Ignore invalid range in blob download

[cnaj]

Fix #2458, based on #2461

I'm not sure how to provoke an invalid range header in the unit tests; @blueww can you give me a hint?

[cnaj]

@microsoft-github-policy-service agree company="corpuls"

[blueww]

@EmmaZhu

Do you have any idea how to input a invalid range header like "0--1" in download blob API by JS SDK (in Azurite test)?

[EmmaZhu]

Following is sample to set a customized header to a blobClient instance:

// Define a PipelinePolicy to set a customized header
export const injectorPolicyName = "injectorPolicy";

export function injectorPolicy(): PipelinePolicy {
  return {
    name: injectorPolicyName,
    async sendRequest(request: PipelineRequest, next: SendRequest): Promise<PipelineResponse> {
      request.headers.set('headername', `headervalue`);
      return next(request);
    },
  };
}

    // Insert the policy to pipeline in blobClient's contenxt
    const injector = injectorPolicy();

    const pipeline: Pipeline = (blobClient as any).storageClientContext.pipeline;
    pipeline.addPolicy(injector, {phase: 'Retry'});

   // code against blobClient

[blueww]

@cnaj
Would you please look at the sample code from Emma for how to add customized header when send request with JS storage SDK, and follow up it to add the test case?

[cnaj]

I'm still trying to figure out how to apply @EmmaZhu's suggestion. For instance, there is no pipeline property on blobClient.storageClientContext, as far as I can see in the debugger. Also, this is an undocumented feature for which I don't have enough information... Could you please clarify?

[blueww]

@EmmaZhu
Would you please look at the above comments, and share the info that @cnaj needed?
Thanks!