/* JSONPath 0.8.0 - XPath for JSON | |
* | |
* Copyright (c) 2007 Stefan Goessner (goessner.net) | |
* Licensed under the MIT (MIT-LICENSE.txt) licence. | |
*/ | |
function jsonPath(obj, expr, arg) { | |
var P = { | |
resultType: arg && arg.resultType || "VALUE", | |
result: [], | |
normalize: function(expr) { | |
var subx = []; | |
return expr.replace(/[\['](\??\(.*?\))[\]']/g, function($0,$1){return "[#"+(subx.push($1)-1)+"]";}) | |
.replace(/'?\.'?|\['?/g, ";") | |
.replace(/;;;|;;/g, ";..;") | |
.replace(/;$|'?\]|'$/g, "") | |
.replace(/#([0-9]+)/g, function($0,$1){return subx[$1];}); | |
}, | |
asPath: function(path) { | |
var x = path.split(";"), p = "$"; | |
for (var i=1,n=x.length; i<n; i++) | |
p += /^[0-9*]+$/.test(x[i]) ? ("["+x[i]+"]") : ("['"+x[i]+"']"); | |
return p; | |
}, | |
store: function(p, v) { | |
if (p) P.result[P.result.length] = P.resultType == "PATH" ? P.asPath(p) : v; | |
return !!p; | |
}, | |
trace: function(expr, val, path) { | |
if (expr) { | |
var x = expr.split(";"), loc = x.shift(); | |
x = x.join(";"); | |
if (val && val.hasOwnProperty(loc)) | |
P.trace(x, val[loc], path + ";" + loc); | |
else if (loc === "*") | |
P.walk(loc, x, val, path, function(m,l,x,v,p) { P.trace(m+";"+x,v,p); }); | |
else if (loc === "..") { | |
P.trace(x, val, path); | |
P.walk(loc, x, val, path, function(m,l,x,v,p) { typeof v[m] === "object" && P.trace("..;"+x,v[m],p+";"+m); }); | |
} | |
else if (/,/.test(loc)) { // [name1,name2,...] | |
for (var s=loc.split(/'?,'?/),i=0,n=s.length; i<n; i++) | |
P.trace(s[i]+";"+x, val, path); | |
} | |
else if (/^\(.*?\)$/.test(loc)) // [(expr)] | |
P.trace(P.eval(loc, val, path.substr(path.lastIndexOf(";")+1))+";"+x, val, path); | |
else if (/^\?\(.*?\)$/.test(loc)) // [?(expr)] | |
P.walk(loc, x, val, path, function(m,l,x,v,p) { if (P.eval(l.replace(/^\?\((.*?)\)$/,"$1"),v[m],m)) P.trace(m+";"+x,v,p); }); | |
else if (/^(-?[0-9]*):(-?[0-9]*):?([0-9]*)$/.test(loc)) // [start:end:step] phyton slice syntax | |
P.slice(loc, x, val, path); | |
} | |
else | |
P.store(path, val); | |
}, | |
walk: function(loc, expr, val, path, f) { | |
if (val instanceof Array) { | |
for (var i=0,n=val.length; i<n; i++) | |
if (i in val) | |
f(i,loc,expr,val,path); | |
} | |
else if (typeof val === "object") { | |
for (var m in val) | |
if (val.hasOwnProperty(m)) | |
f(m,loc,expr,val,path); | |
} | |
}, | |
slice: function(loc, expr, val, path) { | |
if (val instanceof Array) { | |
var len=val.length, start=0, end=len, step=1; | |
loc.replace(/^(-?[0-9]*):(-?[0-9]*):?(-?[0-9]*)$/g, function($0,$1,$2,$3){start=parseInt($1||start);end=parseInt($2||end);step=parseInt($3||step);}); | |
start = (start < 0) ? Math.max(0,start+len) : Math.min(len,start); | |
end = (end < 0) ? Math.max(0,end+len) : Math.min(len,end); | |
for (var i=start; i<end; i+=step) | |
P.trace(i+";"+expr, val, path); | |
} | |
}, | |
eval: function(x, _v, _vname) { | |
try { return $ && _v && eval(x.replace(/@/g, "_v")); } | |
catch(e) { throw new SyntaxError("jsonPath: " + e.message + ": " + x.replace(/@/g, "_v").replace(/\^/g, "_a")); } | |
} | |
}; | |
var $ = obj; | |
if (expr && obj && (P.resultType == "VALUE" || P.resultType == "PATH")) { | |
P.trace(P.normalize(expr).replace(/^\$;/,""), obj, "$"); | |
return P.result.length ? P.result : false; | |
} | |
} |