Update API seems to be silently failing on certain requests

[jmiranda]

Email from Luis:

I tried to make an edit to a test annotation and though the request gave me an OK, the changes were not saved/made. I've included the HAR file from the PUT request.

[jmiranda]

Steps to reproduce:

• Log into class on Edge (https://edge.edx.org/courses/course-v1:HarvardX+GA001+2015/courseware/5973831144094181854e31a054175cbd/478f6cd8f1d74b1a81ae77f05451961a/7?activate_block_id=block-v1%3AHarvardX%2BGA001%2B2015%2Btype%40vertical%2Bblock%40b4c106df8b75458289f87731a9f547c1)
• This course here should have the lti. It should be in the "Grape Ape" course under "Edx Tools" / "LTI" / "LTI Inspector"
• On the top you should make sure you are in "View this course as: Student" then clicked the last link on the page labeled "Annotation LTI Tool Testing"

[jmiranda]

Update annotation via cURL:

$  curl -i -X POST -H "Content-Type: application/json" -H "x-annotator-auth-token: (AUTHTOKEN REDACTED)" -d "{\"tags\":[\"\"],\"citation\":\"None\",\"text\":\"Nine edited\",\"totalComments\":0,\"collectionId\":\"9c2e3171-9e8c-41f3-b49a-70284f1b28b9\",\"ranges\":[{\"endOffset\":27,\"start\":\"/span[9]\",\"end\":\"/span[9]\",\"startOffset\":0}],\"deleted\":false,\"uri\":2,\"id\":121023,\"contextId\":\"a6bdb8d488f1b096a4b19e68e31afb88c2268b3c\",\"archived\":false,\"created\":\"2015-08-10T14:59:22 UTC\",\"updated\":\"2015-08-10T14:59:22 UTC\",\"quote\":\"Now he'll never come again.\",\"permissions\":{\"update\":[\"2c2faf9d71aa37e974c72c098cf9466b45d319ae\"],\"admin\":[\"2c2faf9d71aa37e974c72c098cf9466b45d319ae\"],\"delete\":[\"2c2faf9d71aa37e974c72c098cf9466b45d319ae\"],\"read\":[]},\"media\":\"text\",\"user\":{\"id\":\"2c2faf9d71aa37e974c72c098cf9466b45d319ae\",\"name\":\"Luis Duarte\"}}" https://catch-dev.harvardx.harvard.edu/catch/annotator/update/121023

HTTP/1.1 200 OK
Date: Mon, 17 Aug 2015 17:06:02 GMT
Server: Apache-Coyote/1.1
Content-Type: application/json;charset=UTF-8
Content-Length: 702

{"tags":[""],"citation":"None","text":"Nine edited","totalComments":0,"collectionId":"9c2e3171-9e8c-41f3-b49a-70284f1b28b9","ranges":[{"endOffset":27,"start":"/span[9]","end":"/span[9]","startOffset":0}],"deleted":false,"uri":2,"id":121023,"contextId":"a6bdb8d488f1b096a4b19e68e31afb88c2268b3c","archived":false,"created":"2015-08-10T14:59:22 UTC","updated":"2015-08-10T14:59:22 UTC","quote":"Now he'll never come again.","permissions":{"update":["2c2faf9d71aa37e974c72c098cf9466b45d319ae"],"admin":["2c2faf9d71aa37e974c72c098cf9466b45d319ae"],"delete":["2c2faf9d71aa37e974c72c098cf9466b45d319ae"],"read":[]},"media":"text","user":{"id":"2c2faf9d71aa37e974c72c098cf9466b45d319ae","name":"Luis Duarte"}}

Read latest version of annotation

$ curl -i -X GET -H "Content-Type: application/json" -H "x-annotator-auth-token: (AUTHTOKEN REDACTED)" https://catch-dev.harvardx.harvard.edu/catch/annotator/read/121023

HTTP/1.1 200 OK
Date: Mon, 17 Aug 2015 17:06:49 GMT
Server: Apache-Coyote/1.1
Content-Type: application/json;charset=UTF-8
Content-Length: 695

{"tags":[""],"citation":"None","text":"Nine","totalComments":0,"collectionId":"9c2e3171-9e8c-41f3-b49a-70284f1b28b9","ranges":[{"endOffset":27,"start":"/span[9]","end":"/span[9]","startOffset":0}],"deleted":false,"uri":2,"id":121023,"contextId":"a6bdb8d488f1b096a4b19e68e31afb88c2268b3c","archived":false,"created":"2015-08-10T14:59:22 UTC","updated":"2015-08-10T14:59:22 UTC","quote":"Now he'll never come again.","permissions":{"update":["2c2faf9d71aa37e974c72c098cf9466b45d319ae"],"admin":["2c2faf9d71aa37e974c72c098cf9466b45d319ae"],"delete":["2c2faf9d71aa37e974c72c098cf9466b45d319ae"],"read":[]},"media":"text","user":{"id":"2c2faf9d71aa37e974c72c098cf9466b45d319ae","name":"Luis Duarte"}}

[jmiranda]

Turns out the API fails silently when the tags attribute contains an array with an empty string. Luis has fixed this within the client (by settings the tags attribute to an empty array or null), but the API should not fail silently in the case that tags is an array with an empty string. I think the proper behavior should be an exception, but I'm open to ignoring the empty string as well.