commit 619bb2e0234f900d631b6d2761220c752718cb25 Author: Kegan Myers Date: Fri Aug 21 12:27:26 2015 -0500 initial commit diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..ab124b4 --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +config.json +main diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..db47029 --- /dev/null +++ b/LICENSE @@ -0,0 +1,13 @@ +Copyright (c) 2015, Kegan Myers + +Permission to use, copy, modify, and/or distribute this software for any purpose +with or without fee is hereby granted, provided that the above copyright notice +and this permission notice appear in all copies. + +THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH +REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND +FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, +INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS +OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER +TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF +THIS SOFTWARE. diff --git a/README.md b/README.md new file mode 100644 index 0000000..691a68f --- /dev/null +++ b/README.md @@ -0,0 +1,53 @@ +CFHA +==== +CloudFlare High Availability monitor + +CFHA is a simple daemon that will continually monitor servers you specify and +add/remove them from a shared "A" record in cloudflare. + +Configuration +============= +Configuring CFHA is done through a JSON file, which should be named config.json, +and placed in whatever directory you will run CFHA from. + +Example configuration file: + +```js +{ + "hosts": [ //an array of hosts to check + { + "host": "192.168.1.1", //the IP address of the host + "type": "http", //the type of check to run, can be either http or https + "options": {} //optional additional parameters to the check module + }, + { + "host": "192.168.1.2", + "type": "https", + "options": { + "hostname": "lb-check-hostname" //this is the only currently supported parameter, and will be sent as the "host" header of an http(s) request + } + } + ], + "cloudflare": { //cloudflare configuration + "email": "cfemail@example.com", + "apiKey": "CF_API_KEY", //get this from your cloudflare profile + "domain": "example.com", //the domain in cloudflare you will be operating on + "name": "lb.example.com", //the full dns record you wish to edit + "ttl": "1" //1 is automatic, otherwise see the cloudflare documentation on TTL + }, + "interval": 1 //how often (in seconds) to ping the server, note that this is a number, not a string +} +``` + +Limitations +=========== +CFHA is limited in a few ways, due both to the author, and due to limitations in cloudflare's API / how DNS works. + +1. CFHA can only operate on `A` records since it is invalid to have multiple values for CNAME records. +2. You must specify each host by IP address because CFHA does not resolve names to IP addresses yet. (And we need to have IP addresses for A records). An interesting feature of implementing this is that you could create a pool A record and CFHA would monitor all of those via a single host entry pointing to that record, but it would require a lot more logic. +3. CFHA does not operate on IPv6. This is something that is possible (and maybe even simple) to implement, but has not yet been worked on. +4. CFHA is meant to operate on load balancers, and as such only checks for a 200 exit status on a host. You should add a name-based virtual host to nginx that returns 200 on each monitored server, and set the hostname in the check options. + +License +======= +CFHA is made available under an ISC license. Anyone is welcome to make contributions with the understanding that they will be released under that same license. diff --git a/cloudflare/LICENSE b/cloudflare/LICENSE new file mode 100644 index 0000000..be2cc4d --- /dev/null +++ b/cloudflare/LICENSE @@ -0,0 +1,362 @@ +Mozilla Public License, version 2.0 + +1. Definitions + +1.1. "Contributor" + + means each individual or legal entity that creates, contributes to the + creation of, or owns Covered Software. + +1.2. "Contributor Version" + + means the combination of the Contributions of others (if any) used by a + Contributor and that particular Contributor's Contribution. + +1.3. "Contribution" + + means Covered Software of a particular Contributor. + +1.4. "Covered Software" + + means Source Code Form to which the initial Contributor has attached the + notice in Exhibit A, the Executable Form of such Source Code Form, and + Modifications of such Source Code Form, in each case including portions + thereof. + +1.5. "Incompatible With Secondary Licenses" + means + + a. that the initial Contributor has attached the notice described in + Exhibit B to the Covered Software; or + + b. that the Covered Software was made available under the terms of + version 1.1 or earlier of the License, but not also under the terms of + a Secondary License. + +1.6. "Executable Form" + + means any form of the work other than Source Code Form. + +1.7. "Larger Work" + + means a work that combines Covered Software with other material, in a + separate file or files, that is not Covered Software. + +1.8. "License" + + means this document. + +1.9. "Licensable" + + means having the right to grant, to the maximum extent possible, whether + at the time of the initial grant or subsequently, any and all of the + rights conveyed by this License. + +1.10. "Modifications" + + means any of the following: + + a. any file in Source Code Form that results from an addition to, + deletion from, or modification of the contents of Covered Software; or + + b. any new file in Source Code Form that contains any Covered Software. + +1.11. "Patent Claims" of a Contributor + + means any patent claim(s), including without limitation, method, + process, and apparatus claims, in any patent Licensable by such + Contributor that would be infringed, but for the grant of the License, + by the making, using, selling, offering for sale, having made, import, + or transfer of either its Contributions or its Contributor Version. + +1.12. "Secondary License" + + means either the GNU General Public License, Version 2.0, the GNU Lesser + General Public License, Version 2.1, the GNU Affero General Public + License, Version 3.0, or any later versions of those licenses. + +1.13. "Source Code Form" + + means the form of the work preferred for making modifications. + +1.14. "You" (or "Your") + + means an individual or a legal entity exercising rights under this + License. For legal entities, "You" includes any entity that controls, is + controlled by, or is under common control with You. For purposes of this + definition, "control" means (a) the power, direct or indirect, to cause + the direction or management of such entity, whether by contract or + otherwise, or (b) ownership of more than fifty percent (50%) of the + outstanding shares or beneficial ownership of such entity. + + +2. License Grants and Conditions + +2.1. Grants + + Each Contributor hereby grants You a world-wide, royalty-free, + non-exclusive license: + + a. under intellectual property rights (other than patent or trademark) + Licensable by such Contributor to use, reproduce, make available, + modify, display, perform, distribute, and otherwise exploit its + Contributions, either on an unmodified basis, with Modifications, or + as part of a Larger Work; and + + b. under Patent Claims of such Contributor to make, use, sell, offer for + sale, have made, import, and otherwise transfer either its + Contributions or its Contributor Version. + +2.2. Effective Date + + The licenses granted in Section 2.1 with respect to any Contribution + become effective for each Contribution on the date the Contributor first + distributes such Contribution. + +2.3. Limitations on Grant Scope + + The licenses granted in this Section 2 are the only rights granted under + this License. No additional rights or licenses will be implied from the + distribution or licensing of Covered Software under this License. + Notwithstanding Section 2.1(b) above, no patent license is granted by a + Contributor: + + a. for any code that a Contributor has removed from Covered Software; or + + b. for infringements caused by: (i) Your and any other third party's + modifications of Covered Software, or (ii) the combination of its + Contributions with other software (except as part of its Contributor + Version); or + + c. under Patent Claims infringed by Covered Software in the absence of + its Contributions. + + This License does not grant any rights in the trademarks, service marks, + or logos of any Contributor (except as may be necessary to comply with + the notice requirements in Section 3.4). + +2.4. Subsequent Licenses + + No Contributor makes additional grants as a result of Your choice to + distribute the Covered Software under a subsequent version of this + License (see Section 10.2) or under the terms of a Secondary License (if + permitted under the terms of Section 3.3). + +2.5. Representation + + Each Contributor represents that the Contributor believes its + Contributions are its original creation(s) or it has sufficient rights to + grant the rights to its Contributions conveyed by this License. + +2.6. Fair Use + + This License is not intended to limit any rights You have under + applicable copyright doctrines of fair use, fair dealing, or other + equivalents. + +2.7. Conditions + + Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted in + Section 2.1. + + +3. Responsibilities + +3.1. Distribution of Source Form + + All distribution of Covered Software in Source Code Form, including any + Modifications that You create or to which You contribute, must be under + the terms of this License. You must inform recipients that the Source + Code Form of the Covered Software is governed by the terms of this + License, and how they can obtain a copy of this License. You may not + attempt to alter or restrict the recipients' rights in the Source Code + Form. + +3.2. Distribution of Executable Form + + If You distribute Covered Software in Executable Form then: + + a. such Covered Software must also be made available in Source Code Form, + as described in Section 3.1, and You must inform recipients of the + Executable Form how they can obtain a copy of such Source Code Form by + reasonable means in a timely manner, at a charge no more than the cost + of distribution to the recipient; and + + b. You may distribute such Executable Form under the terms of this + License, or sublicense it under different terms, provided that the + license for the Executable Form does not attempt to limit or alter the + recipients' rights in the Source Code Form under this License. + +3.3. Distribution of a Larger Work + + You may create and distribute a Larger Work under terms of Your choice, + provided that You also comply with the requirements of this License for + the Covered Software. If the Larger Work is a combination of Covered + Software with a work governed by one or more Secondary Licenses, and the + Covered Software is not Incompatible With Secondary Licenses, this + License permits You to additionally distribute such Covered Software + under the terms of such Secondary License(s), so that the recipient of + the Larger Work may, at their option, further distribute the Covered + Software under the terms of either this License or such Secondary + License(s). + +3.4. Notices + + You may not remove or alter the substance of any license notices + (including copyright notices, patent notices, disclaimers of warranty, or + limitations of liability) contained within the Source Code Form of the + Covered Software, except that You may alter any license notices to the + extent required to remedy known factual inaccuracies. + +3.5. Application of Additional Terms + + You may choose to offer, and to charge a fee for, warranty, support, + indemnity or liability obligations to one or more recipients of Covered + Software. However, You may do so only on Your own behalf, and not on + behalf of any Contributor. You must make it absolutely clear that any + such warranty, support, indemnity, or liability obligation is offered by + You alone, and You hereby agree to indemnify every Contributor for any + liability incurred by such Contributor as a result of warranty, support, + indemnity or liability terms You offer. You may include additional + disclaimers of warranty and limitations of liability specific to any + jurisdiction. + +4. Inability to Comply Due to Statute or Regulation + + If it is impossible for You to comply with any of the terms of this License + with respect to some or all of the Covered Software due to statute, + judicial order, or regulation then You must: (a) comply with the terms of + this License to the maximum extent possible; and (b) describe the + limitations and the code they affect. Such description must be placed in a + text file included with all distributions of the Covered Software under + this License. Except to the extent prohibited by statute or regulation, + such description must be sufficiently detailed for a recipient of ordinary + skill to be able to understand it. + +5. Termination + +5.1. The rights granted under this License will terminate automatically if You + fail to comply with any of its terms. However, if You become compliant, + then the rights granted under this License from a particular Contributor + are reinstated (a) provisionally, unless and until such Contributor + explicitly and finally terminates Your grants, and (b) on an ongoing + basis, if such Contributor fails to notify You of the non-compliance by + some reasonable means prior to 60 days after You have come back into + compliance. Moreover, Your grants from a particular Contributor are + reinstated on an ongoing basis if such Contributor notifies You of the + non-compliance by some reasonable means, this is the first time You have + received notice of non-compliance with this License from such + Contributor, and You become compliant prior to 30 days after Your receipt + of the notice. + +5.2. If You initiate litigation against any entity by asserting a patent + infringement claim (excluding declaratory judgment actions, + counter-claims, and cross-claims) alleging that a Contributor Version + directly or indirectly infringes any patent, then the rights granted to + You by any and all Contributors for the Covered Software under Section + 2.1 of this License shall terminate. + +5.3. In the event of termination under Sections 5.1 or 5.2 above, all end user + license agreements (excluding distributors and resellers) which have been + validly granted by You or Your distributors under this License prior to + termination shall survive termination. + +6. Disclaimer of Warranty + + Covered Software is provided under this License on an "as is" basis, + without warranty of any kind, either expressed, implied, or statutory, + including, without limitation, warranties that the Covered Software is free + of defects, merchantable, fit for a particular purpose or non-infringing. + The entire risk as to the quality and performance of the Covered Software + is with You. Should any Covered Software prove defective in any respect, + You (not any Contributor) assume the cost of any necessary servicing, + repair, or correction. This disclaimer of warranty constitutes an essential + part of this License. No use of any Covered Software is authorized under + this License except under this disclaimer. + +7. Limitation of Liability + + Under no circumstances and under no legal theory, whether tort (including + negligence), contract, or otherwise, shall any Contributor, or anyone who + distributes Covered Software as permitted above, be liable to You for any + direct, indirect, special, incidental, or consequential damages of any + character including, without limitation, damages for lost profits, loss of + goodwill, work stoppage, computer failure or malfunction, or any and all + other commercial damages or losses, even if such party shall have been + informed of the possibility of such damages. This limitation of liability + shall not apply to liability for death or personal injury resulting from + such party's negligence to the extent applicable law prohibits such + limitation. Some jurisdictions do not allow the exclusion or limitation of + incidental or consequential damages, so this exclusion and limitation may + not apply to You. + +8. Litigation + + Any litigation relating to this License may be brought only in the courts + of a jurisdiction where the defendant maintains its principal place of + business and such litigation shall be governed by laws of that + jurisdiction, without reference to its conflict-of-law provisions. Nothing + in this Section shall prevent a party's ability to bring cross-claims or + counter-claims. + +9. Miscellaneous + + This License represents the complete agreement concerning the subject + matter hereof. If any provision of this License is held to be + unenforceable, such provision shall be reformed only to the extent + necessary to make it enforceable. Any law or regulation which provides that + the language of a contract shall be construed against the drafter shall not + be used to construe this License against a Contributor. + + +10. Versions of the License + +10.1. New Versions + + Mozilla Foundation is the license steward. Except as provided in Section + 10.3, no one other than the license steward has the right to modify or + publish new versions of this License. Each version will be given a + distinguishing version number. + +10.2. Effect of New Versions + + You may distribute the Covered Software under the terms of the version + of the License under which You originally received the Covered Software, + or under the terms of any subsequent version published by the license + steward. + +10.3. Modified Versions + + If you create software not governed by this License, and you want to + create a new license for such software, you may create and use a + modified version of this License if you rename the license and remove + any references to the name of the license steward (except to note that + such modified license differs from this License). + +10.4. Distributing Source Code Form that is Incompatible With Secondary + Licenses If You choose to distribute Source Code Form that is + Incompatible With Secondary Licenses under the terms of this version of + the License, the notice described in Exhibit B of this License must be + attached. + +Exhibit A - Source Code Form License Notice + + This Source Code Form is subject to the + terms of the Mozilla Public License, v. + 2.0. If a copy of the MPL was not + distributed with this file, You can + obtain one at + http://mozilla.org/MPL/2.0/. + +If it is not possible or desirable to put the notice in a particular file, +then You may include the notice in a location (such as a LICENSE file in a +relevant directory) where a recipient would be likely to look for such a +notice. + +You may add additional accurate notices of copyright ownership. + +Exhibit B - "Incompatible With Secondary Licenses" Notice + + This Source Code Form is "Incompatible + With Secondary Licenses", as defined by + the Mozilla Public License, v. 2.0. diff --git a/cloudflare/README.md b/cloudflare/README.md new file mode 100644 index 0000000..44e1ae7 --- /dev/null +++ b/cloudflare/README.md @@ -0,0 +1,19 @@ +# Note +This is a modification of the original `github.com/pearkes/cloudflare` package, and has changes +that align with the goals of the `cfha` project. Don't + +## cloudflare + +This package provides the `cloudflare` package which offers +an interface to the CloudFlare gAPI. + +It's intentionally designed to make heavy use of built-ins and strings +in place of custom data structures and proper types. It also only implements +specific endpoints, and doesn't have full API coverage. + +**For those reasons, I recommend looking elsewhere if you just need +a standard CloudFlare API client.** + +### Documentation + +The full documentation is available on [Godoc](http://godoc.org/github.com/pearkes/cloudflare) diff --git a/cloudflare/api.go b/cloudflare/api.go new file mode 100644 index 0000000..a5d6723 --- /dev/null +++ b/cloudflare/api.go @@ -0,0 +1,109 @@ +package cloudflare + +import ( + "encoding/json" + "fmt" + "io/ioutil" + "net/http" + "net/url" +) + +// Client provides a client to the CloudflAre API +type Client struct { + // Access Token + Token string + + // User Email + Email string + + // URL to the DO API to use + URL string + + // HttpClient is the client to use. Default will be + // used if not provided. + Http *http.Client +} + +// NewClient returns a new cloudflare client, +// requires an authorization token. You can generate +// an OAuth token by visiting the Apps & API section +// of the CloudflAre control panel for your account. +//-Can't return an error +func NewClient(email string, token string) (*Client) { + //-Removed environment grabbing + client := Client{ + Token: token, + Email: email, + URL: "https://www.cloudflare.com/api_json.html", + Http: http.DefaultClient, + } + return &client +} + +// Creates a new request with the params +func (c *Client) NewRequest(params map[string]string, method string, action string) (*http.Request, error) { + p := url.Values{} + u, err := url.Parse(c.URL) + + if err != nil { + return nil, err + } + + // Build up our request parameters + for k, v := range params { + p.Add(k, v) + } + + // Add authentication details + p.Add("tkn", c.Token) + p.Add("email", c.Email) + + // The "action" to take against the API + p.Add("a", action) + + // Add the params to our URL + u.RawQuery = p.Encode() + + // Build the request + req, err := http.NewRequest(method, u.String(), nil) + + if err != nil { + return nil, err + } + + return req, nil + +} + +// decodeBody is used to JSON decode a body +func decodeBody(resp *http.Response, out interface{}) error { + body, err := ioutil.ReadAll(resp.Body) + + if err != nil { + return err + } + + if err = json.Unmarshal(body, &out); err != nil { + return err + } + + return nil +} + +// checkResp wraps http.Client.Do() and verifies that the +// request was successful. A non-200 request returns an error +// formatted to included any validation problems or otherwise +func checkResp(resp *http.Response, err error) (*http.Response, error) { + // If the err is already there, there was an error higher + // up the chain, so just return that + if err != nil { + return resp, err + } + + switch i := resp.StatusCode; { + case i == 200: + return resp, nil + default: + return nil, fmt.Errorf("API Error: %s", resp.Status) + } +} diff --git a/cloudflare/record.go b/cloudflare/record.go new file mode 100644 index 0000000..4920276 --- /dev/null +++ b/cloudflare/record.go @@ -0,0 +1,189 @@ +package cloudflare + +import ( + "fmt" +) + +//~Return the actual error when possible + +type RecordsResponse struct { + Response struct { + Recs struct { + Records []Record `json:"objs"` + } `json:"recs"` + } `json:"response"` + Result string `json:"result"` + Message string `json:"msg"` +} + +//-Removed wildcard option +func (r *RecordsResponse) FindRecordByName(name string) ([]Record, error) { + if r.Result == "error" { + return nil, fmt.Errorf("API Error: %s", r.Message) + } + + objs := r.Response.Recs.Records + + var recs []Record + + //-Removed errror on no results + //-Removed wildcard checking + //~Checking against FullName, not just name + + for _, v := range objs { + if v.FullName == name { + recs = append(recs, v) + } + } + + return recs, nil +} + +type RecordResponse struct { + Response struct { + Rec struct { + Record Record `json:"obj"` + } `json:"rec"` + } `json:"response"` + Result string `json:"result"` + Message string `json:"msg"` +} + +func (r *RecordResponse) GetRecord() (*Record, error) { + if r.Result == "error" { + return nil, fmt.Errorf("API Error: %s", r.Message) + } + + return &r.Response.Rec.Record, nil +} + +// Record is used to represent a retrieved Record. All properties +// are set as strings. +type Record struct { + Id string `json:"rec_id"` + Domain string `json:"zone_name"` + Name string `json:"display_name"` + FullName string `json:"name"` + Value string `json:"content"` + Type string `json:"type"` + Priority string `json:"prio"` + Ttl string `json:"ttl"` +} + +// CreateRecord contains the request parameters to create a new +// record. +type CreateRecord struct { + Type string + Name string + Content string + Ttl string + Priority string +} + +// CreateRecord creates a record from the parameters specified and +// returns an error if it fails. If no error and the name is returned, +// the Record was succesfully created. +func (c *Client) CreateRecord(domain string, opts *CreateRecord) (*Record, error) { + // Make the request parameters + params := make(map[string]string) + //-No option checking, we set them all ourselves + params["z"] = domain + params["type"] = opts.Type + params["name"] = opts.Name + params["content"] = opts.Content + params["prio"] = opts.Priority + params["ttl"] = "1" + + req, err := c.NewRequest(params, "POST", "rec_new") + if err != nil { + return nil, err + } + + resp, err := checkResp(c.Http.Do(req)) + + if err != nil { + return nil, err + } + + recordResp := new(RecordResponse) + + err = decodeBody(resp, &recordResp) + + if err != nil { + return nil, err + } + record, err := recordResp.GetRecord() + if err != nil { + return nil, err + } + + // The request was successful + return record, nil +} + +// DestroyRecord destroys a record by the ID specified and +// returns an error if it fails. If no error is returned, +// the Record was succesfully destroyed. +func (c *Client) DestroyRecord(domain string, id string) error { + params := make(map[string]string) + params["z"] = domain + params["id"] = id + + req, err := c.NewRequest(params, "POST", "rec_delete") + if err != nil { + return err + } + + resp, err := checkResp(c.Http.Do(req)) + + if err != nil { + return err + } + + recordResp := new(RecordResponse) + + err = decodeBody(resp, &recordResp) + + if err != nil { + return err + } + _, err = recordResp.GetRecord() + if err != nil { + return err + } + + // The request was successful + return nil +} + +func (c *Client) RetrieveRecordsByName(domain string, name string) ([]Record, error) { + params := make(map[string]string) + params["z"] = domain + + req, err := c.NewRequest(params, "GET", "rec_load_all") + + if err != nil { + return nil, err + } + + resp, err := checkResp(c.Http.Do(req)) + if err != nil { + return nil, err + } + + records := new(RecordsResponse) + + err = decodeBody(resp, records) + + if err != nil { + return nil, err + } + + record, err := records.FindRecordByName(name) + if err != nil { + return nil, err + } + + // The request was successful + return record, nil +} diff --git a/main.go b/main.go new file mode 100644 index 0000000..ed76fc9 --- /dev/null +++ b/main.go @@ -0,0 +1,31 @@ +package main + +import ( + "log" + "fmt" + "io/ioutil" + "encoding/json" + "./monitor" +) + +func main() { + file, err := ioutil.ReadFile("./config.json") + if err != nil { + log.Fatal(fmt.Sprintf("%v\n", err)) + } + + c := monitor.Config{} + json.Unmarshal(file, &c) + + handlers := make([]monitor.GenericHandler, 2) + handlers[0] = monitor.NewLogHandler() + handlers[1] = monitor.NewCloudflareHandler(c.Cloudflare) + + engine := monitor.CreateEngine(handlers) + + for _, endpoint := range c.Hosts { + monitor.CreateCheck(c.Interval, engine, endpoint) + } + + select{} +} diff --git a/monitor/cloudflare.go b/monitor/cloudflare.go new file mode 100644 index 0000000..5ff1f26 --- /dev/null +++ b/monitor/cloudflare.go @@ -0,0 +1,75 @@ +package monitor + +import ( + "../cloudflare" + "log" + "fmt" +) + +func NewCloudflareHandler(config CloudflareConfig) GenericHandler { + return runHandler(make(chan Transition, 5), &cloudflareHandler{ + config, + cloudflare.NewClient(config.Email, config.ApiKey), + make(map[string]bool), + }) +} + +type cloudflareHandler struct{ + config CloudflareConfig + client *cloudflare.Client + actuallyDownHosts map[string]bool +} + +func (this *cloudflareHandler) handle(transition Transition) { + switch transition.To { + case Down: + log.Print(fmt.Sprintf( + "Removed cloudflare record for `%s`: `%v`\n", + transition.RecordValue, + removeCloudflareRecord(this.client, this.config, transition.RecordValue))) + + case Up: + log.Print(fmt.Sprintf( + "Added cloudflare record for `%s`: `%v`\n", + transition.RecordValue, + addCloudflareRecord(this.client, this.config, transition.RecordValue))) + + case Unknown: //just leave it how it was, going up/down is idempotent anyways + } +} + +func removeCloudflareRecord(client *cloudflare.Client, config CloudflareConfig, recordValue string) bool { + records, err := client.RetrieveRecordsByName(config.Domain, config.Name) + + if err != nil { + return false + } + + exitStatus := true + for _, record := range records { + if record.Value != recordValue { + continue + } + + exitStatus = exitStatus && client.DestroyRecord(config.Domain, record.Id) == nil + } + + return exitStatus +} + +func addCloudflareRecord(client *cloudflare.Client, config CloudflareConfig, recordValue string) bool { + opts := cloudflare.CreateRecord{ + "A", + config.Name, + recordValue, + "1", + "0", + } + + _, err := client.CreateRecord(config.Domain, &opts) + + if err != nil { + return fmt.Sprintf("%s", err) == "API Error: The record already exists." + } + return true +} diff --git a/monitor/config.go b/monitor/config.go new file mode 100644 index 0000000..523f492 --- /dev/null +++ b/monitor/config.go @@ -0,0 +1,21 @@ +package monitor + +type HostConfig struct { + Host string + Type string + Options map[string]string +} + +type CloudflareConfig struct { + Email string + ApiKey string + Domain string + Name string + Ttl string +} + +type Config struct { + Cloudflare CloudflareConfig + Hosts []HostConfig + Interval uint16 +} diff --git a/monitor/createCheck.go b/monitor/createCheck.go new file mode 100644 index 0000000..cf6459b --- /dev/null +++ b/monitor/createCheck.go @@ -0,0 +1,70 @@ +package monitor + +import ( + "net/http" + "time" + "log" + "fmt" +) + +type checkConfig struct { + engine *Engine + interval time.Duration + host HostConfig +} + +type httpChecker struct { + client *http.Client + config checkConfig + endpoint string +} + +func (this *httpChecker) run() { + log.Print(fmt.Sprintf("Starting: %v\n", this.config.host)) + for true { + this.config.engine.Input<- Result{ + this.config.host.Host, + this.check(), + } + time.Sleep(this.config.interval) + } +} + +func (this *httpChecker) check() Status { + req, err := http.NewRequest("GET", this.endpoint, nil) + if err != nil { + log.Print(fmt.Sprintf("Stopping: %v due to http NewRequest error\n", this.config.host)) + return Unknown + } + req.Header.Set("Host", this.config.host.Options["hostname"]) + return this.determineHttpCheckStatus(this.client.Do(req)) +} + +func (this *httpChecker) determineHttpCheckStatus(res *http.Response, err error) Status { + if err != nil || res.StatusCode != 200 { + return Down + } + return Up +} + +func newHttpChecker(config checkConfig) *httpChecker { + checker := httpChecker{ + &http.Client{}, + config, + config.host.Type + "://" + config.host.Host + "/", + } + go checker.run() + return &checker +} + +func CreateCheck(interval uint16, engine *Engine, host HostConfig) { + config := checkConfig{ + engine, + time.Duration(int64(interval)) * time.Second, + host, + } + switch host.Type { + case "http", "https": + newHttpChecker(config) + } +} diff --git a/monitor/engine.go b/monitor/engine.go new file mode 100644 index 0000000..98e29ad --- /dev/null +++ b/monitor/engine.go @@ -0,0 +1,51 @@ +package monitor + +import ( +) + +type Engine struct { + Input chan Result + output []GenericHandler +} + +func CreateEngine(handlers []GenericHandler) *Engine { + input := make(chan Result) + + engine := Engine{ + input, + handlers, + } + + e := &engine + + go e.startProcessor() + + return e +} + +func (this *Engine) startProcessor() { + statuses := make(map[string]Status) + for true { + result := <-this.Input + + //No transition if we don't exist + if result.Status == statuses[result.RecordValue] { + continue + } + + //Create a record with to, from + change := Transition{ + result.Status, + statuses[result.RecordValue], + result.RecordValue, + } + + //Send the record to everyone who cares + for _, relay := range this.output { + relay.channel<- change + } + + //And set our new status + statuses[result.RecordValue] = result.Status + } +} diff --git a/monitor/handler.go b/monitor/handler.go new file mode 100644 index 0000000..99b27c4 --- /dev/null +++ b/monitor/handler.go @@ -0,0 +1,20 @@ +package monitor + +type handler interface{ + handle(transition Transition) +} + +type GenericHandler struct { + channel chan Transition +} + +func runHandler(input chan Transition, handler handler) GenericHandler { + go func() { + for true { + handler.handle(<-input) + } + }() + return GenericHandler{ + input, + } +} diff --git a/monitor/log.go b/monitor/log.go new file mode 100644 index 0000000..9be1b92 --- /dev/null +++ b/monitor/log.go @@ -0,0 +1,19 @@ +package monitor + +import ( + "fmt" + "log" +) + +func NewLogHandler() GenericHandler { + return runHandler(make(chan Transition), &logHandler{}) +} + +type logHandler struct{} + +func (this *logHandler) handle(transition Transition) { + log.Print(fmt.Sprintf( + "`%s` has become `%d` - `%s`", + transition.RecordValue, transition.To, + transition.To.String())) +} diff --git a/monitor/result.go b/monitor/result.go new file mode 100644 index 0000000..530bcfd --- /dev/null +++ b/monitor/result.go @@ -0,0 +1,6 @@ +package monitor + +type Result struct { + RecordValue string + Status Status +} diff --git a/monitor/transition.go b/monitor/transition.go new file mode 100644 index 0000000..4afcb1a --- /dev/null +++ b/monitor/transition.go @@ -0,0 +1,27 @@ +package monitor + +type Status int + +const ( + Unknown Status = iota + Up Status = iota + Down Status = iota +) + +func (t Status) String() string { + if t == Unknown { + return "Unknown" + } else if t == Up { + return "Up" + } else if t == Down { + return "Down" + } + return "" +} + +type Transition struct { + To Status + From Status + RecordValue string +} +