FastAPI部署-docker篇

    FastAPI是一种现代，快速（高性能）的Web框架，用于基于标准Python类型提示使用Python 3.6+构建API,对飚go和nodejs。

 FastAPI github地址：https://github.com/tiangolo/fastapi

Uvicorn

Uvicorn是一款闪电般的“ ASGI”服务器。

它在单个过程中运行异步Python Web代码。

Gunicorn

您可以使用Gunicorn管理Uvicorn和运行多个这些并发进程。

这样，您将获得最佳的并发性和并行性。

FastAPI

FastAPI是一种现代，快速（高性能）的Web框架，用于使用Python 3.6+构建API。

步骤一：创建dockfile

#Dockerfile

FROM tiangolo/uvicorn-gunicorn-fastapi:python3.7

COPY ./app /app

dockerfile的意思就是把当前目录（./app）复制到 /app文件夹中。

步骤二：创建FastAPI文件

mkdir app

vim main.py

main.py文件内容如下：

from fastapi import FastAPI

app = FastAPI()

@app.get("/")

def read_root():

       return {"Hello": "World"}

@app.get("/items/{item_id}")

def read_item(item_id: int, q: str = None):

       return {"item_id": item_id, "q": q}

目录结构如下：

├── app

│   └── main.py

└── Dockerfile

步骤三：创建镜像

docker build -t fastapi_image ./

Sending build context to Docker daemon 3.584kB

Step 1/2 : FROM tiangolo/uvicorn-gunicorn-fastapi:python3.7

---> 23579a0a7c50

Step 2/2 : COPY ./app /app

---> Using cache

---> 8c41afea5ee1

Successfully built 8c41afea5ee1

Successfully tagged fastapi_image:latest

查看创建的image

docker image ls|grep fastapi_image

步骤四：启动应用

docker run -d --name fastapi_container -p 10001:80 fastapi_image

15984271b4792db1025224da534be5951307b8433dc8e41babbcba073a2baa24

查看刚才启动的应用

docker container ls |grep fastapi

15984271b479 fastapi_image "/start.sh" About a minute ago Up About a minute 0.0.0.0:10001->80/tcp fastapi_container

步骤五：访问应用

通过浏览器  http://ip地址:10001

或者命令行：curl http://127.0.0.1:10001

{"Hello":"World"}

http://127.0.0.1/docs   #API文档

http://127.0.0.1/redoc  #备用API文档

下面我们来分析下镜像的构建过程：

docker image ls |grep fastapi

docker history fastapi_image:latest

[root@kube-test-master ~]# docker history fastapi_image:latest

IMAGE              CREATED            CREATED BY                                      SIZE                COMMENT

8c41afea5ee1        2 days ago          /bin/sh -c #(nop) COPY dir:d1727655ba287a3f2…  223B               

23579a0a7c50        5 weeks ago        /bin/sh -c #(nop) COPY dir:81482727cef4cc213…  292B               

<missing>          5 weeks ago        /bin/sh -c pip install --no-cache-dir fastapi  25.4MB             

<missing>          5 weeks ago        /bin/sh -c #(nop)  LABEL maintainer=Sebastia…  0B                 

<missing>          5 weeks ago        /bin/sh -c #(nop)  CMD ["/start.sh"]            0B                 

<missing>          5 weeks ago        /bin/sh -c #(nop)  EXPOSE 80                    0B                 

<missing>          5 weeks ago        /bin/sh -c #(nop)  ENV PYTHONPATH=/app          0B                 

<missing>          5 weeks ago        /bin/sh -c #(nop) WORKDIR /app/                0B                 

<missing>          5 weeks ago        /bin/sh -c #(nop) COPY dir:2e485a98ab454814a…  844B               

<missing>          5 weeks ago        /bin/sh -c chmod +x /start-reload.sh            848B               

<missing>          5 weeks ago        /bin/sh -c #(nop) COPY file:1ee462cef5d29106…  848B               

<missing>          5 weeks ago        /bin/sh -c #(nop) COPY file:64f25d957a18eec5…  1.94kB             

<missing>          5 weeks ago        /bin/sh -c chmod +x /start.sh                  1.11kB             

<missing>          5 weeks ago        /bin/sh -c #(nop) COPY file:46531dace36927e7…  1.11kB             

<missing>          5 weeks ago        /bin/sh -c pip install --no-cache-dir uvicor…  25.5MB             

<missing>          5 weeks ago        /bin/sh -c #(nop)  LABEL maintainer=Sebastia…  0B                 

<missing>          6 weeks ago        /bin/sh -c #(nop)  CMD ["python3"]              0B                 

<missing>          6 weeks ago        /bin/sh -c set -ex;  wget -O get-pip.py "$P…  6.34MB             

<missing>          6 weeks ago        /bin/sh -c #(nop)  ENV PYTHON_GET_PIP_SHA256…  0B                 

<missing>          6 weeks ago        /bin/sh -c #(nop)  ENV PYTHON_GET_PIP_URL=ht…  0B                 

<missing>          6 weeks ago        /bin/sh -c #(nop)  ENV PYTHON_PIP_VERSION=20…  0B                 

<missing>          6 weeks ago        /bin/sh -c cd /usr/local/bin  && ln -s idle3…  32B               

<missing>          6 weeks ago        /bin/sh -c set -ex  && wget -O python.tar.x…  91MB               

<missing>          6 weeks ago        /bin/sh -c #(nop)  ENV PYTHON_VERSION=3.7.7    0B                 

<missing>          6 weeks ago        /bin/sh -c #(nop)  ENV GPG_KEY=0D96DF4D4110E…  0B                 

<missing>          6 weeks ago        /bin/sh -c apt-get update && apt-get install…  17.9MB             

<missing>          6 weeks ago        /bin/sh -c #(nop)  ENV LANG=C.UTF-8            0B                 

<missing>          6 weeks ago        /bin/sh -c #(nop)  ENV PATH=/usr/local/bin:/…  0B                 

<missing>          6 weeks ago        /bin/sh -c set -ex;  apt-get update;  DEBIAN…  510MB             

<missing>          6 weeks ago        /bin/sh -c apt-get update && apt-get install…  146MB             

<missing>          6 weeks ago        /bin/sh -c set -ex;  if ! command -v gpg > /…  17.5MB             

<missing>          6 weeks ago        /bin/sh -c apt-get update && apt-get install…  16.5MB             

<missing>          6 weeks ago        /bin/sh -c #(nop)  CMD ["bash"]                0B                 

<missing>          6 weeks ago        /bin/sh -c #(nop) ADD file:f086177965196842a…  114MB   

由以上信息可以知道workdir 是/app,应用启动脚本start.sh，重启脚本start-reload.sh

进入容器进一步验证

docker container ls |grep fastapi

15984271b479 fastapi_image "/start.sh" 34 minutes ago Up 34 minutes 0.0.0.0:10001->80/tcp fastapi_container

docker exec -it 15984271b479 /bin/bash

root@15984271b479:/app# ls

__pycache__  main.py  prestart.sh

root@15984271b479:/app# cd ..

root@15984271b479:/# ls

app  boot  etc              home  lib64  mnt  proc  run  srv              start.sh  tmp  var

bin  dev  gunicorn_conf.py  lib  media  opt  root  sbin  start-reload.sh  sys      usr

root@15984271b479:/#

start.sh  start-reload.sh位于根目录

root@15984271b479:/# cat start.sh

#! /usr/bin/env sh

set -e

if [ -f /app/app/main.py ]; then

    DEFAULT_MODULE_NAME=app.main

elif [ -f /app/main.py ]; then

    DEFAULT_MODULE_NAME=main

fi

MODULE_NAME=${MODULE_NAME:-$DEFAULT_MODULE_NAME}

VARIABLE_NAME=${VARIABLE_NAME:-app}

export APP_MODULE=${APP_MODULE:-"$MODULE_NAME:$VARIABLE_NAME"}

if [ -f /app/gunicorn_conf.py ]; then

    DEFAULT_GUNICORN_CONF=/app/gunicorn_conf.py

elif [ -f /app/app/gunicorn_conf.py ]; then

    DEFAULT_GUNICORN_CONF=/app/app/gunicorn_conf.py

else

    DEFAULT_GUNICORN_CONF=/gunicorn_conf.py

fi

export GUNICORN_CONF=${GUNICORN_CONF:-$DEFAULT_GUNICORN_CONF}

export WORKER_CLASS=${WORKER_CLASS:-"uvicorn.workers.UvicornWorker"}

# If there's a prestart.sh script in the /app directory or other path specified, run it before starting

PRE_START_PATH=${PRE_START_PATH:-/app/prestart.sh}

echo "Checking for script in $PRE_START_PATH"

if [ -f $PRE_START_PATH ] ; then

    echo "Running script $PRE_START_PATH"

    . "$PRE_START_PATH"

else

    echo "There is no script $PRE_START_PATH"

fi

# Start Gunicorn

exec gunicorn -k "$WORKER_CLASS" -c "$GUNICORN_CONF" "$APP_MODULE"

gunicorn_conf.py

root@15984271b479:/# cat gunicorn_conf.py

import json

import multiprocessing

import os

workers_per_core_str = os.getenv("WORKERS_PER_CORE", "1")

max_workers_str = os.getenv("MAX_WORKERS")

use_max_workers = None

if max_workers_str:

    use_max_workers = int(max_workers_str)

web_concurrency_str = os.getenv("WEB_CONCURRENCY", None)

host = os.getenv("HOST", "0.0.0.0")

port = os.getenv("PORT", "80")

bind_env = os.getenv("BIND", None)

use_loglevel = os.getenv("LOG_LEVEL", "info")

if bind_env:

    use_bind = bind_env

else:

    use_bind = f"{host}:{port}"

cores = multiprocessing.cpu_count()

workers_per_core = float(workers_per_core_str)

default_web_concurrency = workers_per_core * cores

if web_concurrency_str:

    web_concurrency = int(web_concurrency_str)

    assert web_concurrency > 0

else:

    web_concurrency = max(int(default_web_concurrency), 2)

    if use_max_workers:

        web_concurrency = min(web_concurrency, use_max_workers)

accesslog_var = os.getenv("ACCESS_LOG", "-")

use_accesslog = accesslog_var or None

errorlog_var = os.getenv("ERROR_LOG", "-")

use_errorlog = errorlog_var or None

graceful_timeout_str = os.getenv("GRACEFUL_TIMEOUT", "120")

timeout_str = os.getenv("TIMEOUT", "120")

keepalive_str = os.getenv("KEEP_ALIVE", "5")

# Gunicorn config variables

loglevel = use_loglevel

workers = web_concurrency

bind = use_bind

errorlog = use_errorlog

worker_tmp_dir = "/dev/shm"

accesslog = use_accesslog

graceful_timeout = int(graceful_timeout_str)

timeout = int(timeout_str)

keepalive = int(keepalive_str)

# For debugging and testing

log_data = {

    "loglevel": loglevel,

    "workers": workers,

    "bind": bind,

    "graceful_timeout": graceful_timeout,

    "timeout": timeout,

    "keepalive": keepalive,

    "errorlog": errorlog,

    "accesslog": accesslog,

    # Additional, non-gunicorn variables

    "workers_per_core": workers_per_core,

    "use_max_workers": use_max_workers,

    "host": host,

    "port": port,

}

print(json.dumps(log_data))

其中有两个变量 ACCESS_LOG  ERROR_LOG是日志输出的路径，如果没定义默认不输出日志。

如果是正式环境，建议设置路径。具体见官方文档，并使用 -v参数映射到宿主机目录。

docker container logs fastapi_container  查看容器logs

docker container inspect fastapi_container 

可以获取容器的详细信息

其中id 15984271b4792db1025224da534be5951307b8433dc8e41babbcba073a2baa24

存放路径位置

/var/lib/docker/containers/15984271b4792db1025224da534be5951307b8433dc8e41babbcba073a2baa24

{"log":"{\"loglevel\": \"info\", \"workers\": 2, \"bind\": \"0.0.0.0:80\", \"graceful_timeout\": 120, \"timeout\": 120, \"keepa

live\": 5, \"errorlog\": \"-\", \"accesslog\": \"-\", \"workers_per_core\": 1.0, \"use_max_workers\": null, \"host\": \"0.0.0.0

\", \"port\": \"80\"}\n","stream":"stdout","time":"2020-06-08T01:58:54.535459288Z"}

{"log":"192.168.101.202:62512 - \"GET / HTTP/1.1\" 200\n","stream":"stdout","time":"2020-06-08T01:58:54.535495087Z"}

{"log":"192.168.101.202:62512 - \"GET /favicon.ico HTTP/1.1\" 404\n","stream":"stdout","time":"2020-06-08T01:58:55.271215897Z"}

{"log":"172.17.0.1:41038 - \"GET / HTTP/1.1\" 200\n","stream":"stdout","time":"2020-06-08T02:00:02.409539216Z"}

{"log":"{\"loglevel\": \"info\", \"workers\": 2, \"bind\": \"0.0.0.0:80\", \"graceful_timeout\": 120, \"timeout\": 120, \"keepa

live\": 5, \"errorlog\": \"-\", \"accesslog\": \"-\", \"workers_per_core\": 1.0, \"use_max_workers\": null, \"host\": \"0.0.0.0

\", \"port\": \"80\"}\n","stream":"stdout","time":"2020-06-08T02:00:07.276382848Z"}

{"log":"172.17.0.1:41074 - \"GET / HTTP/1.1\" 200\n","stream":"stdout","time":"2020-06-08T02:00:07.276421756Z"}