Thanks for the response. I tried MetadataMap<>::Log(), but it didn't
iterate over the peer string either (and I verified that the peer string is
present by calling batch.get_pointer(grpc_core::PeerString()). I then
thought perhaps MetadataMap<>::ForEach would do the trick, since its
comment says "Like Encode, but also visit the non-encodable fields". But,
then I noticed that Log uses ForEach, so the comment for ForEach must be
stale.
Any other suggestions?
-John-
On Thursday, October 12, 2023 at 4:22:34 PM UTC-7 Craig Tiller wrote:
> (take a look at MetdataMap<>::Log() for an API to get a textual
> representation out of *all* the things)
>
> On Thu, Oct 12, 2023 at 4:21 PM Craig Tiller <cti...@google.com> wrote:
>
>> `PeerString` (and some others) are Non-encodable metadata: they're
>> getting carried around there because they make sense at the same times as
>> metadata, but they don't go out on the wire.
>> So... being non-encodable Encode() skips them.
>>
>> There's some logging helpers that will catch them, so they show up as
>> debug text, but they're not directly iterable right now.
>>
>> On Thu, Oct 12, 2023 at 3:53 PM John Ousterhout <john.ou...@gmail.com>
>> wrote:
>>
>>> In the Homa module for gRPC there are a few places where the code needs
>>> to iterate over all of the values in a grpc_metadata_batch, but there are
>>> currently cases where my code isn't seeing all of the values. Here is an
>>> example from my code that attempts to log all of the values in a batch. The
>>> code invokes the Encode method, passing it a MetataLogger object:
>>>
>>> grpc_metadata_batch *batch;
>>> MetadataLogger logger(separator);
>>> batch->Encode(&logger);
>>>
>>> Here is the definition of the logger object:
>>>
>>> class MetadataLogger {
>>> public:
>>> MetadataLogger(const char *separator) : separator(separator) {}
>>>
>>> void Encode(const grpc_core::Slice &key, const grpc_core::Slice
>>> &value)
>>> {
>>> uint32_t keyLength = key.length();
>>> uint32_t valueLength = value.length();
>>> Mock::logPrintf(separator, "metadata %.*s: %.*s", keyLength,
>>> key.data(), valueLength, value.data());
>>> }
>>>
>>> template <typename MetadataTrait>
>>> void Encode(MetadataTrait, const grpc_core::Slice &value)
>>> {
>>> absl::string_view key = MetadataTrait::key();
>>> uint32_t keyLength = key.length();
>>> uint32_t valueLength = value.length();
>>> Mock::logPrintf(separator, "metadata %.*s: %.*s", keyLength,
>>> key.data(), valueLength, value.data());
>>> }
>>>
>>> template <typename MetadataTrait>
>>> void Encode(MetadataTrait, const typename MetadataTrait::ValueType&
>>> value)
>>> {
>>> absl::string_view key = MetadataTrait::key();
>>> uint32_t keyLength = key.length();
>>> const grpc_core::Slice& slice =
>>> grpc_core::MetadataValueAsSlice<MetadataTrait>(value);
>>> uint32_t valueLength = slice.length();
>>> Mock::logPrintf(separator, "metadata %.*s: %.*s", keyLength,
>>> key.data(), valueLength, slice.data());
>>> }
>>>
>>> const char *separator;
>>> };
>>>
>>> The class has 3 different Encode methods, intended to catch all of the
>>> different variants of metadata. However, it doesn't seem to be catching
>>> absolutely all of them. In particular, if I set the PeerString value, where
>>> the key is grpc_core::PeerString(), none of these methods gets invoked. Are
>>> there other variants of Encode that I need to define to catch this key?
>>> What do I need to do to be sure I'm catching absolutely all of the metadata
>>> entries? Is there a better way I should be doing this?
>>>
>>> Thanks in advance for any help you can provide.
>>>
>>> -John-
>>>
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "grpc.io" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to grpc-io+u...@googlegroups.com.
>>> To view this discussion on the web visit
>>> https://groups.google.com/d/msgid/grpc-io/f14fe33f-5f76-4f6a-9066-b9c920ed9835n%40googlegroups.com
>>>
>>> <https://groups.google.com/d/msgid/grpc-io/f14fe33f-5f76-4f6a-9066-b9c920ed9835n%40googlegroups.com?utm_medium=email&utm_source=footer>
>>> .
>>>
>>
--
You received this message because you are subscribed to the Google Groups
"grpc.io" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to grpc-io+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/grpc-io/68277d44-9d1f-48df-b973-fff314e4feaen%40googlegroups.com.
