3 files changed, 53 insertions, 35 deletions

diff --git a/editors/code/src/installation/download_artifact.ts b/editors/code/src/installation/download_artifact.ts
index 356723aba..8ed99bf0a 100644
--- a/editors/code/src/installation/download_artifact.ts
+++ b/editors/code/src/installation/download_artifact.ts
@@ -5,7 +5,6 @@ import { strict as assert } from "assert";
 
 import { ArtifactReleaseInfo } from "./interfaces";
 import { downloadFile } from "./download_file";
-import { throttle } from "throttle-debounce";
 
 /**
  * Downloads artifact from given `downloadUrl`.
@@ -38,19 +37,15 @@ export async function downloadArtifact(
         async (progress, _cancellationToken) => {
             let lastPrecentage = 0;
             const filePermissions = 0o755; // (rwx, r_x, r_x)
-            await downloadFile(downloadUrl, installationPath, filePermissions, throttle(
-                200,
-                /* noTrailing: */ true,
-                (readBytes, totalBytes) => {
-                    const newPercentage = (readBytes / totalBytes) * 100;
-                    progress.report({
-                        message: newPercentage.toFixed(0) + "%",
-                        increment: newPercentage - lastPrecentage
-                    });
+            await downloadFile(downloadUrl, installationPath, filePermissions, (readBytes, totalBytes) => {
+                const newPercentage = (readBytes / totalBytes) * 100;
+                progress.report({
+                    message: newPercentage.toFixed(0) + "%",
+                    increment: newPercentage - lastPrecentage
+                });
 
-                    lastPrecentage = newPercentage;
-                })
-            );
+                lastPrecentage = newPercentage;
+            });
         }
     );
 }
diff --git a/editors/code/src/installation/fetch_artifact_release_info.ts b/editors/code/src/installation/fetch_artifact_release_info.ts
index 1b6fc8d48..b1b5a3485 100644
--- a/editors/code/src/installation/fetch_artifact_release_info.ts
+++ b/editors/code/src/installation/fetch_artifact_release_info.ts
@@ -4,41 +4,61 @@ import { log } from "../util";
 
 const GITHUB_API_ENDPOINT_URL = "https://api.github.com";
 
-
 /**
- * Fetches the release with `releaseTag` (or just latest release when not specified)
- * from GitHub `repo` and returns metadata about `artifactFileName` shipped with
- * this release or `null` if no such artifact was published.
+ * Fetches the release with `releaseTag` from GitHub `repo` and
+ * returns metadata about `artifactFileName` shipped with
+ * this release.
+ *
+ * @throws Error upon network failure or if no such repository, release, or artifact exists.
  */
 export async function fetchArtifactReleaseInfo(
-    repo: GithubRepo, artifactFileName: string, releaseTag?: string
-): Promise<null | ArtifactReleaseInfo> {
+    repo: GithubRepo,
+    artifactFileName: string,
+    releaseTag: string
+): Promise<ArtifactReleaseInfo> {
 
     const repoOwner = encodeURIComponent(repo.owner);
     const repoName = encodeURIComponent(repo.name);
 
-    const apiEndpointPath = releaseTag
-        ? `/repos/${repoOwner}/${repoName}/releases/tags/${releaseTag}`
-        : `/repos/${repoOwner}/${repoName}/releases/latest`;
+    const apiEndpointPath = `/repos/${repoOwner}/${repoName}/releases/tags/${releaseTag}`;
 
     const requestUrl = GITHUB_API_ENDPOINT_URL + apiEndpointPath;
 
-    // We skip runtime type checks for simplicity (here we cast from `any` to `GithubRelease`)
-
     log.debug("Issuing request for released artifacts metadata to", requestUrl);
 
-    // FIXME: handle non-ok response
-    const response: GithubRelease = await fetch(requestUrl, {
-        headers: { Accept: "application/vnd.github.v3+json" }
-    })
-        .then(res => res.json());
+    const response = await fetch(requestUrl, { headers: { Accept: "application/vnd.github.v3+json" } });
 
-    const artifact = response.assets.find(artifact => artifact.name === artifactFileName);
+    if (!response.ok) {
+        log.error("Error fetching artifact release info", {
+            requestUrl,
+            releaseTag,
+            artifactFileName,
+            response: {
+                headers: response.headers,
+                status: response.status,
+                body: await response.text(),
+            }
+        });
+
+        throw new Error(
+            `Got response ${response.status} when trying to fetch ` +
+            `"${artifactFileName}" artifact release info for ${releaseTag} release`
+        );
+    }
 
-    if (!artifact) return null;
+    // We skip runtime type checks for simplicity (here we cast from `any` to `GithubRelease`)
+    const release: GithubRelease = await response.json();
+
+    const artifact = release.assets.find(artifact => artifact.name === artifactFileName);
+
+    if (!artifact) {
+        throw new Error(
+            `Artifact ${artifactFileName} was not found in ${release.name} release!`
+        );
+    }
 
     return {
-        releaseName: response.name,
+        releaseName: release.name,
         downloadUrl: artifact.browser_download_url
     };
 
diff --git a/editors/code/src/installation/server.ts b/editors/code/src/installation/server.ts
index 685abfdc6..cb5e56844 100644
--- a/editors/code/src/installation/server.ts
+++ b/editors/code/src/installation/server.ts
@@ -63,7 +63,7 @@ export async function ensureServerBinary(source: null | BinarySource): Promise<n
 
 async function downloadServer(source: BinarySource.GithubRelease): Promise<boolean> {
     try {
-        const releaseInfo = (await fetchArtifactReleaseInfo(source.repo, source.file, source.version))!;
+        const releaseInfo = await fetchArtifactReleaseInfo(source.repo, source.file, source.version);
 
         await downloadArtifact(releaseInfo, source.file, source.dir, "language server");
         await setServerVersion(source.storage, releaseInfo.releaseName);
@@ -88,9 +88,12 @@ async function downloadServer(source: BinarySource.GithubRelease): Promise<boole
         return false;
     }
 
-    if (!isBinaryAvailable(path.join(source.dir, source.file))) assert(false,
+    const binaryPath = path.join(source.dir, source.file);
+
+    assert(isBinaryAvailable(binaryPath),
         `Downloaded language server binary is not functional.` +
-        `Downloaded from: ${JSON.stringify(source, null, 4)}`
+        `Downloaded from GitHub repo ${source.repo.owner}/${source.repo.name} ` +
+        `to ${binaryPath}`
     );
 
     vscode.window.showInformationMessage(