nak/req.go

package main

import (
	"encoding/json"
	"fmt"
	"strings"

	"github.com/nbd-wtf/go-nostr"
	"github.com/urfave/cli/v2"
)

const CATEGORY_FILTER_ATTRIBUTES = "FILTER ATTRIBUTES"

var req = &cli.Command{
	Name:  "req",
	Usage: "generates an encoded REQ message to be sent to a relay",
	Description: `outputs a NIP-01 Nostr filter. when a relay is not given, will print the filter, otherwise will connect to the given relay and send the filter.

example usage (with 'nostcat'):
		nak req -k 1 -a 3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d | nostcat wss://nos.lol

standalone:
		nak req -k 1 wss://nos.lol`,
	Flags: []cli.Flag{
		&cli.StringSliceFlag{
			Name:     "author",
			Aliases:  []string{"a"},
			Usage:    "only accept events from these authors (pubkey as hex)",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.StringSliceFlag{
			Name:     "id",
			Aliases:  []string{"i"},
			Usage:    "only accept events with these ids (hex)",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.IntSliceFlag{
			Name:     "kind",
			Aliases:  []string{"k"},
			Usage:    "only accept events with these kind numbers",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.StringSliceFlag{
			Name:     "tag",
			Aliases:  []string{"t"},
			Usage:    "takes a tag like -t e=<id>, only accept events with these tags",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.StringSliceFlag{
			Name:     "e",
			Usage:    "shortcut for --tag e=<value>",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.StringSliceFlag{
			Name:     "p",
			Usage:    "shortcut for --tag p=<value>",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.IntFlag{
			Name:     "since",
			Aliases:  []string{"s"},
			Usage:    "only accept events newer than this (unix timestamp)",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.IntFlag{
			Name:     "until",
			Aliases:  []string{"u"},
			Usage:    "only accept events older than this (unix timestamp)",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.IntFlag{
			Name:     "limit",
			Aliases:  []string{"l"},
			Usage:    "only accept up to this number of events",
			Category: CATEGORY_FILTER_ATTRIBUTES,
		},
		&cli.BoolFlag{
			Name:  "bare",
			Usage: "when printing the filter, print just the filter, not enveloped in a [\"REQ\", ...] array",
		},
		&cli.BoolFlag{
			Name:        "stream",
			Usage:       "keep the subscription open, printing all events as they are returned",
			DefaultText: "false, will close on EOSE",
		},
	},
	ArgsUsage: "[relay...]",
	Action: func(c *cli.Context) error {
		filter := nostr.Filter{}

		if authors := c.StringSlice("author"); len(authors) > 0 {
			filter.Authors = authors
		}
		if ids := c.StringSlice("id"); len(ids) > 0 {
			filter.IDs = ids
		}
		if kinds := c.IntSlice("kind"); len(kinds) > 0 {
			filter.Kinds = kinds
		}

		tags := make([][]string, 0, 5)
		for _, tagFlag := range c.StringSlice("tag") {
			spl := strings.Split(tagFlag, "=")
			if len(spl) == 2 && len(spl[0]) == 1 {
				tags = append(tags, spl)
			} else {
				return fmt.Errorf("invalid --tag '%s'", tagFlag)
			}
		}
		for _, etag := range c.StringSlice("e") {
			tags = append(tags, []string{"e", etag})
		}
		for _, ptag := range c.StringSlice("p") {
			tags = append(tags, []string{"p", ptag})
		}
		if len(tags) > 0 {
			filter.Tags = make(nostr.TagMap)
			for _, tag := range tags {
				if _, ok := filter.Tags[tag[0]]; !ok {
					filter.Tags[tag[0]] = make([]string, 0, 3)
				}
				filter.Tags[tag[0]] = append(filter.Tags[tag[0]], tag[1])
			}
		}

		if since := c.Int("since"); since != 0 {
			ts := nostr.Timestamp(since)
			filter.Since = &ts
		}
		if until := c.Int("until"); until != 0 {
			ts := nostr.Timestamp(until)
			filter.Until = &ts
		}
		if limit := c.Int("limit"); limit != 0 {
			filter.Limit = limit
		}

		relays := c.Args().Slice()
		if len(relays) > 0 {
			pool := nostr.NewSimplePool(c.Context)
			fn := pool.SubManyEose
			if c.Bool("stream") {
				fn = pool.SubMany
			}
			for evt := range fn(c.Context, relays, nostr.Filters{filter}) {
				fmt.Println(evt)
			}
		} else {
			// no relays given, will just print the filter
			var result string
			if c.Bool("bare") {
				result = filter.String()
			} else {
				j, _ := json.Marshal([]any{"REQ", "nak", filter})
				result = string(j)
			}

			fmt.Println(result)
		}

		return nil
	},
}