Add support for RSS feeds

go.mod

@@ -3,16 +3,25 @@ module code.betamike.com/mediocregopher/deadlinks
 go 1.20
 
 require (
-	code.betamike.com/mediocregopher/mediocre-go-lib v0.0.0-20231226160338-0b5bdf3dfb03 // indirect
+	code.betamike.com/mediocregopher/mediocre-go-lib v0.0.0-20231226160338-0b5bdf3dfb03
-	git.sr.ht/~adnano/go-gemini v0.2.3 // indirect
+	git.sr.ht/~adnano/go-gemini v0.2.3
+	github.com/mattn/go-sqlite3 v1.14.19
+	github.com/mmcdole/gofeed v1.2.1
+	github.com/rubenv/sql-migrate v1.6.0
+	github.com/stretchr/testify v1.8.4
+	golang.org/x/net v0.4.0
+)
+
+require (
+	github.com/PuerkitoBio/goquery v1.8.0 // indirect
+	github.com/andybalholm/cascadia v1.3.1 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/go-gorp/gorp/v3 v3.1.0 // indirect
-	github.com/mattn/go-sqlite3 v1.14.19 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/mmcdole/goxpp v1.1.0 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/rubenv/sql-migrate v1.6.0 // indirect
+	golang.org/x/text v0.5.0 // indirect
-	github.com/stretchr/objx v0.5.0 // indirect
-	github.com/stretchr/testify v1.8.4 // indirect
-	golang.org/x/net v0.0.0-20210119194325-5f4716e94777 // indirect
-	golang.org/x/text v0.3.3 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,36 +1,57 @@
-code.betamike.com/mediocregopher/mediocre-go-lib v0.0.0-20231226155808-e8376ef263a7 h1:Dm7oXBLmdPXVo8tPZzrmUvON6zXEdWxbGiO4chqrNHw=
-code.betamike.com/mediocregopher/mediocre-go-lib v0.0.0-20231226155808-e8376ef263a7/go.mod h1:GJhpoMNnN/OT6O9NmeQBV02yq9kQP8zPyY1IvsslHak=
 code.betamike.com/mediocregopher/mediocre-go-lib v0.0.0-20231226160338-0b5bdf3dfb03 h1:wJ6X1vc289RpHVGClD1P33yijPoNIdgCXbTn7DjVWYs=
 code.betamike.com/mediocregopher/mediocre-go-lib v0.0.0-20231226160338-0b5bdf3dfb03/go.mod h1:GJhpoMNnN/OT6O9NmeQBV02yq9kQP8zPyY1IvsslHak=
 git.sr.ht/~adnano/go-gemini v0.2.3 h1:oJ+Y0/mheZ4Vg0ABjtf5dlmvq1yoONStiaQvmWWkofc=
 git.sr.ht/~adnano/go-gemini v0.2.3/go.mod h1:hQ75Y0i5jSFL+FQ7AzWVAYr5LQsaFC7v3ZviNyj46dY=
+github.com/PuerkitoBio/goquery v1.8.0 h1:PJTF7AmFCFKk1N6V6jmKfrNH9tV5pNE6lZMkG0gta/U=
+github.com/PuerkitoBio/goquery v1.8.0/go.mod h1:ypIiRMtY7COPGk+I/YbZLbxsxn9g5ejnI2HSMtkjZvI=
+github.com/andybalholm/cascadia v1.3.1 h1:nhxRkql1kdYCc8Snf7D5/D3spOX+dBgjA6u8x004T2c=
+github.com/andybalholm/cascadia v1.3.1/go.mod h1:R4bJ1UQfqADjvDa4P6HZHLh/3OxWWEqc0Sk8XGwHqvA=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/go-gorp/gorp/v3 v3.1.0 h1:ItKF/Vbuj31dmV4jxA1qblpSwkl9g1typ24xoe70IGs=
 github.com/go-gorp/gorp/v3 v3.1.0/go.mod h1:dLEjIyyRNiXvNZ8PSmzpt1GsWAUK8kjVhEpjH8TixEw=
+github.com/go-sql-driver/mysql v1.6.0 h1:BCTh4TKNUYmOmMUcQ3IipzF5prigylS7XXjEkfCHuOE=
+github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
+github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
+github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
+github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
+github.com/lib/pq v1.10.7 h1:p7ZhMD+KsSRozJr34udlUrhboJwWAgCg34+/ZZNvZZw=
 github.com/mattn/go-sqlite3 v1.14.19 h1:fhGleo2h1p8tVChob4I9HpmVFIAkKGpiukdrgQbWfGI=
 github.com/mattn/go-sqlite3 v1.14.19/go.mod h1:2eHXhiwb8IkHr+BDWZGa96P6+rkvnG63S2DGjv9HUNg=
+github.com/mmcdole/gofeed v1.2.1 h1:tPbFN+mfOLcM1kDF1x2c/N68ChbdBatkppdzf/vDe1s=
+github.com/mmcdole/gofeed v1.2.1/go.mod h1:2wVInNpgmC85q16QTTuwbuKxtKkHLCDDtf0dCmnrNr4=
+github.com/mmcdole/goxpp v1.1.0 h1:WwslZNF7KNAXTFuzRtn/OKZxFLJAAyOA9w82mDz2ZGI=
+github.com/mmcdole/goxpp v1.1.0/go.mod h1:v+25+lT2ViuQ7mVxcncQ8ch1URund48oH+jhjiwEgS8=
+github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
+github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
+github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
+github.com/modern-go/reflect2 v1.0.2 h1:xBagoLtFs94CBntxluKeaWgTMpvLxC4ur3nMaC9Gz0M=
+github.com/modern-go/reflect2 v1.0.2/go.mod h1:yWuevngMOJpCy52FWWMvUC8ws7m/LJsjYzDa0/r8luk=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/poy/onpar v1.1.2 h1:QaNrNiZx0+Nar5dLgTVp5mXkyoVFIbepjyEoGSnhbAY=
+github.com/rogpeppe/go-internal v1.9.0 h1:73kH8U+JUqXU8lRuOHeVHaa/SZPifC7BkcraZVejAe8=
 github.com/rubenv/sql-migrate v1.6.0 h1:IZpcTlAx/VKXphWEpwWJ7BaMq05tYtE80zYz+8a5Il8=
 github.com/rubenv/sql-migrate v1.6.0/go.mod h1:m3ilnKP7sNb4eYkLsp6cGdPOl4OBcXM6rcbzU+Oqc5k=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
-github.com/stretchr/objx v0.5.0 h1:1zr/of2m5FGMsad5YfcqgdqdWrIhu+EBEJRhR1U7z/c=
-github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
-github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
-golang.org/x/net v0.0.0-20210119194325-5f4716e94777 h1:003p0dJM77cxMSyCPFphvZf/Y5/NXf5fzg6ufd1/Oew=
 golang.org/x/net v0.0.0-20210119194325-5f4716e94777/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.0.0-20210916014120-12bc252f5db8/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/net v0.4.0 h1:Q5QPcMlvfxFTAPV0+07Xz/MpK9NTXu2VDUuy0FeMfaU=
+golang.org/x/net v0.4.0/go.mod h1:MBQ8lrhLObU/6UmLb4fmbmk5OcyYmqtbGd/9yIeKjEE=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.5.0 h1:OLmvp0KP+FVG99Ct/qFiL/Fhk4zp4QQnZ7b2U+5piUM=
+golang.org/x/text v0.5.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

parser.go

@@ -8,6 +8,7 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/mmcdole/gofeed"
 	"golang.org/x/net/html"
 )
 
@@ -35,8 +36,9 @@ type parser struct {
 // Supported MIME types:
 // - text/gemtext
 // - text/html
-// - application/rss+xml (TODO)
+// - application/rss+xml
-// - application/atom+xml (TODO)
+// - application/atom+xml
+// - application/feed+json
 func NewParser() Parser {
 	return &parser{
 		brPool: sync.Pool{
@@ -129,9 +131,66 @@ func parseHTML(body *bufio.Reader) ([]URL, error) {
 	}
 }
 
+func parseFeed(body *bufio.Reader) ([]URL, error) {
+	feed, err := gofeed.NewParser().Parse(body)
+	if err != nil {
+		return nil, err
+	}
+
+	var (
+		urls []URL
+		errs []error
+	)
+
+	tryAppend := func(s string) {
+		if s == "" {
+			return
+		}
+
+		url, err := ParseURL(s)
+		if err != nil {
+			errs = append(errs, fmt.Errorf("parsing URL %q: %w", s, err))
+		} else {
+			urls = append(urls, url)
+		}
+	}
+
+	tryAppend(feed.Link)
+	tryAppend(feed.FeedLink)
+	for _, l := range feed.Links {
+		tryAppend(l)
+	}
+
+	if feed.Image != nil {
+		tryAppend(feed.Image.URL)
+	}
+
+	for _, item := range feed.Items {
+		tryAppend(item.Link)
+		for _, l := range item.Links {
+			tryAppend(l)
+		}
+
+		if item.Image != nil {
+			tryAppend(item.Image.URL)
+		}
+
+		for _, enc := range item.Enclosures {
+			if enc != nil {
+				tryAppend(enc.URL)
+			}
+		}
+	}
+
+	return urls, errors.Join(errs...)
+}
+
 var parsersByMimeType = map[string]func(*bufio.Reader) ([]URL, error){
-	"text/gemini": parseGemtext,
+	"text/gemini":           parseGemtext,
-	"text/html":   parseHTML,
+	"text/html":             parseHTML,
+	"application/rss+xml":   parseFeed,
+	"application/atom+xml":  parseFeed,
+	"application/feed+json": parseFeed,
 }
 
 func (p *parser) Parse(mimeType string, body io.Reader) ([]URL, error) {