Add subtractDays pp action to scraper (#1399)

pkg/scraper/mapped.go

@@ -393,6 +393,22 @@ func (p *postProcessParseDate) Apply(value string, q mappedQuery) string {
 	return parsedValue.Format(internalDateFormat)
 }
 
+type postProcessSubtractDays bool
+
+func (p *postProcessSubtractDays) Apply(value string, q mappedQuery) string {
+	const internalDateFormat = "2006-01-02"
+
+	i, err := strconv.Atoi(value)
+	if err != nil {
+		logger.Warnf("Error parsing day string %s: %s", value, err)
+		return value
+	}
+
+	dt := time.Now()
+	dt = dt.AddDate(0, 0, -i)
+	return dt.Format(internalDateFormat)
+}
+
 type postProcessReplace mappedRegexConfigs
 
 func (c *postProcessReplace) Apply(value string, q mappedQuery) string {
@@ -479,12 +495,13 @@ func (p *postProcessLbToKg) Apply(value string, q mappedQuery) string {
 }
 
 type mappedPostProcessAction struct {
-	ParseDate  string                   `yaml:"parseDate"`
+	ParseDate    string                   `yaml:"parseDate"`
-	Replace    mappedRegexConfigs       `yaml:"replace"`
+	SubtractDays bool                     `yaml:"subtractDays"`
-	SubScraper *mappedScraperAttrConfig `yaml:"subScraper"`
+	Replace      mappedRegexConfigs       `yaml:"replace"`
-	Map        map[string]string        `yaml:"map"`
+	SubScraper   *mappedScraperAttrConfig `yaml:"subScraper"`
-	FeetToCm   bool                     `yaml:"feetToCm"`
+	Map          map[string]string        `yaml:"map"`
-	LbToKg     bool                     `yaml:"lbToKg"`
+	FeetToCm     bool                     `yaml:"feetToCm"`
+	LbToKg       bool                     `yaml:"lbToKg"`
 }
 
 func (a mappedPostProcessAction) ToPostProcessAction() (postProcessAction, error) {
@@ -536,6 +553,14 @@ func (a mappedPostProcessAction) ToPostProcessAction() (postProcessAction, error
 		action := postProcessLbToKg(a.LbToKg)
 		ret = &action
 	}
+	if a.SubtractDays {
+		if found != "" {
+			return nil, fmt.Errorf("post-process actions must have a single field, found %s and %s", found, "subtractDays")
+		}
+		found = "subtractDays"
+		action := postProcessSubtractDays(a.SubtractDays)
+		ret = &action
+	}
 
 	if ret == nil {
 		return nil, errors.New("invalid post-process action")

ui/v2.5/src/components/Changelog/versions/v080.md

@@ -2,5 +2,6 @@
 * Added [DLNA server](/settings?tab=dlna). ([#1364](https://github.com/stashapp/stash/pull/1364))
 
 ### 🎨 Improvements
+* Add `subtractDays` post-process scraper action. ([#1399](https://github.com/stashapp/stash/pull/1399))
 * Skip scanning directories if path matches image and video exclude patterns. ([#1382](https://github.com/stashapp/stash/pull/1382))
 * Add button to remove studio stash ID. ([#1378](https://github.com/stashapp/stash/pull/1378))

ui/v2.5/src/docs/en/Scraping.md

@@ -372,6 +372,18 @@ Height and weight are extracted from the selected spans and converted to `cm` an
 
 * `parseDate`: if present, the value is the date format using go's reference date (2006-01-02). For example, if an example date was `14-Mar-2003`, then the date format would be `02-Jan-2006`. See the [time.Parse documentation](https://golang.org/pkg/time/#Parse) for details. When present, the scraper will convert the input string into a date, then convert it to the string format used by stash (`YYYY-MM-DD`). Strings "Today", "Yesterday" are matched (case insensitive) and converted by the scraper so you don't need to edit/replace them.
 
+* `subtractDays`: if set to `true` it subtracts the value in days from the current date and returns the resulting date in stash's date format.
+Example:
+```yaml
+Date:
+  selector: //strong[contains(text(),"Added:")]/following-sibling::text()
+  postProcess:
+    - replace:
+        - regex: (\d+)\sdays\sago.+
+          with: $1
+    - subtractDays: true
+```
+
 * `replace`: contains an array of sub-objects. Each sub-object must have a `regex` and `with` field. The `regex` field is the regex pattern to replace, and `with` is the string to replace it with. `$` is used to reference capture groups - `$1` is the first capture group, `$2` the second and so on. Replacements are performed in order of the array.
 
 Example: