This forces an expansion failure (see section &<<SECTforexpfai>>&);
{<&'string2'&>} must be present for &"fail"& to be recognized.
+.new
+.vitem "&*${extract json{*&<&'key'&>&*}{*&<&'string1'&>&*}{*&<&'string2'&>&*}&&&
+ {*&<&'string3'&>&*}}*&"
+.cindex "expansion" "extracting from JSON object"
+.cindex JSON expansions
+The key and <&'string1'&> are first expanded separately. Leading and trailing
+white space is removed from the key (but not from any of the strings). The key
+must not be empty and must not consist entirely of digits.
+The expanded <&'string1'&> must be of the form:
+.display
+{ <&'"key1"'&> : <&'value1'&> , <&'"key2"'&> , <&'value2'&> ... }
+.endd
+.vindex "&$value$&"
+The braces, commas and colons, and the quoting of the member name are required;
+the spaces are optional.
+Matching of the key against the member names is done case-sensitively.
+. XXX should be a UTF-8 compare
+
+The results of matching are handled as above.
+.wen
+
.vitem "&*${extract{*&<&'number'&>&*}{*&<&'separators'&>&*}&&&
{*&<&'string1'&>&*}{*&<&'string2'&>&*}{*&<&'string3'&>&*}}*&"
empty (for example, the fifth field above).
+.new
+.vitem "&*${extract json{*&<&'number'&>&*}}&&&
+ {*&<&'string1'&>&*}{*&<&'string2'&>&*}{*&<&'string3'&>&*}}*&"
+.cindex "expansion" "extracting from JSON array"
+.cindex JSON expansions
+The <&'number'&> argument must consist entirely of decimal digits,
+apart from leading and trailing white space, which is ignored.
+
+Field selection and result handling is as above;
+there is no choice of field separator.
+.wen
+
+
.vitem &*${filter{*&<&'string'&>&*}{*&<&'condition'&>&*}}*&
.cindex "list" "selecting by condition"
.cindex "expansion" "selecting from list by condition"
*/
static uschar *
-expand_getkeyed(uschar *key, const uschar *s)
+expand_getkeyed(uschar * key, const uschar * s)
{
int length = Ustrlen(key);
while (isspace(*s)) s++;
/* Loop to search for the key */
-while (*s != 0)
+while (*s)
{
int dkeylength;
- uschar *data;
- const uschar *dkey = s;
+ uschar * data;
+ const uschar * dkey = s;
- while (*s != 0 && *s != '=' && !isspace(*s)) s++;
+ while (*s && *s != '=' && !isspace(*s)) s++;
dkeylength = s - dkey;
while (isspace(*s)) s++;
if (*s == '=') while (isspace((*(++s))));
static uschar *
expand_getlistele(int field, const uschar * list)
{
-const uschar * tlist= list;
-int sep= 0;
+const uschar * tlist = list;
+int sep = 0;
uschar dummy;
-if(field<0)
+if (field < 0)
{
- for(field++; string_nextinlist(&tlist, &sep, &dummy, 1); ) field++;
- sep= 0;
+ for (field++; string_nextinlist(&tlist, &sep, &dummy, 1); ) field++;
+ sep = 0;
}
-if(field==0) return NULL;
-while(--field>0 && (string_nextinlist(&list, &sep, &dummy, 1))) ;
+if (field == 0) return NULL;
+while (--field > 0 && (string_nextinlist(&list, &sep, &dummy, 1))) ;
return string_nextinlist(&list, &sep, NULL, 0);
}
+/* Return pointer to dewrapped string, with enclosing specified chars removed.
+The given string is modified on return. Leading whitespace is skipped while
+looking for the opening wrap character, then the rest is scanned for the trailing
+(non-escaped) wrap character. A backslash in the string will act as an escape.
+
+A nul is written over the trailing wrap, and a pointer to the char after the
+leading wrap is returned.
+
+Arguments:
+ s String for de-wrapping
+ wrap Two-char string, the first being the opener, second the closer wrapping
+ character
+Return:
+ Pointer to de-wrapped string, or NULL on error (with expand_string_message set).
+*/
+
+static uschar *
+dewrap(uschar * s, const uschar * wrap)
+{
+uschar * p = s;
+
+while (isspace(*p)) p++;
+
+if (*p == *wrap)
+ {
+ s = ++p;
+ wrap++;
+ while (*p)
+ {
+ if (*p == '\\') p++;
+ else if (*p == *wrap)
+ {
+ *p = '\0';
+ return s;
+ }
+ p++;
+ }
+ }
+expand_string_message = string_sprintf("missing '%c'", *wrap);
+return NULL;
+}
+
+
+/* Pull off the leading array or object element, returning
+a copy in an allocated string. Update the list pointer.
+
+The element may itself be an abject or array.
+*/
+
+uschar *
+json_nextinlist(const uschar ** list)
+{
+unsigned array_depth = 0, object_depth = 0;
+const uschar * s = *list, * item;
+
+while (isspace(*s)) s++;
+
+for (item = s;
+ *s && (*s != ',' || array_depth != 0 || object_depth != 0);
+ s++)
+ switch (*s)
+ {
+ case '[': array_depth++; break;
+ case ']': array_depth--; break;
+ case '{': object_depth++; break;
+ case '}': object_depth--; break;
+ }
+*list = *s ? s+1 : s;
+return string_copyn(item, s - item);
+}
+
+
+
/*************************************************
* Expand string *
*************************************************/
uschar *sub[3];
int save_expand_nmax =
save_expand_strings(save_expand_nstring, save_expand_nlength);
+ enum {extract_basic, extract_json} fmt = extract_basic;
+
+ while (isspace(*s)) s++;
+
+ /* Check for a format-variant specifier */
+
+ if (*s != '{') /*}*/
+ {
+ if (Ustrncmp(s, "json", 4) == 0) {fmt = extract_json; s += 4;}
+ }
/* While skipping we cannot rely on the data for expansions being
available (eg. $item) hence cannot decide on numeric vs. keyed.
if (skipping)
{
- while (isspace(*s)) s++;
- for (j = 5; j > 0 && *s == '{'; j--)
+ for (j = 5; j > 0 && *s == '{'; j--) /*'}'*/
{
if (!expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok))
- goto EXPAND_FAILED; /*{*/
+ goto EXPAND_FAILED; /*'{'*/
if (*s++ != '}')
{
expand_string_message = US"missing '{' for arg of extract";
}
while (isspace(*s)) s++;
}
- if ( Ustrncmp(s, "fail", 4) == 0
+ if ( Ustrncmp(s, "fail", 4) == 0 /*'{'*/
&& (s[4] == '}' || s[4] == ' ' || s[4] == '\t' || !s[4])
)
{
s += 4;
while (isspace(*s)) s++;
- }
+ } /*'{'*/
if (*s != '}')
{
expand_string_message = US"missing '}' closing extract";
else for (i = 0, j = 2; i < j; i++) /* Read the proper number of arguments */
{
- while (isspace(*s)) s++;
- if (*s == '{') /*}*/
+ while (isspace(*s)) s++;
+ if (*s == '{') /*'}'*/
{
sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
- if (sub[i] == NULL) goto EXPAND_FAILED; /*{*/
+ if (sub[i] == NULL) goto EXPAND_FAILED; /*'{'*/
if (*s++ != '}')
{
expand_string_message = string_sprintf(
/* After removal of leading and trailing white space, the first
argument must not be empty; if it consists entirely of digits
(optionally preceded by a minus sign), this is a numerical
- extraction, and we expect 3 arguments. */
+ extraction, and we expect 3 arguments (normal) or 2 (json). */
if (i == 0)
{
if (*p == 0)
{
field_number *= x;
- j = 3; /* Need 3 args */
+ if (fmt != extract_json) j = 3; /* Need 3 args */
field_number_set = TRUE;
}
}
/* Extract either the numbered or the keyed substring into $value. If
skipping, just pretend the extraction failed. */
- lookup_value = skipping? NULL : field_number_set?
- expand_gettokened(field_number, sub[1], sub[2]) :
- expand_getkeyed(sub[0], sub[1]);
+ if (skipping)
+ lookup_value = NULL;
+ else switch (fmt)
+ {
+ case extract_basic:
+ lookup_value = field_number_set
+ ? expand_gettokened(field_number, sub[1], sub[2])
+ : expand_getkeyed(sub[0], sub[1]);
+ break;
+
+ case extract_json:
+ {
+ uschar * s, * item;
+ const uschar * list;
+
+ /* Array: Bracket-enclosed and comma-separated.
+ Object: Brace-enclosed, comma-sep list of name:value pairs */
+
+ if (!(s = dewrap(sub[1], field_number_set ? US"[]" : US"{}")))
+ {
+ expand_string_message =
+ string_sprintf("%s wrapping %s for extract json",
+ expand_string_message,
+ field_number_set ? "array" : "object");
+ goto EXPAND_FAILED_CURLY;
+ }
+
+ list = s;
+ if (field_number_set)
+ {
+ if (field_number <= 0)
+ {
+ expand_string_message = US"first argument of \"extract\" must "
+ "be greater than zero";
+ goto EXPAND_FAILED;
+ }
+ while (field_number > 0 && (item = json_nextinlist(&list)))
+ field_number--;
+ s = item;
+ lookup_value = s;
+ while (*s) s++;
+ while (--s >= lookup_value && isspace(*s)) *s = '\0';
+ }
+ else
+ {
+ lookup_value = NULL;
+ while ((item = json_nextinlist(&list)))
+ {
+ /* Item is: string name-sep value. string is quoted.
+ Dequote the string and compare with the search key. */
+
+ if (!(item = dewrap(item, US"\"\"")))
+ {
+ expand_string_message =
+ string_sprintf("%s wrapping string key for extract json",
+ expand_string_message);
+ goto EXPAND_FAILED_CURLY;
+ }
+ if (Ustrcmp(item, sub[0]) == 0) /*XXX should be a UTF8-compare */
+ {
+ s = item + strlen(item) + 1;
+ while (isspace(*s)) s++;
+ if (*s != ':')
+ {
+ expand_string_message = string_sprintf(
+ "missing object value-separator for extract json");
+ goto EXPAND_FAILED_CURLY;
+ }
+ s++;
+ while (isspace(*s)) s++;
+ lookup_value = s;
+ break;
+ }
+ }
+ }
+ }
+ }
/* If no string follows, $value gets substituted; otherwise there can
be yes/no strings, as for lookup or if. */
/* Extract the numbered element into $value. If
skipping, just pretend the extraction failed. */
- lookup_value = skipping? NULL : expand_getlistele(field_number, sub[1]);
+ lookup_value = skipping ? NULL : expand_getlistele(field_number, sub[1]);
/* If no string follows, $value gets substituted; otherwise there can
be yes/no strings, as for lookup or if. */