lix-releng-staging/src/libexpr/value-to-json.cc
Eelco Dolstra c0a7b84748 nix path-info: Add --json flag
Also, factor out JSON generation from value-to-json.{cc,hh}, and
support producing indented JSON.
2016-08-29 17:29:24 +02:00

96 lines
2.4 KiB
C++

#include "value-to-json.hh"
#include "json.hh"
#include "eval-inline.hh"
#include "util.hh"
#include <cstdlib>
#include <iomanip>
namespace nix {
void printValueAsJSON(EvalState & state, bool strict,
Value & v, JSONPlaceholder & out, PathSet & context)
{
checkInterrupt();
if (strict) state.forceValue(v);
switch (v.type) {
case tInt:
out.write(v.integer);
break;
case tBool:
out.write(v.boolean);
break;
case tString:
copyContext(v, context);
out.write(v.string.s);
break;
case tPath:
out.write(state.copyPathToStore(context, v.path));
break;
case tNull:
out.write(nullptr);
break;
case tAttrs: {
Bindings::iterator i = v.attrs->find(state.sOutPath);
if (i == v.attrs->end()) {
auto obj(out.object());
StringSet names;
for (auto & j : *v.attrs)
names.insert(j.name);
for (auto & j : names) {
Attr & a(*v.attrs->find(state.symbols.create(j)));
auto placeholder(obj.placeholder(j));
printValueAsJSON(state, strict, *a.value, placeholder, context);
}
} else
printValueAsJSON(state, strict, *i->value, out, context);
break;
}
case tList1: case tList2: case tListN: {
auto list(out.list());
for (unsigned int n = 0; n < v.listSize(); ++n) {
auto placeholder(list.placeholder());
printValueAsJSON(state, strict, *v.listElems()[n], placeholder, context);
}
break;
}
case tExternal:
v.external->printValueAsJSON(state, strict, out, context);
break;
case tFloat:
out.write(v.fpoint);
break;
default:
throw TypeError(format("cannot convert %1% to JSON") % showType(v));
}
}
void printValueAsJSON(EvalState & state, bool strict,
Value & v, std::ostream & str, PathSet & context)
{
JSONPlaceholder out(str);
printValueAsJSON(state, strict, v, out, context);
}
void ExternalValueBase::printValueAsJSON(EvalState & state, bool strict,
JSONPlaceholder & out, PathSet & context) const
{
throw TypeError(format("cannot convert %1% to JSON") % showType());
}
}