node-lookup/AGENTS.md

AGENTS.md

Project Overview

This repo ships four related Puppet tools in one RPM:

• node-lookup — queries the PuppetDB API to retrieve and filter node facts.
• pburl — prints the Puppetboard node-page URL for each host (reads hosts from args or piped node-lookup output). Output: <host> <url>.
• pblastreport — prints each host's last Puppet report time and its Puppetboard URL. Output: <host>\t<time>\t<url>. Supports --relative/-r (relative age) and --timezone/-z <IANA> (default: local timezone).
• pdbmux — a long-running HTTP daemon that presents a single merged PuppetDB v4 query surface over the old (Consul) and new (k8s) PuppetDBs during the VM→k8s migration. Merges /pdb/query/v4/{nodes,facts}, transparently proxies other v4 paths to the primary, and exposes /healthz. See README.md for full config/merge semantics.

node-lookup is the module root; pburl, pblastreport and pdbmux live under cmd/. The three CLI tools share the internal/puppet package (config, PuppetDB nodes queries, Puppetboard URL construction, stdin host reading); pdbmux is self-contained (its own config + HTTP server).

Structure

main.go                       # node-lookup CLI source (module root, package main)
main_test.go                  # node-lookup unit tests (mock PuppetDB via httptest)
cmd/pburl/main.go             # pburl CLI
cmd/pblastreport/main.go      # pblastreport CLI (report.go: report-time formatting)
cmd/pdbmux/                   # pdbmux daemon: main.go, config.go, merge.go, server.go
internal/puppet/              # shared: config, puppetdb nodes query, board URLs, stdin
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 (all 4 binaries)
packaging/pdbmux.service # systemd unit for the pdbmux daemon
scripts/build-rpm.sh # generates completions + packages the RPM with nfpm
.woodpecker/        # CI: build, test, pre-commit (PR) + release (tag)
dist/               # build output: binaries, completions, RPM (not committed)

Every binary is a separate main package, so make build builds each with its own -o (a single go build ./... can't emit multiple mains to one file).

Build

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)

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 PUTs it to the artifactapi rpm-internal repo.

Shell completions

Cobra provides a completion subcommand:

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

./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 -jF ipaddress,enc_role      # several facts at once (comma-separated)
./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 (queried facts become host vars)
./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

Companion tools

node-lookup -R | pburl                    # <host> <puppetboard-url> per line
pburl host1 host2                          # hosts as args instead of stdin

node-lookup -R | pblastreport              # <host>  <last-report-time>  <url>
pblastreport -r host1                       # relative age (e.g. "3h ago")
pblastreport -z Asia/Singapore host1        # render the time in a specific IANA tz

Both read hostnames from arguments or the first field of each piped line (so any node-lookup output mode works), de-duplicate, and share node-lookup's config file / env vars. pblastreport reads report_timestamp from the PuppetDB v4 nodes endpoint (derived from the configured facts URL).

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)

puppetdb_url: http://puppetdbapi.service.consul:8080/pdb/query/v4/facts
role_fact: enc_role
puppetboard_url: https://puppetboard.k8s.syd1.au.unkin.net  # used by pburl / pblastreport

Generate the default config file:

./node-lookup config init

Show the active configuration (after all overrides applied):

./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
NODE_LOOKUP_PUPPETBOARD_URL	puppetboard_url	Puppetboard base URL (pburl / pblastreport)

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.
• Multiple facts: -F accepts a comma-separated list (ipaddress,enc_role). splitFactNames()/nameFilter() turn several names into an or over ["=","name",<n>] clauses; JSON output keys each value by the fact's real name so all requested facts appear per host.
• 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). -j and -A share factsByHost(), so both attach the queried fact(s) per host — as an object under the host (-j) or as inventory host vars (-A).
• 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. Root command is the query command. config is a subcommand with init and show sub-subcommands.

Testing

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 } } keyed by each result's actual fact name (so -F ipaddress,enc_role yields both per host); it falls back to the -F value, the role_fact config value (if -R), or "value" only when a result carries no name.
• config init fails if the config file already exists (will not overwrite).