Apache 许可证是一个宽容的自由软件许可，其由 Apache 软件基金会发布，最初是为 Apache http 服务器而撰写。Apache 许可目前有两个版本，本页面展示的是 2.0 版本。

Apache 许可证 2.0 版本的主要条件是保留版权和许可声明，如有修改，需注明修改部分内容。本许可明确了专利权授权的范围。被许可的作品可以按照不同的条款分发，无需开放源代码。

LICENSE.txt

                                 Apache License
                           Version 2.0, January 2004
                        http://www.apache.org/licenses/
 
   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
 
   1. Definitions.
 
      "License" shall mean the terms and conditions for use, reproduction,
      and distribution as defined by Sections 1 through 9 of this document.
 
      "Licensor" shall mean the copyright owner or entity authorized by
      the copyright owner that is granting the License.
 
      "Legal Entity" shall mean the union of the acting entity and all
      other entities that control, are controlled by, or are under common
      control with that entity. For the purposes of this definition,
      "control" means (i) the power, direct or indirect, to cause the
      direction or management of such entity, whether by contract or
      otherwise, or (ii) ownership of fifty percent (50%) or more of the
      outstanding shares, or (iii) beneficial ownership of such entity.
 
      "You" (or "Your") shall mean an individual or Legal Entity
      exercising permissions granted by this License.
 
      "Source" form shall mean the preferred form for making modifications,
      including but not limited to software source code, documentation
      source, and configuration files.
 
      "Object" form shall mean any form resulting from mechanical
      transformation or translation of a Source form, including but
      not limited to compiled object code, generated documentation,
      and conversions to other media types.
 
      "Work" shall mean the work of authorship, whether in Source or
      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
      (an example is provided in the Appendix below).
 
      "Derivative Works" shall mean any work, whether in Source or Object
      form, that is based on (or derived from) the Work and for which the
      editorial revisions, annotations, elaborations, or other modifications
      represent, as a whole, an original work of authorship. For the purposes
      of this License, Derivative Works shall not include works that remain
      separable from, or merely link (or bind by name) to the interfaces of,
      the Work and Derivative Works thereof.
 
      "Contribution" shall mean any work of authorship, including
      the original version of the Work and any modifications or additions
      to that Work or Derivative Works thereof, that is intentionally
      submitted to Licensor for inclusion in the Work by the copyright owner
      or by an individual or Legal Entity authorized to submit on behalf of
      the copyright owner. For the purposes of this definition, "submitted"
      means any form of electronic, verbal, or written communication sent
      to the Licensor or its representatives, including but not limited to
      communication on electronic mailing lists, source code control systems,
      and issue tracking systems that are managed by, or on behalf of, the
      Licensor for the purpose of discussing and improving the Work, but
      excluding communication that is conspicuously marked or otherwise
      designated in writing by the copyright owner as "Not a Contribution."
 
      "Contributor" shall mean Licensor and any individual or Legal Entity
      on behalf of whom a Contribution has been received by Licensor and
      subsequently incorporated within the Work.
 
   2. Grant of Copyright License. Subject to the terms and conditions of
      this License, each Contributor hereby grants to You a perpetual,
      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
      copyright license to reproduce, prepare Derivative Works of,
      publicly display, publicly perform, sublicense, and distribute the
      Work and such Derivative Works in Source or Object form.
 
   3. Grant of Patent License. Subject to the terms and conditions of
      this License, each Contributor hereby grants to You a perpetual,
      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
      (except as stated in this section) patent license to make, have made,
      use, offer to sell, sell, import, and otherwise transfer the Work,
      where such license applies only to those patent claims licensable
      by such Contributor that are necessarily infringed by their
      Contribution(s) alone or by combination of their Contribution(s)
      with the Work to which such Contribution(s) was submitted. If You
      institute patent litigation against any entity (including a
      cross-claim or counterclaim in a lawsuit) alleging that the Work
      or a Contribution incorporated within the Work constitutes direct
      or contributory patent infringement, then any patent licenses
      granted to You under this License for that Work shall terminate
      as of the date such litigation is filed.
 
   4. Redistribution. You may reproduce and distribute copies of the
      Work or Derivative Works thereof in any medium, with or without
      modifications, and in Source or Object form, provided that You
      meet the following conditions:
 
      (a) You must give any other recipients of the Work or
          Derivative Works a copy of this License; and
 
      (b) You must cause any modified files to carry prominent notices
          stating that You changed the files; and
 
      (c) You must retain, in the Source form of any Derivative Works
          that You distribute, all copyright, patent, trademark, and
          attribution notices from the Source form of the Work,
          excluding those notices that do not pertain to any part of
          the Derivative Works; and
 
      (d) If the Work includes a "NOTICE" text file as part of its
          distribution, then any Derivative Works that You distribute must
          include a readable copy of the attribution notices contained
          within such NOTICE file, excluding those notices that do not
          pertain to any part of the Derivative Works, in at least one
          of the following places: within a NOTICE text file distributed
          as part of the Derivative Works; within the Source form or
          documentation, if provided along with the Derivative Works; or,
          within a display generated by the Derivative Works, if and
          wherever such third-party notices normally appear. The contents
          of the NOTICE file are for informational purposes only and
          do not modify the License. You may add Your own attribution
          notices within Derivative Works that You distribute, alongside
          or as an addendum to the NOTICE text from the Work, provided
          that such additional attribution notices cannot be construed
          as modifying the License.
 
      You may add Your own copyright statement to Your modifications and
      may provide additional or different license terms and conditions
      for use, reproduction, or distribution of Your modifications, or
      for any such Derivative Works as a whole, provided Your use,
      reproduction, and distribution of the Work otherwise complies with
      the conditions stated in this License.
 
   5. Submission of Contributions. Unless You explicitly state otherwise,
      any Contribution intentionally submitted for inclusion in the Work
      by You to the Licensor shall be under the terms and conditions of
      this License, without any additional terms or conditions.
      Notwithstanding the above, nothing herein shall supersede or modify
      the terms of any separate license agreement you may have executed
      with Licensor regarding such Contributions.
 
   6. Trademarks. This License does not grant permission to use the trade
      names, trademarks, service marks, or product names of the Licensor,
      except as required for reasonable and customary use in describing the
      origin of the Work and reproducing the content of the NOTICE file.
 
   7. Disclaimer of Warranty. Unless required by applicable law or
      agreed to in writing, Licensor provides the Work (and each
      Contributor provides its Contributions) on an "AS IS" BASIS,
      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
      implied, including, without limitation, any warranties or conditions
      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
      PARTICULAR PURPOSE. You are solely responsible for determining the
      appropriateness of using or redistributing the Work and assume any
      risks associated with Your exercise of permissions under this License.
 
   8. Limitation of Liability. In no event and under no legal theory,
      whether in tort (including negligence), contract, or otherwise,
      unless required by applicable law (such as deliberate and grossly
      negligent acts) or agreed to in writing, shall any Contributor be
      liable to You for damages, including any direct, indirect, special,
      incidental, or consequential damages of any character arising as a
      result of this License or out of the use or inability to use the
      Work (including but not limited to damages for loss of goodwill,
      work stoppage, computer failure or malfunction, or any and all
      other commercial damages or losses), even if such Contributor
      has been advised of the possibility of such damages.
 
   9. Accepting Warranty or Additional Liability. While redistributing
      the Work or Derivative Works thereof, You may choose to offer,
      and charge a fee for, acceptance of support, warranty, indemnity,
      or other liability obligations and/or rights consistent with this
      License. However, in accepting such obligations, You may act only
      on Your own behalf and on Your sole responsibility, not on behalf
      of any other Contributor, and only if You agree to indemnify,
      defend, and hold each Contributor harmless for any liability
      incurred by, or claims asserted against, such Contributor by reason
      of your accepting any such warranty or additional liability.
 
   END OF TERMS AND CONDITIONS
 
   APPENDIX: How to apply the Apache License to your work.
 
      To apply the Apache License to your work, attach the following
      boilerplate notice, with the fields enclosed by brackets "{}"
      replaced with your own identifying information. (Don't include
      the brackets!)  The text should be enclosed in the appropriate
      comment syntax for the file format. We also recommend that a
      file or class name and description of purpose be included on the
      same "printed page" as the copyright notice for easier
      identification within third-party archives.
 
   Copyright {yyyy} {name of copyright owner}
 
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at
 
       http://www.apache.org/licenses/LICENSE-2.0
 
   Unless required by applicable law or agreed to in writing, software 
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

Apache 许可证

2.0 版本，2004年1月

http://www.apache.org/licenses/

有关使用、复制和分发的条款和条件

1. 定义

“许可证”是指由本文件第1至9节关于使用、复制和分发的条款和条件定义。

“许可人”是指进行本许可证授权行为的版权所有者或由版权所有者授权的实体。

“法定实体”是指实施（代理）实体与控制该实体、受其控制或与之实行共同控制的所有其他实体的统称。为本定义的目的，“控制”是指（i）由合同或其他方式约定的，可以直接或间接指导或管理（影响）该实体的权力，或（ii）拥有50%及以上已发行股份的所有权，或（iii）该实体的实益所有权。

“您”（或“您的”）表示行使本许可授权（行为）的个人或法定实体。

“源”形式是指进行修改的首选形式，包括但不限于软件源代码，文档源和配置文件。

“对象”形式是指对源形式机械转换或翻译产生的任何形式，包括但不限于编译对象代码，生成的文档以及对其他媒体类型的转换。

“作品”是指按照本许可证提供的以源形式或对象形式的著作权作品，其中包含或附加版权通知（示例请见附录）。

“衍生作品”是指基于作品（或衍生自作品）的源形式或对象形式的任何作品。对作品的编辑修订、注释、阐述或其他修改，作为一个整体，也被视为是具有著作权的作品。为本许可证的目的，衍生作品不得包括与作品和衍生作品可分离的部分，也不得包括仅与作品和衍生作品的界面相关（或仅以名称相关联）的作品。

“贡献”是指任何著作权作品，包括作品的原始版本，以及由版权所有者、个人或由著作权人授权的法定实体代表向许可人有意提交的，对该作品或其衍生作品的任何修改或添加。就本定义而言，“提交”是指向许可人或其代理发送的任何形式的电子、口头或书面信函，包括但不限于为讨论和改进作品而由许可人管理或代表许可人设立的电子邮件列表、源代码控制系统和发布跟踪系统中的通信，但不包括版权所有者以书面形式明确标注或以其他方式特别注明的“非贡献”的通信。

“贡献者”是指许可人和任何提交贡献的个人或法律实体，其贡献需被许可人纳入作品。

2. 版权许可的授予。根据本许可证的条款和条件，每位贡献者特此授予您永久、全球、非排他性、免费、免版税、不可撤销的版权许可，用于复制，准备衍生作品，公开展示，公开表演，再许可和分发源形式或对象形式的作品和衍生作品。

3. 专利许可的授予。根据本许可证的条款和条件，每位贡献者特此授予您永久，全球，非排他性，免费，免版税，不可撤销（本条声明排除的除外）的专利许可，用于制作，委托制作，许诺销售，销售，进口和转让，凡该等许可只适用于可许的专利权利要求，且必然会被贡献者单独或联合提交的贡献侵权。如果您针对任何实体（包括诉讼中的交叉索赔或反诉讼）提起专利诉讼，指称作品或纳入作品的贡献构成直接或共同侵权，则根据本许可证授予您的任何专利许可自诉讼提起之日终止。

4. 重新分发。您可在任何媒介中复制和分发作品或衍生作品之副本，无论是否修订，还是以源形式或对象形式，条件是您需要满足下列条款：
(a) 您必须为作品或衍生作品的任何其他接收者提供本许可证的副本；并且
(b) 您必须让任何修改过的文件附带明显的声明，声明您已更改文件；并且
(c) 您必须在您分发的衍生作品的源形式中保留所有版权、专利、商标和属性声明，但不包括不属于衍生作品任何部分的类似声明；并且
(d) 如果作品将本“通知”文本文件作为其分发作品的一部分，那么您分发的任何衍生作品中也须至少在下列地方之一包含，在这样的通知文件中所包含的属性声明的可读副本，但不包括那些不属于衍生作品任何部分的通知：在作为衍生作品一部分而分发的通知文本文件中；如果与衍生作品一起提供，则在源程序形式或文件中；或者通常作为第三方通知出现的时候和地方，在衍生作品中产生的画面中。通知文件的内容仅供信息提供，并不构成对许可证的修改。您可在您分发的衍生作品中，在作品的通知文本后或作为附录添加自己的属性通知，条件是附加的属性通知不得构成本许可证的修改。

您可以为您的修订添加自己的版权声明，也可就如何使用、复制或分发您的修改或类似的衍生作品提供附加的或不同的条款，条件是您对作品的使用、复制和分发必须符合本许可证中声明的条款。

5. 贡献的提交。除非您明确声明，在作品中由您向许可证颁发者的提交的，用于合并到作品的贡献，必须在无任何附加条款下符合本许可证的条款。尽管如此，本协议不得取代或修改，您和许可人就提交的贡献而单独签署的任何许可协议的条款。

6. 商标。本许可证并未授权您使用许可证颁发者的商号、商标、服务标记或产品名称，除非将这些名称用于合理性和惯例性描述作品来源和复制通知文件的内容时。

7. 免责声明。非因法律要求或经书面同意，许可人以“按原样”基础提供作品（并且每个贡献者提供其贡献），无任何明示的或暗示的保证或条件，包括但不限于关于所有权、不侵权、商品适销性、或适用性的保证或条件。您完全负责确定使用或分发作品的适当性，并承担与您在本许可证下行使权限相关的任何风险。

8. 责任限制条款。在任何情况下并根据任何法律，无论是因侵权（包括过失）或根据合同，还是其它原因，除非根据适用法律需要（例如故意行为和重大过失行为）或经书面同意，即使贡献者事先已被告知发生损害的可能性，任何贡献者不就您因使用本许可证或不能使用或无法使用作品（包括但不限于商誉损失、停工、计算机失效或故障，或任何商业损坏或损失）而造成的损失，包括直接的、非直接的、特殊的、意外的或间接的字符损坏而负责。

9. 接受保证或附加责任。重新分发作品或及其衍生作品时，您可选择在本许可证条款下承担支持、担保、赔偿或其它职责义务和/或权利，并收取费用。但是，在承担上述义务时，您只可代表您本身并自行承担责任，不可代表任何其它贡献者，只要您同意，赔偿，捍卫和保持每个贡献者对由于您接受任何此类保证或附加责任而引起的任何责任。

条款结束

附录：如何在您的作品中应用 Apache 许可证。

若要向在作品中应用 Apache 许可证，请附加下列声明模板，将括号“{}“中的字段替换为您自己的个人信息（不包括括号本身）。文本必须以适当的注释句法包含在文本文件中。另外建议将文件名或类别名，以及目的说明，包含在“可打印版本”的版权通知页同页，以方便和第三方内容相区别。

版权所有 {年份} {作者}

根据 Apache 许可证 2.0 版（“许可证”）许可； 若非遵从本许可证，您不得使用本文件。 您可以从以下途径获得许可证的副本

http://www.apache.org/licenses/LICENSE-2.0

除非法律要求或经书面同意，根据许可证分发的软件以“按原样”基础分发， 不附带任何明示或暗示的保证或条件。有关许可证下的权限和限制，请参阅许可证。

全部或部分免费下载和使用基于 Apache 许可证的软件，用于个人，公司内部或商业目的; 在您创建的软件包或发行版中使用基于 Apache 许可证的软件。

在您可能进行的任何重新分发中包括许可证的副本; 为Apache软件基金会提供任何包含Apache软件的发行版的明确归因。

Apache 软体基金会与自由软体基金会都同意 Apache 许可证属于自由软体许可证，且相容于第三版的 GNU 通用公共许可证，但第一版与第二版的GNU通用公共许可证并不相容于 Apache 许可证。

点击下载上述的许可文本，放置在源代码的根目录中，或手动创建一个文本文件（通常命名为 LICENSE 或 LICENSE.txt），并将许可证的文本复制到文件中。注意将{年份}替换为当前年份，{作者}用版权持有人的姓名（或名称）替换。

提示：Apache 基金会建议另将声明模板添加到每个源文件的开头部分。您可以在许可证附录部分找到声明模板。

可选: 将 Apache 许可信息添加到你的软件描述信息中，(例如, Node.js, Ruby, 和 Rust)。 这可以让别人明确了解该软件是遵循哪种协议发布的。