Use the hashicorp/go-getter to download files
* removed packer.Cache and references since packer.Cache is never used except in the download step. The download step now uses the new func packer.CachePath(targetPath) for this, the behavior is the same.
* removed download code from packer that was reimplemented into the go-getter library: progress bar, http download restart, checksuming from file, skip already downloaded files, symlinking, make a download cancellable by context.
* on windows if packer is running without symlinking rights and we are getting a local file, the file will be copied instead to avoid errors.
* added unit tests for step_download that are now CI tested on windows, mac & linux.
* files are now downloaded under cache dir `sha1(filename + "?checksum=" + checksum) + file_extension`
* since the output dir is based on the source url and the checksum, when the checksum fails, the file is auto deleted.
* a download file is protected and locked by a file lock,
* updated docs
* updated go modules and vendors
2019-03-13 07:11:58 -04:00
# gRPC-Go
[](https://travis-ci.org/grpc/grpc-go) [](https://godoc.org/google.golang.org/grpc) [](https://goreportcard.com/report/github.com/grpc/grpc-go)
The Go implementation of [gRPC ](https://grpc.io/ ): A high performance, open source, general RPC framework that puts mobile and HTTP/2 first. For more information see the [gRPC Quick Start: Go ](https://grpc.io/docs/quickstart/go.html ) guide.
Installation
------------
To install this package, you need to install Go and setup your Go workspace on your computer. The simplest way to install the library is to run:
```
$ go get -u google.golang.org/grpc
```
Prerequisites
-------------
gRPC-Go requires Go 1.9 or later.
Constraints
-----------
2019-04-20 19:53:34 -04:00
The grpc package should only depend on standard Go packages and a small number of exceptions. If your contribution introduces new dependencies which are NOT in the [list ](https://godoc.org/google.golang.org/grpc?imports ), you need a discussion with gRPC-Go authors and consultants.
Use the hashicorp/go-getter to download files
* removed packer.Cache and references since packer.Cache is never used except in the download step. The download step now uses the new func packer.CachePath(targetPath) for this, the behavior is the same.
* removed download code from packer that was reimplemented into the go-getter library: progress bar, http download restart, checksuming from file, skip already downloaded files, symlinking, make a download cancellable by context.
* on windows if packer is running without symlinking rights and we are getting a local file, the file will be copied instead to avoid errors.
* added unit tests for step_download that are now CI tested on windows, mac & linux.
* files are now downloaded under cache dir `sha1(filename + "?checksum=" + checksum) + file_extension`
* since the output dir is based on the source url and the checksum, when the checksum fails, the file is auto deleted.
* a download file is protected and locked by a file lock,
* updated docs
* updated go modules and vendors
2019-03-13 07:11:58 -04:00
Documentation
-------------
See [API documentation ](https://godoc.org/google.golang.org/grpc ) for package and API descriptions and find examples in the [examples directory ](examples/ ).
Performance
-----------
See the current benchmarks for some of the languages supported in [this dashboard ](https://performance-dot-grpc-testing.appspot.com/explore?dashboard=5652536396611584&widget=490377658&container=1286539696 ).
Status
------
General Availability [Google Cloud Platform Launch Stages ](https://cloud.google.com/terms/launch-stages ).
FAQ
---
#### Compiling error, undefined: grpc.SupportPackageIsVersion
Please update proto package, gRPC package and rebuild the proto files:
- `go get -u github.com/golang/protobuf/{proto,protoc-gen-go}`
- `go get -u google.golang.org/grpc`
- `protoc --go_out=plugins=grpc:. *.proto`
#### How to turn on logging
The default logger is controlled by the environment variables. Turn everything
on by setting:
```
GRPC_GO_LOG_VERBOSITY_LEVEL=99 GRPC_GO_LOG_SEVERITY_LEVEL=info
```
#### The RPC failed with error `"code = Unavailable desc = transport is closing"`
This error means the connection the RPC is using was closed, and there are many
possible reasons, including:
1. mis-configured transport credentials, connection failed on handshaking
1. bytes disrupted, possibly by a proxy in between
1. server shutdown
It can be tricky to debug this because the error happens on the client side but
the root cause of the connection being closed is on the server side. Turn on
logging on __both client and server__ , and see if there are any transport
errors.
