enhance: use littlezipper instead of jszip

it's very lightweight, and uses the built-in `CompressionStream` for compression (available in CF Workers)

functions/_common/grapherRenderer.ts

@@ -17,7 +17,7 @@ import { constructReadme } from "./readmeTools"
 import { svg2png, initialize as initializeSvg2Png } from "svg2png-wasm"
 import { TimeLogger } from "./timeLogger"
 import { png, StatusError } from "itty-router"
-import JSZip from "jszip"
+import { createZip, File } from "littlezipper"
 
 import svg2png_wasm from "../../node_modules/svg2png-wasm/svg2png_wasm_bg.wasm"
 
@@ -544,14 +544,16 @@ export async function fetchZipForGrapher(
     const readme = assembleReadme(grapher)
     const csv = assembleCsv(grapher, searchParams)
     console.log("Fetched the parts, creating zip file")
-    const zip = new JSZip()
-    zip.file(
-        `${identifier.id}.metadata.json`,
-        JSON.stringify(metadata, undefined, 2)
-    )
-    zip.file(`${identifier.id}.csv`, csv)
-    zip.file("readme.md", readme)
-    const content = await zip.generateAsync({ type: "arraybuffer" })
+
+    const zipContent: File[] = [
+        {
+            path: `${identifier.id}.metadata.json`,
+            data: JSON.stringify(metadata, undefined, 2),
+        },
+        { path: `${identifier.id}.csv`, data: csv },
+        { path: "readme.md", data: readme },
+    ]
+    const content = await createZip(zipContent)
     console.log("Generated content, returning response")
     return new Response(content, {
         headers: {

functions/package.json

@@ -4,7 +4,7 @@
     "@ourworldindata/grapher": "workspace:^",
     "@ourworldindata/utils": "workspace:^",
     "itty-router": "^5.0.17",
-    "jszip": "^3.10.1",
+    "littlezipper": "^0.1.4",
     "stripe": "^14.20.0",
     "svg2png-wasm": "^1.4.1"
   },

yarn.lock

@@ -11583,13 +11583,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"immediate@npm:~3.0.5":
-  version: 3.0.6
-  resolution: "immediate@npm:3.0.6"
-  checksum: 10/f9b3486477555997657f70318cc8d3416159f208bec4cca3ff3442fd266bc23f50f0c9bd8547e1371a6b5e82b821ec9a7044a4f7b944798b25aa3cc6d5e63e62
-  languageName: node
-  linkType: hard
-
 "immutable@npm:^4.0.0, immutable@npm:^4.3.6":
   version: 4.3.6
   resolution: "immutable@npm:4.3.6"
@@ -13209,18 +13202,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"jszip@npm:^3.10.1":
-  version: 3.10.1
-  resolution: "jszip@npm:3.10.1"
-  dependencies:
-    lie: "npm:~3.3.0"
-    pako: "npm:~1.0.2"
-    readable-stream: "npm:~2.3.6"
-    setimmediate: "npm:^1.0.5"
-  checksum: 10/bfbfbb9b0a27121330ac46ab9cdb3b4812433faa9ba4a54742c87ca441e31a6194ff70ae12acefa5fe25406c432290e68003900541d948a169b23d30c34dd984
-  languageName: node
-  linkType: hard
-
 "just-diff-apply@npm:^5.2.0":
   version: 5.5.0
   resolution: "just-diff-apply@npm:5.5.0"
@@ -13486,15 +13467,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"lie@npm:~3.3.0":
-  version: 3.3.0
-  resolution: "lie@npm:3.3.0"
-  dependencies:
-    immediate: "npm:~3.0.5"
-  checksum: 10/f335ce67fe221af496185d7ce39c8321304adb701e122942c495f4f72dcee8803f9315ee572f5f8e8b08b9e8d7195da91b9fad776e8864746ba8b5e910adf76e
-  languageName: node
-  linkType: hard
-
 "lilconfig@npm:3.0.0":
   version: 3.0.0
   resolution: "lilconfig@npm:3.0.0"
@@ -13578,6 +13550,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"littlezipper@npm:^0.1.4":
+  version: 0.1.4
+  resolution: "littlezipper@npm:0.1.4"
+  checksum: 10/72b14b035a4cd2b5ac9999b955c5f17dcfa67859d83857f1c90d82a70cea4980cdc894915a8f94ed215cb5d207fcd64aa358081581349a167f7e2a261e3c5a04
+  languageName: node
+  linkType: hard
+
 "load-json-file@npm:6.2.0":
   version: 6.2.0
   resolution: "load-json-file@npm:6.2.0"
@@ -15297,7 +15276,7 @@ __metadata:
     "@ourworldindata/grapher": "workspace:^"
     "@ourworldindata/utils": "workspace:^"
     itty-router: "npm:^5.0.17"
-    jszip: "npm:^3.10.1"
+    littlezipper: "npm:^0.1.4"
     stripe: "npm:^14.20.0"
     svg2png-wasm: "npm:^1.4.1"
   languageName: unknown
@@ -15473,13 +15452,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"pako@npm:~1.0.2":
-  version: 1.0.11
-  resolution: "pako@npm:1.0.11"
-  checksum: 10/1ad07210e894472685564c4d39a08717e84c2a68a70d3c1d9e657d32394ef1670e22972a433cbfe48976cb98b154ba06855dcd3fcfba77f60f1777634bec48c0
-  languageName: node
-  linkType: hard
-
 "papaparse@npm:^5.3.1":
   version: 5.3.1
   resolution: "papaparse@npm:5.3.1"
@@ -18080,13 +18052,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"setimmediate@npm:^1.0.5":
-  version: 1.0.5
-  resolution: "setimmediate@npm:1.0.5"
-  checksum: 10/76e3f5d7f4b581b6100ff819761f04a984fa3f3990e72a6554b57188ded53efce2d3d6c0932c10f810b7c59414f85e2ab3c11521877d1dea1ce0b56dc906f485
-  languageName: node
-  linkType: hard
-
 "setprototypeof@npm:1.2.0":
   version: 1.2.0
   resolution: "setprototypeof@npm:1.2.0"