diff --git a/LICENSE.txt b/LICENSE.txt new file mode 100644 --- /dev/null +++ b/LICENSE.txt @@ -0,0 +1,661 @@ + GNU AFFERO GENERAL PUBLIC LICENSE + Version 3, 19 November 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU Affero General Public License is a free, copyleft license for +software and other kinds of works, specifically designed to ensure +cooperation with the community in the case of network server software. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +our General Public Licenses are intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. + + When we speak of free software, we are referring to freedom, not +price. Our General Public Licenses are designed to make sure that you +have the freedom to distribute copies of free software (and charge for +them if you wish), that you receive source code or can get it if you +want it, that you can change the software or use pieces of it in new +free programs, and that you know you can do these things. + + Developers that use our General Public Licenses protect your rights +with two steps: (1) assert copyright on the software, and (2) offer +you this License which gives you legal permission to copy, distribute +and/or modify the software. + + A secondary benefit of defending all users' freedom is that +improvements made in alternate versions of the program, if they +receive widespread use, become available for other developers to +incorporate. Many developers of free software are heartened and +encouraged by the resulting cooperation. However, in the case of +software used on network servers, this result may fail to come about. +The GNU General Public License permits making a modified version and +letting the public access it on a server without ever releasing its +source code to the public. + + The GNU Affero General Public License is designed specifically to +ensure that, in such cases, the modified source code becomes available +to the community. It requires the operator of a network server to +provide the source code of the modified version running there to the +users of that server. Therefore, public use of a modified version, on +a publicly accessible server, gives the public access to the source +code of the modified version. + + An older license, called the Affero General Public License and +published by Affero, was designed to accomplish similar goals. This is +a different license, not a version of the Affero GPL, but Affero has +released a new version of the Affero GPL which permits relicensing under +this license. + + The precise terms and conditions for copying, distribution and +modification follow. + + TERMS AND CONDITIONS + + 0. Definitions. + + "This License" refers to version 3 of the GNU Affero General Public License. + + "Copyright" also means copyright-like laws that apply to other kinds of +works, such as semiconductor masks. + + "The Program" refers to any copyrightable work licensed under this +License. Each licensee is addressed as "you". "Licensees" and +"recipients" may be individuals or organizations. + + To "modify" a work means to copy from or adapt all or part of the work +in a fashion requiring copyright permission, other than the making of an +exact copy. The resulting work is called a "modified version" of the +earlier work or a work "based on" the earlier work. + + A "covered work" means either the unmodified Program or a work based +on the Program. + + To "propagate" a work means to do anything with it that, without +permission, would make you directly or secondarily liable for +infringement under applicable copyright law, except executing it on a +computer or modifying a private copy. Propagation includes copying, +distribution (with or without modification), making available to the +public, and in some countries other activities as well. + + To "convey" a work means any kind of propagation that enables other +parties to make or receive copies. Mere interaction with a user through +a computer network, with no transfer of a copy, is not conveying. + + An interactive user interface displays "Appropriate Legal Notices" +to the extent that it includes a convenient and prominently visible +feature that (1) displays an appropriate copyright notice, and (2) +tells the user that there is no warranty for the work (except to the +extent that warranties are provided), that licensees may convey the +work under this License, and how to view a copy of this License. If +the interface presents a list of user commands or options, such as a +menu, a prominent item in the list meets this criterion. + + 1. Source Code. + + The "source code" for a work means the preferred form of the work +for making modifications to it. "Object code" means any non-source +form of a work. + + A "Standard Interface" means an interface that either is an official +standard defined by a recognized standards body, or, in the case of +interfaces specified for a particular programming language, one that +is widely used among developers working in that language. + + The "System Libraries" of an executable work include anything, other +than the work as a whole, that (a) is included in the normal form of +packaging a Major Component, but which is not part of that Major +Component, and (b) serves only to enable use of the work with that +Major Component, or to implement a Standard Interface for which an +implementation is available to the public in source code form. A +"Major Component", in this context, means a major essential component +(kernel, window system, and so on) of the specific operating system +(if any) on which the executable work runs, or a compiler used to +produce the work, or an object code interpreter used to run it. + + The "Corresponding Source" for a work in object code form means all +the source code needed to generate, install, and (for an executable +work) run the object code and to modify the work, including scripts to +control those activities. However, it does not include the work's +System Libraries, or general-purpose tools or generally available free +programs which are used unmodified in performing those activities but +which are not part of the work. For example, Corresponding Source +includes interface definition files associated with source files for +the work, and the source code for shared libraries and dynamically +linked subprograms that the work is specifically designed to require, +such as by intimate data communication or control flow between those +subprograms and other parts of the work. + + The Corresponding Source need not include anything that users +can regenerate automatically from other parts of the Corresponding +Source. + + The Corresponding Source for a work in source code form is that +same work. + + 2. Basic Permissions. + + All rights granted under this License are granted for the term of +copyright on the Program, and are irrevocable provided the stated +conditions are met. This License explicitly affirms your unlimited +permission to run the unmodified Program. The output from running a +covered work is covered by this License only if the output, given its +content, constitutes a covered work. This License acknowledges your +rights of fair use or other equivalent, as provided by copyright law. + + You may make, run and propagate covered works that you do not +convey, without conditions so long as your license otherwise remains +in force. You may convey covered works to others for the sole purpose +of having them make modifications exclusively for you, or provide you +with facilities for running those works, provided that you comply with +the terms of this License in conveying all material for which you do +not control copyright. Those thus making or running the covered works +for you must do so exclusively on your behalf, under your direction +and control, on terms that prohibit them from making any copies of +your copyrighted material outside their relationship with you. + + Conveying under any other circumstances is permitted solely under +the conditions stated below. Sublicensing is not allowed; section 10 +makes it unnecessary. + + 3. Protecting Users' Legal Rights From Anti-Circumvention Law. + + No covered work shall be deemed part of an effective technological +measure under any applicable law fulfilling obligations under article +11 of the WIPO copyright treaty adopted on 20 December 1996, or +similar laws prohibiting or restricting circumvention of such +measures. + + When you convey a covered work, you waive any legal power to forbid +circumvention of technological measures to the extent such circumvention +is effected by exercising rights under this License with respect to +the covered work, and you disclaim any intention to limit operation or +modification of the work as a means of enforcing, against the work's +users, your or third parties' legal rights to forbid circumvention of +technological measures. + + 4. Conveying Verbatim Copies. + + You may convey verbatim copies of the Program's source code as you +receive it, in any medium, provided that you conspicuously and +appropriately publish on each copy an appropriate copyright notice; +keep intact all notices stating that this License and any +non-permissive terms added in accord with section 7 apply to the code; +keep intact all notices of the absence of any warranty; and give all +recipients a copy of this License along with the Program. + + You may charge any price or no price for each copy that you convey, +and you may offer support or warranty protection for a fee. + + 5. Conveying Modified Source Versions. + + You may convey a work based on the Program, or the modifications to +produce it from the Program, in the form of source code under the +terms of section 4, provided that you also meet all of these conditions: + + a) The work must carry prominent notices stating that you modified + it, and giving a relevant date. + + b) The work must carry prominent notices stating that it is + released under this License and any conditions added under section + 7. This requirement modifies the requirement in section 4 to + "keep intact all notices". + + c) You must license the entire work, as a whole, under this + License to anyone who comes into possession of a copy. This + License will therefore apply, along with any applicable section 7 + additional terms, to the whole of the work, and all its parts, + regardless of how they are packaged. This License gives no + permission to license the work in any other way, but it does not + invalidate such permission if you have separately received it. + + d) If the work has interactive user interfaces, each must display + Appropriate Legal Notices; however, if the Program has interactive + interfaces that do not display Appropriate Legal Notices, your + work need not make them do so. + + A compilation of a covered work with other separate and independent +works, which are not by their nature extensions of the covered work, +and which are not combined with it such as to form a larger program, +in or on a volume of a storage or distribution medium, is called an +"aggregate" if the compilation and its resulting copyright are not +used to limit the access or legal rights of the compilation's users +beyond what the individual works permit. Inclusion of a covered work +in an aggregate does not cause this License to apply to the other +parts of the aggregate. + + 6. Conveying Non-Source Forms. + + You may convey a covered work in object code form under the terms +of sections 4 and 5, provided that you also convey the +machine-readable Corresponding Source under the terms of this License, +in one of these ways: + + a) Convey the object code in, or embodied in, a physical product + (including a physical distribution medium), accompanied by the + Corresponding Source fixed on a durable physical medium + customarily used for software interchange. + + b) Convey the object code in, or embodied in, a physical product + (including a physical distribution medium), accompanied by a + written offer, valid for at least three years and valid for as + long as you offer spare parts or customer support for that product + model, to give anyone who possesses the object code either (1) a + copy of the Corresponding Source for all the software in the + product that is covered by this License, on a durable physical + medium customarily used for software interchange, for a price no + more than your reasonable cost of physically performing this + conveying of source, or (2) access to copy the + Corresponding Source from a network server at no charge. + + c) Convey individual copies of the object code with a copy of the + written offer to provide the Corresponding Source. This + alternative is allowed only occasionally and noncommercially, and + only if you received the object code with such an offer, in accord + with subsection 6b. + + d) Convey the object code by offering access from a designated + place (gratis or for a charge), and offer equivalent access to the + Corresponding Source in the same way through the same place at no + further charge. You need not require recipients to copy the + Corresponding Source along with the object code. If the place to + copy the object code is a network server, the Corresponding Source + may be on a different server (operated by you or a third party) + that supports equivalent copying facilities, provided you maintain + clear directions next to the object code saying where to find the + Corresponding Source. Regardless of what server hosts the + Corresponding Source, you remain obligated to ensure that it is + available for as long as needed to satisfy these requirements. + + e) Convey the object code using peer-to-peer transmission, provided + you inform other peers where the object code and Corresponding + Source of the work are being offered to the general public at no + charge under subsection 6d. + + A separable portion of the object code, whose source code is excluded +from the Corresponding Source as a System Library, need not be +included in conveying the object code work. + + A "User Product" is either (1) a "consumer product", which means any +tangible personal property which is normally used for personal, family, +or household purposes, or (2) anything designed or sold for incorporation +into a dwelling. In determining whether a product is a consumer product, +doubtful cases shall be resolved in favor of coverage. For a particular +product received by a particular user, "normally used" refers to a +typical or common use of that class of product, regardless of the status +of the particular user or of the way in which the particular user +actually uses, or expects or is expected to use, the product. A product +is a consumer product regardless of whether the product has substantial +commercial, industrial or non-consumer uses, unless such uses represent +the only significant mode of use of the product. + + "Installation Information" for a User Product means any methods, +procedures, authorization keys, or other information required to install +and execute modified versions of a covered work in that User Product from +a modified version of its Corresponding Source. The information must +suffice to ensure that the continued functioning of the modified object +code is in no case prevented or interfered with solely because +modification has been made. + + If you convey an object code work under this section in, or with, or +specifically for use in, a User Product, and the conveying occurs as +part of a transaction in which the right of possession and use of the +User Product is transferred to the recipient in perpetuity or for a +fixed term (regardless of how the transaction is characterized), the +Corresponding Source conveyed under this section must be accompanied +by the Installation Information. But this requirement does not apply +if neither you nor any third party retains the ability to install +modified object code on the User Product (for example, the work has +been installed in ROM). + + The requirement to provide Installation Information does not include a +requirement to continue to provide support service, warranty, or updates +for a work that has been modified or installed by the recipient, or for +the User Product in which it has been modified or installed. Access to a +network may be denied when the modification itself materially and +adversely affects the operation of the network or violates the rules and +protocols for communication across the network. + + Corresponding Source conveyed, and Installation Information provided, +in accord with this section must be in a format that is publicly +documented (and with an implementation available to the public in +source code form), and must require no special password or key for +unpacking, reading or copying. + + 7. Additional Terms. + + "Additional permissions" are terms that supplement the terms of this +License by making exceptions from one or more of its conditions. +Additional permissions that are applicable to the entire Program shall +be treated as though they were included in this License, to the extent +that they are valid under applicable law. If additional permissions +apply only to part of the Program, that part may be used separately +under those permissions, but the entire Program remains governed by +this License without regard to the additional permissions. + + When you convey a copy of a covered work, you may at your option +remove any additional permissions from that copy, or from any part of +it. (Additional permissions may be written to require their own +removal in certain cases when you modify the work.) You may place +additional permissions on material, added by you to a covered work, +for which you have or can give appropriate copyright permission. + + Notwithstanding any other provision of this License, for material you +add to a covered work, you may (if authorized by the copyright holders of +that material) supplement the terms of this License with terms: + + a) Disclaiming warranty or limiting liability differently from the + terms of sections 15 and 16 of this License; or + + b) Requiring preservation of specified reasonable legal notices or + author attributions in that material or in the Appropriate Legal + Notices displayed by works containing it; or + + c) Prohibiting misrepresentation of the origin of that material, or + requiring that modified versions of such material be marked in + reasonable ways as different from the original version; or + + d) Limiting the use for publicity purposes of names of licensors or + authors of the material; or + + e) Declining to grant rights under trademark law for use of some + trade names, trademarks, or service marks; or + + f) Requiring indemnification of licensors and authors of that + material by anyone who conveys the material (or modified versions of + it) with contractual assumptions of liability to the recipient, for + any liability that these contractual assumptions directly impose on + those licensors and authors. + + All other non-permissive additional terms are considered "further +restrictions" within the meaning of section 10. If the Program as you +received it, or any part of it, contains a notice stating that it is +governed by this License along with a term that is a further +restriction, you may remove that term. If a license document contains +a further restriction but permits relicensing or conveying under this +License, you may add to a covered work material governed by the terms +of that license document, provided that the further restriction does +not survive such relicensing or conveying. + + If you add terms to a covered work in accord with this section, you +must place, in the relevant source files, a statement of the +additional terms that apply to those files, or a notice indicating +where to find the applicable terms. + + Additional terms, permissive or non-permissive, may be stated in the +form of a separately written license, or stated as exceptions; +the above requirements apply either way. + + 8. Termination. + + You may not propagate or modify a covered work except as expressly +provided under this License. Any attempt otherwise to propagate or +modify it is void, and will automatically terminate your rights under +this License (including any patent licenses granted under the third +paragraph of section 11). + + However, if you cease all violation of this License, then your +license from a particular copyright holder is reinstated (a) +provisionally, unless and until the copyright holder explicitly and +finally terminates your license, and (b) permanently, if the copyright +holder fails to notify you of the violation by some reasonable means +prior to 60 days after the cessation. + + Moreover, your license from a particular copyright holder is +reinstated permanently if the copyright holder notifies you of the +violation by some reasonable means, this is the first time you have +received notice of violation of this License (for any work) from that +copyright holder, and you cure the violation prior to 30 days after +your receipt of the notice. + + Termination of your rights under this section does not terminate the +licenses of parties who have received copies or rights from you under +this License. If your rights have been terminated and not permanently +reinstated, you do not qualify to receive new licenses for the same +material under section 10. + + 9. Acceptance Not Required for Having Copies. + + You are not required to accept this License in order to receive or +run a copy of the Program. Ancillary propagation of a covered work +occurring solely as a consequence of using peer-to-peer transmission +to receive a copy likewise does not require acceptance. However, +nothing other than this License grants you permission to propagate or +modify any covered work. These actions infringe copyright if you do +not accept this License. Therefore, by modifying or propagating a +covered work, you indicate your acceptance of this License to do so. + + 10. Automatic Licensing of Downstream Recipients. + + Each time you convey a covered work, the recipient automatically +receives a license from the original licensors, to run, modify and +propagate that work, subject to this License. You are not responsible +for enforcing compliance by third parties with this License. + + An "entity transaction" is a transaction transferring control of an +organization, or substantially all assets of one, or subdividing an +organization, or merging organizations. If propagation of a covered +work results from an entity transaction, each party to that +transaction who receives a copy of the work also receives whatever +licenses to the work the party's predecessor in interest had or could +give under the previous paragraph, plus a right to possession of the +Corresponding Source of the work from the predecessor in interest, if +the predecessor has it or can get it with reasonable efforts. + + You may not impose any further restrictions on the exercise of the +rights granted or affirmed under this License. For example, you may +not impose a license fee, royalty, or other charge for exercise of +rights granted under this License, and you may not initiate litigation +(including a cross-claim or counterclaim in a lawsuit) alleging that +any patent claim is infringed by making, using, selling, offering for +sale, or importing the Program or any portion of it. + + 11. Patents. + + A "contributor" is a copyright holder who authorizes use under this +License of the Program or a work on which the Program is based. The +work thus licensed is called the contributor's "contributor version". + + A contributor's "essential patent claims" are all patent claims +owned or controlled by the contributor, whether already acquired or +hereafter acquired, that would be infringed by some manner, permitted +by this License, of making, using, or selling its contributor version, +but do not include claims that would be infringed only as a +consequence of further modification of the contributor version. For +purposes of this definition, "control" includes the right to grant +patent sublicenses in a manner consistent with the requirements of +this License. + + Each contributor grants you a non-exclusive, worldwide, royalty-free +patent license under the contributor's essential patent claims, to +make, use, sell, offer for sale, import and otherwise run, modify and +propagate the contents of its contributor version. + + In the following three paragraphs, a "patent license" is any express +agreement or commitment, however denominated, not to enforce a patent +(such as an express permission to practice a patent or covenant not to +sue for patent infringement). To "grant" such a patent license to a +party means to make such an agreement or commitment not to enforce a +patent against the party. + + If you convey a covered work, knowingly relying on a patent license, +and the Corresponding Source of the work is not available for anyone +to copy, free of charge and under the terms of this License, through a +publicly available network server or other readily accessible means, +then you must either (1) cause the Corresponding Source to be so +available, or (2) arrange to deprive yourself of the benefit of the +patent license for this particular work, or (3) arrange, in a manner +consistent with the requirements of this License, to extend the patent +license to downstream recipients. "Knowingly relying" means you have +actual knowledge that, but for the patent license, your conveying the +covered work in a country, or your recipient's use of the covered work +in a country, would infringe one or more identifiable patents in that +country that you have reason to believe are valid. + + If, pursuant to or in connection with a single transaction or +arrangement, you convey, or propagate by procuring conveyance of, a +covered work, and grant a patent license to some of the parties +receiving the covered work authorizing them to use, propagate, modify +or convey a specific copy of the covered work, then the patent license +you grant is automatically extended to all recipients of the covered +work and works based on it. + + A patent license is "discriminatory" if it does not include within +the scope of its coverage, prohibits the exercise of, or is +conditioned on the non-exercise of one or more of the rights that are +specifically granted under this License. You may not convey a covered +work if you are a party to an arrangement with a third party that is +in the business of distributing software, under which you make payment +to the third party based on the extent of your activity of conveying +the work, and under which the third party grants, to any of the +parties who would receive the covered work from you, a discriminatory +patent license (a) in connection with copies of the covered work +conveyed by you (or copies made from those copies), or (b) primarily +for and in connection with specific products or compilations that +contain the covered work, unless you entered into that arrangement, +or that patent license was granted, prior to 28 March 2007. + + Nothing in this License shall be construed as excluding or limiting +any implied license or other defenses to infringement that may +otherwise be available to you under applicable patent law. + + 12. No Surrender of Others' Freedom. + + If conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot convey a +covered work so as to satisfy simultaneously your obligations under this +License and any other pertinent obligations, then as a consequence you may +not convey it at all. For example, if you agree to terms that obligate you +to collect a royalty for further conveying from those to whom you convey +the Program, the only way you could satisfy both those terms and this +License would be to refrain entirely from conveying the Program. + + 13. Remote Network Interaction; Use with the GNU General Public License. + + Notwithstanding any other provision of this License, if you modify the +Program, your modified version must prominently offer all users +interacting with it remotely through a computer network (if your version +supports such interaction) an opportunity to receive the Corresponding +Source of your version by providing access to the Corresponding Source +from a network server at no charge, through some standard or customary +means of facilitating copying of software. This Corresponding Source +shall include the Corresponding Source for any work covered by version 3 +of the GNU General Public License that is incorporated pursuant to the +following paragraph. + + Notwithstanding any other provision of this License, you have +permission to link or combine any covered work with a work licensed +under version 3 of the GNU General Public License into a single +combined work, and to convey the resulting work. The terms of this +License will continue to apply to the part which is the covered work, +but the work with which it is combined will remain governed by version +3 of the GNU General Public License. + + 14. Revised Versions of this License. + + The Free Software Foundation may publish revised and/or new versions of +the GNU Affero General Public License from time to time. Such new versions +will be similar in spirit to the present version, but may differ in detail to +address new problems or concerns. + + Each version is given a distinguishing version number. If the +Program specifies that a certain numbered version of the GNU Affero General +Public License "or any later version" applies to it, you have the +option of following the terms and conditions either of that numbered +version or of any later version published by the Free Software +Foundation. If the Program does not specify a version number of the +GNU Affero General Public License, you may choose any version ever published +by the Free Software Foundation. + + If the Program specifies that a proxy can decide which future +versions of the GNU Affero General Public License can be used, that proxy's +public statement of acceptance of a version permanently authorizes you +to choose that version for the Program. + + Later license versions may give you additional or different +permissions. However, no additional obligations are imposed on any +author or copyright holder as a result of your choosing to follow a +later version. + + 15. Disclaimer of Warranty. + + THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY +APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT +HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY +OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, +THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM +IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF +ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + + 16. Limitation of Liability. + + IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS +THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY +GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE +USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF +DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD +PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), +EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF +SUCH DAMAGES. + + 17. Interpretation of Sections 15 and 16. + + If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +state the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If your software can interact with users remotely through a computer +network, you should also make sure that it provides a way for users to +get its source. For example, if your program is a web application, its +interface could display a "Source" link that leads users to an archive +of the code. There are many ways you could offer source, and different +solutions will be better for different programs; see section 13 for the +specific requirements. + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU AGPL, see +. diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/data/pg-harness.ini b/data/pg-harness.ini new file mode 100644 --- /dev/null +++ b/data/pg-harness.ini @@ -0,0 +1,30 @@ +[rest] +listenPort=8900 + +[postgresql] +# User/password combination which the daemon will use to create/drop databases +user=pg-harness +password=pg-harness +# Database that the administrative user will connect to when creating/dropping +# databases. This database MUST exist, but will NOT be modified in any way. +database=postgres +# Note that the host name is returned without translation +# in the REST interface, so you'll want to use a FQDN. +host=localhost +# Port that your PostgreSQL instance is listening on. +port=5432 +# User/password combination which the daemon will return for the +# test database. The test user will be the owner of all temporary +# databases that are created. +testUser=pg-harness-test +testPassword=pg-harness-test +# Template database to use for stamping out temporary databases. +# It is recommended that you use either a) an empty template, or +# b) a snapshot of your production schema from the last production +# release. (The latter will help you test out any schema migrations +# you may have pending for the next release.) +templateDatabase=template1 +# Duration for temporary databases. All existing connections +# to the temporary database will be killed and the database will +# be dropped after this amount of time. +durationSeconds=300 diff --git a/pg-harness-server.cabal b/pg-harness-server.cabal new file mode 100644 --- /dev/null +++ b/pg-harness-server.cabal @@ -0,0 +1,45 @@ +Name: pg-harness-server +Version: 0.3.0 +Synopsis: REST service for creating temporary PostgreSQL databases +Description: + REST service for conveniently creating temporary PostgreSQL databases + for use in tests. + . + See for + detailed usage and setup instructions. +License: AGPL-3 +License-file: LICENSE.txt +Author: Bardur Arantsson +Homepage: https://github.com/BardurArantsson/pg-harness +Maintainer: bardur@scientician.net +Copyright: Copyright (c) 2014, 2015 Bardur Arantsson +Category: Database Testing Web +Build-type: Simple +Cabal-version: >=1.10 +Data-dir: data +Data-files: pg-harness.ini + +Source-repository head + type: git + location: https://github.com/BardurArantsson/pg-harness.git + +Executable pg-harness + Main-is: Main.hs + Ghc-options: -Wall + Build-depends: base == 4.* + , async >= 2.0.1.5 && < 3 + , ini >= 0.2 && < 0.3 + , postgresql-simple >= 0.4.2 && < 0.5 + , random >= 1.0 && < 1.2 + , scotty >= 0.7.0 && < 0.10 + , text >= 1.1.0 && < 2 + , transformers >= 0.4.1 && < 0.5 + Default-extensions: LambdaCase + OverloadedStrings + ScopedTypeVariables + Hs-source-dirs: src + Default-language: Haskell2010 + Other-modules: Paths_pg_harness_server + PgHarness.Configuration + PgHarness.Mutex + PgHarness.DatabaseId diff --git a/src/Main.hs b/src/Main.hs new file mode 100644 --- /dev/null +++ b/src/Main.hs @@ -0,0 +1,158 @@ +{- + pg-harness, REST service for creating temporary PostgreSQL databases. + Copyright (C) 2014, 2015 Bardur Arantsson + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . +-} +module Main ( main ) where + +import Control.Concurrent (threadDelay) +import Control.Concurrent.Async (async, withAsync, waitCatch) +import Control.Exception (bracket) +import Control.Monad (void) +import Control.Monad.Trans.Class (lift) +import Data.String (fromString) +import qualified Data.Text.Lazy as TL +import Database.PostgreSQL.Simple (Connection, ConnectInfo(..), Only(..)) +import qualified Database.PostgreSQL.Simple as P +import System.IO (stderr, hPutStrLn) +import System.Random (randomRIO) +import Web.Scotty (scotty, post, text, ScottyM, raise) +import Paths_pg_harness_server (getDataFileName) +import PgHarness.Mutex +import PgHarness.Configuration +import PgHarness.DatabaseId + +-- Perform an operation with an open connection to the database. +-- The connection will automatically be closed after the operation +-- completes, regardless of whether it completes successfully or +-- not (e.g. if there's an exception). +withConnection :: Configuration -> (Connection -> IO a) -> IO a +withConnection configuration action = bracket (P.connect connectInfo) P.close action + where + connectInfo = ConnectInfo + { connectHost = cfgHost configuration + , connectPort = cfgPort configuration + , connectUser = cfgUser configuration + , connectPassword = cfgPassword configuration + , connectDatabase = unquotedIdentifier (cfgDatabase configuration) + } + +-- Create a random valid PostgreSQL identifier. +mkRandomIdent :: IO String +mkRandomIdent = do + h <- chooseElement letters + t <- sequence $ replicate 32 $ chooseElement lettersAndDigits + return (h:t) + where + letters = "abcdefhijklmnopqrstuvwxyz" + digits = "0123456789" + lettersAndDigits = letters ++ digits + chooseElement t = do + i <- randomRIO (0, length t - 1) + return $ t !! i + +-- Create temporary database ID. +mkTemporaryDatabaseId :: IO (Either String DatabaseId) +mkTemporaryDatabaseId = fmap mkDatabaseId $ fmap ("temp_" ++) mkRandomIdent + +-- Create temporary database and return its name. +createTemporaryDatabase :: Configuration -> DatabaseId -> IO () +createTemporaryDatabase configuration databaseId = do + -- Connect to the administrative database. + withConnection configuration $ \connection -> do + -- Create the temporary database. + void $ P.execute_ connection $ createSql + putStrLn $ "Created temporary database: " ++ sqlDatabaseId + -- Spawn a thread to kill the database after a certain delay. + void $ async $ do + threadDelay $ (cfgDurationSeconds configuration) * 1000000 + dropDatabase configuration databaseId + where + createSql = fromString $ + "CREATE DATABASE " ++ sqlDatabaseId ++ + " WITH TEMPLATE " ++ (sqlIdentifier $ cfgTemplateDatabase configuration) ++ + " OWNER \"" ++ (cfgTestUser configuration) ++ "\"" + + sqlDatabaseId = sqlIdentifier databaseId + +dropDatabase :: Configuration -> DatabaseId -> IO () +dropDatabase configuration databaseId = + -- Since this is running in a separate thread we need explicit + -- exception handling to avoid silent exceptions. + withAsync doDropDatabase waitCatch >>= \case + Left exc -> hPutStrLn stderr $ "Exception occurred while creating temporary database: " ++ show exc + Right _ -> return () + where + doDropDatabase = withConnection configuration $ \connection -> do + -- We need to block new connections to the temporary database; otherwise + -- a reconnect during the destruction could foil our attempt to drop. + void $ P.execute_ connection blockConnectionsSql + -- Now we can kill the backends, i.e. terminate all the connections. No + -- new connections can be created because of the previous block. + P.forEach_ connection terminateConnectionsSql $ \(Only (_::Bool)) -> return () + -- Finally, we can drop. + void $ P.execute_ connection dropSql + -- Logging + putStrLn $ "Dropped temporary database: " ++ sqlDatabaseId + + dropSql = fromString $ + "DROP DATABASE " ++ sqlDatabaseId + + blockConnectionsSql = fromString $ + "UPDATE pg_database \ + \ SET datallowconn = FALSE \ + \ WHERE datname = '" ++ sqlDatabaseId ++ "'" + + terminateConnectionsSql = fromString $ + "SELECT pg_terminate_backend(pid) \ + \ FROM pg_stat_activity \ + \ WHERE pid <> pg_backend_pid() \ + \ AND datname = '" ++ sqlDatabaseId ++ "'" + + sqlDatabaseId = sqlIdentifier databaseId + +-- REST interface +routes :: Configuration -> ScottyM () +routes configuration = do + -- Mutex to prevent multiple "create" requests from being + -- processed simultaneously; PostgreSQL cannot handle + -- "cloning" a template concurrently. + mutex <- lift $ mkMutex + -- Add all the routes. + post "/" $ do + -- Generate a name for temporary database. + lift mkTemporaryDatabaseId >>= \case + Left err -> + raise $ TL.pack err + Right databaseId -> do + -- Create the temporary database. + lift $ mutex $ createTemporaryDatabase configuration databaseId + -- Return a string with the username/password and database name. + text $ TL.pack $ + cfgTestUser configuration ++ ":" ++ cfgTestPassword configuration ++ + "@" ++ + cfgHost configuration ++ ":" ++ (show $ cfgPort configuration) ++ + "/" ++ + (unquotedIdentifier databaseId) + +main :: IO () +main = do + -- Load configuration from file. + getDataFileName "pg-harness.ini" >>= loadConfiguration >>= \case + Left msg -> hPutStrLn stderr msg + Right configuration -> do + -- Start the web serving thread + putStrLn $ "Starting with configuration: " ++ show configuration + scotty (cfgListenPort configuration) $ routes configuration diff --git a/src/PgHarness/Configuration.hs b/src/PgHarness/Configuration.hs new file mode 100644 --- /dev/null +++ b/src/PgHarness/Configuration.hs @@ -0,0 +1,77 @@ +{- + pg-harness, REST service for creating temporary PostgreSQL databases. + Copyright (C) 2014, 2015 Bardur Arantsson + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . +-} +module PgHarness.Configuration + ( Configuration(..) + , loadConfiguration + ) where + +import Data.Ini (lookupValue, readIniFile, readValue) +import qualified Data.Text as T +import Data.Text.Read (decimal) +import Data.Word (Word16) +import PgHarness.DatabaseId (mkDatabaseId, DatabaseId) + +-- Configuration for the application +data Configuration = Configuration + { cfgListenPort :: Int -- Port to listen to for REST POST requests + , cfgUser :: String -- Administrator user's user name + , cfgPassword :: String -- Administrator user's password + , cfgHost :: String -- PostgreSQL host + , cfgPort :: Word16 -- PostgreSQL port + , cfgDatabase :: DatabaseId -- Database to connect to while creating temporary database + , cfgTestUser :: String -- User to use as owner for the temporary database + , cfgTestPassword :: String -- Password to send in reply + , cfgTemplateDatabase :: DatabaseId -- Database to use as a template for the temporary database + , cfgDurationSeconds :: Int -- Duration of temporary databases + } deriving (Show) + +loadConfiguration :: FilePath -> IO (Either String Configuration) +loadConfiguration iniFilePath = do + readIniFile iniFilePath >>= \case + Left err -> return $ Left err + Right ini -> return $ do + listenPort <- readValue rest "listenPort" decimal ini + user <- lookupValue postgresql "user" ini + password <- lookupValue postgresql "password" ini + database <- lookupDatabase postgresql "database" ini + host <- lookupValue postgresql "host" ini + port <- readValue postgresql "port" decimal ini + testUser <- lookupValue postgresql "testUser" ini + testPassword <- lookupValue postgresql "testPassword" ini + templateDatabase <- lookupDatabase postgresql "templateDatabase" ini + durationSeconds <- readValue postgresql "durationSeconds" decimal ini + return $ Configuration + { cfgListenPort = listenPort + , cfgUser = T.unpack user + , cfgPassword = T.unpack password + , cfgDatabase = database + , cfgHost = T.unpack host + , cfgPort = port + , cfgTestUser = T.unpack testUser + , cfgTestPassword = T.unpack testPassword + , cfgTemplateDatabase = templateDatabase + , cfgDurationSeconds = durationSeconds + } + where + -- Read a database name from INI file + lookupDatabase section key ini = + (fmap T.unpack $ lookupValue section key ini) >>= mkDatabaseId + + -- Sections in the INI file + postgresql = "postgresql" + rest = "rest" diff --git a/src/PgHarness/DatabaseId.hs b/src/PgHarness/DatabaseId.hs new file mode 100644 --- /dev/null +++ b/src/PgHarness/DatabaseId.hs @@ -0,0 +1,63 @@ +{- + pg-harness, REST service for creating temporary PostgreSQL databases. + Copyright (C) 2014, 2015 Bardur Arantsson + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . +-} +module PgHarness.DatabaseId + ( DatabaseId + , mkDatabaseId + , sqlIdentifier + , unquotedIdentifier + ) where + +-- Newtype to prevent unsafe construction. +newtype DatabaseId = DatabaseId String + deriving (Show) + +-- Create a new database identifier. This implementation is +-- *extremely* conservative in what is accepts in the input +-- string. +mkDatabaseId :: String -> Either String DatabaseId +mkDatabaseId s = do + -- Since we don't do any quoting or anything we just need to check + -- if the string obeys all the rules. + s' <- first letters s + s'' <- rest (letters ++ digits) s' + return $ s'' `seq` DatabaseId s + where + rest :: [Char] -> String -> Either String String + rest _ [ ] = Right [ ] + rest choices (c:cs) | c `elem` choices = rest choices cs + rest _ (c:_) | otherwise = invalid c + + first :: [Char] -> String -> Either String String + first _ [ ] = Left "Database name cannot be empty" + first choices (c:cs) | c `elem` choices = Right cs + first _ (c:_) | otherwise = invalid c + + invalid c = Left $ "Invalid character '" ++ [c] ++ "' in database name '" ++ s ++ "'" + + letters = "abcdefghjiklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_" + digits = "0123456789" + +-- Turn database identifier into an SQL identifier for the +-- database. Will include quotes if necessary. +sqlIdentifier :: DatabaseId -> String +sqlIdentifier (DatabaseId s) = s -- Our whitelist ensures that we do not need any quoting. + +-- Turn database identifier into a RAW identifier for the +-- database. Will NOT include quotes! +unquotedIdentifier :: DatabaseId -> String +unquotedIdentifier (DatabaseId s) = s diff --git a/src/PgHarness/Mutex.hs b/src/PgHarness/Mutex.hs new file mode 100644 --- /dev/null +++ b/src/PgHarness/Mutex.hs @@ -0,0 +1,29 @@ +{- + pg-harness, REST service for creating temporary PostgreSQL databases. + Copyright (C) 2014, 2015 Bardur Arantsson + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . +-} +module PgHarness.Mutex ( mkMutex ) where + +import Control.Exception (bracket_) +import Control.Concurrent.QSem (newQSem, waitQSem, signalQSem) + +-- Creates a mutex based on semaphores. The mutex takes the form a +-- function which can be called with an IO action to perform that +-- action in a critical section. +mkMutex :: IO (IO a -> IO a) +mkMutex = do + mutex <- newQSem 1 + return $ \a -> bracket_ (waitQSem mutex) (signalQSem mutex) a