fix "modifer" -> "modifier" typo everywhere

proxychain/responsemodifiers/block_element_removal.go

@@ -0,0 +1,42 @@
+package responsemodifiers
+
+import (
+	_ "embed"
+	"strings"
+
+	"ladder/proxychain"
+	"ladder/proxychain/responsemodifiers/rewriters"
+)
+
+//go:embed block_element_removal.js
+var blockElementRemoval string
+
+// BlockElementRemoval prevents paywall javascript from removing a
+// particular element by detecting the removal, then immediately reinserting it.
+// This is useful when a page will return a "fake" 404, after flashing the content briefly.
+// If the /outline/ API works, but the regular API doesn't, try this modifier.
+func BlockElementRemoval(cssSelector string) proxychain.ResponseModification {
+	return func(chain *proxychain.ProxyChain) error {
+		// don't add rewriter if it's not even html
+		ct := chain.Response.Header.Get("content-type")
+		if !strings.HasPrefix(ct, "text/html") {
+			return nil
+		}
+
+		params := map[string]string{
+			// ie: "div.article-content"
+			"{{CSS_SELECTOR}}": cssSelector,
+		}
+
+		rr := rewriters.NewScriptInjectorRewriterWithParams(
+			blockElementRemoval,
+			rewriters.BeforeDOMContentLoaded,
+			params,
+		)
+
+		htmlRewriter := rewriters.NewHTMLRewriter(chain.Response.Body, rr)
+		chain.Response.Body = htmlRewriter
+
+		return nil
+	}
+}