Method finalizeConfig

src/node/runtime/CoderSSHRuntime.ts:446–518

* Finalize runtime config after collision handling. * Derives Coder workspace name from branch name and computes SSH host.

(
    finalBranchName: string,
    config: RuntimeConfig
  )

   * Derives Coder workspace name from branch name and computes SSH host.
   */
  async finalizeConfig(
    finalBranchName: string,
    config: RuntimeConfig
  ): Promise<Result<RuntimeConfig, string>> {
    if (!isSSHRuntime(config) || !config.coder) {
      return Ok(config);
    }

    const coder = config.coder;
    let workspaceName = coder.workspaceName?.trim() ?? "";

    if (!coder.existingWorkspace) {
      // New workspace: derive name from mux workspace name if not provided
      if (!workspaceName) {
        workspaceName = `mux-${finalBranchName}`;
      }
      // Transform to Coder-compatible name (handles underscores, etc.)
      workspaceName = toCoderCompatibleName(workspaceName);

      // Validate against Coder's regex
      if (!CODER_NAME_REGEX.test(workspaceName)) {
        return Err(
          `Workspace name "${finalBranchName}" cannot be converted to a valid Coder name. ` +
            `Use only letters, numbers, and hyphens.`
        );
      }
    } else {
      // Existing workspace: name must be provided (selected from dropdown)
      if (!workspaceName) {
        return Err("Coder workspace name is required for existing workspaces");
      }
    }

    // Final validation
    if (!workspaceName) {
      return Err("Coder workspace name is required");
    }

    // Verify Coder auth before persisting workspace metadata.
    // Without this, existing-workspace flows skip all auth checks and can create
    // unusable entries when the user is logged out or their session has expired.
    try {
      await this.coderService.verifyAuthenticatedSession();
    } catch (error) {
      const message = getErrorMessage(error);
      return Err(
        `Failed to verify Coder authentication. ` +
          `Make sure you're logged in with the Coder CLI. ` +
          `(${message})`
      );
    }

    // Keep a provisioning session around for new workspaces so we can reuse the same token
    // when fetching template parameters during postCreateSetup.
    if (!coder.existingWorkspace) {
      try {
        await this.coderService.ensureProvisioningSession(workspaceName);
      } catch (error) {