diff --git a/models/event.js b/models/event.js
index 1ca73b7f..db86245e 100644
--- a/models/event.js
+++ b/models/event.js
@@ -19,6 +19,7 @@ const MODEL = {
     createTime: Joi
         .string()
         .isoDate()
+        .max(32)
         .description('When this event was created')
         .example('2038-01-19T03:14:08.131Z'),
     creator: Scm.user
@@ -28,7 +29,7 @@ const MODEL = {
         .description('Identifier of this pipeline')
         .example(123345),
     sha: Joi
-        .string().hex()
+        .string().hex().length(40)
         .description('SHA this project was built on')
         .example('ccc49349d3cffbd12ea9e3d41521480b4aa5de5f'),
     type: Joi
diff --git a/models/pipeline.js b/models/pipeline.js
index 404c3ee0..88b412c1 100644
--- a/models/pipeline.js
+++ b/models/pipeline.js
@@ -22,7 +22,7 @@ const MODEL = {
         .example(123345),
 
     scmUri: Joi
-        .string().regex(Regex.SCM_URI)
+        .string().regex(Regex.SCM_URI).max(128)
         .description('Unique identifier for the application')
         .example('github.com:123456:master'),
 
diff --git a/models/user.js b/models/user.js
index 072863ea..6460fec1 100644
--- a/models/user.js
+++ b/models/user.js
@@ -11,6 +11,7 @@ const MODEL = {
 
     username: Joi
         .string()
+        .max(128)
         .description('Username')
         .example('batman123'),