如何在Apache上使用RewriteCond的"AND","OR"？

Question

这是如何RewriteCond在Apache上使用AND,OR ？

rewritecond A [or]
rewritecond B
rewritecond C [or]
rewritecond D
RewriteRule ... something

成为if ( (A or B) and (C or D) ) rewrite_it.

所以看起来"OR"的优先级高于"AND"？有没有办法轻松讲述,比如 (A or B) and (C or D)语法？

Answer 1

这是一个有趣的问题,因为在文档中没有非常明确地解释,我将通过浏览mod_rewrite的源代码来回答这个问题.展示了开源的巨大好处.

在顶部,您将快速找到用于命名这些标志的定义:

#define CONDFLAG_NONE               1<<0
#define CONDFLAG_NOCASE             1<<1
#define CONDFLAG_NOTMATCH           1<<2
#define CONDFLAG_ORNEXT             1<<3
#define CONDFLAG_NOVARY             1<<4

并且搜索CONDFLAG_ORNEXT确认它是根据[OR]标志的存在使用的:

else if (   strcasecmp(key, "ornext") == 0
         || strcasecmp(key, "OR") == 0    ) {
    cfg->flags |= CONDFLAG_ORNEXT;
}

下一次出现的标志是实际的实现,你可以在其中找到经过RewriteRule所有RewriteConditions的循环,它基本上做的是(剥离,为了清晰起见添加了注释):

# loop through all Conditions that precede this Rule
for (i = 0; i < rewriteconds->nelts; ++i) {
    rewritecond_entry *c = &conds[i];

    # execute the current Condition, see if it matches
    rc = apply_rewrite_cond(c, ctx);

    # does this Condition have an 'OR' flag?
    if (c->flags & CONDFLAG_ORNEXT) {
        if (!rc) {
            /* One condition is false, but another can be still true. */
            continue;
        }
        else {
            /* skip the rest of the chained OR conditions */
            while (   i < rewriteconds->nelts
                   && c->flags & CONDFLAG_ORNEXT) {
                c = &conds[++i];
            }
        }
    }
    else if (!rc) {
        return 0;
    }
}

你应该能够解释这个; 这意味着OR具有更高的优先级,并且您的示例确实会导致if ( (A OR B) AND (C OR D) ).例如,如果您有这些条件:

RewriteCond A [or]
RewriteCond B [or]
RewriteCond C
RewriteCond D

它将被解释为if ( (A OR B OR C) and D ).

Answer 2

经过多次努力并获得通用、灵活且更具可读性的解决方案，在我的情况下，我最终将OR的结果保存到ENV变量中，并对这些变量进行AND运算。

# RESULT_ONE = A OR B
RewriteRule ^ - [E=RESULT_ONE:False]
RewriteCond ...A... [OR]
RewriteCond ...B...
RewriteRule ^ - [E=RESULT_ONE:True]

# RESULT_TWO = C OR D
RewriteRule ^ - [E=RESULT_TWO:False]
RewriteCond ...C... [OR]
RewriteCond ...D...
RewriteRule ^ - [E=RESULT_TWO:True]

# if ( RESULT_ONE AND RESULT_TWO ) then ( RewriteRule ...something... )
RewriteCond %{ENV:RESULT_ONE} =True
RewriteCond %{ENV:RESULT_TWO} =True
RewriteRule ...something...

要求：

• Apache mod_env 已启用