unkinben
8696097a6a
pflag does not attach a space-separated value to a string flag that is grouped with a bool flag, so `node-lookup -R -pm k8s` parsed -p and left `k8s` as a stray positional, failing with "unknown command k8s". Only `-pm=k8s` or the un-grouped `-p -m k8s` worked, which is surprising. - Allow one positional argument (cobra.MaximumNArgs(1)) and fall back to it for the match value when -m is empty (matchValue()), so -pm/-im/-ipm <value> and a bare `-p <value>` all work. -m still wins when both are given. - Add matchValue unit tests. - Document the positional value and the pflag grouping quirk in AGENTS.md.
143 lines
6.3 KiB
Markdown
143 lines
6.3 KiB
Markdown
# AGENTS.md
|
|
|
|
## Project Overview
|
|
|
|
`node-lookup` is a Go CLI tool that queries a PuppetDB API to retrieve and filter node facts.
|
|
|
|
## Structure
|
|
|
|
```
|
|
main.go # entire application source
|
|
main_test.go # unit tests (mock PuppetDB via httptest, no live deps)
|
|
go.mod # Go module (module name: node-lookup)
|
|
go.sum # dependency checksums
|
|
Makefile # build / test / lint / completions / rpm / version-bump targets
|
|
packaging/nfpm.yaml # nfpm spec (envsubst-templated) for the RPM
|
|
scripts/build-rpm.sh # generates completions + packages the RPM with nfpm
|
|
.woodpecker/ # CI: build, test, pre-commit (PR) + release (tag)
|
|
dist/ # build output: binary, completions, RPM (not committed)
|
|
```
|
|
|
|
## Build
|
|
|
|
```bash
|
|
make build # -> dist/node-lookup (CGO disabled, static)
|
|
# or directly:
|
|
go build -o node-lookup ./...
|
|
```
|
|
|
|
Requires Go 1.21+. Dependencies: `github.com/spf13/cobra` (CLI), `gopkg.in/yaml.v3` (Ansible output).
|
|
|
|
## Packaging (RPM)
|
|
|
|
```bash
|
|
make rpm # build the binary + package it into dist/*.rpm via nfpm
|
|
```
|
|
|
|
`scripts/build-rpm.sh` generates bash/zsh/fish completions from the built binary
|
|
and bundles them alongside `/usr/bin/node-lookup`. On a `v*` tag the release
|
|
pipeline builds the RPM and `PUT`s it to the artifactapi `rpm-internal` repo.
|
|
|
|
## Shell completions
|
|
|
|
Cobra provides a `completion` subcommand:
|
|
|
|
```bash
|
|
node-lookup completion bash # or zsh / fish / powershell
|
|
```
|
|
|
|
The RPM installs completions to the standard system paths
|
|
(`/usr/share/bash-completion/completions/`, `/usr/share/zsh/site-functions/`,
|
|
`/usr/share/fish/vendor_completions.d/`), so they work automatically once
|
|
installed. To load ad-hoc in the current shell, e.g. zsh:
|
|
`source <(node-lookup completion zsh)`.
|
|
|
|
## Running the Tool
|
|
|
|
```bash
|
|
./node-lookup --help
|
|
./node-lookup -R # show all nodes with role fact
|
|
./node-lookup -n <hostname> # lookup a specific node
|
|
./node-lookup -F <fact_name> # filter by fact name
|
|
./node-lookup -R -m <value> # exact value match (-m)
|
|
./node-lookup -R -pm <value> # partial/regex match (-p -m combined)
|
|
./node-lookup -R -im <value> # inverse exact match (-i -m combined)
|
|
./node-lookup -R -ipm <value> # inverse partial match (-i -p -m combined)
|
|
./node-lookup -R -p <value> # value may also be given positionally
|
|
./node-lookup -R -1 # node names only
|
|
./node-lookup -R -2 # values only
|
|
./node-lookup -R -C # count occurrences
|
|
./node-lookup -R -A # output as Ansible YAML inventory
|
|
./node-lookup -j # output as JSON { host → { fact → value } }
|
|
./node-lookup --url http://host:8080/... # override PuppetDB URL for this invocation
|
|
echo -e "node1\nnode2" | ./node-lookup -R # pipe node names via stdin
|
|
```
|
|
|
|
## Configuration
|
|
|
|
Precedence (lowest → highest): **defaults < config file < env vars < `--url` flag**
|
|
|
|
### Config file
|
|
|
|
XDG location: `$XDG_CONFIG_HOME/node-lookup/config.yaml` (default: `~/.config/node-lookup/config.yaml`)
|
|
|
|
```yaml
|
|
puppetdb_url: http://puppetdbapi.service.consul:8080/pdb/query/v4/facts
|
|
role_fact: enc_role
|
|
```
|
|
|
|
Generate the default config file:
|
|
```bash
|
|
./node-lookup config init
|
|
```
|
|
|
|
Show the active configuration (after all overrides applied):
|
|
```bash
|
|
./node-lookup config show
|
|
```
|
|
|
|
### Environment variables
|
|
|
|
| Variable | Config key | Description |
|
|
|---|---|---|
|
|
| `NODE_LOOKUP_URL` | `puppetdb_url` | PuppetDB facts endpoint |
|
|
| `NODE_LOOKUP_ROLE_FACT` | `role_fact` | Fact name used by `-R` flag |
|
|
|
|
### CLI flag
|
|
|
|
`--url <url>` overrides the PuppetDB URL for a single invocation (highest precedence).
|
|
|
|
## Code Patterns
|
|
|
|
- **`loadConfig()`**: reads config file → applies env vars → returns `config` struct. Called once at startup in `main()`.
|
|
- **`buildQuery()`**: returns a PuppetDB PQL-compatible JSON array string. Uses `roleFact` from config (not hardcoded). Match modifiers: `-p` (partial/regex, uses `~` op), `-i` (inverse, wraps with `not`), composable.
|
|
- **Match value / `matchValue()`**: the value to match comes from `-m/--match` or, if that is empty, an optional positional argument. The positional fallback exists because pflag does not attach a space-separated value to a string flag grouped with a bool flag, so in `-pm k8s` the `k8s` arrives as a positional. `-m` still wins when both are given.
|
|
- **`queryPuppetDB(url, query)`**: takes the URL as a parameter — never reads globals.
|
|
- **`processResults()`**: iterates facts, returns sorted `"certname value"` strings. JSON string values are unquoted; other JSON types rendered as compact JSON.
|
|
- **Output modes**: JSON (`-j`), count (`-C`), Ansible YAML (`-A`), node-only (`-1`), value-only (`-2`), default (node + value).
|
|
- **Stdin support**: `stdinReader()` reads node names from stdin only when it is a real pipe/redirect carrying data (and no `-n` given). Terminals, `/dev/null`, and empty/closed pipes fall through to a normal query — so running without a TTY (e.g. invoked by an agent or CI) behaves like an interactive run instead of consuming empty input.
|
|
- **SIGPIPE handling**: `signal.Ignore(syscall.SIGPIPE)` so pipes to `head` etc. work cleanly.
|
|
|
|
## CLI Framework
|
|
|
|
Uses [Cobra](https://github.com/spf13/cobra). Root command is the query command. `config` is a subcommand with `init` and `show` sub-subcommands.
|
|
|
|
## Testing
|
|
|
|
```bash
|
|
make test # go test -v -race ./...
|
|
```
|
|
|
|
`main_test.go` covers query construction (all `-m`/`-p`/`-i` combinations), value
|
|
rendering, result processing/counting, config precedence (defaults < file < env),
|
|
`writeDefaultConfig`, the `stdinReader` no-TTY behavior, and every `run()` output
|
|
mode (default, `-1`, `-2`, `-C`, `-j`, `-A`, `-a`). PuppetDB is stubbed with
|
|
`httptest` — no live Consul/PuppetDB access is required.
|
|
|
|
## Gotchas
|
|
|
|
- `-1`, `-2`, `-C`, and `-A` all require `-R` or `-F`; the tool exits with an error otherwise.
|
|
- `-C` (count) with stdin reads all lines as pre-fetched `"node value"` output for counting — it does **not** query PuppetDB per line.
|
|
- JSON output (`-j`) builds `{ hostname: { factname: value } }` where the fact key is the `-F` value, the `role_fact` config value (if `-R`), or `"value"` as fallback.
|
|
- `config init` fails if the config file already exists (will not overwrite).
|