From c29b8f4284660af5016811a256bd0e0123a62861 Mon Sep 17 00:00:00 2001
From: Aaron Boodman <aaron@aaronboodman.com>
Date: Fri, 2 Oct 2020 09:26:10 -1000
Subject: [PATCH] Revert "Remove diff-server from the JS SDK (#120)"

This reverts commit 409d4ee69228078c463a9ed5edac1dee69211c28.
---
 .github/workflows/perf.js.yml         |  1 +
 HACKING.md                            |  2 +-
 bin/diff-server                       |  3 +++
 package.json                          |  6 +++++-
 tool/get-deps.sh                      |  8 +++++++-
 tool/validate-binaries-for-publish.js | 27 +++++++++++++++++++++++++++
 6 files changed, 44 insertions(+), 3 deletions(-)
 create mode 100755 bin/diff-server
 create mode 100755 tool/validate-binaries-for-publish.js

diff --git a/.github/workflows/perf.js.yml b/.github/workflows/perf.js.yml
index ab573b30..05211e93 100644
--- a/.github/workflows/perf.js.yml
+++ b/.github/workflows/perf.js.yml
@@ -17,6 +17,7 @@ jobs:
 
       - run: npm ci
       - run: npm run build --if-present
+      - run: git restore --quiet bin/diff-server
 
       # Run benchmark and stores the output to a file
       - name: Run benchmark
diff --git a/HACKING.md b/HACKING.md
index e0272106..b51a6651 100644
--- a/HACKING.md
+++ b/HACKING.md
@@ -1,6 +1,6 @@
 # Getting binary dependencies
 
-`npm install` automatically downloads the correct version of the wasm bundle.
+`npm install` automatically downloads the correct version of the wasm bundle and `diff-server`.
 
 # Building against a dev version of repc
 
diff --git a/bin/diff-server b/bin/diff-server
new file mode 100755
index 00000000..8faeb95a
--- /dev/null
+++ b/bin/diff-server
@@ -0,0 +1,3 @@
+#!/usr/bin/env node
+console.error('diff-server: Failed to install correctly');
+process.exit(1);
diff --git a/package.json b/package.json
index cbdcaf9f..82330cf5 100644
--- a/package.json
+++ b/package.json
@@ -13,10 +13,14 @@
     "build": "tsc && rm -rf out/wasm && mkdir out/wasm && cp -R src/wasm/* out/wasm",
     "build:watch": "tsc --watch",
     "build:cjs": "tsc --outDir out.cjs --module CommonJS && rm -rf out.cjs/wasm && mkdir out.cjs/wasm && cp -R src/wasm/* out.cjs/wasm",
+    "start:diff-server": "bin/diff-server --db=/tmp/diffs serve",
     "postinstall": "rm -f node_modules/fetch-mock/esm/client.d.ts && tool/get-deps.sh",
-    "prepublishOnly": "npm run lint && npm run test && rm -rf out && npm run build && rm -rf out.cjs && npm run build:cjs",
+    "prepublishOnly": "tool/validate-binaries-for-publish.js && npm run lint && npm run test && rm -rf out && npm run build && rm -rf out.cjs && npm run build:cjs",
     "perf": "node perf/runner.mjs"
   },
+  "bin": {
+    "diff-server": "bin/diff-server"
+  },
   "devDependencies": {
     "@esm-bundle/chai": "^4.1.5",
     "@types/mocha": "^8.0.3",
diff --git a/tool/get-deps.sh b/tool/get-deps.sh
index 4de183b1..79f66176 100755
--- a/tool/get-deps.sh
+++ b/tool/get-deps.sh
@@ -17,8 +17,14 @@ REPC_VERSION='v0.9.0'
     exit
   fi
 
+  # Diff server is a public interface. We *do* maintain backward compat.
+  # We download the latest release.
+  echo "Fetching diff-server..."
+  URL="https://github.com/rocicorp/diff-server/releases/latest/download/diffs-$PLATFORM"
+  curl -L -f $URL > bin/diff-server
+  chmod u+x bin/diff-server
+
   echo "Fetching repc..."
-  mkdir -p bin
   URL="https://github.com/rocicorp/repc/releases/download/$REPC_VERSION/repc.zip"
   curl -L -f $URL > bin/repc.zip
   cd bin
diff --git a/tool/validate-binaries-for-publish.js b/tool/validate-binaries-for-publish.js
new file mode 100755
index 00000000..74c9abd7
--- /dev/null
+++ b/tool/validate-binaries-for-publish.js
@@ -0,0 +1,27 @@
+#!/usr/bin/env node
+'use strict';
+
+// This file is used to ensure that we are not trying to publish the downloaded
+// binaries.
+
+const {existsSync, statSync} = require('fs');
+const {join} = require('path');
+
+function validateFile(name) {
+  const p = join(__dirname, '..', 'bin', name);
+  if (!existsSync(p)) {
+    console.error(`${name} does not exist`);
+    process.exit(1);
+  }
+
+  // If it exists, make sure that this is not the compiled binary.
+  const stat = statSync(p);
+  if (stat.size > 10000) {
+    console.error(
+      `${name} looks too large. Has it been replaced by the binary?`,
+    );
+    process.exit(1);
+  }
+}
+
+validateFile('diff-server');