HTTP API

    The HTTP API is RESTful in nature but provides alternative access through various overrides since not all clients can adhere to a strict REST protocol. The default data exchange is via JSON though pluggable may be accessed, via the request, to send or receive data in different formats. Standard HTTP response codes are used for all returned results and errors will be returned as content using the proper format.

    Version 1.X to 2.x

    OpenTSDB 1.x had a simple HTTP API that provided access to common behaviors such as querying for data, auto-complete queries and static file requests. OpenTSDB 2.0 introduces a new, formalized API as documented here. The 1.0 API is still accessible though most calls are deprecated and may be removed in version 3. All 2.0 API calls start with /api/.

    Serializers

    2.0 introduces pluggable serializers that allow for parsing user input and returning results in different formats such as XML or JSON. Serializers only apply to the 2.0 API calls, all 1.0 behave as before. For details on Serializers and options supported, please read HTTP Serializers

    All API calls use the default JSON serializer unless overridden by query string or Content-Type header. To override:

    • Query String - Supply a parameter such as serializer=<serializer_name> where <serializer_name> is the hard-coded name of the serializer as shown in the /api/serializers serializer output field.

      Warning

      If a serializer isn’t found that matches the <serializer_name> value, the query will return an error instead of processing further.

    • Content-Type - If a query string is not given, the TSD will parse the Content-Type header from the HTTP request. Each serializer may supply a content type and if matched to the incoming request, the proper serializer will be used. If a serializer isn’t located that maps to the content type, the default serializer will be used.

    The API documentation will display requests and responses using the JSON serializer. See plugin documentation for the ways in which serializers alter behavior.

    Note

    The JSON specification states that fields can appear in any order, so do not assume the ordering in given examples will be preserved. Arrays may be sorted and if so, this will be documented.

    Authentication/Permissions

    As of yet, OpenTSDB lacks an authentication and access control system. Therefore no authentication is required when accessing the API. If you wish to limit access to OpenTSDB, use network ACLs or firewalls to block access. We do not recommend running OpenTSDB on a machine with a public IP Address.

    Every request will be returned with a standard HTTP response code. Most responses will include content, particularly error codes that will include details in the body about what went wrong. Successful codes returned from the API include:

    Common error response codes include:

    Errors

    If an error occurs, the API will return a response with an error object formatted per the requested response type. Error object fields include:

    All errors will return with a valid HTTP status error code and a content body with error details. The default formatter returns error messages as JSON with the application/json content-type. If a different formatter was requested, the output may be different. See the formatter documentation for details.

    Note that the stack trace is truncated. Also, the trace will include system specific line endings (in this case \r\n for Windows). If displaying for a user or writing to a log, be sure to replace the \n or \r\n and \r characters with new lines and tabs.

    Verbs

    The HTTP API is RESTful in nature, meaning it does its best to adhere to the REST protocol by using HTTP verbs to determine a course of action. For example, a GET request should only return data, a PUT or POST should modify data and DELETE should remove it. Documentation will reflect what verbs can be used on an endpoint and what they do.

    However in some situations, verbs such as DELETE and PUT are blocked by firewalls, proxies or not implemented in clients. Furthermore, most developers are used to using GET and POST exclusively. Therefore, while the OpenTSDB API supports extended verbs, most requests can be performed with just GET by adding the query string parameter method_override. This parameter allows clients to pass data for most API calls as query string values instead of body content. For example, you can delete an annotation by issuing a with a query string /api/annotation?start_time=1369141261&tsuid=010101&method_override=delete. The following table describes verb behavior and overrides.

    If a method is not supported for a given API call, the TSD will return a 405 error.

    Note

    The HTTP specification states that there shouldn’t be an association between data passed in a request body and the URI in a GET request. Thus OpenTSDB’s API does not parse body content in GET requests. You can, however, provide a query string with data and an override for updating data in certain endpoints. But we recommend that you use POST for anything that writes data.

    API Versioning

    OpenTSDB 2.0’s API call calls are versioned so that users can upgrade with gauranteed backwards compatability. To access a specific API version, you craft a URL such as /api/v<version>/<endpoint> such as /api/v2/suggest. This will access version 2 of the suggest endpoint. Versioning starts at 1 for OpenTSDB 2.0.0. Requests for a version that does not exist will result in calls to the latest version. Also, if you do not supply an explicit version, such as /api/suggest, the latest version will be used.

    Most of the API endpoints support query string parameters, particularly those that fetch data from the system. However due to the complexities of encoding some characters, and particularly Unicode, all endpoints also support access via POST content using formatters. The default format is JSON so clients can use their favorite means of generating a JSON object and send it to the OpenTSDB API via a POST request. POST requests will generally provided greater flexibility in the fields offered and fully Unicode support than query strings.

    Compressed Requests

    The API can accept body content that has been compressed. Make sure to set the Content-Encoding header to gzip and pass the binary encoded data over the wire. This is particularly useful for posting data points to the /api/put endpoint. An example using curl:

    1. $ gzip -9c clear-32k.json > gzip-32k.json
    3. $ file gzip-32k.json
    4. gzip-32k.json: gzip compressed data, was "clear-32k.json", from Unix, last modified: Thu Jan 16 15:31:55 2014
    6. $ ls -l gzip-32k.json
    7. -rw-r--r-- 1 root root 1666 févr.  4 09:57 gzip-32k.json
    9. $ curl -X POST --data-binary "@gzip-32k.json" --header "Content-Type: application/json" --header "Content-Encoding: gzip" http://mytsdb1:4242/api/put?details
    10. {"errors":[],"failed":0,"success":280}

    CORS

    OpenTSDB provides simple and preflight support for Cross-Origin Resource Sharing (CORS) requests. To enable CORS, you must supply either a wild card * or a comma separated list of specific domains in the tsd.http.request.cors_domains configuration setting and restart OpenTSDB. For example, you can supply a value of or you could provide a list of domains such as beeblebrox.com,www.beeblebrox.com,aurtherdent.com. The domain list is case insensitive but must fully match any value sent by clients.

    When a GET, POST, PUT or DELETE request arrives with the Origin header set to a valid domain name, the server will compare the domain against the configured list. If the domain appears in the list or the wild card was set, the server will add the Access-Control-Allow-Origin and Access-Control-Allow-Methods headers to the response after processing is complete. The allowed methods will always be GET, POST, PUT, DELETE. It does not change per end point. If the request is a CORS preflight, i.e. the OPTION method is used, the response will be the same but with an empty content body and a 200 status code.

    If the Origin domain did not match a domain in the configured list, the response will be a 200 status code and an Error (see above) for the content body stating that access was denied, regardless of whether the request was a preflight or a regular request. The request will not be processed any further.

    By default, the tsd.http.request.cors_domains list is empty and CORS is diabled. Requests are passed through without appending CORS specific headers. If an Options request arrives, it will receive a 405 error message.

    Note

    Do not rely on CORS for security. It is exceedingly easy to spoof a domain in an HTTP request and OpenTSDB does not perform reverse lookups or domain validation. CORS is only implemented as a means to make it easier JavaScript developers to work with the API.

    Documentation

    The documentation for each endpoint listed below will contain details about how to use that endpoint. Eahc page will contain a description of the endpoint, what verbs are supported, the fields in a request, fields in a respone and examples.

    Request Parameters are a list of field names that you can pass in with your request. Each table has the following information:

    • Name - The name of the field

    • Data Type - The type of data you need to supply. E.g. String should be text, Integer must be a whole number (positive or negative), Float should be a decimal number. The data type may also be a complex object such as an array or map of values or objects. If you see Present in this column then simply adding the parameter to the query string sets the value to true, the actual value of the parameter is ignored. For example /api/put?summary will effectively set summary=true. If you request /api/put?summary=false, the API will still consider the request as summary=true.

    • Required - Whether or not the parameter is required for a successful query. If the parameter is required, you’ll see Required otherwise it will be Optional.

    • Description - A detailed description of the parameter including what values are allowed if applicable.

    • Default - The default value of the Optional parameter. If the data is required, this field will be blank.

    • QS - If the parameter can be supplied via query string, this field will have a in it, otherwise it will have a No meaning the parameter can only be supplied as part of the request body content.

    • RW - Describes whether or not this parameter can result in an update to data stored in OpenTSDB. Possible values in this column are:

      • RO - A field that appears in the response but is read only. The value passed along with a request will not alter the output field.

      • RW or W - A field that will result in an update to the data stored in the system

    • Example - An example of the parameter value

    API Endpoints