Python函数返回ACL检查结果格式异常问题求助

我在编写ACL流量检查的Python代码时，调用l.link()函数返回的是字典结构，无法生成带分隔线、规则详情的可读格式化文本。目前函数return的是字典数据，需要修改代码让return返回符合预期格式的文本。

相关代码 #

import link as l  # 用于检查ACL流量的Python代码

def t2e(src,dst,port,protocol):
    """
        acl output
        :param src : source ip
        :param dst : destination ip
        :param port : port
        :param protocol : protocol filed
        :args : source port
        :return : output
    """
    aclname = "t2e.jcl"
    dc = "abc"
    rpmName = "man-acl"
    ar.downloadlatestartifact(rpmName, aclDirName, dc)
    aclPath = "".join([aclDirName, f"/opt/manual-acl/acls/{aclname}"])
    
    print(f"output for {aclname.upper()}: {output(src, dst, port, protocol, aclPath)}")
    
def output(src,dst,port,protocol,aclPath,*args):
    """
        ACL output
        :param src : source ip
        :param dst : destination ip
        :param port : port
        :param protocol : protocol filed
        :param acl_path : acl path where it is stored
        :args : source port
        :return : hunter output
    """
    logger.info("flow is running against required acl")
    
    option = {'dport': port, 'proto': protocol, 'showallmatches': True}
    return l.link(src, dst, files=[aclPath], opts=option)

预期输出格式 #

############ CHECKING FLOW ############
8.8.8.8 -> 101.11.24.56 Dest Port:  443 Source Port:  0 Protocol: tcp
############## ACL CHECK ##############
Processing file: /var/folders/z6/1h1wt5x92rl9y4fsvh2j8y1c0000gp/T/tmpihe16vau/opt/m-acl/acls/t2e.jcl- HIT!!
Link Rule number: 11
Rule name: term web
Source Address: 0.0.0.0/0.0.0.0
Destination Address: 0.0.0.0/0.0.0.0
Destination Port: 25,8443,9443
Source Port: 0
Protocol: tcp
Application: 
Wildcard: False
Action: PERMIT

当前return返回格式 #

{
    'Hunter output for TRANSIT2EDGE.JCL': {
        '/var/folders/z6/1h1wt5x92rl9y4fsvh2j8y1c0000gp/T/tmpihe16vau/opt/m-acl/acls/t2e.jcl': [
            ['term web-axm', '0.0.0.0/0.0.0.0', '0.0.0.0/0.0.0.0', '25,53,80,81,443,4309,8443,9443', '0', 'tcp', True, False, '', '', False, False, '', '', '', None, 'cde01edef036a4182afec9a6b8c72d63f0f1a6cb2e7d66f7e36bb3918f0dd106']
        ]
    }
}

解决思路 #

解析l.link()返回的字典数据，提取关键字段后按照预期格式拼接成字符串，修改output函数的return逻辑返回格式化后的文本。

修改后的代码 #

import link as l  # 用于检查ACL流量的Python代码

def t2e(src,dst,port,protocol):
    """
        acl output
        :param src : source ip
        :param dst : destination ip
        :param port : port
        :param protocol : protocol filed
        :args : source port
        :return : output
    """
    aclname = "t2e.jcl"
    dc = "abc"
    rpmName = "man-acl"
    ar.downloadlatestartifact(rpmName, aclDirName, dc)
    aclPath = "".join([aclDirName, f"/opt/manual-acl/acls/{aclname}"])
    
    # 直接打印格式化后的结果
    print(output(src, dst, port, protocol, aclPath))
    
def output(src,dst,port,protocol,aclPath,*args):
    """
        ACL output
        :param src : source ip
        :param dst : destination ip
        :param port : port
        :param protocol : protocol filed
        :param acl_path : acl path where it is stored
        :args : source port
        :return : hunter output
    """
    logger.info("flow is running against required acl")
    
    option = {'dport': port, 'proto': protocol, 'showallmatches': True}
    # 获取字典结果
    result_dict = l.link(src, dst, files=[aclPath], opts=option)
    
    # 解析字典数据
    top_key = next(iter(result_dict.keys()))
    file_path = next(iter(result_dict[top_key].keys()))
    rules = result_dict[top_key][file_path]
    
    # 拼接格式化文本
    output_lines = []
    # 流量检查头部
    output_lines.append("############ CHECKING FLOW ############")
    # 流量信息
    source_port = args[0] if args else 0
    output_lines.append(f"{src} -> {dst} Dest Port:  {port} Source Port:  {source_port} Protocol: {protocol}")
    # ACL检查头部
    output_lines.append("############## ACL CHECK ##############")
    # 文件处理行
    output_lines.append(f"Processing file: {file_path}- HIT!!")
    
    # 遍历规则（支持多条规则）
    for idx, rule in enumerate(rules, 1):
        # 按返回列表顺序映射字段
        rule_name, src_addr, dst_addr, dst_ports, src_port, proto, _, wildcard, _, _, _, _, _, _, _, _, _ = rule
        output_lines.append(f"Link Rule number: {idx}")
        output_lines.append(f"Rule name: {rule_name}")
        output_lines.append(f"Source Address: {src_addr}")
        output_lines.append(f"Destination Address: {dst_addr}")
        output_lines.append(f"Destination Port: {dst_ports}")
        output_lines.append(f"Source Port: {src_port}")
        output_lines.append(f"Protocol: {proto}")
        output_lines.append("Application: ")
        output_lines.append(f"Wildcard: {wildcard}")
        output_lines.append("Action: PERMIT")  # 若有对应字段可替换为动态值
    
    # 拼接所有行并返回
    formatted_output = "\n".join(output_lines)
    return formatted_output

关键说明 #

1. 字典解析：通过next(iter(...))快速提取字典中的动态键值，避免硬编码键名。
2. 字段映射：根据当前l.link()返回的规则列表顺序，对应到预期输出的各个字段，若字段顺序变化需同步调整。
3. 文本拼接：逐行构建格式化内容，最后用换行符连接成完整字符串返回。
4. 源端口处理：通过*args接收可选的源端口参数，默认值设为0。

内容的提问来源于stack exchange，提问作者shivram