Decrease amount of requests send to Maven repos (#57765)

packages/react-native/scripts/cocoapods/rncore.rb

@@ -371,7 +371,7 @@ def self.nightly_tarball_url(version, configuration, dsyms = false)
         artefact_name = "reactnative-core-#{dsyms ? "dSYM-" : ""}#{configuration ? configuration : "debug"}.tar.gz"
         xml_url = "https://central.sonatype.com/repository/maven-snapshots/com/facebook/react/#{artefact_coordinate}/#{version}-SNAPSHOT/maven-metadata.xml"
 
-        response = Net::HTTP.get_response(URI(xml_url))
+        response = ReactNativePodsUtils.memoized_get_response(xml_url)
         if response.is_a?(Net::HTTPSuccess)
           xml = REXML::Document.new(response.body)
           timestamp = xml.elements['metadata/versioning/snapshot/timestamp'].text
@@ -476,11 +476,11 @@ def self.artifacts_dir()
         return File.join(Pod::Config.instance.project_pods_root, "ReactNativeCore-artifacts")
     end
 
-    # This function checks that ReactNativeCore artifact exists on the maven repo
+    # This function checks that ReactNativeCore artifact exists on the maven repo.
+    # The probe is memoized, so repeated podspec evaluations in one `pod install`
+    # don't re-request the same URL.
     def self.artifact_exists(tarball_url)
-        # -L is used to follow redirects, useful for the nightlies
-        # I also needed to wrap the url in quotes to avoid escaping & and ?.
-        return (`curl -o /dev/null --silent -Iw '%{http_code}' -L "#{tarball_url}"` == "200")
+        return ReactNativePodsUtils.artifact_exists?(tarball_url)
     end
 
     def self.rncore_log(message, level = :info)

packages/react-native/scripts/cocoapods/rndependencies.rb

@@ -248,7 +248,7 @@ def self.nightly_tarball_url(version, build_type)
         artifact_name = "reactnative-dependencies-#{build_type.to_s}.tar.gz"
         xml_url = "https://central.sonatype.com/repository/maven-snapshots/com/facebook/react/#{artifact_coordinate}/#{version}-SNAPSHOT/maven-metadata.xml"
 
-        response = Net::HTTP.get_response(URI(xml_url))
+        response = ReactNativePodsUtils.memoized_get_response(xml_url)
         if response.is_a?(Net::HTTPSuccess)
           xml = REXML::Document.new(response.body)
           timestamp = xml.elements['metadata/versioning/snapshot/timestamp'].text
@@ -378,11 +378,11 @@ def self.artifacts_dir()
         return File.join(Pod::Config.instance.project_pods_root, "ReactNativeDependencies-artifacts")
     end
 
-    # This function checks that ReactNativeDependencies artifact exists on the maven repo
+    # This function checks that ReactNativeDependencies artifact exists on the maven repo.
+    # The probe is memoized, so repeated podspec evaluations in one `pod install`
+    # don't re-request the same URL.
     def self.artifact_exists(tarball_url)
-        # -L is used to follow redirects, useful for the nightlies
-        # I also needed to wrap the url in quotes to avoid escaping & and ?.
-        return (`curl -o /dev/null --silent -Iw '%{http_code}' -L "#{tarball_url}"` == "200")
+        return ReactNativePodsUtils.artifact_exists?(tarball_url)
     end
 
     def self.rndeps_log(message, level = :info)

packages/react-native/scripts/cocoapods/utils.rb

@@ -6,6 +6,7 @@
 require 'shellwords'
 require 'digest'
 require 'uri'
+require 'net/http'
 
 require_relative "./helpers.rb"
 require_relative "./jsengine.rb"
@@ -757,6 +758,47 @@ def self.resolve_use_frameworks(spec, header_mappings_dir: nil, module_name: nil
         end
     end
 
+    # ============================ #
+    # Network request memoization  #
+    # ============================ #
+    # CocoaPods evaluates the prebuilt podspecs several times during a single
+    # `pod install`, and every evaluation re-resolves the artifact URLs from
+    # scratch: existence probes against the mirror/Maven Central and nightly
+    # metadata lookups. The answers should not change within one install, so
+    # each request is issued at most once per process and then served from
+    # these in-memory caches.
+    @@artifact_exists_cache = {}
+    @@get_response_cache = {}
+
+    # Memoized existence probe (HTTP HEAD) for a prebuilt artifact URL.
+    # Only conclusive answers are cached. If curl never got an HTTP status
+    # (DNS failure, no route, ...) the probe is left uncached so that a
+    # transient hiccup doesn't permanently mark the artifact as missing.
+    def self.artifact_exists?(tarball_url)
+        unless @@artifact_exists_cache.key?(tarball_url)
+            # -L is used to follow redirects, useful for the nightlies
+            # The url is wrapped in quotes to avoid escaping & and ?.
+            http_code = `curl -o /dev/null --silent -Iw '%{http_code}' -L "#{tarball_url}"`
+            return false if !$?.success? || http_code == "000"
+            @@artifact_exists_cache[tarball_url] = (http_code == "200")
+        end
+        return @@artifact_exists_cache[tarball_url]
+    end
+
+    # Memoized HTTP GET for small metadata lookups (Maven snapshot metadata).
+    # Returns the Net::HTTPResponse. Only successful responses are cached:
+    # raised network errors propagate uncached, and non-2xx responses (a
+    # transient 5xx, a 404) are returned without being stored, so a later
+    # call within the same process can retry.
+    def self.memoized_get_response(url)
+        unless @@get_response_cache.key?(url)
+            response = Net::HTTP.get_response(URI(url))
+            return response unless response.is_a?(Net::HTTPSuccess)
+            @@get_response_cache[url] = response
+        end
+        return @@get_response_cache[url]
+    end
+
     # ==================== #
     # Shared download cache #
     # ==================== #

packages/react-native/sdks/hermes-engine/hermes-utils.rb

@@ -10,6 +10,14 @@
 MAVEN_CENTRAL_REPOSITORY = "https://repo1.maven.org/maven2"
 REACT_NATIVE_MAVEN_MIRROR_REPOSITORY = "https://repo.reactnative.dev/maven2"
 
+# Memoized results of requests to the Maven repositories (mirror or central).
+# hermes-engine.podspec is evaluated several times during a single
+# `pod install`, and every evaluation re-resolves the artifact source from
+# scratch; without memoization that re-issues identical artifact existence
+# probes. The answers should not change within one install, so each request
+# is issued at most once per process.
+HERMES_ARTIFACT_EXISTS_CACHE = {}
+
 module HermesEngineSourceType
     LOCAL_PREBUILT_TARBALL = :local_prebuilt_tarball
     DOWNLOAD_PREBUILD_RELEASE_TARBALL = :download_prebuild_release_tarball
@@ -339,14 +347,23 @@ def resolve_url_redirects(url)
 
 # This function checks that Hermes artifact exists.
 # As of now it should check it on the Maven repo.
+# The probe is memoized, so repeated podspec evaluations in one `pod install`
+# don't re-request the same URL. Only conclusive answers are cached: if curl
+# never got an HTTP status (DNS failure, no route, ...) the probe is left
+# uncached so a transient hiccup doesn't permanently mark the artifact as
+# missing.
 #
 # Parameters
-# - version: the version of React Native
-# - build_type: debug or release
+# - tarball_url: the URL of the Hermes artifact to probe
 def hermes_artifact_exists(tarball_url)
-    # -L is used to follow redirects, useful for the nightlies
-    # I also needed to wrap the url in quotes to avoid escaping & and ?.
-    return (`curl -o /dev/null --silent -Iw '%{http_code}' -L "#{tarball_url}"` == "200")
+    unless HERMES_ARTIFACT_EXISTS_CACHE.key?(tarball_url)
+        # -L is used to follow redirects, useful for the nightlies
+        # I also needed to wrap the url in quotes to avoid escaping & and ?.
+        http_code = `curl -o /dev/null --silent -Iw '%{http_code}' -L "#{tarball_url}"`
+        return false if !$?.success? || http_code == "000"
+        HERMES_ARTIFACT_EXISTS_CACHE[tarball_url] = (http_code == "200")
+    end
+    return HERMES_ARTIFACT_EXISTS_CACHE[tarball_url]
 end
 
 def hermes_log(message, level = :warning)