Name

lua-resty-s3 - upload content to amazon s3 with openresty

Table of Contents

• Name
• Status
• Description
• Synopsis
• Methods
  • new
  • generate_auth_headers
  • try_upload
  • upload_url
  • extract_urls
  • upload_content
• Limitations
• Installation
• TODO
• Author
• Copyright and License
• See Also

Status

This library is still under early development and considered experimental.

Description

This Lua library is a s3 uploading utility for the ngx_lua nginx module:

Synopsis

    lua_package_path "/path/to/lua-resty-s3/lib/?.lua;;";
    
    server {
        location /test {
            content_by_lua '
                local s3 = require "resty.s3"
                local s3, err = s3:new("aws-id", "aws-key")
                
                final_url, err = s3:upload_url("http://lorempixel.com/400/200/", "examplebucket", "lorempixel400x200")`
            ';
        }
        
        include conf/*.urls;
    }

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Methods

All of the commands return either something that evaluates to true on success, or nil and an error message on failure.

new

syntax: s3, err = s3:new(id, key)

Creates an uploading object. In case of failures, returns nil and a string describing the error.

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generate_auth_headers

syntax: s3, err = s3:generate_auth_headers(content_type, destination)

syntax: s3, err = s3:generate_auth_headers("binary/octet-stream", "/examplebucket/lorempixel400x200")

Creates the headers needed for authentication with amazon. In case of failures, returns nil and a string describing the error.

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try_upload

syntax: s3, err = s3:try_upload(content, destination, content_type, headers)

syntax: s3, err = s3:try_upload([[<h1>Hello</h1>]], "/examplebucket/hello", "text/html", headers)

Attempts to upload content to s3. In case of failures, returns nil and a string describing the error.

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upload_url

syntax: final_url, err = s3:upload_url(file_url, bucket, object_name, check_for_existance, add_to_existance)

syntax: final_url, err = s3:upload_url("http://lorempixel.com/400/200/", "/examplebucket/", "lorempixel400x200")

Attempts to upload content to s3 from the url set by file_url and the id/key set with new(). If object_name is supplied then that will be the name of the new file, otherwise it will hash the file_url to create a unique key for it.

Callbacks for checking something before uploading [again], and after uploading can be supplied in check_for_existance and add_to_existance. Each will be called with the object_name or a hash.

local uploaded_content = ngx.shared.uploaded_content

check = function (name)
  ok, err = uploaded_content:get(name)
  if ok then return true end
end

add = function (name)
  ok, err = uploaded_content:add(name)
  return true
end

final_url, err = s3:upload_url("http://lorempixel.com/400/200/", "/examplebucket/", "lorempixel400x200", check, add)

In case of success, returns the new url. In case of errors, returns nil with a string describing the error.

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extract_urls

syntax: s3, err = s3:extract_urls(file_content, bucket)

syntax: s3, err = s3:extract_urls([[<ahref="www.google.com"><img src="http://lorempixel.com/output/city-q-g-640-480-4.jpg" /></a>]], "/examplebucket/")

Attempts to find and upload urls from within source. In case of failures, returns nil and a string describing the error.

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upload_content

syntax: s3, err = s3:upload_content(file_content, bucket, object_name, check_for_existance, add_to_existance)

syntax: s3, err = s3:upload_content([[<ahref="www.google.com"><img src="http://lorempixel.com/output/city-q-g-640-480-4.jpg" /></a>]], "/examplebucket/", "city.jpg")

Attempts to upload content to s3 (handles all auth automatically). In case of failures, returns nil and a string describing the error.

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Limitations

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Installation

You can install it with luarocks luarocks install lua-resty-s3

Otherwise you need to configure the lua_package_path directive to add the path of your lua-nginx-loggin source to ngx_lua's LUA_PATH search path, as in

    # nginx.conf
    http {
        lua_package_path "/path/to/lua-resty-s3/lib/?.lua;;";
        ...
    }

This package also requires the luasocket and xxhash packages to be installed http://w3.impa.br/~diego/software/luasocket/ , https://github.com/mah0x211/lua-xxhash

luarocks install luasocket

Ensure that the system account running your Nginx ''worker'' proceses have enough permission to read the .lua file.

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TODO

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Author

James Marlowe "jamesmarlowe" jameskmarlowe@gmail.com, Lumate LLC.

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Copyright and License

This module is licensed under the BSD license.

Copyright (C) 2012-2014, by James Marlowe (jamesmarlowe) jameskmarlowe@gmail.com, Lumate LLC.

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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See Also

• the ngx_lua module: http://wiki.nginx.org/HttpLuaModule
• the lua-resty-hmac library

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