diff options
| -rw-r--r-- | doc/manual/command-ref/nix-prefetch-url.xml | 1 | ||||
| -rw-r--r-- | src/nix-prefetch-url/nix-prefetch-url.cc | 40 |
2 files changed, 37 insertions, 4 deletions
diff --git a/doc/manual/command-ref/nix-prefetch-url.xml b/doc/manual/command-ref/nix-prefetch-url.xml index 0f24bef39abf..9cbaa42a1b1f 100644 --- a/doc/manual/command-ref/nix-prefetch-url.xml +++ b/doc/manual/command-ref/nix-prefetch-url.xml @@ -20,6 +20,7 @@ <cmdsynopsis> <command>nix-prefetch-url</command> <arg><option>--type</option> <replaceable>hashAlgo</replaceable></arg> + <arg><option>--print-path</option></arg> <arg choice='plain'><replaceable>url</replaceable></arg> <arg><replaceable>hash</replaceable></arg> </cmdsynopsis> diff --git a/src/nix-prefetch-url/nix-prefetch-url.cc b/src/nix-prefetch-url/nix-prefetch-url.cc index cb6078fca1c7..112d303e0c16 100644 --- a/src/nix-prefetch-url/nix-prefetch-url.cc +++ b/src/nix-prefetch-url/nix-prefetch-url.cc @@ -5,6 +5,7 @@ #include "eval.hh" #include "eval-inline.hh" #include "common-opts.hh" +#include "attr-path.hh" #include <iostream> @@ -49,6 +50,9 @@ int main(int argc, char * * argv) std::vector<string> args; Strings searchPath; bool printPath = getEnv("PRINT_PATH") != ""; + bool fromExpr = false; + string attrPath; + std::map<string, string> autoArgs_; parseCmdLine(argc, argv, [&](Strings::iterator & arg, const Strings::iterator & end) { if (*arg == "--help") @@ -63,6 +67,12 @@ int main(int argc, char * * argv) } else if (*arg == "--print-path") printPath = true; + else if (*arg == "--attr" || *arg == "-A") { + fromExpr = true; + attrPath = getArg(*arg, arg, end); + } + else if (parseAutoArgs(arg, end, autoArgs_)) + ; else if (parseSearchPathArg(arg, end, searchPath)) ; else if (*arg != "" && arg->at(0) == '-') @@ -72,15 +82,37 @@ int main(int argc, char * * argv) return true; }); - if (args.size() < 1 || args.size() > 2) - throw UsageError("nix-prefetch-url expects one argument"); + if (args.size() > 2) + throw UsageError("too many arguments"); store = openStore(); - EvalState state(searchPath); + Bindings & autoArgs(*evalAutoArgs(state, autoArgs_)); + + /* If -A is given, get the URI from the specified Nix + expression. */ + string uri; + if (!fromExpr) { + if (args.empty()) + throw UsageError("you must specify a URI"); + uri = args[0]; + } else { + Path path = resolveExprPath(lookupFileArg(state, args.empty() ? "." : args[0])); + Value vRoot; + state.evalFile(path, vRoot); + Value & v(*findAlongAttrPath(state, attrPath, autoArgs, vRoot)); + state.forceAttrs(v); + auto urls = v.attrs->find(state.symbols.create("urls")); + if (urls == v.attrs->end()) + throw Error("attribute set does not contain a ‘urls’ attribute"); + state.forceList(*urls->value); + if (urls->value->listSize() < 1) + throw Error("‘urls’ list is empty"); + uri = state.forceString(*urls->value->listElems()[0]); + } + /* Figure out a name in the Nix store. */ - auto uri = args[0]; auto name = baseNameOf(uri); if (name.empty()) throw Error(format("cannot figure out file name for ‘%1%’") % uri); |