From 0f4c885acf88b9a6c57d04cb6bfd05852f0acf67 Mon Sep 17 00:00:00 2001
From: Derek Dohler <ddohler@azavea.com>
Date: Fri, 30 Sep 2022 17:06:33 -0400
Subject: [PATCH 1/2] Validate defaultPrefix is a valid URL

If it isn't, use undefined instead. An invalid (but non-undefined) URL
will always cause loam.initialize() to throw an exception, even if the
user attempts to provide a valid URL as a parameter to initialize().
This now validates defaultPrefix before attempting to use it, and
uses undefined if the defaultPrefix is not a valid URL. The user in this
case will be _required_ to provide a valid absolute URL parameter to
initialize(), because there is no default to fall back on.
---
 CHANGELOG                  |  3 +++
 README.md                  |  2 +-
 src/workerCommunication.js | 13 ++++++++++++-
 test/loam.spec.js          | 13 ++-----------
 4 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index b431625..d91493d 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,6 @@
+## UPCOMING
+- Allow users to specify a valid absolute URL when the default URL is invalid
+
 ## 1.1.1 (2022-09-30)
 - Document bytes() method
 - Fix production bundle not including unminified assets.
diff --git a/README.md b/README.md
index 4d8f9e3..fbc568f 100644
--- a/README.md
+++ b/README.md
@@ -58,7 +58,7 @@ Although this function is called automatically by other functions, such as `loam
 
 This function is safe to call multiple times.
 #### Parameters
-- `pathPrefix` (optional): The path or URL that Loam should use as a prefix when fetching its Web Worker. If left undefined, Loam will make a best guess based on the source path of its own `<script>` element. URLs with domains may be used to enable Loam to be loaded from CDNs like unpkg, but the file name should be left off.
+- `pathPrefix` (optional): The path or URL that Loam should use as a prefix when fetching its Web Worker. If left undefined, Loam will make a best guess based on the source path of its own `<script>` element. If Loam has no `<script>` element (e.g. because you are using dynamic imports), then autodetecting a prefix will fail and this parameter must be provided. URLs with domains may be used to enable Loam to be loaded from CDNs like unpkg, but the file name should be left off.
 - `gdalPrefix` (optional): The path or URL that Loam should use as a prefix when fetching WebAssembly assets for GDAL. If left undefined, Loam will use the same value as `pathPrefix`. URLs with domains may be used to enable loading from CDNs like unpkg, but the file name should be left off. If Loam fails to work properly and you see requests resulting in 404s or other errors for the `gdal.*` assets listed above, you will need to set `pathPrefix`, or this parameter, or both, to the correct locations where Loam can find those assets.
 #### Return value
 A promise that resolves when Loam is initialized. All of the functions described in this document wait for this promise's resolution when executing, so paying attention to whether this promise has resolved or not is not required. However, it may be helpful to do so in some circumstances, for example, if you want to display a visual indicator that your app is ready.
diff --git a/src/workerCommunication.js b/src/workerCommunication.js
index f75e326..2f76656 100644
--- a/src/workerCommunication.js
+++ b/src/workerCommunication.js
@@ -56,7 +56,18 @@ const THIS_SCRIPT = _scripts[_scripts.length - 1];
 
 // Inspired by Emscripten's method for doing the same thing
 function getPathPrefix() {
-    return THIS_SCRIPT.src.substring(0, THIS_SCRIPT.src.lastIndexOf('/')) + '/';
+    const prefix = THIS_SCRIPT.src.substring(0, THIS_SCRIPT.src.lastIndexOf('/')) + '/';
+
+    try {
+        // prefix must be a valid URL so validate that it is before returning
+        // eslint-disable-next-line no-new
+        new URL(prefix);
+        return prefix;
+    } catch (error) {
+        // Returning undefined will require the user to specify a valid absolute URL for loamPrefix
+        // at least
+        return undefined;
+    }
 }
 
 // Destroy the worker and clear the promise so that calling initWorker will make a new one.
diff --git a/test/loam.spec.js b/test/loam.spec.js
index c31b586..917e747 100644
--- a/test/loam.spec.js
+++ b/test/loam.spec.js
@@ -188,12 +188,7 @@ describe('Given that loam exists', () => {
                 .then((ds) => ds.transform())
                 .then((transform) => {
                     expect(transform).to.deep.equal([
-                        -8380165.213197844,
-                        2416.6666666666665,
-                        0,
-                        4886134.645645497,
-                        0,
-                        -2468.75,
+                        -8380165.213197844, 2416.6666666666665, 0, 4886134.645645497, 0, -2468.75,
                     ]);
                 });
         });
@@ -240,11 +235,7 @@ describe('Given that loam exists', () => {
                     // Determined out-of-band by executing gdalwarp on the command line.
                     .then((transform) => {
                         expect(transform).to.deep.equal([
-                            -75.2803049446235,
-                            0.019340471787624117,
-                            0.0,
-                            40.13881222863268,
-                            0.0,
+                            -75.2803049446235, 0.019340471787624117, 0.0, 40.13881222863268, 0.0,
                             -0.019340471787624117,
                         ]);
                     })

From 9507292cddf3bebadf2a073d92f037d48c63121b Mon Sep 17 00:00:00 2001
From: Derek Dohler <ddohler@azavea.com>
Date: Wed, 12 Oct 2022 09:11:09 -0400
Subject: [PATCH 2/2] Bump version to 1.1.2

---
 CHANGELOG    | 2 ++
 package.json | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG b/CHANGELOG
index d91493d..b887e32 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,4 +1,6 @@
 ## UPCOMING
+
+## 1.1.2 (2022-10-12)
 - Allow users to specify a valid absolute URL when the default URL is invalid
 
 ## 1.1.1 (2022-09-30)
diff --git a/package.json b/package.json
index 1097483..c106e71 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "loam",
-    "version": "1.1.1",
+    "version": "1.1.2",
     "description": "Javascript wrapper for GDAL in the browser",
     "main": "lib/loam.js",
     "scripts": {