Initial import of wrapper-validation-action

sources/src/wrapper-validation/checksums.ts

@@ -0,0 +1,55 @@
+import * as httpm from 'typed-rest-client/HttpClient'
+
+import fileWrapperChecksums from './wrapper-checksums.json'
+
+const httpc = new httpm.HttpClient('gradle/wrapper-validation-action', undefined, {allowRetries: true, maxRetries: 3})
+
+function getKnownValidChecksums(): Map<string, Set<string>> {
+    const versionsMap = new Map<string, Set<string>>()
+    for (const entry of fileWrapperChecksums) {
+        const checksum = entry.checksum
+
+        let versionNames = versionsMap.get(checksum)
+        if (versionNames === undefined) {
+            versionNames = new Set()
+            versionsMap.set(checksum, versionNames)
+        }
+
+        versionNames.add(entry.version)
+    }
+
+    return versionsMap
+}
+
+/**
+ * Known checksums from previously published Wrapper versions.
+ *
+ * Maps from the checksum to the names of the Gradle versions whose wrapper has this checksum.
+ */
+export const KNOWN_VALID_CHECKSUMS = getKnownValidChecksums()
+
+export async function fetchValidChecksums(allowSnapshots: boolean): Promise<Set<string>> {
+    const all = await httpGetJsonArray('https://services.gradle.org/versions/all')
+    const withChecksum = all.filter(
+        entry => typeof entry === 'object' && entry != null && entry.hasOwnProperty('wrapperChecksumUrl')
+    )
+    const allowed = withChecksum.filter(
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        (entry: any) => allowSnapshots || !entry.snapshot
+    )
+    const checksumUrls = allowed.map(
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        (entry: any) => entry.wrapperChecksumUrl as string
+    )
+    const checksums = await Promise.all(checksumUrls.map(async (url: string) => httpGetText(url)))
+    return new Set(checksums)
+}
+
+async function httpGetJsonArray(url: string): Promise<unknown[]> {
+    return JSON.parse(await httpGetText(url))
+}
+
+async function httpGetText(url: string): Promise<string> {
+    const response = await httpc.get(url)
+    return await response.readBody()
+}