区块链web3项目系统开发技术方案丨DAPP系统开发技术讲解

2022-11-07 11:03:36 浏览数 (1)

  作为一种可能的Web3.0底层技术,区块链以去中心化、不可篡改、可溯源等特点,构建起数字经济时代的全新信任体系。

  从技术角度分析,区块链让数字资产价值流转的每一个节点都公开透明、有迹可循且不可篡改,这将会让Web3.0时代的一切交易变得更加真实可信。

应用场景

在容器内部,想要获取容器名称,替换容器内某些文件内的字符串, 代码如下:

代码语言:javascript复制
# -*-coding:utf-8-*-
import os
import redis


def alter(file, new_str, old_str="abc_123abc"):
    """
    替换文件中的字符串
    file:文件名
    old_str:就字符串
    new_str:新字符串
    """

    file_data = ""
    with open(file, "r") as f:
        for line in f:
            if old_str in line:
                line = line.replace(old_str, new_str)
            file_data  = line
    with open(file, "w") as f:
        f.write(file_data)


def get_container_name():
    db = redis.Redis(host="192.168.0.111", port=6380, decode_responses=False)
   
    # start: in container, run next code  -------------------------------------------------
    cmd = "cat /proc/self/cgroup"
    output = os.popen(cmd)
    rests = output.readlines()
    container_message= rests[-1]
    if not container_message:
        container_id = "abc"
    else:
        container_id =  container_message.strip().split("docker-")[-1][:12]
    # end. ----------------------------------------------------------------------------------

    container_name = None
    if container_id != "abc":
        key_name = "nm_"   container_id
        container_name = db.hget("container_msg", key_name)

    if container_name:
        container_name = container_name.decode("utf-8")

    return container_name


def run():
    nginx_conf = "/etc/nginx/nginx.conf"
    galaxy_yml = "/galaxy-central/config/galaxy.yml"

    container_name = get_container_name()
    if container_name is not None:
        alter(nginx_conf, container_name)
        os.popen("nginx -s reload")
        # os.popen("cp /galaxy-central/config/galaxy.yml.sample /galaxy-central/config/galaxy.yml")
        alter(galaxy_yml, container_name)
        print("Replacement string 'abc_123abc' succeeded")
    else:
        print("Replacement string 'abc_123abc' failed")
        

if __name__ == '__main__':
    run()

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代码语言:javascript复制
import os
    # 目标路径
    path = "C:\Users\username\Desktop\project"
    dir_list = []
    # os.walk() 自上而下或自下而上,遍历出所有文件。返回值 可迭代对象  
    # 当前路径(str),所有文件夹(list),所有文件(list)
    for dirpath, dirnames, filenames in os.walk(path):
        for filepath in filenames:
            print(os.path.join(dirpath, filepath))
            if os.path.join(dirpath, filepath).endswith(".py"):
                dir_list.append(os.path.join(dirpath, filepath))
        print(dir_list)

    for dir in dir_list:
        with open(dir, encoding="utf-8") as f:
            content = f.read()

        with open("project.txt", "a", encoding="utf-8") as file:
            file.write(content)

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