fix: Reject row_keys larger than 4KiB for mutations (and range set creation).

[marete]

This change is 

[prawilny]

Reviewed 5 of 5 files at r1, all commit messages.
Reviewable status: all files reviewed, 4 unresolved discussions (waiting on @dopiera)

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google/cloud/bigtable/emulator/table.cc line 796 at r1 (raw file):

  auto const& row_prefix = request.row_key_prefix();
  if (request.row_key_prefix().size() > kMaxRowLen) {

nit: There are two ifs regarding request.row_key_preifx(), which is refered to by both request.row_key_prefix and row_prefix.
Please make both conditions use the same name so that it's clear that they both validate the same thing.

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google/cloud/bigtable/emulator/table.cc line 803 at r1 (raw file):

            absl::StrFormat("%zu", request.row_key_prefix().size())));
  }

nit: extra line, which clouds the fact that both conditions validate the same value. Maybe let's remove it?

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google/cloud/bigtable/emulator/limits.h line 23 at r1 (raw file):

namespace bigtable {
namespace emulator {
constexpr std::size_t kMaxRowLen = 2 << 21;

Isn't our constant (2**21) like 2MB, which is significantly higher than 4KiB we claim elsewhere?

Doesn't it suggest that we should store the string for human readable limit next to the value so that it can be easier to verify that they match?

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google/cloud/bigtable/google_cloud_cpp_bigtable.bzl line 207 at r1 (raw file):

    "internal/rate_limiter.cc",
    "internal/readrowsparser.cc",
    "internal/retry_context.cc",

Was it intended?

[marete]

Reviewable status: 2 of 5 files reviewed, 1 unresolved discussion (waiting on @dopiera and @prawilny)

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google/cloud/bigtable/emulator/limits.h line 23 at r1 (raw file):

Previously, prawilny (Adam Czajkowski) wrote…

Isn't our constant (2**21) like 2MB, which is significantly higher than 4KiB we claim elsewhere?

Doesn't it suggest that we should store the string for human readable limit next to the value so that it can be easier to verify that they match?

Thank you very much for this excellent catch. Meant 2 << 11