span>request_id</span><span>,</span> <span>'</span><span>yellow</span><span>'</span><span>))</span>


    log_params = [
        ('method', request.method, 'blue'),
        ('path', request.path, 'blue'),
        ('status', response.status_code, 'yellow'),
        ('duration', duration, 'green'),
        ('time', timestamp, 'magenta'),
        ('ip', ip, 'red'),
        ('host', host, 'red'),
        ('params', args, 'blue')
    ]
    request_id = request.headers.get('X-Request-ID')
    if request_id:
        log_params.append(('request_id', request_id, 'yellow'))

Enter fullscreen mode Exit fullscreen mode

I also optionally log the request id which is set by Heroku.

The last part is actually building the line and outputting it:

    <span>parts</span> <span>=</span> <span>[]</span>  <span># as any dev I hate naming temporary variables :-) </span>    <span>for</span> <span>name</span><span>,</span> <span>value</span><span>,</span> <span>color</span> <span>in</span> <span>log_params</span><span>:</span>
        <span>part</span> <span>=</span> <span>color</span><span>(</span><span>"</span><span>{}={}</span><span>"</span><span>.</span><span>format</span><span>(</span><span>name</span><span>,</span> <span>value</span><span>),</span> <span>fg</span><span>=</span><span>color</span><span>)</span>
        <span>parts</span><span>.</span><span>append</span><span>(</span><span>part</span><span>)</span>
    <span>line</span> <span>=</span> <span>"</span><span> </span><span>"</span><span>.</span><span>join</span><span>(</span><span>parts</span><span>)</span>
    <span>app</span><span>.</span><span>logger</span><span>.</span><span>info</span><span>(</span><span>line</span><span>)</span>
    <span>parts</span> <span>=</span> <span>[]</span>  <span># as any dev I hate naming temporary variables :-) </span>    <span>for</span> <span>name</span><span>,</span> <span>value</span><span>,</span> <span>color</span> <span>in</span> <span>log_params</span><span>:</span>
        <span>part</span> <span>=</span> <span>color</span><span>(</span><span>"</span><span>{}={}</span><span>"</span><span>.</span><span>format</span><span>(</span><span>name</span><span>,</span> <span>value</span><span>),</span> <span>fg</span><span>=</span><span>color</span><span>)</span>
        <span>parts</span><span>.</span><span>append</span><span>(</span><span>part</span><span>)</span>
    <span>line</span> <span>=</span> <span>"</span><span> </span><span>"</span><span>.</span><span>join</span><span>(</span><span>parts</span><span>)</span>

    <span>app</span><span>.</span><span>logger</span><span>.</span><span>info</span><span>(</span><span>line</span><span>)</span>


    parts = []  # as any dev I hate naming temporary variables :-)     for name, value, color in log_params:
        part = color("{}={}".format(name, value), fg=color)
        parts.append(part)
    line = " ".join(parts)

    app.logger.info(line)

Enter fullscreen mode Exit fullscreen mode

color comes from the ansicolors library.

This is the whole snippet:

<span>import</span> <span>datetime</span>
<span>import</span> <span>time</span>
<span>import</span> <span>colors</span>
<span>from</span> <span>flask</span> <span>import</span> <span>g</span><span>,</span> <span>request</span>
<span>from</span> <span>rfc3339</span> <span>import</span> <span>rfc3339</span>
<span>app</span> <span>=</span> <span>create_your_flask_app</span><span>()</span>
<span>@app.before_request</span>
<span>def</span> <span>start_timer</span><span>():</span>
    <span>g</span><span>.</span><span>start</span> <span>=</span> <span>time</span><span>.</span><span>time</span><span>()</span>
<span>@app.after_request</span>
<span>def</span> <span>log_request</span><span>(</span><span>response</span><span>):</span>
    <span>if</span> <span>request</span><span>.</span><span>path</span> <span>==</span> <span>'</span><span>/favicon.ico</span><span>'</span><span>:</span>
        <span>return</span> <span>response</span>
    <span>elif</span> <span>request</span><span>.</span><span>path</span><span>.</span><span>startswith</span><span>(</span><span>'</span><span>/static</span><span>'</span><span>):</span>
        <span>return</span> <span>response</span>
    <span>now</span> <span>=</span> <span>time</span><span>.</span><span>time</span><span>()</span>
    <span>duration</span> <span>=</span> <span>round</span><span>(</span><span>now</span> <span>-</span> <span>g</span><span>.</span><span>start</span><span>,</span> <span>2</span><span>)</span>
    <span>dt</span> <span>=</span> <span>datetime</span><span>.</span><span>datetime</span><span>.</span><span>fromtimestamp</span><span>(</span><span>now</span><span>)</span>
    <span>timestamp</span> <span>=</span> <span>rfc3339</span><span>(</span><span>dt</span><span>,</span> <span>utc</span><span>=</span><span>True</span><span>)</span>
    <span>ip</span> <span>=</span> <span>request</span><span>.</span><span>headers</span><span>.</span><span>get</span><span>(</span><span>'</span><span>X-Forwarded-For</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>remote_addr</span><span>)</span>
    <span>host</span> <span>=</span> <span>request</span><span>.</span><span>host</span><span>.</span><span>split</span><span>(</span><span>'</span><span>:</span><span>'</span><span>,</span> <span>1</span><span>)[</span><span>0</span><span>]</span>
    <span>args</span> <span>=</span> <span>dict</span><span>(</span><span>request</span><span>.</span><span>args</span><span>)</span>
    <span>log_params</span> <span>=</span> <span>[</span>
        <span>(</span><span>'</span><span>method</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>method</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>path</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>path</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>status</span><span>'</span><span>,</span> <span>response</span><span>.</span><span>status_code</span><span>,</span> <span>'</span><span>yellow</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>duration</span><span>'</span><span>,</span> <span>duration</span><span>,</span> <span>'</span><span>green</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>time</span><span>'</span><span>,</span> <span>timestamp</span><span>,</span> <span>'</span><span>magenta</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>ip</span><span>'</span><span>,</span> <span>ip</span><span>,</span> <span>'</span><span>red</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>host</span><span>'</span><span>,</span> <span>host</span><span>,</span> <span>'</span><span>red</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>params</span><span>'</span><span>,</span> <span>args</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>)</span>
    <span>]</span>
    <span>request_id</span> <span>=</span> <span>request</span><span>.</span><span>headers</span><span>.</span><span>get</span><span>(</span><span>'</span><span>X-Request-ID</span><span>'</span><span>)</span>
    <span>if</span> <span>request_id</span><span>:</span>
        <span>log_params</span><span>.</span><span>append</span><span>((</span><span>'</span><span>request_id</span><span>'</span><span>,</span> <span>request_id</span><span>,</span> <span>'</span><span>yellow</span><span>'</span><span>))</span>
    <span>parts</span> <span>=</span> <span>[]</span>
    <span>for</span> <span>name</span><span>,</span> <span>value</span><span>,</span> <span>color</span> <span>in</span> <span>log_params</span><span>:</span>
        <span>part</span> <span>=</span> <span>colors</span><span>.</span><span>color</span><span>(</span><span>"</span><span>{}={}</span><span>"</span><span>.</span><span>format</span><span>(</span><span>name</span><span>,</span> <span>value</span><span>),</span> <span>fg</span><span>=</span><span>color</span><span>)</span>
        <span>parts</span><span>.</span><span>append</span><span>(</span><span>part</span><span>)</span>
    <span>line</span> <span>=</span> <span>"</span><span> </span><span>"</span><span>.</span><span>join</span><span>(</span><span>parts</span><span>)</span>
    <span>app</span><span>.</span><span>logger</span><span>.</span><span>info</span><span>(</span><span>line</span><span>)</span>
    <span>return</span> <span>response</span>
<span>import</span> <span>datetime</span>
<span>import</span> <span>time</span>

<span>import</span> <span>colors</span>
<span>from</span> <span>flask</span> <span>import</span> <span>g</span><span>,</span> <span>request</span>
<span>from</span> <span>rfc3339</span> <span>import</span> <span>rfc3339</span>

<span>app</span> <span>=</span> <span>create_your_flask_app</span><span>()</span>


<span>@app.before_request</span>
<span>def</span> <span>start_timer</span><span>():</span>
    <span>g</span><span>.</span><span>start</span> <span>=</span> <span>time</span><span>.</span><span>time</span><span>()</span>


<span>@app.after_request</span>
<span>def</span> <span>log_request</span><span>(</span><span>response</span><span>):</span>
    <span>if</span> <span>request</span><span>.</span><span>path</span> <span>==</span> <span>'</span><span>/favicon.ico</span><span>'</span><span>:</span>
        <span>return</span> <span>response</span>
    <span>elif</span> <span>request</span><span>.</span><span>path</span><span>.</span><span>startswith</span><span>(</span><span>'</span><span>/static</span><span>'</span><span>):</span>
        <span>return</span> <span>response</span>

    <span>now</span> <span>=</span> <span>time</span><span>.</span><span>time</span><span>()</span>
    <span>duration</span> <span>=</span> <span>round</span><span>(</span><span>now</span> <span>-</span> <span>g</span><span>.</span><span>start</span><span>,</span> <span>2</span><span>)</span>
    <span>dt</span> <span>=</span> <span>datetime</span><span>.</span><span>datetime</span><span>.</span><span>fromtimestamp</span><span>(</span><span>now</span><span>)</span>
    <span>timestamp</span> <span>=</span> <span>rfc3339</span><span>(</span><span>dt</span><span>,</span> <span>utc</span><span>=</span><span>True</span><span>)</span>

    <span>ip</span> <span>=</span> <span>request</span><span>.</span><span>headers</span><span>.</span><span>get</span><span>(</span><span>'</span><span>X-Forwarded-For</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>remote_addr</span><span>)</span>
    <span>host</span> <span>=</span> <span>request</span><span>.</span><span>host</span><span>.</span><span>split</span><span>(</span><span>'</span><span>:</span><span>'</span><span>,</span> <span>1</span><span>)[</span><span>0</span><span>]</span>
    <span>args</span> <span>=</span> <span>dict</span><span>(</span><span>request</span><span>.</span><span>args</span><span>)</span>

    <span>log_params</span> <span>=</span> <span>[</span>
        <span>(</span><span>'</span><span>method</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>method</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>path</span><span>'</span><span>,</span> <span>request</span><span>.</span><span>path</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>status</span><span>'</span><span>,</span> <span>response</span><span>.</span><span>status_code</span><span>,</span> <span>'</span><span>yellow</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>duration</span><span>'</span><span>,</span> <span>duration</span><span>,</span> <span>'</span><span>green</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>time</span><span>'</span><span>,</span> <span>timestamp</span><span>,</span> <span>'</span><span>magenta</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>ip</span><span>'</span><span>,</span> <span>ip</span><span>,</span> <span>'</span><span>red</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>host</span><span>'</span><span>,</span> <span>host</span><span>,</span> <span>'</span><span>red</span><span>'</span><span>),</span>
        <span>(</span><span>'</span><span>params</span><span>'</span><span>,</span> <span>args</span><span>,</span> <span>'</span><span>blue</span><span>'</span><span>)</span>
    <span>]</span>

    <span>request_id</span> <span>=</span> <span>request</span><span>.</span><span>headers</span><span>.</span><span>get</span><span>(</span><span>'</span><span>X-Request-ID</span><span>'</span><span>)</span>
    <span>if</span> <span>request_id</span><span>:</span>
        <span>log_params</span><span>.</span><span>append</span><span>((</span><span>'</span><span>request_id</span><span>'</span><span>,</span> <span>request_id</span><span>,</span> <span>'</span><span>yellow</span><span>'</span><span>))</span>

    <span>parts</span> <span>=</span> <span>[]</span>
    <span>for</span> <span>name</span><span>,</span> <span>value</span><span>,</span> <span>color</span> <span>in</span> <span>log_params</span><span>:</span>
        <span>part</span> <span>=</span> <span>colors</span><span>.</span><span>color</span><span>(</span><span>"</span><span>{}={}</span><span>"</span><span>.</span><span>format</span><span>(</span><span>name</span><span>,</span> <span>value</span><span>),</span> <span>fg</span><span>=</span><span>color</span><span>)</span>
        <span>parts</span><span>.</span><span>append</span><span>(</span><span>part</span><span>)</span>
    <span>line</span> <span>=</span> <span>"</span><span> </span><span>"</span><span>.</span><span>join</span><span>(</span><span>parts</span><span>)</span>

    <span>app</span><span>.</span><span>logger</span><span>.</span><span>info</span><span>(</span><span>line</span><span>)</span>

    <span>return</span> <span>response</span>


import datetime
import time

import colors
from flask import g, request
from rfc3339 import rfc3339

app = create_your_flask_app()


@app.before_request
def start_timer():
    g.start = time.time()


@app.after_request
def log_request(response):
    if request.path == '/favicon.ico':
        return response
    elif request.path.startswith('/static'):
        return response

    now = time.time()
    duration = round(now - g.start, 2)
    dt = datetime.datetime.fromtimestamp(now)
    timestamp = rfc3339(dt, utc=True)

    ip = request.headers.get('X-Forwarded-For', request.remote_addr)
    host = request.host.split(':', 1)[0]
    args = dict(request.args)

    log_params = [
        ('method', request.method, 'blue'),
        ('path', request.path, 'blue'),
        ('status', response.status_code, 'yellow'),
        ('duration', duration, 'green'),
        ('time', timestamp, 'magenta'),
        ('ip', ip, 'red'),
        ('host', host, 'red'),
        ('params', args, 'blue')
    ]

    request_id = request.headers.get('X-Request-ID')
    if request_id:
        log_params.append(('request_id', request_id, 'yellow'))

    parts = []
    for name, value, color in log_params:
        part = colors.color("{}={}".format(name, value), fg=color)
        parts.append(part)
    line = " ".join(parts)

    app.logger.info(line)

    return response

Enter fullscreen mode Exit fullscreen mode

原文链接：Logging Flask requests with structure and colors

展开阅读全文
© 版权声明
文章版权声明 1、本网站名称：拾光赋
2、本站永久网址：https://www.blogs.ink
3、本网站的文章部分内容可能来源于网络，仅供大家学习与参考，如有侵权，请联系站长QQ：805375623进行删除处理。
4、本站一切资源不代表本站立场，并不代表本站赞同其观点和对其真实性负责。
5、本站一律禁止以任何方式发布或转载任何违法的相关信息，访客发现请向站长举报
6、本站资源大多存储在云盘，如发现链接失效，请联系我们我们会第一时间更新。

THE END
Python（EN）
# python# flask# logging
喜欢就支持一下吧
点赞14 分享
The best way out is always through.
一路走到底，你就会发现那个最佳出口
kity的头像-拾光赋
相关推荐
评论 抢沙发

请登录后发表评论

    暂无评论内容

kity的头像-拾光赋
今日剩余 91.1%
本周剩余 41.6%
本月剩余 12.6%
本年剩余 76.4%
最近评论
Vito的头像-拾光赋

Vito5个月前2

你就是我心中的那首忐忑，总是让我惊心动魄
Jason.Meng的头像-拾光赋钻石会员

Jason.Meng徽章-人气大使-拾光赋5个月前2

总是会在人生的不同阶段反复爱上大佬的文章~
每日一言
Worrying does not empty tomorrow of its troubles, it empties today of its strength.
担忧不会清空明日的烦恼，它只会丧失今日的勇气