Question

在aws api网关中，我想通过api网关将整个查询字符串传递给kinesis，

#set($querystring = $input.params().querystring)
"Data": "$util.base64Encode($querystring)"

但是从kinesis记录中获取的数据看起来像'{tracker_name = xxxx，tracker = yyyy}'，这不是json字符串格式，所以我需要特别注意这个奇怪的字符串，使其成为aws中的json字符串lambda（Python引擎）。有什么好主意吗？

Answer 1

我不熟悉AWS API网关，但专注于字符串格式化问题，编写一个简单的解析器将其转换为您想要的任何其他格式并不难。

至于你的描述，我写了一个简单的Python解析器，希望它可以给你一些想法。

class MyParser:

def __init__(self, source):
    # the source string
    self.source = source
    # current position
    self.at = 0
    # current character
    self.ch = source[0] if len(source) > 0 else ''

def error(self, msg):
    '''Print an error message and raise an exception'''

    print '-- Parser abort due to a fatal error: \n-- %s' % msg
    raise ValueError()

def check_char(self, expected):
    '''
    Check if current character is same as the given character.
    If not, raise an exception.
    '''

    if self.at >= len(self.source):
        self.error('At position %d: %c expected, but reached string end' % (self.at, expected))
    elif self.ch != expected:
        self.error('At position %d: %c expected, but %c given' % (self.at, expected, self.ch))

def next_char(self):
    '''Move on to next character in source string.'''

    self.at += 1
    self.ch = self.source[self.at] if len(self.source) > self.at else ''
    return self.ch

def eat_spaces(self):
    '''Eat up white spaces.'''

    while self.ch == ' ':
        self.next_char()

def parse_string(self):
    '''Parse a string value.'''

    s = ''
    while self.ch != '=' and self.ch != ',' and self.ch != '}' and self.at < len(self.source):
        s += self.ch
        self.next_char()
    return s.strip()

def parse_object(self):
    '''Parse an object value.'''

    obj = {}

    # eat '{'
    self.next_char()
    self.eat_spaces()

    while self.ch != '}':
        if self.at >= len(self.source):
            self.error('Malformed source string')

        key = self.parse_string()
        # eat '='
        self.check_char('=')
        self.next_char()
        val = self.parse_value()
        obj[key] = val
        # eat ','
        if self.ch == ',':
            self.next_char()
        self.eat_spaces()

    # eat '}'
    self.next_char()

    return obj

def parse_value(self):
    '''Parse a value.'''

    self.eat_spaces()
    if self.ch == '{':
        return self.parse_object()
    else:
        return self.parse_string()

def parse(self):
    '''Let the game begin.'''

    self.eat_spaces()
    if self.ch != '{':
        self.error('Source string must begin with \'{\'')
    else:
        return self.parse_value()

使用它：

MyParser('{tracker_name=xxxx, tracker=yyyy}').parse()

AWS API Gateway的查询字符串不是json格式

1 个答案: