This documents the outcome of the change in
https://github.com/NixOS/nix/issues/454:
> We can also automatically add parentheses in the generated
> `buildInputs`, so you can type `nix-shell -p "expr"`
> instead of `"(expr").
With this patch, and this file I called `log.py`:
#!/usr/bin/env nix-shell
#!nix-shell -i python3 -p python3 --pure
import sys
from pprint import pprint
stack = []
timestack = []
for line in open(sys.argv[1]):
components = line.strip().split(" ", 2)
if components[0] != "function-trace":
continue
direction = components[1]
components = components[2].rsplit(" ", 2)
loc = components[0]
_at = components[1]
time = int(components[2])
if direction == "entered":
stack.append(loc)
timestack.append(time)
elif direction == "exited":
dur = time - timestack.pop()
vst = ";".join(stack)
print(f"{vst} {dur}")
stack.pop()
and:
nix-instantiate --trace-function-calls -vvvv ../nixpkgs/pkgs/top-level/release.nix -A unstable > log.matthewbauer 2>&1
./log.py ./log.matthewbauer > log.matthewbauer.folded
flamegraph.pl --title matthewbauer-post-pr log.matthewbauer.folded > log.matthewbauer.folded.svg
I can make flame graphs like: http://gsc.io/log.matthewbauer.folded.svg
---
Includes test cases around function call failures and tryEval. Uses
RAII so the finish is always called at the end of the function.
Make curl's low speed limit configurable via stalled-download-timeout.
Before, this limit was five minutes without receiving a single byte.
This is much too long as if the remote end may not have even
acknowledged the HTTP request.
Passing `--post-build-hook /foo/bar` to a nix-* command will cause
`/foo/bar` to be executed after each build with the following
environment variables set:
DRV_PATH=/nix/store/drv-that-has-been-built.drv
OUT_PATHS=/nix/store/...build /nix/store/...build-bin /nix/store/...build-dev
This can be useful in particular to upload all the builded artifacts to
the cache (including the ones that don't appear in the runtime closure
of the final derivation or are built because of IFD).
This new feature prints the stderr/stdout output to the `nix-build`
and `nix build` client, and the output is printed in a Nix 2
compatible format:
[nix]$ ./inst/bin/nix-build ./test.nix
these derivations will be built:
/nix/store/ishzj9ni17xq4hgrjvlyjkfvm00b0ch9-my-example-derivation.drv
building '/nix/store/ishzj9ni17xq4hgrjvlyjkfvm00b0ch9-my-example-derivation.drv'...
hello!
bye!
running post-build-hook '/home/grahamc/projects/github.com/NixOS/nix/post-hook.sh'...
post-build-hook: + sleep 1
post-build-hook: + echo 'Signing paths' /nix/store/qr213vjmibrqwnyp5fw678y7whbkqyny-my-example-derivation
post-build-hook: Signing paths /nix/store/qr213vjmibrqwnyp5fw678y7whbkqyny-my-example-derivation
post-build-hook: + sleep 1
post-build-hook: + echo 'Uploading paths' /nix/store/qr213vjmibrqwnyp5fw678y7whbkqyny-my-example-derivation
post-build-hook: Uploading paths /nix/store/qr213vjmibrqwnyp5fw678y7whbkqyny-my-example-derivation
post-build-hook: + sleep 1
post-build-hook: + printf 'very important stuff'
/nix/store/qr213vjmibrqwnyp5fw678y7whbkqyny-my-example-derivation
[nix-shell:~/projects/github.com/NixOS/nix]$ ./inst/bin/nix build -L -f ./test.nix
my-example-derivation> hello!
my-example-derivation> bye!
my-example-derivation (post)> + sleep 1
my-example-derivation (post)> + echo 'Signing paths' /nix/store/c263gzj2kb2609mz8wrbmh53l14wzmfs-my-example-derivation
my-example-derivation (post)> Signing paths /nix/store/c263gzj2kb2609mz8wrbmh53l14wzmfs-my-example-derivation
my-example-derivation (post)> + sleep 1
my-example-derivation (post)> + echo 'Uploading paths' /nix/store/c263gzj2kb2609mz8wrbmh53l14wzmfs-my-example-derivation
my-example-derivation (post)> Uploading paths /nix/store/c263gzj2kb2609mz8wrbmh53l14wzmfs-my-example-derivation
my-example-derivation (post)> + sleep 1
my-example-derivation (post)> + printf 'very important stuff'
[1 built, 0.0 MiB DL]
Co-authored-by: Graham Christensen <graham@grahamc.com>
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
Inside a derivation, exportReferencesGraph already provides a way to
dump the Nix database for a specific closure. On the command line,
--dump-db gave us the same information, but only for the entire Nix
database at once.
With this change, one can now pass a list of paths to --dump-db to get
the Nix database dumped for just those paths. (The user is responsible
for ensuring this is a closure, like for --export).
Among other things, this is useful for deploying a closure to a new
host without using --import/--export; one can use tar to transfer the
store paths, and --dump-db/--load-db to transfer the validity
information. This is useful if the new host doesn't actually have Nix
yet, and the closure that is being deployed itself contains Nix.
- The instructions for using nix-shell as an interpreter has a Haskell script
example that doesn't work on more recent versions of Nix. Update the
instructions with a working command
This prints the references graph of the store paths in the graphML
format [1]. The graphML format is supported by several graph tools
such as the Python Networkx library or the Apache Thinkerpop project.
[1] http://graphml.graphdrawing.org
