From 03a8522b3e192cc8827f2476f9d476942b7ed365 Mon Sep 17 00:00:00 2001
From: James Fenn <me@jfenn.me>
Date: Fri, 31 Jul 2020 17:03:06 -0400
Subject: [PATCH] add basic js disk cache with node-persist

---
 .gitignore                                    |  1 +
 example-js/index.html                         |  2 +-
 example-nodejs/src/index.js                   | 12 ++--
 gitrest/build.gradle                          |  2 +
 .../me/jfenn/gitrest/service/DiskCache.kt     |  4 +-
 .../me/jfenn/gitrest/service/MemoryCache.kt   |  4 +-
 .../kotlin/me/jfenn/gitrest/service/Cache.kt  |  4 +-
 .../me/jfenn/gitrest/service/NoCache.kt       |  4 +-
 .../kotlin/{RequestProvider.kt => Client.kt}  | 25 +++----
 gitrest/src/jsMain/kotlin/gitrest/js/Repo.kt  |  1 +
 .../me/jfenn/gitrest/service/DiskCache.kt     | 65 +++++++++++++++++++
 .../me/jfenn/gitrest/service/MemoryCache.kt   |  4 +-
 .../me/jfenn/gitrest/service/MemoryCache.kt   |  4 +-
 13 files changed, 104 insertions(+), 28 deletions(-)
 rename gitrest/src/jsMain/kotlin/{RequestProvider.kt => Client.kt} (71%)
 create mode 100644 gitrest/src/jsMain/kotlin/me/jfenn/gitrest/service/DiskCache.kt

diff --git a/.gitignore b/.gitignore
index 3956314..88d967f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,6 +12,7 @@
 .classpath
 .settings/
 .yarnrc
+.node-persist/
 yarn.lock
 node_modules
 /npm/index.js
diff --git a/example-js/index.html b/example-js/index.html
index 4e3edc0..d08d3bf 100644
--- a/example-js/index.html
+++ b/example-js/index.html
@@ -16,7 +16,7 @@
 </body>
 <script src="./gitrest.js"></script>
 <script type="text/javascript">
-    let delegate = new gitrest.RequestProvider();
+    let delegate = new gitrest.Client();
     delegate.getRepo("github@api.github.com:fennifith/Attribouter").then((repo) => {
         console.log(repo);
         document.getElementById("repoName").innerText = repo.id;
diff --git a/example-nodejs/src/index.js b/example-nodejs/src/index.js
index fcd44b1..6055189 100644
--- a/example-nodejs/src/index.js
+++ b/example-nodejs/src/index.js
@@ -1,11 +1,15 @@
-const { RequestProvider } = require("git-rest-wrapper-gitrest");
+const { Client } = require("git-rest-wrapper-gitrest");
 
-let delegate = new RequestProvider();
+let gitrest = new Client({
+    cache: {
+        type: "disk"
+    }
+});
 
-delegate.getUser("fennifith").then((obj) => {
+gitrest.getUser("fennifith").then((obj) => {
     console.log(obj);
 });
 
-delegate.getRepo("gitlab@salsa.debian.org:reproducible-builds/reproducible-website").then((obj) => {
+gitrest.getRepo("gitlab@salsa.debian.org:reproducible-builds/reproducible-website").then((obj) => {
     console.log(obj);
 });
diff --git a/gitrest/build.gradle b/gitrest/build.gradle
index 7f9d675..83c1e02 100644
--- a/gitrest/build.gradle
+++ b/gitrest/build.gradle
@@ -147,6 +147,8 @@ kotlin {
                 implementation npm("node-fetch", "2.6.0")
                 implementation npm("text-encoding", "0.7.0")
                 implementation npm("abort-controller", "3.0.0")
+
+                implementation npm("node-persist", "3.1.0")
             }
         }
         jsTest {
diff --git a/gitrest/src/androidMain/kotlin/me/jfenn/gitrest/service/DiskCache.kt b/gitrest/src/androidMain/kotlin/me/jfenn/gitrest/service/DiskCache.kt
index c199377..c65953f 100644
--- a/gitrest/src/androidMain/kotlin/me/jfenn/gitrest/service/DiskCache.kt
+++ b/gitrest/src/androidMain/kotlin/me/jfenn/gitrest/service/DiskCache.kt
@@ -25,7 +25,7 @@ class DiskCache(
     fun String.cacheFile() = File(cacheDir, "${this.replace(File.separator, "_")}.json")
 
     @ImplicitReflectionSerializer
-    override fun set(key: String, value: Any) {
+    override suspend fun set(key: String, value: Any) {
         // obtain a serializer + type for the value (this is all just a ridiculous hack)
         val serializer: KSerializer<Any>
         val typeName: String
@@ -51,7 +51,7 @@ class DiskCache(
     }
 
     @ImplicitReflectionSerializer
-    override fun <T> get(key: String): T? {
+    override suspend fun <T> get(key: String): T? {
         return try {
             // check contents; destructure file parts if safe
             val fileContents = key.cacheFile().readText().split("#", limit = 3)
diff --git a/gitrest/src/androidMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt b/gitrest/src/androidMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
index dcf02a6..0afdcc9 100644
--- a/gitrest/src/androidMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
+++ b/gitrest/src/androidMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
@@ -20,7 +20,7 @@ actual class MemoryCache actual constructor(
     private val referenceQueue = ReferenceQueue<Any>()
     private val map = HashMap<String, WeakEntry>()
 
-    override fun set(key: String, value: Any) {
+    override suspend fun set(key: String, value: Any) {
         // remove any invalid references
         var weakEntry = referenceQueue.poll() as WeakEntry?
         while (weakEntry != null) {
@@ -32,7 +32,7 @@ actual class MemoryCache actual constructor(
         underlyingCache.set(key, value)
     }
 
-    override fun <T> get(key: String): T? {
+    override suspend fun <T> get(key: String): T? {
         val weakEntry = map[key]
         weakEntry?.get()?.let {
             return it as? T
diff --git a/gitrest/src/commonMain/kotlin/me/jfenn/gitrest/service/Cache.kt b/gitrest/src/commonMain/kotlin/me/jfenn/gitrest/service/Cache.kt
index 5ddecdd..896f5cf 100644
--- a/gitrest/src/commonMain/kotlin/me/jfenn/gitrest/service/Cache.kt
+++ b/gitrest/src/commonMain/kotlin/me/jfenn/gitrest/service/Cache.kt
@@ -2,8 +2,8 @@ package me.jfenn.gitrest.service
 
 interface Cache {
 
-    fun set(key: String, value: Any)
+    suspend fun set(key: String, value: Any)
 
-    fun <T> get(id: String) : T?
+    suspend fun <T> get(id: String) : T?
 
 }
\ No newline at end of file
diff --git a/gitrest/src/commonMain/kotlin/me/jfenn/gitrest/service/NoCache.kt b/gitrest/src/commonMain/kotlin/me/jfenn/gitrest/service/NoCache.kt
index e512d61..354d3b6 100644
--- a/gitrest/src/commonMain/kotlin/me/jfenn/gitrest/service/NoCache.kt
+++ b/gitrest/src/commonMain/kotlin/me/jfenn/gitrest/service/NoCache.kt
@@ -3,6 +3,6 @@ package me.jfenn.gitrest.service
 import me.jfenn.gitrest.model.DelegateResource
 
 object NoCache : Cache {
-    override fun set(key: String, value: Any) {}
-    override fun <T> get(id: String): T? = null
+    override suspend fun set(key: String, value: Any) {}
+    override suspend fun <T> get(id: String): T? = null
 }
\ No newline at end of file
diff --git a/gitrest/src/jsMain/kotlin/RequestProvider.kt b/gitrest/src/jsMain/kotlin/Client.kt
similarity index 71%
rename from gitrest/src/jsMain/kotlin/RequestProvider.kt
rename to gitrest/src/jsMain/kotlin/Client.kt
index 99dcc24..03ddf29 100644
--- a/gitrest/src/jsMain/kotlin/RequestProvider.kt
+++ b/gitrest/src/jsMain/kotlin/Client.kt
@@ -1,28 +1,31 @@
-import me.jfenn.gitrest.base.ServiceBuilder
-import me.jfenn.gitrest.provider.gitea.GiteaProvider
-import me.jfenn.gitrest.provider.github.GithubProvider
-import me.jfenn.gitrest.provider.gitlab.GitlabProvider
 import gitrest.js.License
 import gitrest.js.Repo
 import gitrest.js.User
 import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.promise
 import me.jfenn.gitrest.gitrest
+import me.jfenn.gitrest.service.DiskCache
 import kotlin.js.Promise
 
 /**
  * NodeJS-usable wrapper class to convert functions/arguments into their JS-compatible versions
  */
-class RequestProvider(
-    providers: Array<ServiceBuilder<*>> = arrayOf(
-        GithubProvider,
-        GiteaProvider,
-        GitlabProvider
-    )
+class Client(
+    config: dynamic
 ) {
 
     val client = gitrest {
-        this.providers = providers
+        this.providers.forEach {
+            if (config.tokens != null) {
+                this.providers.forEach {
+                    it.tokens.putAll(config.tokens)
+                }
+            }
+
+            if (config.cache?.type == "disk") {
+                this.cache = DiskCache(this)
+            }
+        }
     }
 
     @JsName("getUser")
diff --git a/gitrest/src/jsMain/kotlin/gitrest/js/Repo.kt b/gitrest/src/jsMain/kotlin/gitrest/js/Repo.kt
index 4dc54e4..47d4b4b 100644
--- a/gitrest/src/jsMain/kotlin/gitrest/js/Repo.kt
+++ b/gitrest/src/jsMain/kotlin/gitrest/js/Repo.kt
@@ -14,5 +14,6 @@ class Repo(
     val license: License? = repo.license?.let { License(it) }
     val defaultBranch: String? = repo.defaultBranch
 
+    @JsName("getRawFileUrl")
     fun getRawFileUrl(branchName: String, filePath: String) : String? = repo.getRawFileUrl(branchName, filePath)
 }
\ No newline at end of file
diff --git a/gitrest/src/jsMain/kotlin/me/jfenn/gitrest/service/DiskCache.kt b/gitrest/src/jsMain/kotlin/me/jfenn/gitrest/service/DiskCache.kt
new file mode 100644
index 0000000..b3b3312
--- /dev/null
+++ b/gitrest/src/jsMain/kotlin/me/jfenn/gitrest/service/DiskCache.kt
@@ -0,0 +1,65 @@
+package me.jfenn.gitrest.service
+
+import kotlinx.coroutines.await
+import me.jfenn.gitrest.model.GitrestConfig
+import me.jfenn.gitrest.model.Repo
+import kotlin.js.Date
+import kotlin.js.Promise
+
+external fun require(module: String): dynamic
+
+/**
+ * Unsafe "disk cache" based on node-persist and JSON.parse.
+ */
+class DiskCache(
+    val config: GitrestConfig,
+    val cacheDuration: Long = 864000000 // cache for ~10 days by default
+) : Cache {
+
+    private var persist: dynamic = null
+    private var promisePersist: Promise<dynamic>? = null
+
+    private suspend fun getPersist() : dynamic {
+        if (persist == null) {
+            persist = require("node-persist")
+            promisePersist = (persist.init() as Promise<dynamic>)
+        }
+
+        promisePersist?.await()
+
+        return persist
+    }
+
+    /**
+     * Obtain a "version" string using properties of the Repo class
+     * - prop names are obfuscated, so this should be somewhat reliable.
+     */
+    private fun getVersion() : String {
+        val keys: (dynamic) -> Array<String> = js("Object.keys")
+        return keys(Repo())[0]
+    }
+
+    override suspend fun set(key: String, value: Any) {
+        val string = getVersion() + "#" + Date.now() + "#" + JSON.stringify(value)
+        (getPersist().setItem(key, string) as Promise<dynamic>).await()
+    }
+
+    override suspend fun <T> get(key: String): T? {
+        val string = (getPersist().getItem(key) as Promise<String?>).await() ?: return null
+
+        val stringContents = string.split("#", limit = 3)
+        if (stringContents.size != 3) return null
+        val (version, lastModified, json) = stringContents
+
+        if (version != getVersion())
+            return null
+
+        if (Date.now() - lastModified.toLong() < cacheDuration)
+            return null
+
+        return if (json.startsWith("{"))
+            JSON.parse(json)
+        else null
+    }
+
+}
diff --git a/gitrest/src/jsMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt b/gitrest/src/jsMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
index 32e2a10..bccf48d 100644
--- a/gitrest/src/jsMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
+++ b/gitrest/src/jsMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
@@ -11,12 +11,12 @@ actual class MemoryCache actual constructor(
 
     private val map = HashMap<String, Any>()
 
-    override fun set(key: String, value: Any) {
+    override suspend fun set(key: String, value: Any) {
         map[key] = value
         underlyingCache.set(key, value)
     }
 
-    override fun <T> get(key: String): T? {
+    override suspend fun <T> get(key: String): T? {
         return (map[key] ?: underlyingCache.get<T>(key)) as? T?
     }
 
diff --git a/gitrest/src/jvmMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt b/gitrest/src/jvmMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
index e04eb1b..ca22340 100644
--- a/gitrest/src/jvmMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
+++ b/gitrest/src/jvmMain/kotlin/me/jfenn/gitrest/service/MemoryCache.kt
@@ -20,7 +20,7 @@ actual class MemoryCache actual constructor(
     private val referenceQueue = ReferenceQueue<Any>()
     private val map = HashMap<String, WeakEntry>()
 
-    override fun set(key: String, value: Any) {
+    override suspend fun set(key: String, value: Any) {
         // remove any invalid references
         var weakEntry = referenceQueue.poll() as WeakEntry?
         while (weakEntry != null) {
@@ -32,7 +32,7 @@ actual class MemoryCache actual constructor(
         underlyingCache.set(key, value)
     }
 
-    override fun <T> get(key: String): T? {
+    override suspend fun <T> get(key: String): T? {
         val weakEntry = map[key]
         weakEntry?.get()?.let {
             return it as? T
-- 
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