Commit `bf87ba9fc5`

bf87ba9fc5853883feb74607b3488d17cab01e98

parent: cf823b1736

Verified · cmc

cmc <hello@cleberg.net> · 2026-09-11 02:44 UTC

Add the api-cache config block and a shared lifetime parser

Ref #8

Layout: unified · split

SETUP.md +11

 Time units:
 * `i` — minutes
 * `h` — hours
+* `d` — days
 * `w` — weeks
 * `m` — months
 * `y` — years
   * `lifetime` — Cached file life time, requires numeric value, followed by multiplicative suffix (see Time Units for details)
   * `max-size` — Maximum file size in megabytes
   * `update-interval` — Automatic rotation interval
+* `api-cache` — In-memory cache of DeviantArt API responses. Every page,
+  feed poll and API call that asks DeviantArt the same question within the
+  TTL is answered from memory, and concurrent requests for one thing make
+  one upstream call. On by default; DeviantArt bans egress IPs that ask too
+  often, so leave it on unless you are debugging.
+  * `enabled` — boolean, default true
+  * `max-size` — megabytes of response bodies to hold, default 64. Least
+    recently used entries are dropped past this.
+  * `ttl` — how long a response is reused, in the time units above. Default
+    `5i`.
 * `static-path` — This setting determines path to static, which will be copied to RAM when SkunkyArt is started. Useless if you're use binary compiled with 'embed' tag.
 * `download-proxy` — Outbound proxy used when fetching media from DeviantArt's
   CDN. Leave empty (`""`) unless you actually run a proxy: if this points at

app/config.go +73 −33

	@@ -2,6 +2,7 @@ package app
2		2
3	import (	3	import (
4	"encoding/json"	4	"encoding/json"
		5	"errors"
5	"os"	6	"os"
6	"regexp"	7	"regexp"
7	"skunkyart/static"	8	"skunkyart/static"
	@@ -27,19 +28,26 @@ type cacheConfig struct {
27	UpdateInterval int64 `json:"update-interval"`	28	UpdateInterval int64 `json:"update-interval"`
28	}	29	}
29		30
		31	type apiCacheConfig struct {
		32	Enabled bool `json:"enabled"`
		33	MaxSize int64 `json:"max-size"`
		34	TTL string `json:"ttl"`
		35	}
		36
30	type config struct {	37	type config struct {
31	cfg string	38	cfg string
32	Listen string `json:"listen"`	39	Listen string `json:"listen"`
33	URI string `json:"uri"`	40	URI string `json:"uri"`
34	Cache cacheConfig `json:"cache"`	41	Cache cacheConfig `json:"cache"`
35	Proxy bool `json:"proxy"`	42	APICache apiCacheConfig `json:"api-cache"`
36	Nsfw bool `json:"nsfw"`	43	Proxy bool `json:"proxy"`
37	HideAI bool `json:"hide-ai"`	44	Nsfw bool `json:"nsfw"`
38	Theme string `json:"theme"`	45	HideAI bool `json:"hide-ai"`
39	Language string `json:"language"`	46	Theme string `json:"theme"`
40	UserAgent string `json:"user-agent"`	47	Language string `json:"language"`
41	DownloadProxy string `json:"download-proxy"`	48	UserAgent string `json:"user-agent"`
42	StaticPath string `json:"static-path"`	49	DownloadProxy string `json:"download-proxy"`
		50	StaticPath string `json:"static-path"`
43	}	51	}
44		52
45	// CFG is the running instance's configuration, holding the defaults below until	53	// CFG is the running instance's configuration, holding the defaults below until
	@@ -55,6 +63,11 @@ var CFG = config{
55	Path: "cache",	63	Path: "cache",
56	UpdateInterval: 1,	64	UpdateInterval: 1,
57	},	65	},
		66	APICache: apiCacheConfig{
		67	Enabled: true,
		68	MaxSize: 64,
		69	TTL: "5i",
		70	},
58	StaticPath: "static",	71	StaticPath: "static",
59	UserAgent: "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36",	72	UserAgent: "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36",
60	Proxy: true,	73	Proxy: true,
	@@ -63,6 +76,43 @@ var CFG = config{
63		76
64	var lifetimeParsed int64	77	var lifetimeParsed int64
65		78
		79	// apiCacheTTL is api-cache.ttl parsed, set by ExecuteConfig.
		80	var apiCacheTTL time.Duration
		81
		82	// parseLifetime reads a duration in the config's unit syntax: a number
		83	// followed by i (minutes), h (hours), d (days), w (weeks), m (30-day
		84	// months) or y (360-day years).
		85	func parseLifetime(s string) (time.Duration, error) {
		86	if s == "" {
		87	return 0, errors.New("empty lifetime")
		88	}
		89	numstr := regexp.MustCompile("[0-9]+").FindAllString(s, -1)
		90	if len(numstr) == 0 {
		91	return 0, errors.New("lifetime has no number: " + s)
		92	}
		93	num, _ := strconv.Atoi(numstr[len(numstr)-1])
		94
		95	day := 24 * time.Hour
		96	var unit time.Duration
		97	switch s[len(s)-1:] {
		98	case "i":
		99	unit = time.Minute
		100	case "h":
		101	unit = time.Hour
		102	case "d":
		103	unit = day
		104	case "w":
		105	unit = 7 * day
		106	case "m":
		107	unit = 30 * day
		108	case "y":
		109	unit = 360 * day
		110	default:
		111	return 0, errors.New("invalid unit specified: " + s[len(s)-1:])
		112	}
		113	return unit * time.Duration(num), nil
		114	}
		115
66	// checkCacheWritable creates the cache directory if it is missing and confirms	116	// checkCacheWritable creates the cache directory if it is missing and confirms
67	// this process can actually write into it, returning the error that a real cache	117	// this process can actually write into it, returning the error that a real cache
68	// write would hit.	118	// write would hit.
	@@ -104,29 +154,11 @@ func ExecuteConfig() {
104	}	154	}
105		155
106	if CFG.Cache.Lifetime != "" {	156	if CFG.Cache.Lifetime != "" {
107	var duration int64	157	d, err := parseLifetime(CFG.Cache.Lifetime)
108	day := 24 * time.Hour.Milliseconds()	158	if err != nil {
109	numstr := regexp.MustCompile("[0-9]+").FindAllString(CFG.Cache.Lifetime, -1)	159	exit("config: cache.lifetime: "+err.Error(), 1)
110	num, _ := strconv.Atoi(numstr[len(numstr)-1])
111
112	switch unit := CFG.Cache.Lifetime[len(CFG.Cache.Lifetime)-1:]; unit {
113	case "i":
114	duration = time.Minute.Milliseconds()
115	case "h":
116	duration = time.Hour.Milliseconds()
117	case "d":
118	duration = day
119	case "w":
120	duration = day * 7
121	case "m":
122	duration = day * 30
123	case "y":
124	duration = day * 360
125	default:
126	exit("Invalid unit specified: "+unit, 1)
127	}	160	}
128		161	lifetimeParsed = d.Milliseconds()
129	lifetimeParsed = duration * int64(num)
130	}	162	}
131	// max-size is documented in megabytes. This was 1024^2, which in Go is	163	// max-size is documented in megabytes. This was 1024^2, which in Go is
132	// XOR (1026), not exponentiation — so the cap was ~1000x too small.	164	// XOR (1026), not exponentiation — so the cap was ~1000x too small.
	@@ -152,6 +184,14 @@ func ExecuteConfig() {
152	exit("config: theme must be one of auto, dark, light; got "+CFG.Theme, 1)	184	exit("config: theme must be one of auto, dark, light; got "+CFG.Theme, 1)
153	}	185	}
154		186
		187	if CFG.APICache.Enabled {
		188	d, err := parseLifetime(CFG.APICache.TTL)
		189	if err != nil {
		190	exit("config: api-cache.ttl: "+err.Error(), 1)
		191	}
		192	apiCacheTTL = d
		193	}
		194
155	static.StaticPath = CFG.StaticPath	195	static.StaticPath = CFG.StaticPath
156	devianter.UserAgent = CFG.UserAgent	196	devianter.UserAgent = CFG.UserAgent
157	}	197	}

app/config_test.go added +38

@@ -0,0 +1,38 @@
	1	package app
	2
	3	import (
	4	"testing"
	5	"time"
	6	)
	7
	8	func TestParseLifetimeUnits(t *testing.T) {
	9	cases := map[string]time.Duration{
	10	"5i": 5 * time.Minute,
	11	"2h": 2 * time.Hour,
	12	"3d": 72 * time.Hour,
	13	"1w": 7 * 24 * time.Hour,
	14	"1m": 30 * 24 * time.Hour,
	15	"1y": 360 * 24 * time.Hour,
	16	"12i": 12 * time.Minute,
	17	}
	18	for in, want := range cases {
	19	got, err := parseLifetime(in)
	20	if err != nil \|\| got != want {
	21	t.Errorf("parseLifetime(%q) = %v, %v; want %v", in, got, err, want)
	22	}
	23	}
	24	}
	25
	26	func TestParseLifetimeRejectsBadInput(t *testing.T) {
	27	for _, in := range []string{"", "5", "5x", "h"} {
	28	if _, err := parseLifetime(in); err == nil {
	29	t.Errorf("parseLifetime(%q) accepted, want an error", in)
	30	}
	31	}
	32	}
	33
	34	func TestAPICacheDefaults(t *testing.T) {
	35	if !CFG.APICache.Enabled \|\| CFG.APICache.MaxSize != 64 \|\| CFG.APICache.TTL != "5i" {
	36	t.Errorf("defaults are %+v, want enabled, 64 MB, 5i", CFG.APICache)
	37	}
	38	}

config.example.json +5

         "memcache": false,
         "update-interval": 5
     },
+    "api-cache": {
+        "enabled": true,
+        "max-size": 64,
+        "ttl": "5i"
+    },
     "static-path": "static",
     "download-proxy": "",
     "user-agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36",

Commit bf87ba9fc5

Commit `bf87ba9fc5`